The rule of thumb is that any moisture reading over 16% is considered damp and needs attention. If your reading is over 20%, you may need to replace the drywall entirely. Walls in homes with healthy humidity levels typically have a moisture reading between 12-15%.
Safe Moisture Levels in Plaster Walls
Ideally, moisture levels in plaster walls should remain between 12% and 15%. Higher levels can cause: Bubbling or peeling paint.
The real question is not whether your drywall is dry but whether the moisture level it contains is safe and appropriate. An acceptable level of moisture content is between 5% and 12%. Even a higher level may not spell disaster if not confined to a small area.
Moisture and Mold In Your Home
Mold will grow in your home with humidity levels over 55% or higher. It can be controlled with a dehumidifier and good ventilation. Dry walls with a moisture level of over 17% may often need to be removed and replaced by a drywall service.
There is no clearer sign of damp than actual discolouration of your walls, ceilings or floors. Whether it's the mark of the damp itself or yellow or brown discolouration, you're bound to spot this sign of damp in your property as it can ruin the look of any property.
Dehumidifiers can indeed aid in drying wet walls. After a flood, leak, or a spell of extreme humidity, damp walls can develop. A dehumidifier removes extra moisture from the air, lowers the humidity, and stimulates evaporation.
Calm down – 20/24% in plaster is not a problem. Readings over that indicate the likelihood of some 'free' water, but if there is really quite a lot of water (say 35% or 60% showing on the meter for example), then this needs investigating.
The general rule is that any moisture reading over 16% is considered damp and needs attention. If your reading is over 20%, you may need to replace the drywall entirely. The walls in your home with healthy humidity levels should have a moisture reading between 12 to 15%.
How to detect moisture behind walls? Moisture within and behind walls can be detected with a pinless moisture meter. A non-destructive moisture meter can accurately locate and measure elevated moisture levels without the need to break the wall's surface material.
If excess moisture is found, the humidity of the room should also be considered. An acceptable level of indoor humidity is generally 30 to 50%, which prevents the growth of microorganisms, such as mold. Excess moisture promotes mold, mildew, fungi, bacterial growth, and possibly viruses.
Moisture can be the number one enemy of drywall; any good drywall service can tell you that. According to Hunker, moisture levels of about 17% mean the drywall is compromised and will need to be replaced.
Exterior waterproofing coats can be applied to the exterior walls to stop water from penetrating the walls. The barrier that a waterproof coat will create will insulate walls and keep out rain and moisture, keeping walls from becoming damp. You can treat dampness in the interior walls by waterproofing the roof.
A quality meter will be highly accurate and have a measurement range of 6 to 30%. It will also provide a way for the user to verify calibration. Cheap moisture meters might promise accuracy, but they'll lack the evidence for it. They won't have any studies to prove their accuracy.
The respiratory effects of damp and mould can cause serious illness and, in the most severe cases, death. The respiratory effects include: general symptoms such as cough, wheeze and shortness of breath. increased risk of airway infections, including aspergillosis (an infection of the airways with the fungus Aspergillus ...
Although interior temperatures and relative moisture are often personal preferences, researchers have found that an average moisture level will typically range between 50 to 60 percent indoors with a desirable temperature between 19°C to 24°C.
While relative humidity can have some effect on moisture levels, drywall is considered to have an appropriate level of moisture if it has a moisture content of between 5 and 12%.
Dry the water damaged walls
Use high-efficiency blowers and dehumidifiers and open the windows and doors. Use fans to increase air flow behind walls and leave them running for at least two days so the studs and flooring can completely dry.
You should be aware that a moisture reading of 0-15% is quite normal and gives no cause for concern. However, moisture readings in excess of 15% indicate the need for further inspection. Levels between 25-30% indicate that there may be water ingress, meaning that remedial work could be required.
Moisture meters help detect moisture spots with possible mold growth. If your MC reading in wood is more than 20%, you may want to check these areas for mold growth. When the MC is above 20%, this is possibly where mold growth can start to happen. Humans have reason to attach negative connotations to mold.
Tape a square of aluminium foil to the wall and leave it there for a day. On inspection, if the side facing away from the wall is wet, you have an issue with condensation. If the inside of the foil is wet, you have penetrating or rising damp.
Use fans to move air around the damp walls. Also use dehumidifiers, which can help remove moisture from the air and walls. Professionals use tools like moisture meters, infrared imaging devices, dehumidifiers and heavy-duty fans. That ensures the walls are truly dry before further repair, painting or refinishing.
But is DampRid as good as a dehumidifier? "While DampRid is nowhere near as rapid or effective as a good dehumidifier, it almost works the same as a poor-performing dehumidifier," says Chris.
Once temperatures drop to around 65 degrees, it's best to turn the dehumidifier off. Doing so will help prevent moisture from freezing on the dehumidifier's coils, which could damage your unit.