When is it Warm Enough to Start Roofing?

It’s that time of year again when roofing contractors like us are preparing to call our crews back to work. The long winter has drained our operating cash and the fact that spring is near makes us eager to get back at it. But every spring (and fall) the questions from our customers are the same.

• “When is it warm enough to install asphalt shingles”
• “Are the shingles going to seal down?”
• “Shouldn’t we wait until summer?”

The focus of this blog is on answering these questions. The information is based on our 50+ years of experience in the industry and research we’ve done online.

The fact is you can install shingles regardless of the temperature. Roofing in cold weather is not impossible and will not void the warranty.

That being said, we feel there are several drawbacks to roofing in cold weather and choose not to do it unless it is absolutely necessary. Following are some reasons why:

1. The shingles become brittle in cold weather. This increases the risk of them cracking when being formed into valleys or over ridges. It also becomes more likely that the nails may blow through the shingle if the air pressure of the nail guns isn’t set correctly or if the shingles aren’t nailed in the proper location. These problems can be mitigated by being aware of the risk, but it is a concern that problems could occur and go unnoticed.
2. Our equipment doesn’t work as well in cold weather.  The compressors don’t run as well and the moisture in the hoses causes the guns to freeze and stop working.
3. We become less efficient.  It is human nature to become less productive if you aren’t comfortable, plus the added clothing makes it harder to move.
4. It’s not worth the risk from a safety standpoint. Setting up ladders and crawling around on frosty or snowy roofs is dangerous for our employees.
5. The shingles won’t seal until spring. This isn’t a serious problem unless they blow off in the meantime or if too much dust and dirt collect on the seal strip.
6. The shingles may not lay as flat and may look rough or rippled. This problem will usually go away once the weather warms up and the shingles seal down.

So it’s still winter.  When is it warm enough?

We feel the risk of the problems listed above decreases significantly when the temperatures start to climb above 30 degrees consistently.  The shingles become more malleable and less brittle, our equipment functions properly and the snow and frost melt, making the job safer. The shingles still may not seal completely, but the risk of them blowing off before they do becomes less likely. Unless you are installing white or light-colored shingles, the roof temperature is usually significantly higher than the air temperature anyway. On a sunny day in the spring, the roof temperature may be 10 to 20 degrees warmer than the air.

So trust your contractor if they tell you it’s warm enough. If you have hired the right contractor, they aren’t going to be willing to compromise the quality of their installation and open themselves up to possible headaches down the road.