When a commercial roof starts leaking, the first 60 minutes determine how much damage spreads inside the building. A fast, organized response protects tenants, equipment, and inventory while keeping repair costs from climbing. Here is exactly what to do, minute by minute, from the moment you spot it.
Safety comes first. Water near electrical outlets, light fixtures, or ceiling tiles that are starting to sag creates a real hazard, so keep people clear of that area before anything else. If it is safe to do so, shut off power to affected circuits.
Place buckets, trash cans, or tarps under the active drip to catch water and protect flooring underneath. Move anything electronic or valuable out of the drip path. Before any cleanup starts, take photos and a short video of the leak, the water spread, and any damaged materials. This record matters later, both for your own building files and for whoever repairs the roof.
Once the immediate area is secured, widen your check. Walk nearby rooms and look up, since water travels sideways along joists and ductwork before it shows up somewhere obvious. Notify tenants or staff in the affected area, set out wet floor signage, and move inventory or equipment away from anywhere water could reach next.
A commercial roof leak needs someone trained on the specific system involved, whether that's TPO, EPDM, PVC, modified bitumen, or metal. A general contractor patch from the inside can mask the problem without stopping it, and it often makes the actual repair more expensive later.
If your leak is happening right now, reach out to Sierra Group's roofing team and we'll walk you through the next steps over the phone while we get someone moving toward your building. Our team handles emergency response across all the major commercial roofing systems, so whatever is on your roof, we've likely worked on it before.
Photograph the active leak, the water spread, and any damaged materials or equipment. Note the time you detected the leak and every action you took in response. This record helps your maintenance team plan next steps and gives whoever repairs the roof a clear picture of what happened before they arrive.
The clock on water damage starts the moment the leak happens, not once a repair is scheduled.
According to the EPA's guidance on mold and moisture, it is important to dry water damaged areas and items within 24 to 48 hours to prevent mold growth. That window is shorter than most property managers assume, and it starts counting down during the exact hour a leak is spotted.
Most emergency leaks trace back to something that could have been caught earlier. Worn seams, clogged drains, and ponding water are the usual suspects on low slope commercial roofs. A routine maintenance program catches these issues on a schedule instead of waiting for them to show up as a ceiling stain. If your building hasn't had a maintenance visit this year, ask our team about a custom plan built around your roof
.
Northeast Arkansas puts commercial roofs through real stress each year, from heavy spring rain to high summer heat to sudden temperature swings. That combination wears down membranes, seams, and drainage systems faster than a lot of property managers expect, which is part of why leaks often show up right after a stretch of severe weather.
Not sure if your roof needs a repair or a full replacement? Read our guide on Commercial Roof Replacement: When Is It Time?
Sierra Group Roofing & Solar is GAF Master Elite certified and has a HAAG Certified Commercial Roof Inspector on staff, and we've served property managers and building owners across Northeast
Arkansas since 2017. Whether you need someone on the roof within the hour or you're ready to set up a maintenance plan so this doesn't happen again, contact our commercial team and we'll take it from there.
What should I do first if I notice a leak on my commercial roof?
Clear people away from the area, especially near electrical fixtures, and place a container or tarp to catch the water. Take photos before you start any cleanup.
Can I patch a commercial roof leak myself?
Temporary containment like buckets or tarps is fine. Actual repairs should go to a roofer who works on commercial systems, since patching the wrong spot or using the wrong material can make the leak worse.
How fast does water damage spread inside a commercial building?
Water travels along joists, ductwork, and wall cavities, often showing up in a different room than where the leak started. Damage can spread within hours, and mold risk begins within 24 to 48 hours if materials stay wet.
What roofing systems are most prone to sudden leaks?
Low slope membrane systems like TPO, EPDM, and modified bitumen are common on commercial buildings and are especially vulnerable at seams, flashing points, and areas where water ponds.
How do I know if I need emergency repair or if it can wait?
Active water intrusion, especially near electrical systems or sensitive equipment, needs an immediate response. A slow drip in an unused storage area still needs attention soon, but may not require an emergency call.
Who should I call for a commercial roof leak?
Call a roofing contractor experienced with commercial systems rather than a general handyman or contractor. They'll know how to trace the leak to its source instead of just treating the symptom.