How to Repair a Painted Fieldstone Foundation

Scrape off loose and crumbling paint from the foundation with a metal putty knife. If chunks of the fieldstone are loose or crumbly remove them as well. Sweep the floor with a broom after you scrape the foundation.

Clean the foundation either with a pressure washer or by hand. Do not use a pressure washer if your basement does not have adequate drains. If you clean the foundation by hand, fill a bucket with warm water and trisodium phosphate (TSP), an all purpose cleaner, and scrub the solution onto the foundation using a hard bristle brush, then rinse with water. If you decide to use a pressure washer, most local equipment rental stores will rent one for $40 to $60 a day. Fill a bucket with TSP and water and place the pressure washer detergent dispenser tune into the bucket. Spray on one section of the foundation at a time, then rinse with water.

Patch cracks and holes with a concrete patching compound. Concrete patching materials are available in caulk-like tubes and in regular container. Buy several of both. Use a caulk-gun to apply the patching compound to cracks and seams. Use a putty knife to fill in larger holes. Go over the area with a putty knife until it is smooth and even. Allow the patching compound to dry.

Attach the roller to an extension pole.

Pour two to three gallons of masonry primer into a five gallon bucket. Place a paint screen on an interior side of the bucket.

Dip the roller into the bucket and roll it on the screen to remove excess primer. Do one section at a time. Roll the primer onto the foundation. Go back over the same area with a brush and prime the areas that the roller could not reach. Repeat the process until the whole foundation is covered with primer. Allow the primer coat to thoroughly dry before applying the top coat.

Remove the old roller from the extension pole and place a new roller on the extension pole. Pour two to three gallons of exterior latex paint in a five gallon bucket.

Cut in the fieldstone foundation with the paint brush and follow up with the roller. Work on one section at a time. For the top coat, it is important to cut in first with the brush and then follow up with the roller. This helps to hide the brush marks by allowing the paint applied with the roller and the paint applied with the brush to blend together.