Skip to content

Contractor’s Corner

Roofing, painting, siding and window tips and tricks from Rocky Mountain Roofing & Exteriors
How to Find a Roof Leak

How to Find a Roof Leak

Finding a soft spot or discoloration in your ceiling is a chilling experience. It usually indicates a roof leak. In these times, you have two options–call your friendly Denver roofing company or, if you’re feeling adventurous and handy, you can try finding the source of the leak yourself. If it’s small enough, you may even be able to perform your own minor roofing repairs.

As we always say on this blog, a roof is a bad DIY job in general because it’s extra dangerous and difficult. So even if you track down the source of your leak, chances are you’ll still end up wanting to bring in the roofing task force. Finding its source, however, can save your roofers some time , which in turn can save you some money.

Below, we’ll get into how to find a roof leak so you can see if you want to try it yourself or go straight to the phone for help.

How to Find a Roof Leak

As the old zen koan goes, he who finds a roof leak in the ceiling finds not its source. Beautiful, isn’t it?

It’s because the water from the roof leak has probably been traveling since it got through the roof and has only recently arrived at the place where you see your ceiling-bound evidence. The actual leak could be across the house.

There are two methods for how to find a roof leak. One starts on the outside of the roof; the other starts on the underside of the roof,  in the crawlspace or attic. By the end of the roofing repair experience, both will essentially have been done; the question is just about where to start.

Briefly, starting on the outside and working in can be very hard. Unless you have crooked shingles or some other good visual marker for where the problem might be out there, you’ll have to look under every shingle until you find rusty nails. The nails are rusty because they’ve been exposed to leak water. Then you can start removing shingles and seeing how widespread the damage is.

For today, let’s start in the crawlspace. Take a wide-beamed flashlight up with you and examine the underside of your roof closely. You’re looking for mold and/or spots that are discolored because they are or were recently soaked. If you find mold, you may be able to follow it visually to its source, which is probably the source of the leak.

If there’s no mold (lucky!) and the weather’s been nice lately and dried up all the moisture in your roof, you’ll have to make it rain. While you’re in the crawlspace, have a roofing repair buddy stand outside with the garden hose and soak each section of the roof, one by one.

IMPORTANT: Never power wash your roof. Make sure the hose either has no attachment or is set to a gentle flow. If you hit it with the “jet” setting, it’ll blow your shingles right off and start a new, custom-made leak.

It’s not a bad idea to take a Bluetooth headset and your cell phone up into the crawlspace with you so you can communicate with your hose operator. Walkie-talkies are also great, mostly for their aesthetic.

Eventually, you should start to see some hose water come through the roof. And there you go. He who finds the leak has found the leak.

Key Considerations when Finding a Leak

The roof leak may be able to be patched. Some insulation will probably have to be replaced. How to replace insulation is its own subject; for now, we’ll leave it at this: please wear the proper safety equipment so you don’t, for example, breathe the stuff and insulate your insides.

Also, if you have to walk around up there under the roof, make sure to only step on the joists. It’s like finding a stud when you hang something heavy on a wall; if you step on anything that’s not a joist, you might put a foot through your ceiling, which will ruin your day, and that part of your ceiling.

Finally, if you’re at it for an hour or two and you just can’t find anything, it’s okay. This is a hard job–so hard that it takes research to even try it, no? Don’t spend too much time on or in your roof. It’s always dangerous. If you don’t meet with success after a little while, just give us a call at (303) 377-2801.

Roofing Repair Professionals

Roofing repair pros have the equipment and training needed to do this job safely, effectively, and quickly, at least as quickly as it can be done safely. We come equipped with big lights that can light up a whole attic, moisture sensors, and much more.

In truth, a roofing repair job is a relatively small job for a roofing company and it’s not worth the risk and hassle of trying very hard to do it yourself. And while we’re up there, we can give the whole place a once-over and give you an overall roof health report.

Recap of How to Find a Roof Leak 

Outside-in or inside-out. If you start on the outside, it’s like turning over infinite stones to try to find the underside of a stone that looks a little bit wrong. If you start on the inside, it’s more like spotting mold or soaked areas. Easier.

Insulation may be damaged and need replacing.

Follow the mold.

If you can’t find anything, have someone soak the roof with water in sections so that you can see the leak in action.

Call some roofers. If you don’t do any of this besides calling the roofers, that’s okay. Your purpose in doing so is to see if the problem is minor enough that you feel like trying to fix it or to save the roofers you call some time. For a free estimate on roof repair with Rocky Mountain Roofing & Exteriors, click here!