I can’t stress enough the importance of having a basement thoroughly inspected. Think about it –a hole dug deep in the ground can easily fill with water. Making sure that you do everything possible to keep the basement dry is crucial to the well-being of your house.
Damp basements can lead to mould growth. Moulds need a variety of conditions in which to grow. They need heat – and there is almost always enough heat in a basement. They need a “food source” which typically in a basement is cellulose such as wood or the paper on drywall. Mould also requires moisture in order to grow – even dampness in the air will suffice. So if you want to reduce mould growth, a dry basement is essential.
Good grading is critical. Grading is the ground around the foundation. Good grading is when the ground slopes away from the foundation so that surface water such as rain and melting snow will drain away from the house. As one cannot direct water onto the neighbour’s yard, a swale (ditch) may have to be created so that the water can flow either to the street or into the back yard. Creating positive grading is usually the cheapest and easiest way to help keep a basement dry and mould free.
Installing a full set of eavestroughing and downspouts is a very effective way to shed water away from the foundation and basement. Today’s eavestroughing can be continuous so that there are no leaky joints. The troughs are solidly secured to the house so that they can survive our winters and the downspouts are large enough to handle large volumes of rain water during a storm.
Yes. Most home owners in Ottawa should be running a dehumidifier in the basement set at between 40% and 60% +/- in the summer. Dehumidifiers are mobile and are on wheels (so they rarely come with the house). They go in the basement because moist air is heavy and gravitates to the basement floor. Warm air can contain more moisture than cold air, so the dehumidifier should be run into the autumn, until the temperature goes down and the dehumidifier stops working on its own.
My rule of thumb is that all cracks in a foundation will eventually leak. This means that all foundation cracks will have to be repaired in order to keep water out of the basement and keep the basement mould-free. Minor cracks can be injected from the inside; larger cracks are usually repaired from the outside of the foundation.