Protecting your home against the elements

  • 40 years of experience
  • Licensed
  • Insured
  • A+ Rating with the BBB


ThermaGuard, Inc., a family owned and operated company, was formed in August, 1973 to capitalize on the growing market for home improvement in the Atlanta area.  Our focus is on exterior improvements of insulating and protective natures, such as roofing, vinyl siding, HARDIE Plank siding, gutters and gutter shields, decks and screened porches, and vinyl replacement windows.  Thus the name, ThermaGuard.

Our company is headquartered in Marietta, Georgia and serves Marietta, Woodstock, Roswell, Alpharetta, Dunwoody, Sandy Srpings, Kennesaw, Canton and surrounding areas.  We have installed thousands of roofs in our market area and were one of the first roofing companies to install architectural shingles here.  We also offer 3-tab shingles and modified style roofing for low pitched and flat roofs.

We are an Accredited Business with the Better Business Bureau sporting a coveted A+ rating.  We are licensed and insured.  ThermaGuard was selected to be seen on Home and Garden Television’s “Curb Appeal the Block” as part of Chip Wade’s specialist team.

It is our business philosophy to avoid aligning ourselves with a single roof shingle manufacturer. We feel it is important to offer the consumer our unbiased opinions.  This results in a trusting relationship with our customer, who appreciates our independence to help them make the right choices among all manufacturers rather than being associated with only one manufacturer, the way many of our competitors are. During their merger, GAF Elk asked ThermaGuard to serve on its Advisory counsel when the two companies merged.  We convey all manufacturers’ warranties to our customers and provide a writtenThermaGuard warranty for roofing.

Our vinyl siding and vinyl replacement windows are important insulating products when installed on your home, providing both energy and maintenance savings to you.  We also install the popular HARDIE Plank products and provide exterior painting for those installations.  Our seamless aluminum gutters are run out in your driveway for a custom fit to your roof.  These can be topped by the Leaf Off Gutter Protection System.  We also design decks in wood or composite materials, along with screened porches with all the trimmings to fit your home.

Our successful marketing strategy is to use only highly experienced personnel and thereby reduce waste in the estimating and installation process.  Keeping our overhead low, we pay our workers well, use top quality materials and keep our prices low. Result:  The best value for our customers.

Our founder, Allen Greiner, has an extensive background as a construction consultant specializing in innovative approaches to his clients’ projects.  Over 40 years of experience has led him to specify materials using the most rigorous standards for ThermaGuard projects.

Allen's wife, Marilyn, is the company's General Manager and has been with the ThermaGuard for over twenty years along with their sons, Michael and Chris. These key people are strategically placed within the company to assure that ThermaGuards's standards are met.  Many of our installers have worked with us for over 15 years.  This is a benefit to the consumer, because ThermaGuard values quality and intends to insure it into the next generation.  Thus, the ThermaGuard Warranty has real value that will be supported for years into the future.

ThermaGuard is happy to offer to the homeowner a free written estimate for any of its exterior remodeling services.

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Thermaguard Team

Gutters and Shields




"This is a testimony of appreciation and happiness for the awesome work of Thermaguard of Marietta, GA.

My 35 year old home was (overdue) for new siding and a correction of (bad installation) on the cathedral roof.  The team of Thermaguard was prompt, kind, efficient, and detail oriented until the job was complete.  I am 100% satisfied with the workmanship and do not hesitate to recommend this family business to anyone in need of siding or roofing. 

If you need to talk to me personally, please feel free to call Thermaguard’s main number for a follow-up with me."

Jane Gearhart