Walter Aguilera Headshot


45714 Oakbrook Ct #180
Sterling, VA 20166
Mon-Fri 7:00am-5:00pm
In business since 2010

Comfenergy, located in Sterling, VA, is a locally-owned and operated energy services company, specializing in insulation, HVAC, and window replacement services to improve the overall comfort, health, and energy efficiency of residential or commercial buildings in Northern Virginia. The "Home Comfort Guys" specialize in fixing uncomfortable homes and businesses and they can help you too!

Hiring the authorized Dr. Energy Saver company in Alexandria and Northern VA means you can benefit from:

  • Energy Audits to Pinpoint Energy and Comfort Issues
  • Exclusive, Proprietary Insulation Products
  • Technicians Continuously Trained at Dr. Energy Saver's State-of-the-Art "Energy City"
  • Direct Contractor Financing Options for Qualified Borrowers
  • Free, No-Obligation Evaluations and Estimates - Contact Today!


  • Insulation added to attics, basements, crawl spaces, and walls to protect homes from cold, heat, and humidity; reduce noise, and provide even in-home temperatures.
  • Air Sealing to seal the gaps in your home that contribute to wasted energy and comfort issues.
  • Window Replacement to replace inefficient single-pane windows or drafty windows.
  • Ductwork Sealing and Insulation to fix leaks, holes, and loose connections in ductwork that can contribute to high energy bills, uneven temperatures, and poor air quality.

Products Installed:

  • Spray Foam Insulation
  • Blown-In Cellulose Insulation
  • Radiant Barrier Insulation
  • SuperAttic™ Rigid Foam Insulation System
  • ProWool™ Soundproofing Insulation
  • Energy-Efficient Replacement Windows & Doors

Service Area:

Comfenergy proudly serves Alexandria City County, Arlington County, Clarke County, Culpeper County, Fairfax County, Fairfax City County, Falls Church City County, Fauquier County, Frederick County, Fredericksburg County, Loudoun County, Manassas City County, Prince Edward County, Prince William County, Rappahannock County, Spotsylvania County, Stafford County, Warren County, Winchester County, as well as Jefferson County, WV. This includes the cities and towns of Sterling, Ashburn, Reston, Great Falls, Herndon, Vienna, Middleburg, Purcellville, Fredericksburg, and surrounding areas.

Check out insulation, window replacement, and HVAC before and after photos and read reviews and testimonials from customers below. Schedule your free evaluation and estimate today!

By Anna B.
"Amazing job and customer service! Mario is great!!"
By Laurie P.
By Tom And Shelly W.
"The most surprising fact that we learned was that the upstairs ceiling in the storage was ONLY..."
By Tom And Shelly
"Ruben and his crew were extremely polite & very helpful."
Michael H.
Ashburn, VA
The crew was clean and professional.
Matt S.
Brambleton, VA
The sales person answered all my questions and were very patient with me.
S. E.
Aldie, VA
Mario is a true professional.
Comfenergy Before & After
  • Frozen Pipes in Ashburn, VA
    Frozen Pipes in Ashburn, VA

    Frozen Pipes in Ashburn, VA

     The homeowner in Ashburn called,  as last year their pipes froze and they did not want that to happy again.This home i has always had issues with hot and cold spots, and freezing pipes in the winter.  We found cold air in the master bedroom attic to be getting around the batt insulation leading to the bathroom above.  This entire neighborhood of as notorious drafts and hot/cold spots. These homes have also dealt with many frozen water lines. The water lines were freezing almost 20 feet from the exterior of the home! Comfenergy installed 4" thick SilverGlo foam boards with heat reflective barrier on the attic walls.   Problem solved!!!  Foam board insulation in an attic keeps the cold air from travelling beneath the bathroom tub and the pipes from freezing. The homeowner will be more comfortable in the Summer and Winter.....but it lessened the draftiness of the home, and the pipes don't freeze any more!!!  
  • Increasing


    This home was having comfort issues on their top floors in the summer. Our solution was to increase the R-value by installing cellulose insulation and air sealing their attic.
  • Spray Foam Garage Ceiling-Ashburn, VA
    Spray Foam Garage Ceiling-Ashburn, VA

    Spray Foam Garage Ceiling-Ashburn, VA

    This Ashburn, VA had rooms over the garage that were too hot in the summer.  This is can often be caused by fiberglass batts installed by the builder in the ceiling of the garage.  They fall away from the sub-flooring depleting all thermal insulating value.  This customer decided to remove the entire garage ceiling and use closed cell spray foam to fix the problem.
  • Utility Room air sealing-Sterling, VA
    Utility Room air sealing-Sterling, VA

    Utility Room air sealing-Sterling, VA

    This Sterling, VA homeowner had a utility room that backed up to their garage.  There was a lot of air leakage allowing cold air to travel through the utility room and into the basement making it cold in the winter.  Thermax foam boards and one part foam was used to seal this air leakage off, and to keep it safe from flammability.  Thermax is a fire resistant material.
2020 #1 Dealer in the Network

2020 #1 Dealer in the Network

Inc. 5000 List

Inc. 5000 List

Loudoun County Chamber Small Business of the Year Award

Loudoun County Chamber Small Business of the Year Award

Carl Depner

Certified Comfort & Energy Consultant

Matt Pascual

Certified Comfort & Energy Consultant

Pedro Guillen

Certified Comfort & Energy Consultant

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