Generally speaking, you shouldn't install a new roof in the rain.
Never, ever climb on your roof during lightning storms.
After rain, let the roof dry for two days before continuing work.
Seal roof underlayment or vulnerable sections off with a tarp before rain.
It's not unusual to feel concerned if you're replacing your roof and the forecast calls for rain. New roof installations cost about $5,000 at minimum, so it’s reasonable you’d be worried about your investment—or rain seeping into the top portion of your house.
If rain's in the forecast—or precipitation catches you off guard while you're up there working—it's best to halt roof work for a bit and let the weather pass. Learn why below, plus steps you can take to weatherproof your roof's vulnerable portions and achieve peace of mind when rain descends on a roofing project.
Can You Install a New Roof When It's Raining?
The short answer is no—you shouldn't install a new roof when it's raining. This goes for even the savviest DIY homeowners who tackle their own roof installation projects, as well as anyone who opts to hire a roofing professional to complete the work.
Installing a new roof in the rain is dangerous for whoever's working. It's also not healthy for the wood sitting underneath the roof, which can become damaged after prolonged water exposure. In the best-case scenario, you (or your contractor) should know when rain is about to strike and seal off any gaps or cracks, and tarp off any vulnerable areas.
What to Do if You See Lightning During a Roofing Job
If you hear thunder or see lightning, you or your roofing contractors should immediately—but carefully—get down from the roof. Never climb on your roof or even step on a metal ladder in lightning, even if it means something gets wet that isn't supposed to. A couple of extra days of dry time is far more favorable than risking a personal injury.
Can Roofers Install a New Roof in the Rain?
Most roofing professionals won't risk installing a new roof in the rain—which further proves that you shouldn't be on your roof during inclement weather, either. That said, some contractors may opt to work in light rain or fluctuating showers if they are up against a deadline and feel it's safe to continue.
Roofers have experience working in all conditions, so as a homeowner, it's probably best to let them determine when it's safe to work. Don't worry too much about your roof becoming damaged in the rain, either. Most pros will seal off holes and gaps as they work to prevent water from seeping through.
What Happens If It Rains While Putting on a Roof?
If a roof is under construction and showers enter the forecast, work will stop for a day or two. This can be disheartening, but it's the best decision for all parties involved. This way, everyone stays safe, and your roof is installed properly.
Inclement weather is one reason you should always choose a roofing contractor that's licensed and insured. If, in such a scenario, someone got injured while working on your roof in the rain, you wouldn't be liable.
What Happens if It Rains While Replacing a Roof?
Tearing off an old roof to update it or replace the entire thing is a similar process when it comes to bad weather—roofers will tarp off vulnerable sections until the showers pass.
If you're simply doing DIY roof maintenance, you should check the weather forecast each day before getting to work. When inclement weather is expected, you can get ahead of it and plan a week's worth of work around rain in the forecast.
How Long Does It Take a Roof to Dry After Rain?
Two days of drying time is the guideline many roofing professionals stick to. If heavy rain strikes, or if your new roof hasn't dried, an additional third day may be warranted to allow things to fully dry out.
Be patient with your contractor if this happens—it's truly for the best. New roofs should never be installed on wet materials. Wet sheathing underneath your roof can warp wood or lead to moisture getting trapped, compromising the strength of your roof and potentially cause mold as well.
How to Protect Shingle Installation During Bad Weather
If rain showers hit during shingle installation, you or your contractor should cover any exposed underlayment with a tarp. You can use a staple gun to seal it down if you expect high winds that could blow the tarp off.
Basically, play it safe and do the best you can. Unless the forecast calls for the heavens to open up for multiple days, the worst-case scenario is that you may have to let things dry for a few days before you continue on your roofing journey.