The answer is yes, it can. Venetian polished plaster is a stronger alternative to other types of plaster finishes but Just like any other plaster it can crack but it is important to understand why. This article "Does Venetian Plaster Crack?" will explain the different types of cracks and the potential reasons they would appear, what measures can be taken to prevent cracks from appearing and what action to take if you Venetian polished plaster surface has cracked.
The most common reason that will cause Venetian plaster to crack is movement in the substrate. i.e the background that the polished plaster has been applied to is moving or has shifted slightly then settled. There are other reasons that will cause cracks such as if the plaster has dried out too quickly or the correct mixing procedures have not been followed however these reasons are uncommon.
Reasons for movement in the substrate:
Reasons for plaster drying out too quickly:
Hairline cracks in Venetian plaster are caused by movement in the substrate either from shrinkage, settlement, poorly constructed substrates or highwinds.
They are not cause for concern but are unsightly and would need to be repaired to bring the polished plaster application back to it's former glory.
'Crazing' Cracks or micro fissures:
Crazing or micro fissures cracks in polished plaster are caused by incorrect mixing procedures, not priming the substrate prior to application of polished plaster or excessive heat or background suction which has caused the moisture to evaportate rapidly from the wet plaster .
Rare but these types of cracks could affect the structural intergrity of the polished plaster finish and over time could begin to flake and peel. These cracks would need assessing prior to being repaired to bring the polished plaster application back to it's former glory.
There are multiple reasons why cracks can appear and multiple ways to reduce the risk of cracks appearing in Venetian plaster applications but all have to be considered prior to the application of the plaster. Unfortunately there will be instances where elements out of our or the main contractors control will cause the plaster to crack such as high temperatures, high winds etc. but we will focus on what we can control. As mentioned the main cause for cracks to appear is movement in the substrate.
This is the element that we have most control over, if a substrate isnt constructed properly cracks could appear.
We have substrate spec sheets in PDF format for each type of substrate build up, these inluded Plasterboard, Solid plastering & Previously Decorated These documents contain detailed instructions on how to construct and finish each type of substrate prior to the application of Venetian plaster. They also include details of acceptable tolerances and images of unacceptable finishing. If you require a specific substrate spec sheet from Marmo please get in touch.
Anti-crack fibre mesh can be used to strenghten existing or old substrates where there have been cracks previosuly. The anti-crack mesh system is applied directly to existing walls or ceilings and buried into our basecoats of plaster, effectively tying the whole substrate together in one continous mesh. This will greatly improve the strength of the substrate and reduce the risk of cracks appearing in the future. In most cases it will even stop existing or re appearing cracks from returning in the venetian plaster finish.
Does Venetian Plaster crack? Yes, it can but as explained in this article there can be lots of reasons for cracks appearing in venetian plaster. It is important to take the necessary steps whilst constructing new substrates or preparing existing or previously decorated walls to ensure the best possible chance of preventing cracks from appearing.
If cracks have appeared, they can be fixed but this must be carried out by a specialist contractor.