How to Install Moisture Barrier
Browse articles:
Auto Beauty Business Culture Dieting DIY Events Fashion Finance Food Freelancing Gardening Health Hobbies Home Internet Jobs Law Local Media Men's Health Mobile Nutrition Parenting Pets Pregnancy Products Psychology Real Estate Relationships Science Seniors Sports Technology Travel Wellness Women's Health
Browse companies:
Automotive Crafts, Hobbies & Gifts Department Stores Electronics & Wearables Fashion Food & Drink Health & Beauty Home & Garden Online Services & Software Sports & Outdoors Subscription Boxes Toys, Kids & Baby Travel & Events

How to Install Moisture Barrier

How to install a Moisture Barrier How to prevent dampness to walls

There is nothing worse than damp getting into your home. It can cause dry rot and mould and the smell of damp is very unpleasant. There are several reasons for walls becoming damp, blocked guttering, or your house might be built on a flood plain.

The most common problem is during the winter months there is more moisture in the air in the house than outside, and it moves from the inside to the outside of your home through the walls. If the walls are insulated the water may condense with the insulation making it less effective.

In the worst possible scenario the moisture can actually freeze within the walls and when it it melts it stains the walls and ceiling. 

To prevent this happening it is necessary to install a moisture barrier which is quick and easy to do. It will provide a waterproof barrier between the exterior and interior of the house and where there is insulation it is always installed on the warmer wall, the living area side of the insulation.

There are two kinds of waterproof material you can get for a moisture barrier, 6 mil (0.15mm) thick polythene CGSB membrane in rolls 8 or 12 feet wide to match the wall height, or reflecting moisture barriers which are foil-backed kraft paper in which the aluminium reflects heat back inside the house.

These are not as popular as the polythene rolls because they are less resistant, they are offered in narrower rolls and are more complicated to install.

You will need

  • The correct size polythene roll for the wall
  • Sealant
  • Scissors
  • Staple gun and staples

1. Cover the back of all the switches and outlets on the outside walls. Cut a piece of polythene and make a hole in it to run the wires through. Apply the sealant to the back of the electrical boxes and press on to the polythene sheet to seal completely. You will return to these appliances after the moisture barrier is installed on the wall.

There are specially designed electrical boxes for outside walls which have pre-sealed backs so save time.

2.Apply the sealant along the cap and sill plate to which you will be applying the barrier.

3 Stand the roll near the wall in such a way that you can simply unroll it easily along the length of the wall. As you unroll it staple the sheet to the sill, but do not make too many holes in the polythene sheet.

4.Press along the previously applied sealant to seal the sheet to the frame.

The moisture barrier now gives you an insulated wall but plan and install it properly otherwise it could cause mildew growth on the walls and ceiling. If this happens there is no option but to cut open the whole wall to see where the problem lies.

Additional resources:

Need an answer?
Get insightful answers from community-recommended
in Weatherizing & Insulation on Knoji.
Would you recommend this author as an expert in Weatherizing & Insulation?
You have 0 recommendations remaining to grant today.
Comments (0)