There are an estimated 30,000 roofing contractors across the United States, all proudly serving their respective cities. Each has its geography and climate to account for. So what makes Denver roofing projects special and unique? Actually, it’s several things.
Denver Roofing Landscape
The Denver metro area has hundreds (some estimates say thousands) of roofing contractors. Because of the unique climate in the Denver area, there are more roofing companies here than in many other large cities. This provides customers with plenty of high-quality roofing contractors to choose from. Most of the residential roofs in Denver are built with asphalt shingles, while commercial buildings are typically either single-ply membrane or gravel built-up roofs.
Unique Factors of Denver Roofing Projects
The climate and geography of the Denver metro area make roofing projects here different than most other major cities. We have listed some of the special considerations Denver roofing companies must account for below:
The Denver metro area has four distinct seasons. While many other cities are known for a specific climate, in Denver we must contend with extreme cold and extreme heat, along with wild weather in the “shoulder” seasons (Spring and Fall).
How heat affects Denver roofing construction
Many of our clients are not aware that the sun’s beating UV rays are a roof’s second biggest enemy (behind water). The UV rays warp, wrinkle, and shrink many roofing materials. The heat also means Denver roofing projects have to include allowance for ventilation and insulation. Without a ventilated roof or attic, your interior can overheat and lead to high air conditioner usage. And in the winter, unventilated attics can result in ice dams and leaks. Insulation is equally important, as it protects your interior space from the heat outside.
How cold affects Denver roofing construction
The cold winters in metro Denver cause roofing projects to have special considerations as well. Insulation still matters as it regulates interior temperature distinctly from the cold winter outside. But snow loads also must be factored into Denver roofing projects. On steep roofs, snow will drain naturally off the roof. But depending on your roofing material, you may need snow retention installed on your roof to prevent injury or property damage from skidding ice and snow. On flat roofs, your roof deck must be built to hold the additional weight that winter snow brings, which may be 40 lbs per square foot (or more).
Storms and Weather
Noting that “weather” is different than “climate”, Denver roofing projects also must account for the extreme weather patterns that can occur here. Denver not only experiences a true four-season climate but within each season there are extreme weather events that affect your property’s exterior. Some examples are:
- Hail – Denver roofing construction should factor in the widespread hail we receive. In fact, Colorado had the 2nd highest hail-damage insurance claim activity as recently as 2019. Impact-resistant roofing materials are now widely available and can protect your property from damaging hail. On average, 85% of the roofs we install are impact-resistant.
- Wind – It is common for the Denver area to receive multiple wind events in excess of 70 miles per hour each year. Wind of that degree puts extreme pressure on your roof. When it comes to wind affecting Denver roofing projects, we recommend a wind rating of 110 mph or more (such as Owens Corning Duration 130 MPH wind rating) on steep roofs. On commercial roofing projects, we suggest fully-adhered single-ply systems, which provide the most strength against high winds.
- Snow – every few years, the Denver metro area receives a massive snowstorm that brings the city to a halt. These storms create immense weight, particularly on commercial roofs. For this reason, most modern commercial properties are built with very strong 22 gauge steel roof decks to be able to accommodate the worst of Denver’s snowstorms.
Another unique quality that must be factored into Denver roofing projects is the geography of the Denver metro area. Denver is unique, as it’s the only large metropolis within a 600-mile radius (the only large US city where this is true). The result of our geographic location is we are on a supply-chain island. This can affect how Denver roofing projects are planned for and executed, as building material availability plays an important role.
Many roofing material manufacturers have wisely launched factories or distribution centers in Denver to be able to handle roofing projects here and in the neighboring cities and states. This allows Denver roofing companies to furnish materials for our projects without needing to wait weeks or months for materials.
Denver Roofing Requirements – Commercial Roof Projects
When it comes to the special items to pay attention to on commercial Denver roofing projects, there are quite a few. It’s common for Denver-area commercial buildings to have flat roof structures, which require expertise from Denver commercial roofing companies. Some of the items to pay special attention to are:
- Built-in insulation – many Denver commercial roofs are designed with insulation as part of the roof system. Because the Denver area experiences both extreme heat and cold, the local building code requires R30 insulation in the roof. The most common way to achieve this is with five inches of rigid polyiso insulation foam boards to be installed on top of the roof deck. Five inches can be a lot of space when it comes to roofing construction and may require creativity on the part of the commercial roofing contractor.
- Snow load and drainage – Because of the frequent heavy snow in the wintertime, roof decks must be able to handle heavy weight. And when snowmelt drains, there needs to be a sufficient slope in the commercial roof to ensure it drains away from the property.
- Material choice – Most modern Denver roofing projects on commercial properties are built with single-ply membranes. The primary membrane installed in 2022 is TPO, which is a white thermos-plastic material. The white material is highly reflective, helping to keep buildings cooler in the hot summer.
Denver Roofing Requirements – Residential Roof Projects
There is also special attention needed for Denver roofing projects on residential structures. Those items are:
- Impact resistance – because of the frequent hail we receive, Denver roofing companies must be knowledgeable in impact-resistant roofing materials. Impact resistance is typically defined by Underwriter’s Laboratories (UL) as either Class III or Class IV. Materials that are rated Class III or Class IV by UL include certain asphalt shingles, synthetic shingles, concrete tiles, and synthetic slate/shake products.
- Snow retention – on certain roof materials, such as metal and slate, it’s critical to ensure that snow remains on the roof and melts naturally into gutters. Without snow retention clips or fences on the roof, injury or damage can occur after the ice slides off.
- Ventilation – on steep roofs with attic space separate from the home’s interior, ventilation is crucial. In the summer heat, proper ventilation will reduce the finished interior space’s temperature and the corresponding air conditioning/electricity usage. In the winter cold, ventilation regulates temperature to reduce ice damming and unwanted condensation.
Denver roofing projects are not for the faint of heart. With the dispersed geography, weather, extreme storms, etc that are present in the Denver area, roofing contractors must maintain a high level of knowledge and skill. Whereas in some cities that are known for a specific type of weather, Denver roofing contractors have to deal with four distinct seasons and know how to build roof strength for each.