How to Install French Drains

Now that the foundation experts have left your new construction or addition project you have a giant muddy trench around the actual foundation walls. That will need to be backfilled unless of course you would like to film your very own war movie in the back yard!! But don't start now!! You will first need to call a local sand and gravel yard to purchase some drainage stone. This stone usually is sold by the cubic yard and is delivered to your job sight in massive dump trucks. If you are feeling rather adventurous and have a rather large truck then they will allow you to pick it up yourselves. Either way you will need a lot of this stone to get the job done. I started with a few truckloads for my 15'x30'x15' addition and ordered more if I ran out which I did. If you get too much of this stone, don't panic. It makes great walkway stone and you will need more anyhow for the interior of the foundation, just under what will become the basement's cement floor. For my drainage stone I called Campton Sand And Gravel of Campton NH.

Now that your drainage stone is ordered and on its way you will want to stop in at Home Depot for a few other little odds and ends. If you or your foundation guy haven't already done so purchase yourself some foundation tar. This tar is similar to what you would use to seal your driveway. You paint it onto your foundation prior to backfilling to produce a watertight seal. You will want to pick up a few rough bristle driveway brooms for the application process. Purchase the tar like you purchase paint. Look at the coverage on the can and then look at your wall square footage. Also pick up enough sheets of thin foam board insulation to cover your foundation up 4' from the bottom. These come in 4'x8' sections so that should help you to calculate what you need. This will go up against the tar when it is sticky and help to insulate your finished basement.