What happens if you apply a plaster too thickly?

A common mistake people make is not realising the right amount of plaster needed for individual tasks. This can result in either applying it too thinly or too thickly. While adding an extra layer can sometimes remedy applying plaster too thickly, the consequences of putting on plaster too thick are significant. This blog post will delve into the outcomes of applying plaster too thickly, outlining the potential consequences of this common mistake.

Longer Drying Time and Moisture Retention

The most common and major problem you are going to encounter if you put a plaster on too thick is the longer drying time. It’s evident that when plaster is applied too thick, it takes significantly longer to dry. The curing process of plaster is called hydration, where the water in the mix reacts with the plaster and forms a hardened surface. A thicker layer will retain more moisture, leading to a prolonged drying time. To ensure timely project completion, it’s crucial to avoid applying plaster too thick, which can lead to frustrating delays in the drying process. In addition to a longer time, things can be much worse if the project area does not have proper ventilation. It will increase the risk of mould and mildew.

Plaster Debonding

Another major problem you will face if you put a plaster on too thick is plaster debonding. It will not only ruin your hard work but make your walls appear old and damaged. Additionally, replacing  so soon can be a challenging task. Replastering means more work, more money, and more time. 

Increased Risk of Cracking 

Thick layers of plaster are more susceptible to cracking and shrinkage once they dry. The excessive moisture content within the formation of plaster takes way longer to evaporate, causing tension within the plaster. When the plaster dries and shrinks, this stress can result in visible cracks on the surface. These cracks impact the aesthetic appeal of your walls and weaken the plaster’s structural integrity. While repairing and patching these cracks will be more time-consuming and a complete hassle, it also leads to the need for additional material and time. 

Uneven Surface Finish 

Applying plaster too thick can result in problems with achieving an even surface finish.Thicker layers are more difficult to spread evenly and manipulate. It makes it challenging to achieve a smooth finish and aesthetically pleasing appearance. Also, it leads to a bumpy or wavy surface texture, which will require more sanding, levelling, or re-application of plaster to correct. This entire process will take more of your time, making it impossible to complete the project on time.

More Material Waste

Well, if you end up facing any of the problems mentioned above, you will consider re-application of plaster for a seamless and smooth finish, which no doubt will require more material. Also, if you put a plaster on too thick, you will use more material than you should. While plaster is a cost-effective building material, waste due to applying it too thickly can significantly increase project costs. Also, the additional weight of layers can strain the supporting structure, potentially causing damage or early requirement for repairs in the future. 

More Time Consuming 

The process of putting plaster is a labour-intensive process. Applying plaster in thick layers requires more time and effort. Also, when it leads to the above-mentioned problems, the re-application process will take even longer. In addition to this, it will require additional tools and physical exertion to remove the damaged plaster. All this additional work and time will lead to fatigue, causing inconsistency and a decline in the quality of the plaster application. It will lead to uneven application and an unsatisfactory result, which may not be as elegant or pleasant as you hoped.