Discover the Risks of Using a Dehumidifier to Dry Plaster: Why It’s a Bad Idea
Specialists in masonry claim that environmental variables, whether manageable or not, at work locations can adversely affect the result of plaster drying and its overall effectiveness. This is irrespective of the working methodology or the quality of materials used. Therefore, prior to initiating a plastering project, it’s vital to thoroughly examine the conditions surrounding the job.
If the plaster you apply takes a significant amount of time to dry, you may contemplate using a dehumidifier to expedite the drying process. However, this approach isn’t recommended, as it could result in forcing too much moisture out of the air, eventually causing the plaster to lose water too quickly which could lead to cracking.
Alternately, thin veneer applications, such as standard plaster finish coats, which are roughly around 1/16 and 3/32 inches typically, have a tendency to excessively lose moisture compared to the usual basecoat finish which’s approximately 0.5 and 7/8 inches.
Moreover, conventional basecoat plaster methods necessitate considerable air movement for proper water evaporation once the plaster has set. However, with veneer and traditional plaster finishes, there’s the least requirement for air circulation.
Given the complex requirements of plaster work, it’s clear that maintaining optimal moisture levels (between 60% and 80%) is essential. These levels ensure that the plaster remains in a state of controlled drying, thus minimizing room for errors.
Plaster systems are affected significantly by humidity and temperature throughout application, impacting its performance. Especially in the case of veneer plaster applications.
An exemplification can be seen when veneer plaster is applied to a gypsum base. Due to water absorption from the plaster, the base’s surface paper tends to expand slightly. This results in an outward pressure, causing the panel to bend. After the plaster application dries, it expands further, exerting pressure at the joints of each panel.
When you let the plaster dry normally, the pressure subsides, facilitating slight shrinkage during the drying phase. The silver lining here is that this pressure is ample to ensure the joints remain held together. But if a dehumidifier is used for quick drying, excessive shrinkage occurs, eliminating joint pressure and leading to visible cracks.
For satisfactory plastering, it’s critical for the room’s humidity and temperature conditions to remain standard. The suggested relative humidity is above 50% and temperature, above 55°F.
Low Humidity and High Temperature
Reducing relative humidity with a dehumidifier while maintaining a high temperature causes rapid drying, leading to cracks in the plaster. If a dehumidifier that has a fan is used, air circulation augments, leading to higher drying speeds, resulting in plaster shrinkage and dry out.
Essentially, plaster dryout is when water is eliminated from the plaster application so abruptly that it doesn’t manage to hydrate completely. Therefore, a soft, powdery surface results on the ceiling and walls. The shrinkage leads to visible cracks, thus detracting from the plaster’s quality.
Dryout and shrinkage cracks can be prevented by controlling the workplace conditions. Here are some steps to be taken to ensure right drying conditions for plaster.
Maintain High Humidity Levels for Veneer and Standard Plaster: Do not use a dehumidifier for quick drying. Monitor the humidity levels in the room using a hygrometer and ensure that they are adequate. If the humidity levels are lower than optimal, wet the floor or reduce room ventilation.
Reduce Humidity for Conventional Plasters: These plasters require more ventilation as compared to veneer plasters due to a higher water usage and a thicker basecoat. Open the windows or use a dehumidifier set at 60%-70% humidity level if there are no windows. This will enable mechanical removal of moisture.
Maximize Your Plaster’s Drying Efficiency: The Perfect Time to Use a Dehumidifier
When working in regions characterized by exceptionally high humidity levels, exceeding 100%, a dehumidifier may be employed to regulate the moisture levels to a desirable range of 60% – 80%. This creates an optimal environment for the appropriate drying of plaster.
The accurate hydration of plaster during its setting phase is crucial. Hastily extracting moisture over and above the required limit could potentially jeopardize the commendable outcome of the applied plaster.
Frequently Asked Inquiries
What is the duration required for plaster drying?
Plaster’s drying period is influenced by various factors such as its type, the magnitude of its application, and the existing room humidity. Some variants demand a few days, others span weeks, and some might even take up to a month to dehydrate comprehensively. A room with high humidity levels will extend the drying period of applied plaster. Nonetheless, the slow yet effective drying process ensures that the plaster remains well-hydrated, devoid of any cracks or drying-out incidents.
Is it permissible to utilize a heater for plaster drying?
Heater usage for plaster drying is generally not advisable. Appropriate hydration of plaster during drying is pivotal. Consequentially, heating the surroundings escalates evaporation which in turn inadvertently speeds up drying. The aftereffect is a drying-out situation accompanied with shrinkage cracks, undermining the quality of your finished plaster.
Why using a dehumidifier to dry plaster is not recommended?
The idea of using a dehumidifier to facilitate plaster drying is contentious unless dealing with highly humid conditions. Plaster requires a certain degree of moisture for appropriate drying. A rapid drying process could potentially provoke cracking and compromise the consistency of your plaster application. Maintaining an ideally balanced humidity range of around 60% – 70% could yield commendable results.
Adding interesting nuggets:
Did you know that even though plaster takes time to dry, it starts setting within hours after mixing with water? This property of plaster is what makes it ideal for molding, as it retains the shape while still retaining enough moisture for it not to dry out and crack. Another little-known fact is that colored plaster is not painted. The color is added to the mix before application, ensuring evenly distributed color throughout the plaster. The beauty of plaster is not just in its flexibility and durability, it is also in its complexity.