Owning your own home can be your greatest joy. Unfortunately, when things go wrong, panic often sets in and you may worry about how you are going to fix the problem, how you are going to afford it and who you can trust to help. For standing water in your yard or spongy soil around the perimeter of your home, call in an expert. Royal Work Waterproofing Corp. has been waterproofing basements in Toronto and the GTA for many successful years and can determine if a French drain installation will solve all your drainage needs.
What is a french drain?
Contrary to popular belief, the French drain system was not developed in France. It was named for its Massachusetts creator, Henry French, and gained notoriety in 1859 when he wrote a book on the subject. His invention of the French drain eliminated clogging, which was the main concern of the era. The original design has withstood the test of time and remains basically unchanged. Also known as drain tile or a perimeter drain system, it starts with a trench, often uses a pipe, is filled with crushed rock/gravel and sand, and moves excess water to a sump pump or collection basin where it can safely drain away from the foundation.
How does a french drain work?
French drains are typically placed around the exterior of the foundation and are used to divert water from standing or pooling that can cause structural damage. Similar to a roof gutter where rain water is directed to a downspout, French drains manage water at ground level. The simple design consists of a sloped trench filled with gravel and pipe. As rainwater and other surface water soaks into the ground, it is filtered through the gravel into the pipe and channeled through the trench to a collection point away from the foundation. Occasionally, an existing system may fail, allowing water to infiltrate the foundation. In this instance, an interior French drain system may be installed under the basement floor. The principal is similar to an exterior system with a sloped trench, piping and gravel. The water is re-routed to a sump pump and then transported through pipes to an exterior storm sewer.
How to install a french drain?
While installing a French drain can be done by an industrious homeowner, engaging a professional will ensure the proper equipment, slope and materials are used for optimum performance. The following steps will help you understand the process and anticipate any preliminary work that may be needed:
Step 1 - Dig a trench
A trench should be at least 12 inches wide and 18 to 24 inches deep. A recommended slope of one inch for every eight feet should be used to direct water away from the foundation. It should be positioned below floor level if being used to prevent basement moisture.
Step 2 - Pour the gravel
Gravel placed in the bottom of the French drain acts as a natural filter. It allows the water to drain freely without clogging from leaves, branches or other organic material. The best gravel choices are granite or river gravel as they won't break down over time. The gravel should be one-half inch to one inch in size and line the bottom of the trench to a depth of two or three inches. It should also be washed to prevent dust and particles from blocking water flow.
Step 3 - Lay the pipe
There are two types of pipe that can be used for this purpose. Rigid PVC pipe with pre-drilled holes is more durable and can be snaked or pressure cleaned. Flexible pipe with slits is easier to work with and less expensive. Before laying the pipe, cover the stone or wrap PVC pipe with landscaping fabric to prevent weed and root growth and obstruction. PVC holes should also be oriented downward to allow water to flow from below and prevent clogging. Another suggestion for future maintenance of PVC piping is to attach a joint that remains above ground and accessible as a clean-out.
Step 4 - Backfill the trench
A few options are available for covering the pipe. You can cover the pipe by filling the trench with gravel to grade, use a combination of gravel and course sand, or gravel and dirt with sod. The latter will be utilized to conceal the French drain completely; while the other options will allow for easy access or maintenance.
As with most large projects, planning is critical to be sure everything runs smoothly. Some things you need to do before starting construction are:
Contact the local utility companies to have all underground lines located and marked.
Determine a location for leftover dirt. Most of the soil removed for the French drain trench will not be needed.
Start the trench at the end of the drainage system so adjustments can be made to the slope if an obstruction is encountered along the path.
Installing a French drain can be an excellent solution to drainage problems at your home. Royal Work Waterproofing Corp. is fully licensed and experienced in even the most complex issues. Call today for a free estimate, and let our experts fix your drainage issues permanently.