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CLAY FINISHES STRAW LI M E WOOD
INDEX
U5 – FINISHES
U5 TIME
PAGE 5
U5 Learning Outcomes U5 S1 : Straw-Direct-Plaster (Theory) ca. 4 hrs. Info: Clay & Lime on Straw, Ex. Straw Bale Houses, Building Physics Info: Plaster Ground-Overview Tips: Direct Plaster on Straw - what to keep in mind
7 8 11 12
001 -1 2 Clay and Lime on Straw, 002-1 3 air - and windproof surfaces, 003-1 4 Plaster rules from hard to soft - reinforcement, 004-1 5 Plasters as bracing layers, 005-1 6 Diagonal Bracing with Clay, 005-1 7 Boards as bracing layers
U5 S2: Preparation of the Wall Tips: Preparation of the Wall
2 days
19 20
006-21 Shaving/Cutting, 007-22 plugging Holes, 008-23 Montage of Plaster Grounds 009-24 Sealing Joints, 010-25Taping, 011 -26 insulating Window Frames, 01 2-27 Drip Noses, 01 3-28 Heating- and electric Installations, 01 4-29Tiles/Tadelakt
U5 S3: Preparation of the Clay Plaster Tips: Preparation of the Clay/Earth Plaster 01 5-34 Manual mixing, 01 6-35 compulsory mixer
1 day
31 33
U5 S4: Clay/Earth Base Coat Tips: Clay/Earth Base Coat
1 day
37 38
U5 S5: Clay/Earth Top Coat Tips: Surfaces - Finishes
1 day
43 44
U5 S6: Preparation of the Lime Plaster Info: Lime and Lime Circle
1 day
49 50
U5 S7: Lime Base Coat(s) Info: Lime Base Coat
1 day
53 54
U5 S8: Lime Top Coat Info: LimeTop Coat
1 day
57 58
U5 S9: Cladding (Theory) ca. 2 Std. Tips: Claddings on Straw Bale Houses (Examples) Inspiration: Claddings (Examples)
59 60 62
1 day
65
01 8-39 Clay-Mix, 019-40 Spray-Plaster, 020-41 Tools
021 -45Textured-/Smoothed Plaster, 022-46 Clay Colours, 023-47 Sgraffito & Co
U5 S10: Cladding (Practice)
Credits and Impress
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LEARNING OUTCOMES
U5 Level 3 (ECVET credit points: 1 5) / Level 4 (15)
Knowledge Trainees know … • about the existing relevant national regulations related to straw bale building • the tools and machines used on the building site for plastering and cladding straw bale walls. • the possible dangers, safe working practices, accident prevention regulations and security data sheets (lime). • about the specifics of plaster/render materials, and their properties. • the techniques to make proper mixtures and how to work with • about the specifics of the cladding materials and fastenings, their advantages and disadvantages. • the appropriate connections for cladding and their dimensions (windows, doors, corners, base and roof). • the basics of weather proofing, wind- and airtightness, fire protection and vapour barriers for rendering/plastering finishes of straw bale building • why and how to make rendering/plaster samples to choose the right mixture • the different surface structures and treatments and their properties. • how to prepare the substrate for the plaster or the cladding system.
Skills Trainees can … • handle tools and machines which are used for different plastering/rendering and cladding systems. • prepare the substrate for the coverings. • prepare the plaster/render mixture. • execute different plaster systems. • install the supporting constructions for cladding. • prepare and install the cladding systems. • estimate the dangers of handling with these materials and can minimise risks (lime). • execute proper airtightness, wind- and rainproof details and take care for good rainwater drainage. • calculate the rendering/plastering and cladding quantities. • apply different surface structures, treatments and protecting paint coats.
Competence
Trainees can … • organize and attend the coverings* on building site at all stages and adapt the working process, the use oftools and adequate techniques related to straw bale wrapping (planning, preparation, execution, additional crafts). • coordinate and communicate the special needs of wrapping constructions with other professionals. • can explain different methods ofcoverings with reference to advantages and disadvantages.
*refers to both plasters and claddings
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SESSION PLAN S1
U5 – FINISHES
U5
Direct Plaster Theory Objectives: Trainees ... … explain the basic functions of outside finishes (renders) and inside finishes (plasters). … explain various methods of rendering, work out advantages and disadvantages of each and can address important concerns of the methods. … explain several types of rendering.
Methods:
Theory
Lecture/talk Explanations
The different functions of renderings and plasters: Fire protection Weather proofing Airtightness (inside) and windtightness (outside) Humidity regulation Permeable qualities in relation to humidity (liquid, gas) Thermal mass performance Structural performance Rodent and insect protection Design and decoration Acoustic performance Electromagnetic wave radiation performance The appropriate design for choosing outside rendering according to local climate Function and physics of different layers of plaster The function as load bearing material How they are applied on each other (from hard to soft) The basics about earth/clay as binding material The basics about lime as binding material (air, hydraulic) The basics about coating with paint and its function for humidity regulation Organize building site, check scaffolding condition, materials and tools according to the topic Calculate the quantities of materials needed
Trainer:
Place:
Classroom
Duration: 1 day
Equipment:
Beamer (projector) Flip chart and pens Info sheets Videos Samples
Documents:
Info sheets: I1 Examples of lime and clay finishes I2 Different functions of renders and plasters I3 Methods of applying plaster/render I4 Examples of good and bad building practices – Tamera game Text sheets: X1 Exercise sheets: E1
Evaluation:
Game with questionnaire Multiple choice
Organization:
Prepare copies of info sheets.
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Direct Plaster Theory: The Function of Plasters
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SESSION PLAN S1
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SESSION PLAN S1
U5
Plastered Straw Bale House Examples
CLAY/EARTH
LIME
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Surfaces & Building Physics
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SESSION PLAN S1 - INFO
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Plaster Grounds
SESSION PLAN S1 - INFO
U5
Straw Bales Density min. 100 kg, 36 cm thick Surface shaved and stuffed Price: around € 10,- to 1 7,40/m2 (cert.) Reed Stucco Rolls, 1 Halm each cm metal wire bound, fix with Brackets Price: € 2,00 to 2,60/m2 Glasfibre-Mesh Rolls, Mesh size 10-1 3 mm fix with Brackets Preis: € 2,20/m2 Flax-Mesh , Jute-Mesh Rolls, Mesh size 5 mm fix with Brackets Price Flax: € 3,50/m2, Jute: € 20,-/m2 Reedmatt (bound with metal wire) Boards, 2 and 5 cm thick Fixation: Plate-Srews/Impact dowels Price 2 cm: € 1 2,40/m2, 5 cm:1 4,60/m2 Heraklith Woodchipb. Magnesit bound Boards, 8 and 35 mm thick Fixation: Plate-Srews/IBrackets M8: 10,08/m2, BM35: € 22,30/m2, Softwood Board (Steico) Boards, 8 mm to 8 cm thick Fixation: Plate-Srews/IBrackets Price 8 mm: € 3,26/m2, 4 cm:1 3,86/m2 Steico underfloor (Sound Ins. Board) Boards, 3/4/5/7 mm thick fix with brackets Price: 3 mm: € 1 ,1 4/m2 Clay Board Boards, 1 6 and 22 mm thick Fixation: Plate-Srews/IBrackets 1 6 mm: € 23,25/m2, 22 mm: 25,08/m2 Fermacell Gypsum Board also damp-proof B. , 10/1 2,5/1 5/1 8 mm Fixation: Plate-Srews/IBrackets 10 mm: € 8,50, 1 5 mm: € 1 5,25/m2
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SESSION PLAN S1 - TIPS
Direct Plaster Theory: The Function of Plasters
001 Clay and Lime on Straw: What to keep in mind?
Straw surfaces - properly prepared - are excellent plaster grounds. For this, straw bales must be compressed well (minimum density 100 kg / m3), the surfaces must be smoothed with a hedge trimmer and hollow spaces should be filled with straw that is as long as possible. It is not advisable to store the straw bales a long time so that the smooth but protective wax layer disappears. The surface is rough enough when cut/shaved so that the clay and lime plasters have a durable connection to the straw bales (the halms are cut off with the hedge trimmer with strong pressure). Excessed wood parts wider than 2 cm must be covered with an additional plaster carrier (reed stucco, woodfiber board, Heraklith BM, cork, Steico underfloor) or heavily roughened (every 3 cm incised) to be air- and wind-tight, connections to Window frames, doors, roundwood stands, etc. have to be sealed (tape, Apu strips, multiple plastering). Metals in contact with the plaster area must be permanently rust-free (Stainless steel, zinc, aluminum). Clay as a hygroscopic material transports and shows rust and other "colors" from deeper layers (e.g. an old chimney) to the surface (if this is not painted or limewashed).
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SESSION PLAN S1 - TIPS
Direct Plaster Theory: The Function of Plasters
U5
002 Importance of air- and windproof Surfaces (Plasters)
If no air- and wind-tight panels (OSB, Egger DHF, Agepan DWD and UDP, damp proof boards, Fermacell, wood fiber boards protect) or PE membranes (diagonal bracing with air or windproof membranes underneath) are used to plank straw bale walls (which usually have to be covored again with a plaster carrier, but they provide double safety), the plaster surfaces alone are responsible for the air and wind tightness of the surfaces. Of course, cracks in the first plaster layer are closed at the latest with the second (or third) top plaster layer so that plasters usually provide good air- and windproofness on continuous surfaces, but pipes, wooden beams and, in particular connections to window- and doorframes are not air-tight (and windproof), because of a shrinking of the material when it dries. The wind blows even through the smallest gaps on the facade, not only reducing the insulation value of the straw bales (convection) but causing water in winter in the dewpoint-area (this problem should not be underestimated). And it ultimately cools down the interior air - especially in the case of leaky sockets. The heating need increases exponentially since both cool or cold surface temperatures of the outer walls as well as convection in the interior can reduce the living comfort so much, that room temperatures around 20 ° C are no longer sufficient to feel comfortable.
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SESSION PLAN S1 - TIPS
Direct Plaster Theory: Composition of Plasters
003 Plaster Rule from hard to soft: Reinforcement inst. of hard ground In case of solid, stable plaster grounds, the old plaster rule "from hard to soft" must be taken into consideration. By this it is meant that a gradient of strength should be provided from the plaster ground to the plaster surface. Which means: The top plaster layers should always be softer than their base (or just as tight). If this rule is not observed, there may be stresses between the plaster layers, which may endanger the adhesion of the surface plaster or lead to a disconnection of the plaster from the base (the wall). If, however, the plaster base is softer and more flexible than the plaster layer, as is the case with insulating masonry, light clay, straw bales or thermal insulation materials, the old plaster rule can no longer be used. In this case, the plaster is exposed both to the movements of the insulating plaster ground, as well as to the stresses of temperature and humidity fluctuations. It can not release the resulting stresses to the substrate since this is too soft. Thus it must be able to absorb the stresses in itself. The plaster "floats" then somehow on the "soft" ground. The upper plaster is decoupled from the substrate by a movable and deformable intermediate layer [KĂźnzel, 2003, p. 58]. This task is now provided by the reinforcement of the plaster. It is "armored" to take up movements. This is done either by a fibercontaining plaster mortar or by the full-surface insertion of a fabric (flax, glass fiber, jute mesh).
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Source/Tip: Irmela Romme, Uta Herz: Lehm- und Kalkputze (Ă–kobuch-Verlag, 2012)
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SESSION PLAN S1 - TIPS
U5
TEST CUT-WAND
Direct Plaster Theory: The Function of Plasters
004 Plasters as bracing Layers
It is logical in itself, but is often not accepted or considered: Of course, plaster surfaces provide resistance to wind forces and roof loads through windshielding and diagonal bracing. The problem of why this fact is so often contradicted is a sum of modern demands on (non-flexible) surfaces, lack of training and experience, and the fact that poor plasters (ie, without good adhesion) meet these requirements only partially. This does not mean that a straw bale wall directly plastered on both sides would break down due to wind forces or loads (no single case is known to me, even in the most adventurous constructions). The problem are the cracks, and craftsmen have almost panic fear of it. Today, when Consumer Protection has decapitated private builders and house owners (we can not take responsibility, even if we want), the responsibility lies with the craftsmen for years or decades. And these protect themselves by multiple safety activities. The carpenter often also has too less knowledge about (good) plastering, because this is not what he is trained for, but he is responsible for the structural integrity of the construction. So if you want a directly plastered straw bale wall you should be able to proof the structural abilities of a good plaster with tests and examples of directly plastered houses. Other possibility is: the reinforcement is achieved by diagonally braced intermediate walls. Plasters are exposed to enormous forces and temperature differences. This should be considered when plastering, especially when they have structural tasks (as in load-bearing straw bale construction) to brace and withstand the wind forces.
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SESSION PLAN S1 - TIPS
Direct Plaster Theory: The Function of Plasters
005 Diagonal Bracing with Clay Infill
We recommend a CUT construction with load-bearing walls with one-sided diagonal planking (raw sawn wood). This also makes it easier to fill the bales (simply slide them up to the background diagonals). The bales are attached to the 4 x 1 8 cm construction with 25 x 25 mm strips/battens. If the lattice is outside (recommended), we install the boards at a distance of 4-5 cm (because wood outside with a μ value above 20 is not diffuse open enough) and fill the interspaces with earth/loam or a mixture of clay and straw (that draws the moisture from the dew point area out to the surface and keeps our straw bales dry in the long term, even if the dew point lies in the straw bale level). A reed stucco is then mounted on the boards (clipped with brackets) and windproofed with at least 2 layers of lime plaster. In this case, we are a hydrophobization of the lime plaster is not absolutely necessary. Inside, the straw bales are plastered directly with clay - without annoying covering the surface of the stands with plaster-groung (reed stucco). For many reasons (building physics, sustainability, residential health, smart construction, self-construction suitability, resource consumption), this externally diagonal CUT construction is the best construction for straw bale walls of one- or two-storey residential buildings for us. If a wooden façade is preferred, another layer of plaster should guarantee windproofness in the rear ventilation level. In this case, we often use a diffusionopen 1 6 mm DHF / DWD board (μ-value approx. 8, similar to lime) on the outside, then the rear ventilation level follows with lathing and counter battens (vertically at least 5 cm) and the wooden façade.
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SESSION PLAN S1 - TIPS
Direct Plaster Theory: The Function of Plasters
U5
006 Air- and windproof Boards as bracing Layers
Whether the bales are directly plastered on both sides or on one side, or additionally diagonally stiffened, depends less on the required fire protection (this can be adjusted with the plaster thickness from F30 to F90 (FASBA tests for fire protection, DE) rather from the requirements of the inhabitants to a wall: Installation of kitchen cabinets, installation levels (electrical, water, sewage, ventilation) and from the wind forces. While single- to two-storey buildings have proved to be structurally stabel enough with directly plastered (load-bearing) straw bale walls without additional diagonal reinforcements, wind-forces and loads in multi-storey residential buildings can be so strong that they are not sufficient for such planking. So it depends on the structural engineer, where he plans to reinforce/brace the building: in a plastered or planked straw bale wall, as a prefabricated inner construction (KLH, brick) or separately from the walls (supporting structure, concrete slab construction). For passive houses with their high demands on air- and wind tightness as well as for prefabricated modules (prefab), the full-surface cladding with OSB (inside) and an diffusion-open outer panel (DWD, UDP, DHF) is quite useful because heat losses are cannot be balanced by a heating system. In this case, the preparation of the surfaces includes the taping of all (blunt) connections of the tongue and groove plates (especially in the corners). This boards must be planked with a plaster carrier. The interior plaster ground is usually Heraklith BM (installation level) or clay board in drywalls; on the outside it is also possible to set higher insulation values with softwoodfiber boards (4-10 cm protect).
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SESSION PLAN S2
U5 – FINISHES
U5
Direct Plaster Practice – Wall Preparation Objectives: Trainees are ... … able to organize building site, materials and tools. … aware of health and safety in relation to other workers, building site, machinery, equipment, PPE (personal protective equipment). … able to prepare the surface of the wall and junctions between materials to receive clay or lime plaster.
Methods:
Practice
Theory
Practical exercises at a workshop or building site, together with relevant theory
Specific preparations related to building services (electrical, heating, water and waste water installation)
Exercises to prepare the strawbale wall substrate include: Filling the gaps to achieve a homogeneous wall to ensure airtightness. Cut the surface of the straw to required evenness. Sweeping or, if possible, cleaning it with compressed air Bridging junctions between different materials using hessian, reed and/or mesh Certifying good fastness of the plaster on a smooth surface Assembling technical details like corner protection, angles, airtightness tape, etc. Protecting building components from plastering spills
Trainer:
Place:
Workshop
Duration: 1 day
Equipment:
Straw for stuffing, stuffing tools, hedge trimmer, reed matting, hessian and mesh, staple machine, personal protective equipment, electricity supply, temporary protective material (spot boards, tape etc.), brush and/or compressor with tools
Documents:
Info sheets: I1 Preparation: remove loose material and achieve required evenness I2 Examples of render related to building services I3 Preparation: junctions between different materials Text sheets: X1
Evaluation:
Multiple choice
Organization:
Have a suitable strawbale wall surface ready. Working space for each group resistant to water and mud preferably with roof above.
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Direct Plaster Practice – Wall Preparation
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SESSION PLAN S2 - INFO
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SESSION PLAN S2 - TIPS
Direct Plaster Practice – Wall Preparation
U5
007 Preparation of the Straw Bale Wall Shaving and Cutting
Straw bales are particularly good plaster grounds when the surfaces are well prepared (if not planked). To achieve the best possible and lasting connection with the plaster, the surfaces of the bales are cut with a (sharp) hedge trimmer. Since this can be a considerable expenditure of force (especially with well pressed bales), short hedge saws (about 60 cm sword) are usually better than long ones. This also makes it easier to cut curved surfaces (as in the case of a round house or vault). It is not only about freeing the surfaces of protruding stalks, but also of smoothing and levelling all the unevenness, ie shortening the entire stalks 1 -2 cm. On these many cut stalk ends, the plaster adheres much better than on the untrimmed stalks covered with a wax layer. Therefore, storing the bales for one year, so that the wax layer disappears by heat, is not useful, since it also increases the moisture sensitivity of the straw bales.
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SESSION PLAN S2 - TIPS
Direct Plaster Practice – Wall Preparation
008 Preparation of the Straw Bale Wall: Stuffing Holes
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A rule of thumb is to fill/stuff the loose straw to the center of the bales (about 1 8 cm deep). So we take as long as possible straw halms from a straw flake (at first always twice as much as we think that fits in the hole), place this tuft centrally over the hole and form a heart: with the small stuffer we push the straws into the middle so deep in the hole, that only about 5 to 10 cm stand out (1 st bend). This should cost us some of strength, otherwise you took too little straw. And these protruding stalks are bent back and stuffed again into the hole (2nd and 3rd bend), this time with the larger stuffer. If we do this on both sides of the strawbundle, a heart shape is created. It is very important that in the end the triple bent stalks neither protrude nor form a new cavity (because we have stuffed the straw too deep). The visible node should lie exactly on the surface. We can push any protruding stalks lightly with the hand into the bale, we cut the crease, fall the short straw back out. In doing so, we use the material's own strength (the strong tendency of the stalks to expand after buckling or compression) to anchor the straw well. If it does not believe, it can try differently, but then should also clean itself at this place. I have often experienced that suddenly plugs of plaster fall from the wall because the straw was not well crammed in these places. This may sound a little complicated, but it is really simple - and a guarantee for a perfect straw surface, which is also very well-suited to be plastered.
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SESSION PLAN S2 - TIPS
Direct Plaster Practice – Wall Preparation
U5
009 Preparation of the Straw Bale Wall: mounting Plaster Grounds
The classic and most favorable plaster carrier in straw bale building (apart from the straw bale itself) is reed stucco. In contrast to reed mats, every second stalk (distance approx. 1 cm) is missing, so that plasters can cling purely mechanically to it. Every 10 or 20 cm a metal wire keeps the stalks together, which should be on the outside of the stucco. We bend the protruding ends of the wire backwards so that no one is injured. For assembly, the stucco-rolls are clamped once at the top of the wall on each wire (20 cm distance) with usually 1 4-1 6 mm deep brackets, then the stucco is tensioned and clipped again after approx. 50-60 cm on each wire. Only then the interspaces are re-clamped every 5-10 cm, whereby the wire stretches and the reed stucco presses to the wall. Overlapping is max. 5 cm, in any case always only up to the next wire (never over). For cutting the stucco we use strong scissors, metal shears or a flex. An additional wire (Gardena planting wire) helps to secure the stalks in case of overlapping or in case of missing or damaged wire. Just put it over the reed and stuck it. Usually, the stucco is mounted on walls horizontally, vertically is only recommended for narrow wooden stands. Other plasterboards on wood components are Heraklith BM (magnesite bonded wood chip panels), soft woodfiber boards (which also insulate), Steico underfloor, glass fiber mesh and - in case of a bathroom - waterproof cellulose-bound Fermacell panels (see also page 11 ).
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SESSION PLAN S2 - TIPS
Direct Plaster Practice – Wall Preparation
010 Preparation of the Straw Bale Wall: Sealing Gaps
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As already mentioned in Tip 002, all natural plasters shrink more or less strongly when dried. The resulting joints to visible (wood) components (window frames, doors, roundwood stands, etc.) must be air and windproof. This can happen (usually with considerable extra effort) after plastering (several times with fine plaster), without warranty. It is much easier to attach plaster strips (apu strips, see upper right) to the window and door frames (self-adhesive) in preparig the plaster ground. These are made of plastic and a thin strip remains visible even after plastering (unless they are covered with paint), but they close such shrinkage joints really tight. Traditional methods include ropes that have been glued to the wooden frames, during plastering the plaster tightly closes the gap to the rope. Or nails (as they are still used in Greb technology today), they form a kind of anchoring of the plaster with the wood. Also the cutting of the wooden frames (rough surface) was sometimes used to have a better mechanical connection. A further method is covering the smooth frames with glass fiber or flax fabric (picture above left). Finally, there are plaster-proof air-tight and windtight tapes (see picture on the left and next page), which stick to one or two sides and thus bridge the joints (such tapes are also used for sealing window frames to the construction). Please take care that windproof tapes (diffusion open) are used outside and air tight tapes (moisture braking) are used inside.
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SESSION PLAN S2 - TIPS
Direct Plaster Practice – Wall Preparation
U5
011 Preparation of the Straw Bale Wall: Taping/Masking Windows & Co
Even if it is a lot of work to cover window and door frames exactly, it makes sense to make straight lines with the tape, where the plaster should end (1.5-2.5 cm plaster thickness including fine plaster): Clay can be still removed also after the drying relatively easily, with lime this is almost impossible. In addition, the sands scratch easily sensitive surfaces. For this purpose, there are tarps for paints with plastic adhesive strips (no paper, which can be undulated with moisture) with a pull-out plastic film, which can then be stretched over the entire window. Since the interior plasters are meant for fast drying, not all windows and doors should be hermetically sealed, but adequate ventilation should be ensured. Even if this means that after the coarse plastering the cover strips are removed and reassembled before the fine plastering. In straw bale building, we are working a lot with natural materials such as untreated or oiled wood, which expands in moisture. For example, if the humidity is too high, the windows or doors can not be opened any more. In this delicate phase (hopefully you will never again have this amount of moisture in your rooms), mold formation may occur with too little ventilation on organic surfaces. Compared to that, a little rain on a straw bale facade is harmless. If it is not covered with a tarp, it quickly dries out again. A lot more damage is caused by insufficiently or non-aerated tarps and foils.
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SESSION PLAN S2 - TIPS
Direct Plaster Practice – Wall Preparation
01 2 Preparation of the Straw Bale Wall: insulating Window Frames
Before the air-tight tape is installed inside, the gaps (usually 1.5 cm all around) between window/door frames and construction wood must be insulated. No, we are not talking about PU foam, but of hemp and flax wool. There are also special hemp knits (calafater ropes) that are firmly pressed into the cavities with a piece of wood or a large screwdriver / chisel (some craftsmen also use a drill hammer). As we are dealing with the lowet insulation thicknesses in the entire house, window frames should be worked out precisely and cavities/gaps avoided. In addition, window frames should be insulated externally. For this purpose, insulation wedges made of flax / hemp, soft woodfiber boards (e.g. Steicofix) or cork are suitable. We have also had good experiences with curled reed mats, and this is also the most favorable/cheapest natural material for this purpose.
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SESSION PLAN S2 - TIPS
Direct Plaster Practice – Wall Preparation
U5
01 3 Preparation of the Straw Bale Wall: Mounting Drop Noses
To prevent moisture transport from the (cement) plaster in the splash water area (30 cm above ground level) into the facade lime plaster, these two plasters must be separated by a horizontal barrier. This droplet is basically an extension of the horizontal barrier between the strip foundation and the base plate of the construction to the outside, so that water can drip off (picture left). The bend dripping nose is at the same time the stiffening of this metal strip. Ideally, zinc, aluminum or stainless steel is used. Galvanized sheet metal is a few euros cheaper but not permanently rustproof if it is not painted. The drip can be attached to the outside of the wooden base plate (with roofing nails) or under it (between foundation perimeter insulation and wood). It then protrudes horizontally to the outside (plaster thickness + 5 mm overhang) and then bends obliquely downwards to the dripped nose. A further possibility is to cover the entire base in the splash water area with stainless steel (figure at the top right), the drip nose is then just above ground level. This is someties used when a bitumen-tarp coveres the gap between foundation and board (passive house), so that the drip nose has to be installed on top of it.
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SESSION PLAN S2 - TIPS
Direct Plaster Practice – Wall Preparation
U5
01 4 Preparation of the Straw Bale Wall: Heating- & Electric Installations
1 – 3: The heating pipe placed in the walls has been proved and tested in many straw bale houses. A copper pipe must be warm to be plastered. It is recommended to fix the pipe with perforated metal tape, or to stamp it in the seam inside the plaster. The heating pipe must be always covered with netting mesh. 4 + 5: Electrical sockets and cable are embedded in clay because of fire prevention, air tightness and its easiness of installating. One approved method consists in mixing 1 part of gypsum and 2 parts of clay, so that the electrician can efficiently proceed in working.
U5 – FINISHES
SESSION PLAN S2 - TIPS
U5
TEST CUT-WAND
Direct Plaster Practice – Wall Preparation
01 5 Preparation of the Straw Bale Wall: Tiles or Tadelakt in Bath Room
IIn the splashwater area, no tiles may be glued to a mud plaster since the joints are not 100% watertight. An existing clay plaster in this area may be e.g. protected from splashing water by a pane of glass placed in front of it. In the spraying area, tiles can only be stuck on conventional moisture boards with tile or flex glue. An alternative to tiles is the tadelakt, a luster plaster of natural hydraulic lime, as it has been processed in Morocco for over 1 500 years. Due to its composition (lime putty - Sumpfkalk, fine quartz sands, dolomite flour, marble sands, porcelain earth, volcanic ash, pigments, etc.), and the special processing technique (compressing and polishing with olive oil soap). Tadelakt can also be used in the splash area or for washing basins. However, it remains diffusion-open and can therefore absorb and return air moisture. Tadelakt can be applied to surfaces such as lime plaster, lime plastered Ytong stones (alpha blocks), lime-plastered fermacell or lime-plastered brick walls. The substrate should not be sucked too much so that the workability of tadelakt is maintained over a longer period of time. Tadelakt cures like lime by the CO2 of the air, but it becomes really hard (for example for kitchen worktops) only after 1 -2 months. Then it is waxed and later cleaned/maintained again with olive oil soap and/or wax, acids of conventional cleaning agents destroy the surface.
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SESSION PLAN S3
U5 – FINISHES
U5
Direct Plaster Practice – Clay Mix Preparation Objectives: Trainees are ... … able to organize building site, materials and tools. … aware of health and safety, in relation to other workers, building site, machinery, equipment, PPE (personal protective equipment). … able to prepare clay samples for the several different layers. … able to choose the appropriate mixture from the samples. … able to prepare clay mixtures for the several different layers.
Methods:
Practical exercises at a workshop or building site together with theoretical support
Practice
Theory
Different materials that compose a mixture and how they interact
Carry out experiments to test the quality of the clay soil. Prepare different plaster mixtures for a panel of samples with different ratios of clay, aggregate and fibre. Assess the samples for resistance to abrasion, cracking and general durability.
Trainer:
Place:
Workshop
Duration: 1 day
Equipment:
Samples of clay soil and sand and ready to use clay mixture, short straw fibres, tools and equipment for plastering, electric mixer, personal protective equipment, water supply, electricity supply
Documents:
Info sheets: I1 Origins of clay soils and testing I2 Ratios to prepare samples Text sheets: X1
Evaluation:
Multiple choice
Organization:
Have a surface prepared to receive the samples. Have a panel of samples with the same mixtures already dry (prepared 1 week before). Working space for each group resistant to water and mud preferably with roof above.
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SESSION PLAN S3 - INFO
Clay Plaster - Main Properties
U5
COMPOSITION/FEATURES:
SAND
SILT
CLAY
The clay is characterized by its grain composition. Each grain fraction has its own characteristics, which are the properties of the clay. Example: 10% clay is sufficient to give the clay plasticity and Cohesion.
PLASTICITY: In the plastic state the clay can be treated without deformation, fracture or cracks. These property is important for the processing of objects, the shaping of stones or the cleaning. COHESION: All components are bound together. These binding properties arise in two phases:
Phase 1 : The clay accumulates water (from 20 to 30% by volume, according to the soil type), the clay begins to swell. This process is slow and takes time. Phase 2: The clay dries, the clay particles reduce their volume and bind the components which are finally completely bonded together in the dry state. COMPRESSION:
The clay can reduce its amount of pores in the moist state under the action of pressure. The water plays the role of the lubricant between the grains and thus enable them to rearrange one another to a lower volume. Depending on the soil type, the compaction is more or less important. Example: - clay soil: max. Compression = 2,000 kg / m³ - sandy soil: max. Compression = 2,500 kg / m³
COLOUR: The clay contains colored sands and its own natural color pigments. The most famous pigments are iron oxides, which give the clay a color spectrum from red to yellow. The ocher tones are strongly colored fine earths, which are used for the production of plasters and paints.
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Clay Plaster - Preparation
SESSION PLAN S3 - INFO
U5
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SESSION PLAN S3 - TIPS
Clay Plaster - Preparation
01 6 Clay/Earth Hand Plaster manual mixing
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Loam (clay/mud from the ground) cab be sieved to a dry powder, or is best solved in a pool with water (foil between a strawball ring), until the consistency is viscous and, with 1 part sand (for hand plaster 2 mm, for trowel application up to 3-4 mm grain size) as well as 1 /4 up to 1 /2 volume of chopped straw (from shaving the walls), produces a workable plaster. Dry clay powder is easier to process (but also more expensive), it is available in BigBags and is mixed with 1 part of quartz sand as well as 1 /4 to 1 /2 volume of straw chunks for the first base plaster layer on a tarp (or in a mixer, see right page). The clay powder is best mixed first dry with the sand, then water and straw chunks are added. Ev. check with plaster samples, if not more sand can be mixed. This mixture is well mixed approximately 10 to max. 1 5 min (with feet, hands or a mortar-picker) and finally formed into balls. These should not be too moisty, so that they still keep their form as balls on the foil. With these "Cob" balls you can plaster directly, squeezing/pressing hard and smudging on the straw surface, if it doesn´t glue, add some water (dipping hand plaster in the water briefly). The advantage of such a relatively dry mixture is that a thickness of 1.5 to 2 cm can be applied directly to the first layer (what remains on the wall the same day, will also not fall down later). The first spot can tolerate a little more water, then the next is added on the edge of this plaster spot (if possible without further water addition). The less water is added, the thicker the possible application layer and the less cracks will occur.
U5
U5 – FINISHES
SESSION PLAN S3 - TIPS
Clay Plaster - Preparation
U5
017 Clay/Earth Hand Plaster Compulsory Mixing
Hand mixing is only recommended if sufficient helpers are available (workshop) or the surfaces to be plastered are small (up to 100 or 1 50 m2). For larger plaster areas it is recommended to rent a compulsory mixer. Compulsive mixers with around 300 liters of capacity and 3 rotating arms ideally mix the dry clumpy clay with sand and chopped straw (mixing time also 10 - 1 5 min). It is also practical that the opening is below and therefore the finished clay plaster can be filled directly into a wheelbarrow. The less water is added, the thicker the first plaster layer can be applied. And here, too, it can be checked with plaster samples how much sand the soils can tolerate, in order to have a good adhesion directly at the straw. The more sand, the less cracks will occur, even if they do not play a role in the base plastering. If a first layer is applied and dry and forms a solid base, additional layers can be mixed with more sand (2-3 parts, make plaster samples). These additional plaster layers can then also be thrown to the wall as balls (by hand - see picture left) or plastered with the trowel.
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SESSION PLAN S4
U5 – FINISHES
U5
Direct Plaster Practice – Clay/Earth Base Coat Objectives: Trainees are ... … able to organize building site, materials and tools for plastering/rendering. … aware of health and safety correlated to other workers, building site, machinery, equipment, PPE (personal protective equipment) and of issues specific to working with clay. … able to explain the structure of a clay plaster/render with its several layers. … able to apply the first base coat of a multilayer plaster/render. … able to apply the base “filling layers” to make the wall even. … able to apply a reinforcement mesh.
Methods:
Practice
Theory
Practical exercises at a workshop or building site together with theoretical support How and why to create a first layer for fastness of the plaster/render on the straw The structure and composition of clay multilayer plaster/render with their different thickness Drying timings of the different layers and ventilation procedures to ensure drying Connection between layers: texturize and wet the surface The protection of a drying plaster/render from weather conditions Applying a clay slip by hand or using a mechanic spray. Applying base layers with clay and straw to achieve an even wall. Reinforcing by applying mesh. Checking the thickness to guarantee bracing function as load bearing material Checking good execution with a minimum thickness to guarantee fire protection, airtightness, water resistance, acoustic insulation and protection against rodents and insects.
Trainer:
Place:
Workshop
Duration: 1 day
Equipment:
Samples of earth and sand and/or ready to use clay mixture, straw fibre, tools and kits for plastering, electric mixer, personal protective equipment, mesh, water supply, electricity supply, waterand dirt-tolerant settings
Documents:
Info sheets: I1 Power point: X1
Evaluation:
Multiple choice Practical exercises evaluation
Organization:
Have a strawbale wall surface with the different coats ready for the next layer (preparation during 2 previous weeks). Working space for each group resistant to water and mud preferably with roof above.
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U5 – FINISHES
Direct Plaster Practice – Clay/Earth Base Coat
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SESSION PLAN S4 - INFO
U5
U5 – FINISHES
SESSION PLAN S4 - TIPS
Direct Plaster Practice – Clay/Earth Base Coat
U5
018 Clay/Earth - the Mix makes the difference
In order to ensure that the base coat is not so severely cracked during drying and forms a stable layer on the (flexible) straw surface, fibers (usually hemp, flax) are added in machine-ready finish plasters (1 part clay, 2-3 parts sand). The flush plaster can be applied with a hand-held mortar sprayer or (more efficiently) with a clay plastering machine. A glass fiber fabric is usually embedded on the surface. If handplastered, short straw chopsticks (for example, from shaving the walls) can be added (not usable for clay spray machines). In volume, a mixture of 1 part clay, 1 p. sand and 1 /4 - 1 /2 p. straw fibers (max. 3 cm) can be processed (compulsory mixer). For easier processing, the straw fibers are wetted in water (at least 1 hour). The mixture will always depend on the clay and the sand used (grain size 2 to 4 mm). Therefore, it is recommended to make plaster samples beforehand. With this mix very thick layers (10 to 20 mm) can be applied directly to well-shaved and compressed straw bales, which can then be straightened (compensating layer). A plaster grid is not absolutely necessary with a homogeneous base (without wood parts), but at least parts of a mesh are recommended around window-corners. If the straw bales are badly pressed and the surface can be easily pressed (and only then), it is advisable to apply a mud sludge/preplaster or to spray it better (hand-held mortar sprayers), which stabilizes the straw surface for applying the base plaster). Attention: If it is too thick (too less water, usually 6 p water, 1 p clay), it acts as a separating layer! It must be dry before the surface plaster can be applied.
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U5 – FINISHES
SESSION PLAN S4 - TIPS
Direct Plaster Practice – Clay/Earth Base Coat
019 Spray Plaster Machines and Tools
While professional clay plastering machines (upper right) are usually not to be rented (only together with a professional clay plasterer), there are smaller mortar sprayers, which are also suitable for clay plasters. These can, of course, be used to inject far less square meters/time and the material has to be specially prepared (compulsory mixer) and transported with the wheelbarrow on site. The compressed air funnel gun (lower left, from around € 24, -) with 6l capacity is suitable only for clay sludge (preplaster) and colors (or lime wash). With the manual plaster-thrower (left center), a (fine) top plaster can be applied, but it also requires more muscle power (prices between € 40, - and 70, -). Ultimately, this device is also suitable for clay sludge. With the compressed air mortar syringe (on the upper left), however, it is also possible to apply a clay plaster (also a lime plaster), here the capacity is also limited to 6-7l and the material has to be mixed separately. With a price of around € 270, this is a very useful entry-level device that can be used to make a lot more (30-40) m2 / day than with a hand plaster (1 5-20 m2). A professional clay plaster sprayer sosts for about € 7.500,- to 1 3.000,- mixes the material itself and transports it over the hose also over further distances (10-20 m). A professional clay plasterer with 1 helper can spray between 100 and 1 50 m2 of clay plaster (one layer of about 1 cm) per day. The only sad thing about it: the device can only tolerate specially prepared premixes and no coarse fibers.
U5
U5 – FINISHES
SESSION PLAN S4 - TIPS
Direct Plaster Practice – Clay/Earth Base Coat
U5
020 Clay Plaster Tools
These tools are suitable for clay plaster: Triangular or square masonry logs (2,3l), pointed trowels (4l), Venetian logs (5,6r), smoother (1 r, 6l), friction board, felt board and sponge board (9,10r) (8l, 2r). The surfaces can be smoothed with the trowel, rubbed with the wood (9l) or plastic board (10l), swirled or felted (1 2l). The japanese trowels (3,4r) are the ideal plastering tool (especially for fine plasters). These tools are highly developed and optimized through the centuries of experience in Japan. They are well balanced and are distinguished by the best steel quality as well as an ingenious transfer of the pressure from the handle to the blade. This allows strengthsaving work.
Base Plaster- (l.) and Top LayerTools (r.) source: Lehm- und Kalkputze (Ökobuch-Verlag)
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SESSION PLAN S5
U5 – FINISHES
U5
Direct Plaster Practice – Clay/Earth Top Coat Objectives: Trainees ... … can organize building site, materials and tools for plaster/render … are aware of health and safety in relation to other workers, building site, machinery, equipment, PPE (personal protective equipment) and of issues specific to working with clay. … are able to apply the finish coat of a multilayer plaster/render.
Methods:
Theory
Practical exercises at a workshop or building site together with relevant theory
The different functions of interior (plaster) and exterior (render) clay finish How to improve weather resistance on exterior clay finish The additives to improve the resistance and how they can interfere with water vapor diffusion The range of decorative possibilities
Trainer:
Place:
Workshop
Duration: 1 day
Equipment:
Samples of earth and sand and/or ready to use clay mixture, tools and equipment for plastering, electric mixer, personal protective equipment, water & electricity supply, suitable working area for wet/dirty work with temporary protective equipment (spot boards, tape, plastic sheeting)
Documents:
Info sheets: I1 Decorative possibilities I2 Stabilization, additives, recipes Power point: X1
Practice
Evaluation: Applying a finish coat to an interior surface Applying a finish coat to an exterior surface Trying out samples with different textures Checking good execution to ensure weathering resistance Trying out additives
Multiple choice Practical exercises evaluation
Organization:
Have a strawbale wall surface prepared to apply the finish coat (preparation during 2 previous weeks). Working space for each group resistant to water and mud preferably with roof above
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U5 – FINISHES
SESSION PLAN S5 - INFO
Direct Plaster Practice – Different Surfaces of ClayTop Coats
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U5
Fine-plaster surfaces can be designed not only as a structural plaster (see right), there are clay plasters with a particularly fine grain, multicolored clay plasters in spatula technology, lime-clay gloss plaster, surfaces in Stuccolustro technology (frescale gloss finish technique), ... (Sgraffito, modeling, clay, stencils, plaster intarsia), you will find details about this in the very recommendable book (from which also the picture above comes) Lehm- und Kalkputze (Ökobuch Verlag Germany) by Irmela Fromme und Uta Herz.
U5 – FINISHES
SESSION PLAN S5 - TIPS
Direct Plaster Practice – Clay/Earth Top Coat
U5
021 Clay structural- or smooth Plaster
For structural top surfaces, the fine plaster must be dried to such an extent that it no longer draws streaks. The rubbing (with the sponge or wooden board) is the standard technique for fine plasters. The surface structure depends strongly on the grain size of the upper plaster, the larger the sands, the more friction marks are visible. The friction boards also make rougher surfaces than plastic trowels, which can also be used for reaming. Smooth Plasers (picture on the right), where the fine sand, which after rubbing the surface, is pressed again under the surface - the surfaces must be much more even. Venetian or Japanese trowels are first used to smooth with light pressure, later you change to plastic trowels with stronger pressure. As a result of the increasing compaction, binders and water are pressed against the surface, which is thereby closed. This creates the risk of shrinkage or even the detachment of the uppermost layers. In addition to time, this also needs the feeling of a fingertip and experience. Therefore the smoothing plaster is almost twice as expensive as a structural plaster.
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U5 – FINISHES
SESSION PLAN S5 - TIPS
Direct Plaster Practice – Clay/Earth Top Coat
022 Clay Paints, Limewash, coloured Clayplasters
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Natural clay paints (upper left, large areas) by Sand & Lehm (lehmputze.at) have been specially developed for the application of clay surfaces. They are a spreadable mixture of clay, clay and sand. No solvent or chemical agent is used in these biological colors. The natural coloring of the clays acts as color pigment. An additional tint with color pigments is possible. Natural clay Clay color only cures by drying. Therefore, sufficient ventilation during the drying time must be ensured. In case of good water absorption of the substrate, the natural clay color is particularly easy to process. These clay paints are not suitable for damp surfaces! Sand & Lehm offers natural pigments (top and right small fields) for the shading of natural clay and clay cream. Other natural pigments and colors are offered by Kreidezeit (DE). Clay plasters stay diffusion open with natural colors and pigments, also with colored clay plasters and limewash. It is important that the moisturizing, health-promoting properties of the clay remain intact. For this reason interior paints from the building market should be omitted or very well checked, because they usually contain methylcellulose, silicones or synthetic resins for faster drying, but this reduces the diffusion openness of the walls more or less strongly (and is usually not mentioned in the ingredient declaration).
U5
U5 – FINISHES
SESSION PLAN S5 - TIPS
Direct Plaster Practice – Clay/Earth Top Coat
U5
023 Creative Clay Sgraffito & Co
If colored fine plasters (or several different colored fine plasters) are applied to the base coat as the finish layer, these 2-3 mm thick layers can also be scraped out with stencils, a so-called sgraffito. It is also easy to create ornaments on the walls (popular motifs are suns and spirals), which can be modeled on the still damp (roughened) surface. Finally, edges can be rounded off or hollow corners can be designed, brick kilns and benches can be plastered organically or creatively. But, of course, plasters can also be applied smoothly and without ornamentation and painted. The more edgy our corners are, the more important is the edge protection. This can be a metal strip (corner guard strip) anchored into the rough plaster or can be achieved by means of a jute strip (10-1 5 cm wide) pressed flat with a trowel into the base plaster surface. We also use flax- or jute-mesh for slightly rounded edges. And for hollow cells we use beer bottles (without label) but also EPS (styrofoam) stencils.
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SESSION PLAN S6
U5 – FINISHES
Session Plan U5-S6: Direct Plaster Practice – Lime Mix Preparation Objectives: Trainees are ... … able to organize building site, materials and tools. … aware of health and safety in relation to other workers, building site, machinery, equipment, PPE (personal protective equipment). … able to understand the difference between air and hydraulic lime. … able to prepare lime samples for the different layers. … able to choose the appropriate mixture from the samples. … able to prepare lime mixtures for the different layers.
Methods:
Practical exercises at a workshop or building site together with relevant theory
Theory
Different materials that compose a mixture and how they interact
U5
Trainer:
Place:
Workshop
Duration: 1 day
Equipment:
Hydraulic lime, air lime, sand and/or ready to use mixtures, short fibres, tools and equipment for plastering, electric mixer, personal protective equipment, water & electricity supply, suitable working area for wet/dirty work with temporary protective equipment (spot boards, tape, plastic sheeting)
Documents:
Info sheets: I1 Lime renderings proportions and colouring Text sheets: X1
Practice
Evaluation: Prepare different render mixtures. Prepare a panel of samples with different ratios of lime, aggregate and fibre. Assess the samples for resistance to abrasion, cracking and general durability.
Multiple choice Practical exercises evaluation
Organization:
Have a surface prepared to receive the samples. Have a panel of samples with the same mixtures already dried out (done before with enough time for drying). Working space for each group resistant to water and mud preferably with roof above.
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U5 – FINISHES
SESSION PLAN S6 - INFO
Session Plan U5-S6: Direct Plaster Practice – Lime Mix Preparation
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U5
U5 – FINISHES
SESSION PLAN S6 - INFO
Session Plan U5-S6: Direct Plaster Practice – Lime Mix Preparation
U5
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SESSION PLAN S7
U5 – FINISHES
Session Plan U5-S7: Direct Plaster Practice – Lime Base Coat Objectives:
Trainer:
Trainees are ... … able to organize building site, materials and tools for plastering/rendering. … aware of health and safety correlated to other workers, building site, machinery, equipment, PPE (personal protective equipment) and of issues specific to working with lime. … able to explain the structure of a lime plaster/render with its several layers. … able to apply the first base coat of a multilayer plaster/render. … able to apply the base “filling layers” to make the wall even. … able to apply a reinforcement mesh.
Place:
Methods:
Practice
Theory
Practical exercises at a workshop or building site together with theoretical support How and why to create a first layer for fastness of the plaster/render on the straw The structure and composition of lime multilayer plaster/render with their different thickness Drying/carbonating timings of the different layers and tending (control of humidity, exposure, ventilation, etc) procedures to ensure drying/carbonating Connection between layers: remove sinter layer, texturize and wet the surface The protection of a drying render from weather conditions The need of having humidity on the wall during drying period Applying a lime slip by hand or using a mechanic spray. Applying base layers of lime with or without fibres to achieve an even wall. Reinforcing by applying mesh. Checking the thickness to guarantee bracing function as load bearing material Checking good execution with a minimum thickness to guarantee fire protection, airtightness, water resistance, acoustic insulation and protection against rodents and insects.
U5
Workshop
Duration: 1 day
Equipment:
Hydraulic lime, air lime, sand and/or ready to use mixtures, short fibres, tools and equipment for plastering, electric mixer, personal protective equipment, water & electricity supply, suitable working area for wet/dirty work with temporary protective equipment (spot boards, tape, plastic sheeting)
Documents:
Info sheets: I1 Lime plaster building site example Holland Power point: X1
Evaluation:
Multiple choice Practical exercises evaluation
Organization:
Have a strawbale wall surface with the different coats ready for the next layer (done before with enough time for drying). Working space for each group resistant to water and mud preferably with roof above.
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U5 – FINISHES
SESSION PLAN S7 - INFO
Session Plan U5-S7: Direct Plaster Practice – Lime Base Coat
U5
U5 – FINISHES
SESSION PLAN S7 - INFO
Session Plan U5-S7: Direct Plaster Practice – Lime Base Coat
U5
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SESSION PLAN S8
U5 – FINISHES
Session Plan U5-S8: Direct Plaster Practice – Lime Top Coat Objectives: Trainees ... … can organize building site, materials and tools for plastering/rendering. … are aware of health and safety in relation to other workers, building site, machinery, equipment, PPE (personal protective equipment) and of issues specific to working with lime. … are able to apply the finish coat of a multilayer plaster/render.
Methods:
Theory
Practical exercises at a workshop or building site together with relevant theory
The different functions of interior (plaster) and exterior (render) lime finish How to improve weather resistance on exterior lime finish The additives to improve the resistance The range of decorative possibilities
U5
Trainer:
Place:
Workshop
Duration: 1 day
Equipment:
Hydraulic & air lime, sand and/or ready to use mixtures, tools and equipment for plastering, electric mixer, personal protective equipment, water & electricity supply, suitable working area for wet/dirty work with temporary protective equipment (spot boards, tape, plastic sheeting)
Documents:
Info sheets: I1 Whitewashes and limewashes Power point: X1
Practice
Evaluation: Applying a finish coat to an interior surface (plaster) Applying a finish coat to an exterior surface (render) Trying out samples with different textures Checking good execution to ensure weathering resistance Trying out additives
Multiple choice Practical exercises evaluation
Organization:
Have a strawbale wall surface prepared to apply the finish coat (done before with enough time for drying). Working space for each group resistant to water and mud preferably with roof above
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SESSION PLAN S9
U5 – FINISHES
U5
Cladding Theory Objectives:
Trainees are able to … … explain the basic functions of cladding. … explain various methods and materials for cladding, work out advantages and disadvantages of each and address important concerns of the methods. … explain several types of cladding.
Methods:
Theory
Lecture /Talk Explanation Group work on prepared samples (in workshop) Presentation of results of groups The different functions of cladding: Fire protection Weather proofing, water shedding Wind tightness (outside) Ventilation provisions Humidity regulation, permeable qualities in relation to humidity (liquid, gas) Structural performance Rodents and insects protection Design and decoration Acoustic performance Electromagnetic waves radiation performance Structural function and physics of different ways of mounting systems, barriers and planking and how they are applied to construction properly. The different materials for cladding and how they are selected, based on the defined requirement The most efficient and proven methods of applying, conserving and maintaining cladding systems How to ensure windtight layers are not compromised by junctions, fixings or building service penetrations Understanding documents and drawings explaining the application of claddings Organizing the building site, checking the condition of scaffolding, materials and tools according to the topic Calculation of the quantities of materials needed
Trainer:
Place:
Classroom
Duration: 1 day
Equipment:
Beamer (projector) Flip chart and pens Copied info sheets and text sheets Samples of suitable systems
Documents:
Info sheets: I1 Cladding examples Text sheets: X1
Evaluation:
Multiple choice
Organization:
Prepare copies of info sheets. Samples / plans to make training sketches in group work.
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U5 – FINISHES
SESSION PLAN S9 - INFO
Cladding Theory
S-House with larch wood facade in front of ventilated clay-plastered straw ball wall.
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S-House Böheimkirchen (GrAT): The larch wood planks were oiled (AURO) and fixed with "wooden dowels", so that the building-waste can be sorted separately.
U5
U5 – FINISHES
SESSION PLAN S9 - INFO
Cladding Theory
U5
Passivhauskindergarten Ziersdorf: natural grey Cladding (layed horizontal)
Winery Dross (Bauatelier Schmelz): Facade made from painted plywood-boards and sliced wine barrels.
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U5 – FINISHES
Cladding Theory - Inspiration
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SESSION PLAN S9 - INFO
U5
Row A) Planked Facade with burnt wood (1 : NRJA, Latvia; 2/3/4: House in Divcibare / EXE studio) B) Cladding with view through (5: wespi de meuron romeo architekten; 7: IPT Architects, Howe Farm) C) Organic Facade (8: Deubzer König + Rimmel / Audimax Munich; 9/10: Strohboid/TU Graz)
U5 – FINISHES
SESSION PLAN S9 - INFO
Cladding Theory - Inspiration
Row D) Wood shingle facade (1 2: Andrew Maynards Arch; 1 3: Students of ETH Zurich, Pavillon) E) Cladding doors for opening (1 4/1 5: Tekapo Bach | NOTT Architects, 1 6: FAM Arch. + Feilden+Mawson; 1 7: Straw behind Plexifacade (Sarah Wigglesworth); F) 19: Straw behind brick facade (Jules Ferry Residence); 20: Vertical Garden by Patrick Blanc (Quai Branly Museum)
U5
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SESSION PLAN S10
U5 – FINISHES
U5
Cladding Practice Objectives:
Trainees are … … aware of health and safety in relation to other workers, building site, machinery, equipment, PPE (personal protective equipment). … able to organize building site for cladding. … able to use various materials for cladding using suitable installation. … able to use tools and equipment for fast and safe application. … able to install cladding support maintaining the qualities of the wall structure. … able to install cladding construction with the required functions like ventilation, insect prevention, conservation, etc. … able to coordinate working partners on a building site. … able to choose the most efficient and proven methods of applying cladding.
Methods:
Trainer:
Place:
Workshop
Duration: 1 day
Equipment:
Training ground tools, electric screw drivers, kits for planking materials, brakes and barriers, tapes, glues and foams, screws, nails, clamps, electricity supply, personal protective equipment, flip chart
Practice
Theory
Practical exercises at a workshop or building site together with theoretical support Different technical systems and range of options for: Ventilation and water drainage, Weather protection, Mounting systems, Fire protection (along elevation), Wind tightness (outside), Different materials for protection against animals / insects, Design Structural function and physics of different ways of planking and barriers and know how they are applied on supporting construction properly. How the wall must be prepared for the application of different cladding materials. The appropriate conservation methods for the different cladding materials.
Documents:
Info sheets: I1 Supporting construction I2 Ventilation provisions I3 Massive wood cladding Text sheets: X1
Evaluation:
Multiple choice
Check if the support is ready for cladding application Applying different types of barriers and planking materials Checking good execution to guarantee fire protection, airtightness, water resistance, acoustic insulation and protection against rodents and insects Group discussion comparing the different solutions for most efficient and proven methods
Organization:
Prepare a section of a strawbale wall (including connections between different materials i.e. foundation, wall, roof, …). Prepare tools and kits for different systems (planking, brakes, barriers, …).
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U5 – FINISHES
SESSION PLAN S10
Cladding Practice
Rhombus-battens on 1 x2 inch battens (under-construction 40-60 cm distance) Material: Larch Surface treatment: untreated/raw Quality: with knots Thickness: 21 mm Width: 68 mm Length: 1.980 mm
min. 1 5 mm distance between each Rhombus-Batten
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U5
STEP – Straw Bale Training for European Professionals UNIT 5 – Finishes (201 7) Editor: ASBN, Tips/Authors: Herbert Gruber, Helmuth Santler (ASBN), Anton Auer, Irmela Fromme, Uta Herz, Isabelle Melchior; Co-Workers: BuildStrawPro-Team (Erasmus+ Project); Design & Photos: Herbert Gruber; add. Photos: Minoeco, Ökobuchverlag, provided by Architects. Illustrations/Icons: Michael Howlett (SBUK) This Handbook bases on the Handbook by the LeonardoGroup STEP (201 5)
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