A roof leak in a commercial building can start small—but escalate fast. Whether it’s a warehouse, retail space, or office facility, even a minor water drip can lead to major problems like interior damage, mold, safety hazards, and disrupted operations.
So what should you do the moment you notice signs of a leak?
Step one: Don’t panic—but act fast. Step two: Call a commercial roofing contractor.
In this post, we’ll guide you through the basic process of what to check before making the call, and what you can expect after the pros arrive.
First Signs of Trouble: What You Might Notice
Leaks don’t always start with a downpour from the ceiling. Be alert to subtle signs, including:
- Water stains on ceiling tiles or walls
- A musty smell in rooms or hallways
- Damp insulation or warped drywall
- Puddles or dripping during or after rain
If you’re noticing any of the above, it’s a clear signal something is wrong up top.
Step 1: Walk the Space and Document What You See
You don’t need to go on the roof yourself. In fact, you shouldn’t. But take a few minutes to walk the affected area indoors and gather some basic info:
- Where is the leak showing up? Note the rooms or locations.
- How severe is it? Is water dripping steadily or just a stain?
- When does it occur? Only during rain? After storms?
- Take photos of the damage (wet ceiling tiles, water on the floor, etc.). This will be useful when the roofing contractor arrives—it helps them understand where to start their inspection.
Step 2: Call a Commercial Roofing Contractor Immediately
Time is your biggest enemy when dealing with water damage. The sooner you call a licensed commercial roofing specialist, the better.
Let them know:
- You’ve got an active leak or signs of one
- Where the symptoms are visible
- If the building is occupied or in use
- If there are any safety concerns (e.g., near electrical panels)
A reputable contractor will prioritize urgent cases like this and may offer same-day or next-day inspections.
Step 3: What Happens When the Roofing Contractor Arrives
Here’s what you can expect from a professional roofing contractor during the repair process:
1. Interior & Exterior Inspection
They’ll first inspect the inside of the building to understand where the leak is showing up. Then, they’ll move to the roof to find the actual entry point of the water—these two locations are often not the same.
They’ll check:
- Membrane or roofing surface for cracks, punctures, or ponding
- Flashings around vents, drains, skylights, HVAC units
- Drainage systems (clogged or broken drains are common leak causes)
- Roof age, wear, and previous repairs
2. Leak Diagnosis and Immediate Containment (if needed)
If water is actively entering the building, they may perform a temporary containment step to stop further damage—like sealing the area or diverting water flow.
3. Repair Proposal
Once the problem is identified, the contractor will present:
- A diagnosis of the issue
- A proposed repair solution
- Estimated costs and timelines
- Warranty information for the repair
If your roof is under warranty or part of a service plan, they’ll review how that factors in.
Step 4: The Repair Process
Depending on the severity and type of roof system, the repair might include:
- Replacing a section of membrane or damaged roofing material
- Resealing flashing or penetrations
- Clearing and correcting clogged drainage
- In some cases: restoring or recoating a larger section of roof
Most reputable contractors will document the entire process, and may provide photo reports before and after.
Step 5: Final Checks and Follow-Up
After repairs, the roofing team should perform a water test or weather observation to ensure the issue is resolved. You should also receive a formal summary of the work done, including any maintenance recommendations.
And if the contractor is thorough, they’ll schedule a follow-up inspection in the next season to make sure everything’s holding up well.
Bottom Line: Don’t Try to DIY a Commercial Roof Leak
Commercial roofs are complex systems—and most are under warranties or code regulations that can be voided by unauthorized repair attempts. That’s why the safest, fastest, and most cost-effective option is always to call a certified commercial roofing professional.
Leaks don’t wait, and neither should you.
