Castle Grumello Conservation Project
GRUMELLO DIWINE
Conservation studio+lab a.y. 2014-2015 Prof. Elisabetta Rosina
GDW Group 8
chapter I:
surface
mapping
Cracks
DS 01
Grass DS 02
DS 03
Moss
Lacuna DS 05
Disgregation DS 06
Saxifragaceae DS 04
North facade
1
Detected degradation
Surface mapping
South facade
Diagnostic schedule 01
Cracks
Crack: Individual fissure, clearly visible by the naked eye, resulting from separation of one part from another. The mortar weaknesses lead to few fractures with the potential detachment and lost of parts.
objective
intervention DAMAGE
CRACK
DEFECT
ANTHROPIC FRACTURE
FRACTURE WITH SEEDS AND SPORES DEPOSIT
STRUCTURAL FRACTURE
ORIGIN
UN CORRECT USE OF THE BUILDING
VEGETATION IN THE MORTAR EXPANDS ITS ROOTS
WATER ENTER FROM HOLES AND FREEZES
WEIGHT LOAD
notes warnings
Consolidate the wall structure repairing cracking in the rocks. Prevent further propagation of the phenomena along time closing/filling the existing fractures. 1. Recognise material stratification and its composition. Understand if we are dealing with a single rock, multiple rocks agglomerates... 2. Verify the direction of the fracture propagation checking if it is structural and runs along the wall or if it belongs to the rock’s degradation. 3. Clean the fracture removing vegetation if present wearing appropriate gloves. Dry cleaning blowing with compressed air mortar powder and other residual material left inside. Use appropriate support such as stick with brushing surface in order to not leave possible aggressive materials. 4. Fill the gap with an appropriate material which prevents infiltration of active and passive dangerous actions (vegetation action - water infiltration which freeze during winter ) The remaining wall doesn’t hold anymore an heavy weight thus we probably do not have structural problems. A correct maintenance of the mortar normally prevents this kind of damage. Top rocks are, by definition, the weakest one thus they should be checked more frequently. Stone should keep its original appearance after the intervention.
Diagnostic schedule 02
Grass
Grass: herbaceous plants with narrow leaves growing from the base
objective
intervention DAMAGE
GRASS
DEFECT
GRASS GROWING ON MORTAR
GRASS GROWING FROM SOIL
ORIGIN
AIR BRINGS SEEDS INTO EXISTING FRACTURES AND HOLES
INSECTS ACCIDENTALLY BRINGS SEEDS ON MORTAR SURFACES
VEGETATION SPREADS GROWING FROM SOIL
notes warnings
Remove vegetation and return the building surface to its original appearance, preventing future biological attack. 1. Simple superficial removing taking care about removing roots. Wear appropriate gloves. 2. Clean the surfaces using a special brush with the support of distilled water and alcohol. 3. Remove grass from the closer soil and set a maintenance plan. 4. Fill the holes where roots have easy spots to grow. Regular mortar substitution. The use of glass reinforced mortar helps either structural support and biological attack prevention. 5. Possible application of superficial products which prevent biological aggression. Part of the wall still merges with the soil so the rate of aggression is quite high but not too critical if kept under observation. Regular intervention is probably the only effective application rather spend in expensive materials.
Diagnostic schedule 03
Moss
Moss: Vegetal organism forming small, soft and green cushions of centimetric size. Mosses look generally like dense micro-leaves (sub- to millimetric size) tightly packed together.
objective
intervention DAMAGE
MOSS
DEFECT
MOSS ON THE MORTAR
MOSS ON ROCKS
notes
ORIGIN
WEAKER AND MORE HUMID MATERIAL (ABSORBS AND RETAINS WATER)
PRESENCE OF STAGNANT WATER UNDER KNEE
CAPILLAR HUMIDITY FROM SOIL
HUMIDITY TO THE NORTH
LARGE SURFACE TO EXPAND
PROXIMITY TO THE SOIL
warnings
Remove vegetation and return the building surface to its original appearance, preventing future biological attack specially on mortar which easily disaggregates. 1. Gross removal of moss wearing gloves. 2. Accurate dry removal of residual moss with rigid brush being delicate on rocks to don’t scratch or damage the original material. 3. Clean carefully the residual stains due to the humidity and biological elements left. In this case we would intervene with a soft brush using distilled water and alcohol. 4. Replace mortar if it appears damaged. Moss propagates faster on north sides and in general on shadowed areas. In our case the proximity to the soil and thus to humidity create an advantageous environment for this kind of attack. -
Diagnostic schedule 04
Saxifragaceae
Saxifragaceae: Vegetal organism gnerally growing from the ground or between stones. The Latin word saxifraga means literally “stone-breaker”
objective
DAMAGE
SAXIFRAGACEAE
DEFECT
CRUMBLING OF THE MORTAR
RUNAWAY GROWTH
The Intervention aims to remove the saxifragaceae from the superficial part. Reactivate the strenghness of the mortar as a consolidator/filler between stones. Restore an acceptable aestetich impact on the exterior parts of the wall. Preserve the maximum load of the mortar in term of self weight and % of disgregation. intervention - Manual removing of saxifragaceae with gloves and preventative measure. - Oust debribs with stiff brush depending on the sensibility of mortar (if really damaged, remove all the pieces)(1) - Cleaning with fine powder and air extraction to capture small debris(2) - Biocides to eliminate all the causes(3) - Removal Black crust from the stones nearby (4). notes
ORIGIN
LACKING MAINTENANCE
POOR QUALITY MORTAR
ADVANTAGEOUS CLIMATIC CONDITIONS
warnings
Check all the wall to see where saxifragaceae are starting to grow. Operate in the order (1), (2), (3), (4) to don’t nullify the effects of previous intervention. Be sensible during the phase (1) to remove as less mortar possible, to don’t cause any other damage to the stones nearby. Operate with safety especialy during the phase (3).
Diagnostic schedule 05
Lacuna
Missing part/lacuna: due to the fall and lost of parts. It is used when the dictionary doesn’t present any other possible definition.
objective
DAMAGE
LACUNA
DEFECT
HOLES IN THE WALL
PRESENCE OF EXTRANEOUS ELEMENTS
ORIGIN
FREEZE/THAW CYCLES
IMPROPER MORTAR
LACKING MAINTENANCE
The purpose is restore and replace the missing part of the wall. Preserve the aestetich aspect as similar as possible with the other parts of the wall. Maintan the adjacent elements inalterate and not influenced from the restoration of the Lacuna (future influences). intervention - Cleaning with fine powder and air extraction to capture debris or by the method of biological cleaning (microorganism). - Consolidant dissolved in a solvent (more adaptable to the small cracks) for the mortar nearby. - Insertion of Stone with same typology and shape of the previous one. - Crystal Growth Inhibitors (1). - Oxalate formation (as an exterior film consolidant for scialbatura) (2) - Protective water repellent (3). - Antigraffiti (4). notes
warnings
Operate in the order (1), (2), (3), (4) to don’t nullify the effects of previous intervention. Insert a stone which doesn’t affect the general aestetich of the wall technique. Avoid consolidants susceptible to different temperature (the viscosity shouldn’t change if exposed to the sun!).
Diagnostic schedule 06
Disgregation
Disgregation: little mechanical stresses provoke grains or crystals detachments. It is quite diffuse in the mortar especially on the top and in presence of vegetation.
objective
DAMAGE
DISEGREGATION
DEFECT
LACK COHESION OF THE MORTAR
CRACKS IN THE WALL
ORIGIN
ATMOSPHERIC AGENTS
TEMPERATURE RANGE
ROOTS GROWTH
Scope of the intervent is repair the part of mortar affected by disgregation. Preserve the integrity and position of the stones nearby connected with the mortar disgregated. Restore the integrity of the wall parts affected by the damage. Preserve an accurate aestetich aspect related to the other elements of the wall. intervention - Manual removing of mortar pieces with gloves. - Oust debribs with stiff brush depending on the sensibility of mortar (if really damaged, remove all the pieces). - Cleaning with fine powder and air extraction to capture small debris. - Reintegration of mortar with same typology and aspect of the previous one (more effective product as consolidant and binding). - Biocides -“Lime technique� as filler but also as consolidant (Nano-lime technology). - Sacrifical lime coating notes Pay attention in the cleaning phases to let the new binding tpenetrate all the cracks. warnings Avoid Epoxy Resin (Brittle, viscous, yellowing material)
Moss
Cracks
Grass
Lacuna
Disgregation
Saxifragaceae
North facade
2
reparation
Surface mapping
South facade
GDW
Thank you!!