How to Control Moisture Under Your House

What You'll Need
Heavy plastic sheeting
Heavy waterproof tape
Drainpipe deflectors

It is extremely important to control moisture underneath a house. Without controlling the degree of moisture in the foundations of a building, major damage can eventually occur. Structural deterioration will also occur, eventually causing major problems for the entire building. Getting control over moisture under a house is, fortunately, not as difficult as many people think. There are varying methods to help control moisture buildup depending on the type of house and the environment in which it is situated. There are also some common and effective methods which apply to virtually all houses and are well within reach of the average DIYer.

Step 1 – Improve the Existing Drainage

Improving the existing drainage for your house is the best way to start. Find all of the downspouts and find out where the water is going during rain. If the water coming from the downspouts is building up directly below the end of them or in another nearby location, this could be your problem. You will need to use drainpipe deflectors to remedy this. Ideally, you should check this during rainy weather.

Drainpipe deflectors come in various different shapes and sizes and are used to send the water elsewhere. Buy and install the deflectors for all of the problem downspouts so that the water will be rerouted to drains or ditches. The deflectors can also point out onto areas which slope downwards away from the house, though it is usually best to avoid having them pointed towards areas of paving. Once you have installed the deflectors, survey their performance next time it rains. You may need to tweak them a little by moving them to one side or extending them to be more effective.

Step 2 – Install More Drainage

Adding more drainage to your house can help to deflect water which runs down a slope towards your house. One such drainage solution that you can easily construct yourself consists of 1-foot deep trenches containing gravel followed by sand and then turf. This will help to trap a lot of water until it soaks into the ground or dries up.

Step 3 – Create a Barrier

Heavy plastic sheeting can be used to line the ground below porches and crawlspaces around your house. Make sure that the plastic sheeting is connected together with waterproof taping. The sheeting should then be anchored in place. You can use rocks from the garden to do this. Sand is also perfectly adequate. This plastic sheeting installation will act as a barrier preventing vapor from rising from the ground and causing excessive moisture buildup beneath the house. To make sure that it works effectively, always check to see that it is still held down properly after there has been a heavy storm or a particularly high amount of rain. Sometimes, you may need to make some minor repairs to the vapor barrier.