• Winter front of house
    Take back control of your home this winter
    Retrofits can save money and improve comfort all year long.
  • Couple with black cat relaxing by woodstove
    Stay Warm and Cozy All Winter Long
    Find out how upgrading your home insulation can help
  • Air sealing a home using caulk
    Don’t sacrifice comfort this winter
    Cost-effective air sealing services can keep your family warm all winter long while reducing heating costs.
  • Block House wrapped in warm scarf
    Choose Lower energy costs without sacrificing comfort
    Our team is committed to making your home more energy efficient

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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 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 (703) 368-1479 to get started!

What is the Fifth Fuel?

Learn what's behind The Fifth Fuel name. We believe energy efficiency is the fifth fuel and is the greenest and most cost effective of all the energy options for your DC, MD, or VA home because the cheapest fuel is the one you don't have to buy.

See Our Latest Projects

With over 30 years of experience in home energy upgrades, we have helped many DC, Falls Church, and McLean homeowners save money on energy costs and improve home comfort. Check out our case studies.

What We Do

The Fifth Fuel retrofits existing home and commercial buildings in Falls Church, Arlington, Alexandria, and more, cutting energy bills, increasing indoor air quality, and boosting comfort through services like insulation, air sealing, crawlspace encapsulation, home energy audits, and more.

Air sealing is the most cost effective way to boost home comfort and indoor air quality while promoting long term home energy conservation and efficiency. Learn more about the air sealing services The Fifth Fuel offers homes and businesses in Metro Maryland, Northern Virginia, and more.

From spray foam insulation to cellulose and fiberglass, The Fifth Fuel team can boost the energy efficiency and durability of your Northern Virginia, Metro Maryland, or DC home with insulation services for attics, walls, crawlspaces, and more.

  • 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

bonus room, game room in finished attic
Learn why the converted room in your attic or over your garage has big temperature swings, and why properly insulating and air sealing these rooms can lower energy bills and make your whole home more... Read more
pink fiberglass batt wall insulation
Upgrade your home's insulation this spring and benefit all year-long from reduced heating and cooling bills and higher home comfort. The Fifth Fuel breaks down why the existing aging insulation in... Read more
ladder into attic space in home
Remove and replace your attic insulation today for improved home comfort and lower monthly heating and cooling costs. The Fifth Fuel breaks down the signs that your attic insulation needs to be... Read more