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Professional basement sealing tips for older homes.

Your guide to basement sealing with foam like a professional

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Basement sealing is a simple process that can save you money by enhancing your home’s energy efficiency. Our guide outlines how to use expanding foam to seal your basement like a pro.

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Basement sealing supplies

Basements are huge sources of heat loss in many older homes. Sealing your home’s basement can help you reap significant energy savings.

When it comes to sealing basements, Tyler Grace from TRG Home Concepts prefers to use modern and sustainable best practices. For exceptional results on all basement sealing jobs, the seasoned professional uses the following supplies:


Getting all of these materials and tools before you start the basement sealing work will ensure a smooth and efficient process. Also, make sure that you put on your safety gear before you start working.

How to seal a basement

How do you seal off a basement? To answer this question, Tyler adopts a simple but meticulous approach. Here’s a step-by-step breakdown of his perfected process:

1. Clear the work area. All surfaces that will come into direct contact with the basement wall sealer should be clear of any debris, dirt, or dust build-up. This will strengthen the bond between the sealant and the surface.

With that in mind, Tyler starts the process by clearing any dirt or dust accumulated along the rim joist area, the gaps around doors and windows, and any other openings that need to be sealed.

2. Cut rigid foam to size. Air leakages commonly occur around the rim joist area. Tyler uses pieces of rigid foam to insulate cavities along the rim joist. The insulation should be cut to size using a utility knife. Tyler says that using rigid foam helps prevent condensation and potential decay at the back of the rim joist area. This also safeguards against possible health issues further down the line.

When cutting the rigid foam, the seasoned expert leaves some space around it to apply expanding foam sealant.  

3. Install rigid foam in place. Installing the rigid foam is a delicate affair. Tyler applies some Loctite Power Grab Heavy Duty on one side of the rigid foam to hold it in place. Remember that the piece is smaller than the cavity, and he wants to leave room around the perimeter to accommodate the expanding foam. The adhesive eliminates any need for nails or screws and instantly holds the insulation to the rim joist firmly.  

Tyler Grace installs a piece of rigid foam in place.

4. Apply expanding foam. To create an air-tight seal around the rigid foam insulation, Tyler turns to Loctite Tite Foam Gaps & Cracks. He carefully applies the expanding foam around the rigid insulation. This basement foam sealant strongly adheres to various building materials, including metal, stone, brick, concrete, and wood, among others.

In addition to its adhesive properties, Tyler also likes this product because it remains slightly flexible after curing. The air seal created is guaranteed to hold even if something contracts, expands, or moves. The compact size of the can containing the foam makes it easier to reach into tight spaces around the rim joist.

Tyler Grace applies the expanding foam around the perimeter of the rigid foam insulation.

5. Install a second layer of rigid foam. For structures located in colder environments, Tyler prefers to use two layers of insulation. The second layer of rigid foam also helps with sealing the rim joist cavity past the adjoining wall studs.

Tyler installs the second piece of insulation the same way he did the first.

Tyler Grace installs the second layer of rigid foam insulation.

6. Cover the wall stud with expanding foam. To completely seal the rim joist area, Tyler applies Loctite Tite Foam Gaps & Cracks around the second piece of rigid foam. He also covers the adjoining wall stud with the expanding foam for a cohesive thermal break.

Tyler Grace applies the expanding foam over the wall stud.

7. Seal all gaps around windows and doors. A basement sealing job is not complete until all gaps and cracks around the windows and doors in the basement are properly sealed. To complete this part of the job, Tyler uses Loctite Tite Foam Window & Door. This product is specifically designed to be used to seal gaps and cracks around door jambs and window frames. It holds up well to direct exposure to UV rays, delivering long-lasting results.

Tyler Grace seals gaps around a basement window using Loctite Tite Foam Window & Door.

8. Seal electrical and plumbing openings. Any other unsealed openings, including those used for utilities like electricity and plumbing, also have a significant impact on your home’s energy efficiency. When basement sealing older homes, Tyler uses Loctite Tite Foam Big Gaps. This basement wall sealer can be used to seal off gaps and openings that are up to 3 inches wide.

Tyler Grace seals larger openings using Loctite Tite Foam Big Gaps.

The basement sealing process is complete! Old homes are charming and full of history. However, they also have glaring insulation issues. Properly sealing a basement helps eliminate unnecessary air leakages. This upgrade can make a house more comfortable and safer for its occupants.

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