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Let’s make your home airtight!

Say goodbye to drafts: how to fix small gaps in walls

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Eliminating drafts in your home can significantly reduce energy costs and create a more comfortable indoor environment. Our guide explains how to make your home airtight using foam insulation.

Why do you need to make your home airtight?

Air leakage is one of the top causes of energy loss in homes. Unsealed gaps and cracks around windows and doors or openings in walls can lead to moisture problems, drafts, and higher cooling and heating costs. One of the best ways to resolve air leaks is to use insulating foam sealant to seal all of these openings.

This guide takes you through fixing small gaps in walls and around windows and doors using insulating foam. 

Causes of small gaps in walls and around trim

Small gaps and cracks in walls and around windows and doors can be caused by:

  • Use of fiberglass insulation: It is common for builders to fill gaps left around windows, doors, and rim joists with fiberglass. Regardless of how tightly the fiberglass is packed in place, air can still pass through. Since fiberglass is a poor air barrier, using it alone can lead to uncomfortable drafts in the home and the associated energy loss.
  • Foundation issues: A shifting or unevenly settled foundation can lead to gaps around windows and doors. Other signs of a shifting foundation include sticking windows and doors, uneven floors, and cracks in the walls.
  • Improper installation: Doors or windows that are improperly installed will have noticeable gaps around them.
  • Seasonal expansion and contraction of building materials: Periodic weather changes can cause wood to expand and contract, leading to gaps in floors, walls, or trim.

Use foam insulation to address drafts and moisture issues caused by gaps associated with the above causes.  

How small gaps lead to energy loss

Tiny gaps and cracks in floors, ceilings, and walls allow cool air to escape in the summer and let heat out in the winter. This significantly reduces your home’s energy efficiency. Over time, your energy bills rise as your HVAC system works harder to maintain a comfortable indoor environment. These gaps can also lead to moisture problems, growth of mold and mildew, and severe structural damage.

Boost your home’s energy efficiency by sealing these gaps using an effective insulating foam product.

Common air leakage points

Some of the common but easy-to-miss air leakage points around your home include:

  • Around windows and doors: Gaps around door and window frames are known for letting in drafts. The right foam sealant can fill these gaps, prevent moisture and air leaks, and boost insulation and energy efficiency.
  • Rooflines and attics: Foam insulation can be used to seal hard-to-reach areas, along rooflines, eaves, and attics. This will enhance your home’s overall insulation and reduce energy consumption.
  • Where two materials meet: Any area where two materials meet, like rim joists, can be a significant source of air leakage and heat loss. Seal these areas with insulation foam to prevent drafts.
  • Wall penetrations: Places where vents, cables, and pipes penetrate the wall are commonly left unsealed. Use a foam sealant to completely fill these openings, regardless of whether they are irregularly shaped.
  • Gaps and cracks in exterior walls: Have you seen any gaps or cracks around your home’s roofline, siding, or foundation? Use insulating foam to prevent air leaks and enhance energy efficiency.
  • Crawlspaces and basements: Cracks and openings along foundations or adjacent walls can lead to moisture issues in basements and crawlspaces. Properly seal these spaces using expanding foam to prevent moisture accumulation and mold growth.

How to fix small gaps in walls using foam insulation

An assortment of Loctite foam insulation products.

Here is a step-by-step process of how to seal air leaks.

1. Get the right supplies: For smooth progress, gather all the necessary supplies before starting this project. The essentials include:

2. Identify gaps and cracks: Inspect every inch of your house, looking for gaps, cracks, or openings that need to be sealed. Use the above list of problem areas as a guide to simplify your work.  

3. Prepare the surface: Ensure the area is clean and dry before applying the foam. Clean the surface to get rid of any dirt, grime, and debris.

4. Ready the insulation foam can for use: Shake the can according to the directions provided. With the can upside down, squeeze the nozzle until you have a consistent flow of foam.

5. Apply foam: Start applying the foam over all gaps and cracks around your home. Remember to leave space for the expansion of the foam. 

A handyman applying insulating foam over a gap.

6. Cleaning up: Wipe away uncured foam on walls and other surfaces using acetone or foam cleaner. Avoid using water to clean off wet foam on the skin; just use a dry rag to wipe it off immediately.

A handyman trimming away excess insulating foam after curing.

7. Curing and trimming: Trim any excess after the foam is completely cured. You can also paint over it to ensure it matches the surrounding area. 

Choosing the right foam sealant to fix small gaps in walls

To achieve the desired outcome, you must use the right insulating foam products for each specific application. Loctite offers a selection of foam products designed for different applications. If you want to seal gaps and cracks up to one inch in size, choose Loctite TITE FOAM Gaps & Cracks. For bigger openings up to three inches in size, go for Loctite TITE FOAM Big Gaps.

Use Loctite TITE FOAM Window & Door to seal all gaps around door and window frames effectively. To keep tiny pests and critters out of your home, seal gaps in walls using Loctite TITE FOAM Pest Block. Lastly, reach for Loctite Fire Block Foam where it’s required by code. In addition to improving energy efficiency, it enhances safety in the event of a fire. The foam's bright orange color makes it easily visible to inspectors conducting a frame inspection.

All Loctite TITE FOAM products are designed to adhere firmly to various building materials, including PVC, metal, stone, brick, concrete, and wood. The resulting seal can withstand direct exposure to harsh UV rays while retaining its flexibility for an extended period.

Products used

  • Loctite Fire Block Pro Foam 12oz Can
    Loctite Fire Block Foam

    Specialty insulating foam formula designed to be fire resistant and easily identifiable to resist the spread of fire and hot gasses.

  • loctite tite foam big gaps 12oz can
    Loctite Tite Foam Big Gaps

    Seal and insulate gaps & cracks up to 3” inside or out

  • loctite tite foam gaps cracks 12oz can
    Loctite Tite Foam Gaps & Cracks

    Seal and insulate gaps & cracks up to 1” inside or out

  • 8596377380-Loctite-Pest-Block-foam-eCom-cards-FOP
    Loctite Tite Foam Pest Block

    Loctite TITE FOAM Pest Block is a new polyurethane-based insulating foam sealant endorsed by Combat.

  • loctite tite foam window door 12oz can
    Loctite Tite Foam Window & Door

    Specialized formula will not bow windows or doors

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