How to Repair a Precast Concrete Panel

What You'll Need
Step ladder
Old rags
Bucket of water
100- to 125-grit sandpaper
Caulking materials
Penetrating paints or stains
Putting knife or scraper
Working clothes
Working gloves

A precast concrete panel is created by casting concrete using a mold or frame. The concrete is then allowed to dry and cure under controlled environment conditions that are dependent on the intended use of concrete panel. Unlike concrete that is produced onsite, a precast concrete panel goes through quality controls, so many builders and homeowners prefer to use this type of material over the traditional concrete that is prepared onsite. Yet, despite the fact that precast concrete panels are considerably more stable and durable compared to site-cast produced concrete, precast concrete will still suffer damages and will need repairs. Fortunately, repairing minor damages and cracks on precast concrete panels are relatively easy.

Step 1 – Survey the Damage

You need to determine the extent of the damage on the precast concrete panel before you attempt to do repairs. Damaged paint coatings and small cracks that do no compromise the integrity of the concrete are easy to fix, but deep cracks can be quite challenging to repair.

Step 2 – Clean the Walls

After surveying the extent of the damage you can start cleaning the wall with a damp cloth. Do not put water directly on the surface of the precast concrete, especially if the concrete has deep cracks on it. After wiping the concrete with a damp cloth, allow the concrete to dry completely before you attempt to remove loose materials on the cracks. To get rid off loose materials from the cracks, use a dry paint brush with moderately hard bristles. You may also use fine grit sand paper to clean the area around the cracks. After sanding, use a damp piece of cloth to wipe away dust and debris. Make sure that you remove all loose materials from the cracks before you apply caulking materials.

Step 3 – Apply Caulking Materials

If you are using caulking materials in tubes, simply squeeze caulk into the cracks until the area is completely filled up. When applying caulk, start from the top of the wall and work your way down. Take care not to let the materials get in contact with your skin as you work. If you must use your hands to push the caulk into the cracks, wear working gloves. Otherwise, you should use a putty knife to push the caulk into the cracks and to remove the excess caulk.  Depending on existing weather conditions, the caulk should dry in about 30 minutes, so make sure that you work your way around the cracks methodically to avoid wasting time.

Step 4 – Apply Paint or Stain

After the caulk has completely dried out, sand away the rough areas and then apply paint or stain coating on the entire concrete panel. Be sure to apply the stain or paint in thin coats and let each coat dry before adding another one to prevent color mismatch.