What Temperature is Too Cold for Roofing? The Truth Revealed
It’s the middle of winter, but you have a roofing emergency. You may be wondering how cold is too cold for roofing your house.
The temperature that is too cold for roofing is 30 degrees Fahrenheit. Most roofing companies will tell you they don’t install roofs below 40 degrees. This is because asphalt shingles tend to crack below that temperature.
But the truth is that as long as you take preventative measures, roofs can be installed in temperatures above 30 degrees.
Why Excessively Cold Temperatures Are Not Suited For Roofing
When the temperature drops below freezing, then it is too cold for roofing. Although many roofing companies won’t work when the temperature is under forty degrees Fahrenheit because it may void the warranty on the roofing material, and the working conditions can be brutal.
The most common roofing material is asphalt shingles (source). And when the temperatures drop below forty degrees Fahrenheit, these shingles:
Will get brittle.
They can crack if not installed correctly.
Their adhesive strips won’t adhere well
There are other types of roofing materials also very sensitive to temperature and require some extra care when installing, such as
EPDM rubber membrane
But there are roofing materials not sensitive to the temperature when being installed, such as
Wood Shingles and Shakes
They are easy to lay down, and no extra installation steps are needed during cold weather. However, there are other issues. Extreme winter weather conditions make it dangerous for roofers if they don’t take the proper precautions. These precautions include
Working slowly and carefully
Wearing proper nonslip winter boots
Remove snow and ice from the work surface
Making sure to vent the attic properly
Being aware of skylights and other hidden hazards
Making sure the roof structure is sturdy
Roofing companies are accustomed to installing roofs during the winter months, especially in the colder climates where the temperatures frequently drop to below freezing.
As long as the temperatures stay above 30 degrees Fahrenheit, they should have no problems. Plan on it taking much longer than normal for the installation process because of the special care you have to take for cold weather.
Roofing companies can charge extra for the work because it takes longer and is more dangerous. The upside is there is a low demand for roofing, so no wait times for the customer (source).
Most experienced roofers are comfortable working in very cold temperatures and shouldn’t have a problem adapting to the winter weather.
Another bonus to installing roofs in the winter is the weather. Many times, when preparing to reroof a structure, the old roofing material will have to be removed. This exposes the bare layer to the elements. Snow is easy to remove, but rain soaks the bare layer and can take forever to dry out.
Extra Steps Needed for Roofing in Very Cold Temperatures
Besides the physical precautions of clearing away work surfaces and wearing the right clothing, there are some extra steps roofing companies need to take in order to properly and safely install roofs in very cold temperatures.
Installing Asphalt Shingles in Cold Temperatures
Asphalt Shingles are the most common material used for roofing. The manufacturers recommend that they be installed between 70 and 80 degrees Fahrenheit (source).
And to not install them when the temperature is below forty degrees without following the manufacturer’s recommended installation process.
These steps include
Keep all shingles and other related materials, including the adhesives, in a warm building where the temperature is no cooler than fifty degrees for at least 24 hours before installing them.
Make sure you store the shingles on a flat surface because it will bend or deform if not laid flat.
Bundle them together to increase surface warmth.
Plan out the installation so you know what area is getting installed and what materials are needed.
Use adhesives that are specifically made for cold weather. As they have more liquidity, it may affect the application process.
Make sure the surface area is free of ice and other debris
Only bring out the material you’ll need right before you start working so that it stays flexible.
Place the material next to the roof area you’ll be working in.
Follow manufacturer’s instructions for installing products for cold weather.
Never throw or drop the material, as it could be brittle and break.
Some types of asphalt shingles have a self-sticking adhesive strip that helps it stick to the roofing material and each other and is activated by a few weeks of exposure to heat.
When it’s below forty degrees, use dabs of asphalt roofing cement to help hold the shingles down.
Pay attention to the ridges and valleys, which could lose shingles to wind and weather if not properly secured.
Use winter weather membranes to seal eaves and skylights, or any area that needs to be sealed.
Take special precautions when nailing shingles down by using a straight angled flush, as you could break them with too much force
Make sure your nail gun and compressor are set at the right pressure and depth to adjust for the cold temperatures. As well as the air hose, which can constrict in cold weather.
Consider nailing by hand if your nail gun seizes up or you aren’t able to get the right angles.
If you are reroofing over the existing roof, make sure it lays flat and smooth. Otherwise your new roof will mimic the old look. Be careful when walking across shingles that aren’t flat as they could break or cause the adhesive to fail.
Installing Other Types of Shingles in Cold Weather
Although asphalt shingles are the most common roofing material, you can use other types of shingles instead that require adhesives.
Clay tiles are an option for when needing to reroof your house, as long as they are Grade 1 and rated for cold weather. These types of tiles can handle the freeze-thaw cycles prevalent in colder climates.
EPDM Rubber Membranes are normally used for flat roofs and can be installed in cold weather.
When installing any shingles that require adhesives, make sure to keep your materials in a warm place and follow the manufacturer’s instructions for cold weather installation.
You can also use other materials that don’t require adhesives such as
Wood Shingles and Shakes
These types of materials use nails to secure them or other types of fasteners. Because they don’t need adhesives to hold them in place, they are much easier to install in the winter.
In fact, some companies prefer installing metal roofs in the winter because of the cooler temperature. Metal heats up very quickly in the summer and makes it uncomfortable to work with.
Make sure the roof surface is dry and free of debris
Be aware of any skylight or other areas that might be covered by snow.
Temperatures Too Cold for Roofing
When the thermostat drops to below freezing or close to zero, then trying to install a new roof is practically impossible.
Remember: Even though the lowest recommended temperature for installing asphalt shingles is only forty degrees, you can continue to work in tempertures above 30 degrees as long as you follow these steps and take precautions.