As exterior remodeling experts, we install high quality, long-lasting roofs. Grennan Construction is the leading residential roofing contractor in Oakland County, Michigan, serving the community for over 20 years. We are home to a team of dedicated, professional, roofing installers, that strive for excellence and providing our customers with the best service possible.
After roof replacement
Before roof replacement
After roof replacement
After new roofing, siding, and gutters
Before new roofing, siding and gutters
After new gutters
After new addition, roofing, James Hardie siding, windows, and gutters
Before new addition, roofing, James Hardie siding, windows, and gutters
After new gutters
When a roof can account for as much as 40% of the average home’s exterior, many factors weigh into the choice of materials. Some surfaces are more beautiful than others. Some offer greater resilience or endurance. Some are more affordable. But the one roofing surface which offers all those attributes in balance is the asphalt shingle.
Now accounting for about 80% of the residential roof surfacing in the United States, asphalt shingles are measured against a variety of standards that evaluate fire and wind resistance, tear strength, and other key performance indicators.
Asphalt shingles have a glass fiber reinforcing mat manufactured to the shape of the shingle. This mat is then coated with asphalt which contains mineral fillers. The glass fiber mat is not waterproof by itself. Its purpose is for reinforcement. What makes the glass fiber shingle waterproof is the asphalt. However, the asphalt itself will not stick to the mat. For this reason, “fillers” are used. The fillers in the asphalt cling to the glass fibers in the mat. The asphalt then encapsulates the glass fibers, fills all of the little holes and voids in the mat rendering it waterproof. After this cools a bit, adhesive asphalt is used to cover the mat and the ceramic granules are then embedded.
Grennan Construction, Oakland Counties leading residential roofing contractor, is proud to install shingles from only the highest-quality manufacturers – such as CertainTeed, GAF and Owens Corning. When your roof is on the line – only the best will do.
The ceramic granules are there for two reasons. The primary reason is to protect the shingles from the sun. The sun’s UV rays are very damaging to asphalt and cause it to deteriorate prematurely. This is one of the reasons that gravel is used on built-up roofs. The second and more obvious reason for the granules is aesthetics. Asphalt shingles are available in a wide variety of colors to match almost any facade or landscape.
Most people think replacing their roof is simply replacing shingles. However, we want our customers to know better!
Today, effective roofing relies on advanced material technology and an integrated systems approach to protect your biggest asset – your home.
Proper attic ventilation is crucial to a long-lasting roof system. Poor attic ventilation can ruin your insulation, destroy your shingles, and raise your energy bills!
It is estimated that 9 out of 10 homes in North America do not have proper attic ventilation. Why? Because most people are unaware that attic ventilation can impact the longevity of their entire home! In the summer, an improperly ventilated attic can cause heat to build in excess of 160°F. This superheated air eventually penetrates the ceiling insulation into the living area below.
A properly ventilated attic can help reduce the load on your air conditioner by moving the superheated air out of your attic before it builds up and causes damage. In the winter, various household appliances, bathtubs, showers, and cooking vapors can contribute to excess moisture build-up. Improperly ventilated attics will allow this moisture to collect and cling to the underside of the roof. There, it will condense and fall, soaking the attic insulation and reducing its efficiency.
Attics should be properly ventilated to help prevent ice dams in cold northern climates. During the winter, ice and snow on a roof will melt and run down the deck to the cooler eaves. This run-off can re-freeze, creating an ice dam that will trap moisture on the roof. The moisture can eventually back up under the shingles and enter your home – causing hundreds or thousands of dollars of damage to your ceilings and walls. Adequate attic ventilation will reduce the amount of initial melting that occurs on your roof, thereby reducing the chance that ice dams will form.
Proper Attic VentilationProper attic ventilation systems allow a continuous flow of outside air through the attic, protecting the efficiency of the insulation and helping to lower temperatures in the living space. It consists of a balance between air intake (at your eaves or soffits) and air exhaust (at or near your roof ridge).
The FHA (Federal Housing Administration) recommends a minimum of at least 1 square foot of attic ventilation (both intake and exhaust) for every 300 square feet of attic space. For example, if your attic is 900 square feet, you need a total of 3 square feet of ventilation. This amount is generally divided equally between intake and exhaust ventilation (i.e., 1 1/2 feet of each), to insure proper air flow through the attic.
Protect your home from fire and damage with a quality membrane system. A quality membrane roofing system will provide long-lasting protection for the low-slope areas of your home (e.g., porches, garages, car ports, sun rooms, etc.) without the danger or hassles associated with conventional roofing products.
Let the sun shine in with a quality skylight! Skylights are the perfect way to add natural light to family rooms, kitchens, bathrooms, or any room that would benefit from the architectural style and luxury of a skylight.
Can You Install a New Roof in the Winter?
Read our blog about installing your new roofing system in the winter months.
"Did a great job helping devise solutions for problems with a 98-year-old historic home. Carpentry & paint skills excellent! Good communicators. Always knew what to expect."
"I had a masonry job on my late 1920s home and Grennan Construction did an absolutely outstanding job. I would definitely use them again in the future!"
"I've used Grennan Construction for repairs and upgrades to my home and business. Fred and his crew have always done a great job at a reasonable price."
Join over 3.5K Oakland County residents by signing up for our informative, monthly newsletter.
Since 1988 we have been serving our community by providing the best residential roofing and siding services in Oakland County. Today, sign up to receive monthly updates, home maintenance advice, and special deals available only through our email newsletter.
We proudly serve Auburn Hills, Berkley, Birmingham, Bloomfield Hills, Clawson, Clarkston, Commerce, Davisburg, Farmington Hills, Ferndale, Franklin, Hazel Park, Highland, Holly, Huntington Woods, Lakeville, Leonard, Keego Harbor, Lake Angelus, Metro Detroit, Milford, Madison Heights, New Hudson, Novi, Oak Park, Oakland, Oakland County, Orchard Lake Village, Pleasant Ridge, Pontiac, Rochester, Rochester Hills, Southeast Michigan, Sylvan Lake, South Lyon, Southfield, Union Lake, Walled Lake, Troy, Villages of Franklin, Lake Orion, Ortonville, Oxford, Waterford, White Lake, West Bloomfield, & Wixom.