25% of home energy loss is attributed to air leakage
Air leakage occurs when outside air enters, and conditioned air leaves the home through cracks and openings. It is not synonymous with proper ventilation.
During the colder seasons, too much air may enter the home, causing drafts. Inversely, warm air from inside home can leak out. In the warmer seasons, cooler, conditioned air can leak out.
Besides wasting energy air leakage causes a number of different problems.
Air leakage also contributes to moisture problems. Moisture can compromise a structure’s stability. It can also eventually lead to mold, which can negatively affect your family’s health.
*To learn more about Air Leakage, visit this page from the U.S. Department of Enegy.
What is an air leakage test?
An air leakage test, often called a blower door test, measures how much air leaks into or out of a building by using a powerful fan mounted in an exterior door to depressurize the house and detect leaks. It’s usually performed by a certified energy auditor, home performance contractor, or HVAC professional trained in building science.
Below is a diagram of a Total Duct Leakage Test provided by Energy.Gov.
Consider professional air sealing
While you can absolutely take on air sealing as a do-it-yourself project, there will be some areas in your home that you might have a more difficult time finding or even reaching. Professionals like Cameron Home Insulation have the proper tools and knowledge to get the job done most effectively.
Cameron Group Home Insulation can ensure ensures that all leaks—even hidden or hard-to-reach ones—are properly found and sealed using the right materials and techniques. We take all the research out of the process, knowing which products are most effective for which areas. Our expertise allow us to improve energy efficiency, indoor comfort, and air quality more effectively than DIY efforts, often leading to bigger energy savings and longer-lasting results.
Don’t worry—because we value honesty and integrity, when we evaluate your space, we will let you know if/how you can DIY a project if it’s an easy fix.
Got a general question about home insulation? Don't know where to start? We've got answers.
Where to air seal in your home
Whether or not you hire a professional, reducing the amount of air that leaks in and out of your home is an easy, affordable way to reduce heating and cooling costs, improve your home’s durability, increase comfort all year round, and create a healthier indoor environment.
There are many crevices that require air sealing. Additionally, each area requires different techniques and materials.

Source: Energy.Gov.
Staircase Framing at Exterior Wall
Use spray foam or rigid foam board with caulk to seal the framing joints and gaps.
Windows and Doors
Use weatherstripping and caulk to seal gaps around frames and sashes.
Fireplace Wall
Seal gaps around the fireplace insert and at framing joints with fire-rated caulk or insulation.
Wall- and Window-Mounted AC Units
Weatherstrip around the unit and install insulating panels if needed.
Foundations and Floors
Use rigid foam insulation and caulk or spray foam to seal where walls meet foundations and around rim joist.
Attic Kneewalls and Attic Access
Insulate and weatherstrip access doors and seal gaps along kneewalls with rigid foam and caulk.
Air Ducts
Seal all duct joints and seams with mastic or foil tape and insulate ducts in unconditioned spaces.
Dropped Ceiling/Soffits
Seal gaps around soffits with spray foam or caulk from the attic side.
Electrical Outlets
Add foam gaskets behind outlet covers and use caulk or spray foam around the electrical box edges.
Garage Walls
Insulate and caulk all gaps where garage walls connect to the living space.
Common Walls Between Attached Units
Seal all gaps and joints in framing and drywall with caulk or spray foam to block air movement.
Recessed Lighting
Use airtight IC-rated recessed lights or install an insulated box over existing fixtures and seal with spray foam.
Porch Roof
Air seal where the porch roof meets the main house wall with caulk or spray foam.
Switch Plates
Install foam gaskets behind the cover plates to block air leaks.
Exterior Wall Penetrations
Seal around pipes, vents, and wires entering walls with caulk or spray foam.
Living Space Walls
Seal around baseboards, electrical boxes, and other penetrations with caulk or spray foam.
Chimney Shaft
Install a metal flashing and seal it with high-temperature fire-rated caulk or spray foam.
Whole House Fan
Cover and seal the fan with an insulated box or cover when not in use.
YOU CAN DO SOME AIR SEALING YOURSELF
There are a number of ways you can air seal your home. The first step is always to detect air leaks. (Tip: Check for suspicious spots on your ceiling paint and carpets. They may be caused by air leaks in interior wall/ceiling joints and wall/floor joists.)
It is never a bad time to make sure your home is properly air sealed. The U.S. Department of Energy provides a lot of information about air sealing on their website. Additionally, you can buy materials for weatherstripping at your local hardware stores
Even if you’ve done some air sealing yourself, it’s always good to get an expert opinion to check that you’ve done it properly.
Call 443-290-5182 to speak to an expert.
PROFESSIONAL WORK CAN PAY FOR ITSELF
Air sealing is an important home improvement project. Every home can benefit from it in the long run. However, it can also be labor intensive and confusing.
Finding out which materials to use and how to use them properly takes a lot of time to research. Afterwards, the actual installation takes more time without a team of professionals. When you account for the time spent, physical labor, and cost of materials, you may find that hiring professionals can be more cost-effective.
When the job is done properly with the best materials, the return on our investment can be significantly higher.
Cameron Home Insulation air seals homes in DC, MD, and VA.
If you live in Washington, DC, Maryland, or Virginia, Cameron Home Insulation should be your first choice when it comes to selecting the best insulation service for your home. We are an independently owned and operated, fully licensed, bonded and insured contractor that has been in the full-service home insulation business for four generations. We are expertly trained in the proper installation and safe removal of all types of insulation.
Call 443-290-5182 for more information on how you can benefit from a FREE Home Energy Assessment.
Alexandria, VA
Anne Arundel County
Arlington, VA
Baltimore City, MD
Baltimore County
Calvert County
Carrol County
Fairfax County
Frederick County
Harford County
Howard County
Montgomery County
Prince George's County
Queen Anne's County
Talbot County
Washington, DC
Cameron Home Insulation's main mission is to help local families experience more comfort and energy savings in their homes. For four generations, we've proudly served the Washington, DC, Maryland, and Virginia tri-state area. Our expertise in insulation and building science allows us to tailor the right solutions that bring the most value to our customers.