How to Paint the Foundation of a House in 6 Steps

Before you pull out your paint and give your foundation the TLC it craves, you need to clean it. Your concrete foundation is a porous surface, so it’s easy for dirt, debris, and grime to get stuck in it, making it difficult for paint to adhere to the surface. Trisodium phosphate (TSP) will be your best friend here. TSP is a heavy-duty cleaning agent that effortlessly wipes away grime from the dirtiest surfaces. Wear protective goggles, gloves, long sleeves, and full-length pants if you plan to use TSP because it can irritate the skin with direct contact.

Spray your foundation down with your hose or pressure washer to remove any loose debris. Then, mix 1/4 cup of TSP with 2 gallons of hot water. Apply the solution with a sponge and allow it to sit on the surface for around 30 minutes. You can then use a wire brush to scrub away any stubborn grime. After you’ve scrubbed your foundation, use the hose or pressure washer again to spray it down, removing the cleaning solution and remaining dirt.

Before moving on to the next step, give your surface at least 24 hours to completely dry.

After you’ve allowed your foundation to fully dry, patch up any areas with minor imperfections. Mix up a concrete and masonry patching compound and use a trowel to apply it to any cracks you see. You’ll need to wait at least four hours for the compound to dry, but it could also take up to six hours to dry. 

It's worth noting that this step will only work for minor repairs. If you think your foundation has large-scale structural damage, you’ll need to contact a foundation repair company near you to assess the situation and develop a permanent solution.

Do you have a rock garden that’s beautiful in its natural state and wouldn’t benefit at all from a splash of paint? Or maybe that lush green garden you’ve been growing is finally starting to show the fruits of your labor, and the last thing you want to do is feed it paint and primer. 

When there’s an area in your landscape or around your home that you want to protect from flying paint and primer, use a drop cloth and painter’s tape to keep it safe. You know the saying “less is more?” That doesn’t apply here. Secure drop cloths to any location that has even the smallest chance of coming into contact with your paint, primer, and sealant. The prep work in this stage will be a lot easier than trying to scrape up sealant from somewhere it doesn’t belong.

A concrete sealant and primer will help your paint job last longer than if you just painted without either. A sealant will work as a barrier between your foundation and the elements. Primer will give your paint a favorable surface to stick to when applied, making your final look smooth and clean.

First, apply two layers of sealant using a concrete paintbrush and roller or sprayer. A sprayer will have an easier time getting your sealant into all the tiny cracks and pores in the concrete, but a roller will also get the job done. 

Allow your sealant to dry for the amount of time specified on your product by the manufacturer. If all else fails, wait at least two hours between coats. Afterward, apply the primer, starting at the corners first and working inward. Once you’ve finished priming your foundation, wait eight hours for it to dry completely before painting.

Use the same method and tools you used when priming to apply the paint. Start with a thin layer of paint for your first coat, making sure to get the paint between any crevices and dips on your foundation’s surface. 

Then, wait at least 12 hours for the first coat to dry and sand down any noticeable painting drips or inconsistencies. Use a brush to gently sweep any sanding particles off your foundation. After this, you can apply a second coat.

Once you’ve finished painting, give it a few hours to dry and remove all the drop cloths and painter’s tape. Wait a few days and then take another look at your paint job to see if there are any areas you need to touch up or if you’ll need to apply a third coat.