• The Fifth Fuel Homepage Image #1, VA
    Upgrade your home comfort and efficiency.
    Check out our expert insulation solutions!
  • The Fifth Fuel Homepage Image #2, VA
    With home performance, knowing is half the battle.
    Schedule a comprehensive energy audit today!
  • The Fifth Fuel Homepage Image #3, VA
    Cut energy costs and improve your home performance.
    Schedule our cost-effective air sealing service!

Welcome to The Fifth Fuel!

Heating and cooling accounts for nearly half of all home energy use, according to the US Energy Information Administration. There are many older and historic homes throughout Northern Virginia and Metro DC that lack adequate insulation, air sealing, and moisture protection.

The Fifth Fuel is a locally owned and operated company that has earned a strong reputation throughout DC, Falls Church, Alexandria, McLean, and beyond for providing effective energy efficiency solutions. We have over 30 years of experience in home performance and are highly skilled in getting to the root of home energy efficiency issues. The Fifth Fuel is certified by both BPI (Building Performance Institute) and RESNET (Residential Energy Services Network), ensuring a high level of expertise on each and every energy saving project.

Our team’s services are designed to make homes more energy efficient, comfortable, and durable. Energy efficiency upgrades benefit homeowners for decades and often pay for themselves in energy savings! Our energy conservation experts insulate attics, wall cavities, floors, and basements to make better use of your energy dollars. We encapsulate crawlspaces to save energy and promote indoor air quality, and air seal homes to prevent drafts and uneven indoor temperatures.

Do you want to get to the root of home energy efficiency issues? Call The Fifth Fuel today at to get started!

Your local home efficiency experts.

Get in touch with our team today!

703.368.1479

Schedule Service

Learn More

What is the Fifth Fuel?

See Our Latest Projects

What We Do

Upgrading home insulation is an effective solution for many energy efficiency issues.
Energy retrofits can significantly improve home performance, creating a lasting solution to comfort issues.

Air sealing is the most cost-effective way to increase home comfort and energy efficiency.

  • Energy savings for us

    I thought you might be interested to know that the night following the insulation work you and your crew did in our attic Tuesday, the temperature in most of the house (except the addition) only went down to 62F, even though the outside temperature was below freezing.

    J.R., Arlington, VA

    Services Provided:

    Attic Insulation
  • Professionalism & quality of work

    I wanted to take this opportunity to thank you for providing me with the name of Fifth Fuel as a contact for insulation work for my house.

    Bruce Cooper, Washington, DC

    Services Provided:

    Wall Insulation, Attic Insulation, Crawlspace Encapsulation, Spray Foam Insulation, Fiberglass Insulation, Insulation Removal
  • Couldn’t be more pleased

    I just want to take a minute to let you know the guys showed up on time yesterday, stayed late and did an awesome job! I couldn’t be more pleased with the outcome.

    Robert Withrow, Fairfax, VA

    Services Provided:

    Attic Insulation, Crawlspace Encapsulation, Wall Insulation, Insulation Removal, ENERGY STAR Partner
  • No more drafts

    I wanted to take a moment to follow-up with you on your work in our home this spring. As you predicted, it did not take as much work for our AC unit to cool the house and it seemed to hold the temperature better.

    K. Enloe, Leesburg, VA

    Services Provided:

    Spray Foam Insulation, Fiberglass Insulation, Attic Insulation, Wall Insulation, Insulation Removal
  • Timely service & quality of the work

    I would like to thank your staff for the timely service and quality of the work that was performed on my personal residence. The office staff has been very helpful with anything that was needed and the crew went above my expectations.

    Services Provided:

    Wall Insulation, Attic Insulation, Crawlspace Encapsulation, Blower Door Testing, Duct Blaster Test, ENERGY STAR Partner
  • Couldn’t be happier!

    I just received my March/April electric bill…and couldn’t be happier! I attribute your design and installation of the insulation package for much of the savings. I would recommend your team to anyone building a new home or renovating an existing home for superior quality and professionalism.

    Lance Lewes, Washington, DC

    Services Provided:

    Attic Insulation, Wall Insulation, Spray Foam Insulation, Fiberglass Insulation, Crawlspace Encapsulation
  • I’m really impressed

    Thank you for being so prompt. I can’t tell you how pleased I was to have someone with your knowledge and expertise in charge of my project. You delivered everything you promised and I’m really impressed. Thanks again for coming through. I will gladly recommend you and your company.

    Services Provided:

    Blower Door Testing, Duct Blaster Test
  • Your guys have been the best

    We would like to thank you for the work you have done for us. It was done efficiently and very professionally. As victims of Hurricane Sandy, we have had quite a few contractors to our house and thus far your guys have been the best.

    The McClarren Family, Alexandria, VA

    Services Provided:

    Spray Foam Insulation, Fiberglass Insulation, Wall Insulation, Attic Insulation, Crawlspace Encapsulation

The Latest from the Fifth Fuel Blog

Sick family laying in bed in Manssas VA, the Fifth Fuel can help!
We often go to great lengths to ensure that the health and safety of our families never ends up in jeopardy. It’s one of the reasons why we make sure that cleaning liquids and other toxic chemicals... Read more
Staircase in the modern home in Manassas, VA
For many Washington DC-area homeowners, dealing with temperature differentials between floors is a fact of life. Some let years go by simply assuming that they don’t have any control over this all-... Read more
dissection of house showing the inner parts
No matter what time of the year it is, you’ll be hard pressed to find a better solution to enhancing home comfort and energy efficiency than by focusing on insulation. It’s often assumed that... Read more