If your detached garage is having problems with dampness when it rains, then you need to waterproof its exterior foundation. Exterior waterproofing prevents water from collecting around the foundation's bricks and wicking its way up into the wood timbers used to frame the garage's walls. It will also prevent problems with dampness, mold, and termite infestations.
Foundation waterproofing is a project you can do yourself or you can elect to have a professional contractor do the work. If you want to save money and tackle the project yourself, then follow these steps.
Step 1: Remove All Landscaping Around the Garage's Perimeter
Since you need to dig a trench around the garage's entire perimeter, you need to remove any landscaping that's present. If you want to replant bushes or other plants when you are finished, then dig around them far enough to keep their root balls intact. Wrap the roots in damp burlap fabric for protection.
Step 2: Dig a Trench Around the Garage
The next step is the most labor-intensive. You need to dig a trench all the way around the garage. The trench needs to unearth all of the foundation's bricks. Once you hit the concrete footer they are sitting on, then you need to dig out the top of the footer and a few inches down just next to it. It's important you dig out next to the footer, but don't dig the dirt out from underneath it. This can undermine and crack the foundation!
Step 3: Clean and Dry the Foundation Wall and Footer
To apply a waterproof sealant on the foundation, first, it needs to be cleaned of all dirt. Wash the wall well using your garden hose or a pressure washer set on low.
Once the wall has been washed, then either let it dry overnight or dry it with a leaf blower.
Step 4: Apply Fiber Coating and Liquid Rubber
Once dry, apply foundation fiber coating to the area where the foundation bricks and footer come together. Once it has dried and cured, then paint the entire footer and foundation wall with liquid rubber foundation waterproofing sealant.
Step 5: Place Gravel in the Trench
Once the rubber coating has dried, fill the trench with 1" gravel up to the top of the footer.
Step 6: Place Corrugated, Perforated PVC Pipe Into the Trench
On top of the gravel, install corrugated, perforated PVC pipe with the perforation holes pointing down towards the gravel. The holes must be pointed downward to allow excess water to flow away from the foundation and to drain down into the gravel below.
Step 7: Finish Up the Job
Finally, now you can finish up the foundation waterproofing project for your detached garage by covering the rest of the pipe and trench with gravel, putting the soil layer back over the gravel, and replanting any landscaping you previously removed.
For more information, contact an exterior waterproofing professional.