How to Eliminate Moisture Behind Your Basement Vapor Barrier

Basement vapor barrier sheets and paints are intended to be used as a way of ensuring that moisture does not get into the walls and ceiling of your basement. However, it is sometimes true that water vapor will become trapped behind the barrier, creating a layer of moisture under the floor. This moisture can then slip through small air holes in the barrier, and penetrate the home. There are a few solutions which the homeowner can try themselves to ensure that moisture remains behind your vapor barrier. One solution is to use a different product to prevent the moisture from building up, while another is to install some insulation in order to reduce the possibility of moisture building up in the first place.

Step 1 - A Coat of Paint

The best method of preventing moisture from becoming trapped under a plastic sheet is not to have the sheet in the first place. Instead, consider installing basement vapor barrier paint. Rather than having sheets, which will never be 100 percent watertight, applying paint means that you can significantly reduce the likelihood of air holes. This liquid is applied, usually as a primer, to the bare boards of the basement, and rather than having to have a layer of mortar underneath the plastic, you prevent the moisture from even laying on the top of the boards. Apply the paint in a steady, even stroke, avoiding air bubbles, and ensuring that all parts of the basement are covered.

Step 2 - Another Coat

Once you have finished with the barrier paint, you will need to apply a general coat of paint, which can be done using the same paintbrush. This will help to protect your barrier paint, and also ensure that your basement has an attractive color scheme. Leave the paints to dry completely before entering the basement on a regular basis.

Step 3 - Raise the Barrier

Another solution to the problem of moisture penetrating vapor barriers is to lift the sheeting up off of the floor. This is done by construction a timber frame on top of the concrete floor, and then installing the sheeting on top of this. This will help to keep the sheeting from coming into contact with the moisture, and also provide a layer of insulation by trapping air between the concrete and the sheeting. Place your timber lengths into box-frames, which should be no larger than the width of your vapor barrier sheets. Nail your sheets to the frame, taking care to ensure that the barrier is flush with the wood frame. Continue throughout the basement. Finish by adding a layer of caulk, and then installing boards or flooring above the sheet.

Step 4 - Insulation

Insulation is another good idea for those able to manage it. Insulating foam will help to keep moisture away from the walls. Use a waterproof material which can dry quickly, and use it to cover the bases of walls, and any pipe or duct work which is cold. Take care not to cover hot water pipes, as these can become over heated. A layer of insulation between the sheeting and the floor of the basement will also keep moisture out.