DSIT C alex warren

dsit c pneumatic formwork system for catalan roof vaults aleX warren 33193582

timbrel vaulting - low tech mapungubwe south africa

Interpretation

centre,

Peter Rich Architects

summary National Park visitor centre, with tourist facilities and offices. Awarded World Building of the Year in 2009.

analysis • Cheap construction despite apparently complicated geometry.

• Local materials, local labour.

• Easy to construct - in this case unemployed South Africans were trained in the manufacture of earth tiles and in building the vaults.

• No machinery (such as cranes) required, built on scaffolding from hand labour. Tiles are built off site.

• 4 layers of tiles - rotated 45 degrees each time to make the structure rigid and eliminate any gaps. TIle grout joins tiles.

• Elliptic paraboloid geometry is derived from the naturally strong geometry of a sphere.

timbrel vaulting - high tech Free-form Catalan Thin-tile vault block research group

summary This research project presents important advances in timbrel vaulting, made possible through innovation in virtual form finding systems and construction methods

analysis • Rhinovault plugin finds the structural optimum from a user defined set of base curves. It engineers the geometry ready for construction.

• A waffle grid structure provides the formwork (as opposed to a traditional method of 4 intersected timber guide frames). This method provides a greater surface area, making the tiling process easier.

• The waffle grid is made up of cardboard, which was sprayed with water to remove it once the four layers of tiles were in place.

• The cardboard formwork is produced on CNC machinery, but the terracotta tiling is done by hand.

workshop Precedent study terrassa textile mill barcelona spain Lluís Muncunill i Parellada

summary Built in 1908 as a textile factory, the building was converted into a museum of science and technology in 1990. The main industrial space alone covers 11000sq.m, and is naturally north lit.

analysis • Rather than being constrained to a single rectangle of the grid; the roof lights spread across two grid rectangles (6 columns). This means the vaults are longer and so let in more natural light.

• The Catalan/timbrel vaults are also curved in section, increasing the glazing height, allowing more light inside.

• The unusual art deco shape is unique in architecture, but each one of the 154 timbrel vaults is structurally identical.

• Cast iron columns support the tile vaults, raising the roof structure high above the industrial work space below.

eladio dieste study numerous projects, uruguay

summary Uruguayan architect and engineer specialising in large spans with Guastevino vaults, built from brick or ceramic tiles.

analysis • His common theme was low-tech, large span spaces; similar to the construction conservation workshop I am designing.

• As Lluís Muncunill i Parellada (above), most of his structures employ north facing roof lights to offer consistent ambient light in a space • The glazing opening has no straight edges - both the upper and lower arches are curved. This increases the height of the usable space inside the building.

• Usually the elaborate tiled roof structures are tied into concrete columns, often concealed by brickwork. The roof therefore is its own independent structural system.

grasshopper roof eXperiment I wrote this script that joins two arcs into a modular roof system similar to work by Eladio Dieste. This design tool allows me to specify the design of each individual roof light based upon my chosen set of parameters: Width, Depth, Height (of taller, northernmost arch), Height (of lower, southernmost arch - usually flat), Angle of the ‘glazing’, and finally Thickness The most important parameters environmentally relate to the centre point of each arch as these control the quality of light entering the workshop space (below).

Once an individual roof light geometry is created, I can array the geometry in a grid pattern to suit any given roof size.

parameters

poInts

arcs

surface thIckness

glaZIng

grId

vIsualIsatIon

As described, right of page

(X, Y & Z axis) Controlled by parameter inputs

Between POINTS. Rotate function allows me to control the glazing angle.

Surface created between ARCS forming the roof lights. Tile thickness is offset from this.

Located between arcs and allowing for tile THICKNESS.

This controls the number of roof lights, based on 2D rows and column input parameters.

The preview geometry, colour coded to aid clarity.

base geometry

Increased roof lIght

angled glaZIng

Inverse lower arch

The most basic iteration - vertical glazing and a flat base; but still forming double curvature constructable by means of timbrel vaulting.

Increases glazing size and so increasing the amount of light fed inside, but there would be a maximum angle each roof light could be constructed at.

This layout follows the sun’s movement, allowing more ambient light inside because of the light bouncing off the roof north of each section of glazing.

This unusual geometry lets the most ambient light inside by maximising window size, whilst still following the sun’s path from the previous design iteration.

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scrIpt IteratIons Above: further iterations of the Eladio Dieste experiment on the previous page.

Adjusting the input parameters creates a number of possibilities; including lowering the Z height to minus figures, resulting in an inverse geometry that would let more light in to a workshop space below (images 4 to 6).

7

s - shaped roof profIle Eladio Dieste utilised the ‘undulated generatrix’ (s shape gaussian vault) roof profile because it allowed unbroken spans of about 50m for industrial and sports architecture.

The double curved geometry also lends itself to rain water drainage.

Right (7): A section cut through a typical roof using Dieste’s gaussian vault roof profile. The transition between flat and S shape geometry is clearly visible.

poInts (X, Y & Z axis) Controlled by parameter inputs

3 arcs Between POINTS. Two identical flat lines either side of an S shaped profile.

surface & array Surface created between ARCS forming the roof lights. Tile thickness is offset from this.

Left: script shows a side to side (east to west) derivation of form rather than a front to back (north to south) - roofers would tile in this method across the roof from either side.

catalan vault construction Catalan Vaults originated in Catalonia, Spain; and are often known as ‘Timbrel Vaulting’ - ‘timbrel’ translates as ‘tambourine’ in Spanish. When the thin shell of a perfect catenary formed timbrel vault is tapped, it is said to sound like a flamenco player’s tambourine (right).

Catalan vaulting was utilised famously by Antoni Gaudi in Barcelona (right, far) but was reintroduced in the 19th Century by Spanish architect Rafael Guastavino. The construction is still known in the Americas as Guastavino tiling.

The strength in this technique lies in the geometry. Catenary curves (below) are formed, producing the most efficient shape that is as strong as the same structure as if it were to be built from reinforced concrete of the same thickness. The construction process is simple - once the formwork is in place, tiles can be laid be unskilled workers.

flat chaIn

hangIng chaIn

This diagram represents a chain laid flat on the ground, divided into a number of segments for clarity

Created with Kangaroo Physics, this is the same chain as previous but it is hung with the digital physics software properties; forming a catenary (idealised) curve.

One layer of tiles is sufficiently strong enough to support its own weight even compromised during demolition.

First layer of running bond tiles held together with gypsum mortar (plaster of paris)

Second layer of running bond tiles rotated 45 degrees

Third layer of running bond tiles rotated 90 degrees from original on regular mortar mix

25 300 150

Alternative herringbone method offers no structural advantages, just aesthetic.

sImultaneous constructIon

tIle proportIons

The three (or more) different layers of tiles can be laid simultanesouly across the structure until they eventually meet in the centre or highest point of the catenary arch.

A typical Guastavino tile dimension. The important dimensions are the ratios: length = twice the width.

formwork options: tImber formwork (Right, near) The industry standard way of constructing brick and tiled vaults and arch structures. Simple and reliable.

Inverse tImber formwork (Right, far) An option when for whatever reason the formwork cannot be supported on the ground below. Difficult tiling process.

pneumatIc formwork Untested with brick or tiled arch structures, but I believe its potential (diagrammed below) is worth investigating.

timber formwork

worker safety & accuracy

tIle completIon

formwork removal

formwork removal

A series of catenary formed timber arches that support the Catalan tiling above.

Workers (in the past) have lost their lives by falling between the timber formwork. The larger the formwork spacing, the less accurate the tiling; leading to a weaker arch geometry.

Tile workers from different sides meet in the centre. 2 or 3 additional layers are added to strengthen the catenary structure, supported with plaster or mortar in between.

If all the timber formwork arches are not all removed at once, stress points will act on the surface (red circles); which could lead to cracking.

All timber formwork therefore has to be removed simultaneously to eliminate surface stresses. This can be done on a movable surface or automated joints.

inverse timber formwork

worker safety & accuracy

tIle completIon

formwork removal

formwork removal

This alternative method uses the same inverse catenary but is suspended rather than being ground supported.

Workers use the formwork as a guide to lay tiles from the top layer down. There is no anger of falling but accuracy decreases because of uncomfortable working conditions.

Tile workers from different sides meet in the centre (on ladders). 2 or 3 additional layers are added to strengthen the structure, supported with plaster or mortar in between.

The formwork is usually lost in the structure after construction (access it impossible); or the structure can be designed in such a way that formwork may be removed.

If the design allows the formwork removal, there would be no stress points on the tiled arch below because tiles usually sag slightly with gravity; so no cracking occurs.

pneumatic formwork

worker safety & accuracy

tIle completIon

formwork removal

formwork removal

An elastic neoprene rubber (or similar) pneumatic cushion that can be inflated upwards from a flat base.

The pneumatic cushion acts as a literal safety cushion for workers. This surface is easy to tile on as there are no voids, leading to a more accurate (stronger) catenary surface.

Tile workers from different sides meet in the centre. The construction may be faster than with timbrel formwork because the cushion is an easier surface to work on.

As the pneumatic cushion is deflated, the stress forces are spread equally across the surface (no stress points), therefore the risk of cracking is eliminated.

The removal of pneumatic formwork is much easier - the air is simply let out of the elastic membrane and (because it is elastic) it deflates uniformly.

pneumatic formwork airform construction A proposed solution to the post-war housing crisis, ‘Bubble Houses’ were concrete domes formed around an inflatable rubber (neoprene nylon) balloon, buildable in just 2 days. The same single balloon could be used as a guide to construct all the houses in one housing development.

Quick construction and relatively simple materials were the basis for practical low-cost Airform post-war housing that architect Wallace Neff developed in the USA and popularised around the globe in the 1950s.

As well as housing; schools, sports halls, community centres and bespoke holiday villas all utilised airform construction.

wallace neff’s bubble houses Because no carpenters, plasterers or roofers were required, a small bubble house could often be constructed in two days, larger ones in 3-4 days (plus furnishing or any external painting).

Balloons were tied with wire to shape new geometries, and smaller modular structures were often joined together to form larger buildings.

The natural geometric strength of these bubble houses made them hurricane and even earthquake resistant.

Left: images show an Airform house in Pasedema, Los Angeles, USA. The fireplace is located centrally to lighten the space, curved furniture lines the walls and a circular ventilation opening is located in the centre.

WIndow openings have to be cut with rounded corners, as sharp corners weaken the structure.

Above: construction process (diagrammed on page below).

the alternatIve method: InsIde out

Circular trench dug to take the ring foundations of the dome structure.

Pneumatic PVC membrane laid out on site and held in place with steel anchors.

An air blower inflates the membrane, after which a double door (air lock) entrance opening is cut out at the front.

2-3mm moisture resistant glass reinforced polyester is sprayed, followed by a 20mm mixture of synthetic resin and perlite (lightweight aggregate) whilst a hot air blower is used to speed up the drying time.

The pneumatic membrane is deflated and can be used again. The resulting structure is as strong as a concrete shell of the same geometry. Additional rounded smaller openings can be cut out afterwards.

A heavy duty neoprene nylon balloon; which is more commonly used to make dry-suits (heavy duty waterproof wet-suits) is inflated.

A layer of reinforcing wire is spread over the dome and a first layer of gunite (sprayed concrete) is applied by hose.

Once the first layer has dried, a layer of insulation is added and finally another layer of gunite is applied; which is the ďŹ nal external ďŹ nish (which can be painted onto).

The pneumatic membrane is deflated and can be used again. The foundation trenches are filled and additional rounded smaller openings can be cut out afterwards.

Here the neoprene nylon balloon is seen being inflated on its concrete foundation base.

Gunite (commonly known as shotcrete, a sprayed concrete) is pictured here being applied to the outer membrane.

The rudimentary scaffolding here demonstrates just how low budget this method of post-war construction was.

Domed structures are hard to divide with partition walls so modular houses like this example are more livable.

PROS: Weatherproof Construction - the outer membrane means construction within can continue in heavy rain and snow.

Price and speed - cheap labour and quick spraying times.

CONS: Gravity - perlite is fast drying (especially with the warm air blower), but it will tend to drip down and create an uneven surface that needs to be constantly patched up as it dries.

Construction Practicality - an otherwise unnecessary air lock has to be created so workmen can enter the air bubble. This creates the problem of poor air quality for workmen inside.

the worldwIde method: outsIde In

Circular trench dug to take the ring foundations of the dome structure. PVC membrane anchored in place.

PROS: Price - once the balloon had been manufactured, materials (concrete) and labour costs were very low.

Speed and ease of construction - digging a circular foundation trench would typically take one day and spraying concrete another, with a third day drying before painting could take place.

CONS: Gunite construction was patent protected, but desperate for mass produced post-war housing, many contractors tried to copy this method and failed, resulting in a poor construction quality meaning most have now been demolished.

Weather - bubble houses were primarily constructed in dry countries - USA (California), Cuba, Egypt and West Africa; to help the concrete dry.

MODEL EXPERIMENT TILED DOME WITH INFLATABLE FORMWORK Tiled vaulting onto pneumatic formwork has not yet been experimented with in architecture. I researched the Bubble Houses because they come closest, but there was such a demise in Catalan vaulting techniques that the relatively new inflatable architecture has never had time to coexist with the ancient vaulting techniques until now.

For the ‘formwork’ in this experiment I used the top half of a balloon wedged in a circular hole cut out of cardboard to keep its rigidity. It was then simple a case of gluing 1:10 scale tiles around the balloon, creating a dome structure reminiscent of early Moorish tiled domes, but with a hint of the ancient stone settlements found in Ireland.

Traditional Catalan vaulting uses 4 layers of tiles, overlapping at different angles so me sure of no gaps in the structure. However at the scale I was working at, gaps were inevitable; but I used two layers of tiles (vertical & horizontal) to give the model extra strength.

Above: the excavation of the balloon was a strange one. As I burst the top of the balloon through the oculus of the dome, the balloon sucked in on itself, glued at hundreds of intervals. The excavation process was fairly straightforward - peeling it away from the tiles.

At 1:1 scale I would use a tile grout rather than glue (I used glue because of the scale I was working at). Depending on the material of the inflatable (perhaps a neoprene rubber or similar heavy duty membrane), the formwork would not stick to the tiled structure.

I took photographs to try and capture the warmth of materiality inside the tiled dome. Rather than being lit up from inside, I found the best lighting came down through the oculus, which at full scale would create a spotlight at different times of day.

1 - vertIcal openIng

2 - vertIcal beams

3 - cut beams

4 - angled beams

5 - edge beams

This arrangement is simple and would work for construction purposes but would not let as much light in as an angled roof light opening, hence requiring the following developments.

I experimented keeping the beams in the same vertical arrangement and just changing the area that was tiled, but this new angle was shallower and didn’t work with the air beam geometry.

This development idea looks at cutting the beams where the roof structure wouldn’t be tiled, but this creates gaps that makes the air beams structurally quite weak.

This development angles the beams parallel to the angle of the north light roof opening, meaning there would be no excess structure and it would be supported all the way across.

This small development creates edge beams around the back and sides of the structure, enabling it to sit flush with the ground rather than balancing on its ends as previous.

development Images above show the transition from air cushion to air cell formwork for the roof tile work to be laid onto. The possible advantages with air beams rather than air cushions is that they are quicker to inflate and require less volume of air.

Right, near: images show the transitional development between a vertical and an angled roof structure using air beams as a construction guide. The air cell geometry lies parallel to the glazing that sits in front to better support the tiles whilst they are being laid.

MODULAR

modular vs Integrated Right, far: a single module composed of a number (in this case 7) air beams can be used as a guide to construct all of the vault structures on a roof.

A larger integrated solution (page below) would allow a larger workforce to tile the roof structure quicker; but this would require a much larger volume of air to keep it inflated and would of course be so much more expensive to fabricate than a single modular unit.

INTEGRATED

grasshopper script Input parameters

‘glaZIng’ geometry

colour codIng

I have parameterised the depth, width and height of each roof structure, as well as the angle of the north light.

Here I use maths functions to calculate the area between each roof structure and create a plane surface between.

Simple colours make different elements in the preview model more clear, based on RGB colour swatches.

poInts

2 arcs

surface geometry

(X, Y & Z axis points) Controlled by INPUT PARAMETERS

Between POINTS. One flat line at the back and one curved at the front forming the lighting opening

A surface lofted between the two arcs and offset by the tile thickness (4 layers would be approximately 100mm thick)

1 - INTEGRATED AIR CELL FORMWORK

array surfaces I created a grid that approximates the span of my site, and arrayed the SURFACEs along this to visualise an entire roof strcuture using these individual roof light geometries.

aIr cell surface

aIr cell housIng

aIr cell geometry

My air beam radius parameter is plugged into the offset script to create a surface supported by a series of air beams.

The roof light angle parameter intersects this surface to angle each air beam parallel to the glazing geometry.

To house the air beams I created a perimeter edge beam, based on the ARRAY grid that encloses the structures.

The PIPE tool lets me visualise an air beam (air cell) geometry based on expanding the radius of the lines I plug into it.

2 - ROOF STRUCTURES TILED OVER FORMWORK

3 - FORMWORK REMOVED, GLAZING ADDED

model eXperiment roof lIght wIth Inflatable formwork For this second physical model experiment I arched modelling balloons between circular holes cut out of card. This structure was attached to a timber base so the bending force of the balloons wouldn’t lift the card.

I created the roof light geometry by pushing the balloons gradually further into the holes, thus creating the gentle roof slope.

The maximum sun angle in Granada in summer is 53 degrees from horizontal, therefore the roof light angles can be optimised to correspond to this angle (diagram, right). For my model I used soft (to not cut into/pop the balloons) yet strong picture cord to pull back the forms to this angle (below).

53°

Above: construction process, much the same as the dome tiling process.

Lessons learnt: the cylindrical geometry of the air beams results in very little surface area for the tiles to be laid onto. This means the tiling process is quite time intensive, as each tile needs to be manually held in place until the adhesive has dried.

Another problem with this method of construction (that I’m sure would also occur at 1:1 scale) is that the grooves in between the air beams tend to suck the tiles in; creating irregular dips in the arch as a whole.

These dips mean that the roof light would no longer be a centenary arch and so would be structurally unstable.

Multiple air beams encourage tiles to sag into gaps

...whereas an air cushion provides a flat surface

MODEL EXPERIMENT cushions with low points Pneumatic enclosures with low points enable larger, flatter spans and reduce stress at the edges of the structure.

Frei Otto describes them as: ‘among the most economical structures for covering large areas’ If this geometry could be used as formwork for a tiled or bricked Catalan roof structure these low points would become columns, supporting the roof above. The pneumatic cushion forms the optimum centenary arch shape, essentially the inverse of Gaudi’s famous chain hanging form finding experiments.

rhino membrane This software allows me to create a basic grid and select, if required, a number of low points that remain static as the surrounding mesh is virtually inflated.In these two experiments I have visualised (above) single low points and (right) multiple low points that each create a specific shaped cushion.

construction The problem with this method of construction would be that a high pressure air supported chamber would need to be built. Unfortunately this means that it wouldn’t be modular - so whilst it could be tiled over, there would be nothing to support the domes whilst the columns would be being built. The cushion inhibits the construction, so therefore this method would be unbuildable.

model eXperiment membrane rIbbed cushIon Here i heat welded the edges of a PVC plastic sheet and used string to restrain the pneumatic cushion as it inflated.

This imitates a pneumatic cushion being restrained by steel cables, producing sharp valleys that could be used to create the basic geometry supporting a series of tiled vault roof structures above.

CONSTRUCTION SEQUENCE: Cushion inflates with an electric pump as per most other pneumatic membranes.

As the cushion inflates further, the node points begin to restrict the inflation movement of the membrane.

Steel cables reach their optimum form but the air pressure causes the cuyshion to expand between.

InItIal experIment

developed experIment

Initial form finding test - a simple cushion restrained by two crossed lines of wire, producing four identically bulging forms. Although the test worked, the geometry isn’t so apparent with so few cushion bulges.

Developed form finding - the same simple cushion restrained this time by seven crossed lines of wire, producing sixty-four bulging forms of varying sizes; helping to demonstrate this construction more effectively.

Once this form has been acheived, air pressure is maintained whilst the structure can be tiled over.

Once the tiling is complete, the cushion can be deflated and be used for more roof structures.

The larger volume of air in centre of the cushion causes the central node points to swell more than those near the edges.

Below: the valleys created by the cabled membrane - a more elastic membrane would produce smoother valleys.

flat chaIn

hangIng chaIn (Inverse)

flat chaIn grId

hangIng chaIn grId (Inverse)

This diagram represents a chain laid flat on the ground, divided into a number of segments for clarity

Created with Kangaroo Physics, this is the same chain as previous but it is hung with the digital physics software properties; forming a catenary (idealised) curve.

A pneumatic air cushion is essentially composed of numerous chains creating a mesh across the surface.

Once inflated, the chains remain catenary, forming an idealised surface that can be used as formwork. The more mesh divisions (chains), the smoother the resulting surface.

form finding development Gaudi popularised hanging chains as a means for form finding (above). The inverse (mirrored image) of these hung chains provided the catenary (idealised) curve geometries that were used to create his famous vaulted ceiling structures.

Thinking of a pneumatic structures as a series of catenary curves (positive and negative values for the two membranes) rather than a single surface helps visualise how useful air filled structures may be in the form finding process, as well as construction guides.

A non-flexible membrane only becomes catenary once inflated to maximum pressure; but an elastic membrane is catenary as soon as air pressure is pumped in between the two layers. This can then produce a range of idealised engineered forms from the same pneumatic structure, which is the basis behind my Kangaroo Physics experiments.

surface Square geometry from 4 previous POINTS. This acts as the deflated cushion.

physIcs sImulator Here I can control and set physical properties for the inflated material (such as resistance, stiffness, and maximum inflation pressure).

kangaroo physIcs These essentially combine the different elements of the script (surface geometries and forces) and add a timer to approximate the speed of the inflation

kangaroo physIcs Kangaroo software, a plugin in for Rhino’s Grasshopper, allows real time physics simulations.

I have used it to set material properties (such as elasticity, stiffness, minimum & maximum inflation pressures) and apply representative gravitational forces to create the positive and negative hanging chain mesh that is the basis for the pneumatic air cushion skin.

Above: A series of gradually increasing inflation pressures; geometries which can also be achieved by altering material properties (especially stiffness - the resistance to inflation pressure).

Below (and page below): Diagrams show how an air cushion can be inflated and used as a guide for a roof light structure based on an idealised catenary surface geometry.

poInts Four X, Y & Z Points that form the corners of the flat inflatable surface.

mesh generator This essentially turns a single surface into one made of a large number of separate chains that the physics forces can act upon. It also lets me choose static points at the edges.

gravIty controls I choose to set the Z axis (up & down) to control gravity, using a positive and negative value for the two faces of the cushion.

on / off swItch I can turn the ‘physics’ on or off so I can visualise the inflated and deflated surface instantly

smooth mesh I added this section to make the mesh less jagged, approximating the smooth resulting geometry.

elastIc membrane = multIple forms An elastic membrane becomes catenary as soon as air pressure is pumped in between the two layers. This can then produce a range of idealised engineered forms from the same pneumatic structure. Taller roof lights let more light in and shallower roof lights are quicker to build and use less materials. A mixture of geometries may be used to allow more natural light into specific parts of the workshop space.

prevIew geometry This helps me visualise the geometry by adding colour to the different sections (blue & yellow).

as prevIous

curved back Using a pneumatic cushion as formwork has the advantage of creating a curved back; which is structurally more efďŹ cient than a flat angled back created from my previous experiment..

roof angle development The angled plane splits the roof surface on, creating a more efficient geometry that is now parallel to the angle of the Granada sun; allowing the most natural north light inside but no direct sunlight.

cut planes I wrote this section with a number of maths functions linking to initial input parameters, enabling me to split the cushion down to that of the roof.

roof angle By creating an angled plane to split the surface on, a roof angle can be created that follows the geometry of the cushion and is parallel to the angle of the Granada sun.

Input parameter tests Here I am testing how adjusting some of my initial parameters - width, depth and height affect the output geometry - an effect quite evident when looking solely at the output roof structure geometry.

basIc surface

3d surface

This section takes the cut planes (including the roof angle) and applies them to the cushion geometry; creating a new thin surface

I have scripted the thickness of the tiles (in this case, 4 x 25mm = 100mm) and extruded the basic surface.

sImple roof structure

developed roof structure

Using one cushion inflated to the same pressure each time. This creates the same roof structure across the entire roof span.

Using a range of inflation pressures can vary the light levels inside the workshop space, reduce the size of roof lights near existing windows and make the most out of an elastic inflatable surface.

roof structure

perspectIve from flamenco caves

Pneumatically formed Catalan tiled roof structures let only ambient north light into the workshop spaces below. The elasticity of the cushion means the roofs can step down in size using the same formwork.

This diagram shows the roof vaults stepping up in size above the main workshop spaces, and stepping down towards the windows of the adjacent juvenile therapy centre building, so they do not block sunlight

or views to the building they are enhancing. Larger vaults at the front of the building also give it more street presence, attracting attention (tourists) but remaining within the 3 storey height limit for the area.

(maxImum summer sun angle 76.3°) workshop spaces are naturally lIt but roofs are desIgned to not let damagIng & dIstractIng dIrect sunlIght InsIde

A

maxImum summer sun angle 76.3°

protected vIews to the alhambra palace

A 3.2m

2

1

vIews to the alhambra mInImum wInter sun angle 29.4°

1.8m 5

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dead load paths

no dIrect sunlIght In workshop space (all year)

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SECTION AA @ 1:200 1 - Coach Drop-off 2 - Tourist Restaurant Area 3 - Deliveries & Storage 4 - Office Spaces 5 - Outdoor Break-out 6 - Workshop Showers 7 - Entrance Walkway 8 - Therapy Entrance

shaded publIc colonnade

hung textIle solar screen

1 - construct brIck arches

2 - Inflate pneumatIc cushIon

3 - tIlIng layers added

4 - vault process repeated

5 - glaZIng added

Using digital form finding tools that replicate the traditional catenary form finding of Catalonia, allowing for this architecture to becomes affordable/practical once more.

These provide the structure that support the roof.

Elasticated Neoprene Viton membrane lifted up on scaffolding and inflated to a high pressure to create the catenary surface formwork that acts as a guide for the tiled vault structure, and a safety cushion for workers.

As described on previous pages, 3 layers of Guastavino tiles are joined using layers of lime mortar and gypsum plaster.

The inflated membrane is coated in a release agent to prevent tiles bonding to it.

The tiling process is repeated, with the elastic cushion being moved northwards, deflating slightly each time to create varying roof heights. There is sufficient space between the final roof vault and the existing therapy centre for the last roof vault to be laid.

The cushions are deflated, ready to be used in other construction projects or used as training devices in the future workshop spaces below. Glazing is craned into place once the cushion has been removed.

ROOF SYSTEMS IN CONTEXT:

ELEVATED WALKWAY

MAIN FABRICATION WORKSHOP

The open spandrels in the brickwork allow flexible placement of movable, modular walkways on the first and second floors.

These walkways can be used to help construction but would probably be mainly used as viewing platforms, accessed via the plant room (second floor) or the restoration school entrance (first floor).

The largest workshop space, triple height and open plan to allow construction practice of large scale brick & tile Catalan structures. The modular catenary

SECTIONAL PERSPECTIVE @ 1:200 APPROX The Catalan vaulted roof heights and widths vary according to the activities taking place below. The smaller vaults are located above the office spaces

where north light is beneficial but not as important as the workshop spaces, where it is more essential. The primary, central workshop space features the largest roof, reflecting the symmetry of the context.

brickwork system is strong enough to support elevated walkways, gantries and suspended equipment; constructed in a way that celebrates the methods taught in the centre.