Storefronts & mixed-use buildings
Commercial flat roof repair in Philadelphia
Along Philly's commercial corridors, one flat roof often covers a shop or restaurant downstairs and apartments above. A leak there means a damaged ceiling, an unhappy tenant and sometimes a closed business. Call to reach a local roofer who works on small commercial roofs.
The buildings
What's on top of a Philly corridor building
Most small commercial buildings here are two- to four-story brick structures built tight to their neighbors: a storefront at street level and one or more apartments above. You'll find them along East Passyunk Avenue, Frankford Avenue from Fishtown up through Frankford, Girard Avenue, Main Street in Manayunk, Baltimore Avenue in West Philly and Castor Avenue in the Northeast.
Their roofs are wider and busier than a rowhome's. A typical one carries several HVAC units on curbs, a restaurant exhaust fan, plumbing vents for each apartment, a roof hatch, sometimes a skylight, and parapet walls with metal coping and old sign brackets. Many drain to scuppers through the parapet or to drains inside the building rather than to a simple rear gutter.
- Restaurant and café buildings with kitchen exhaust and grease on the roof.
- Retail with apartments above, where a leak reaches a tenant first.
- Corner buildings with taller parapets and decorative cornices.
- Converted warehouses and garages in Kensington and the River Wards with large, low-slope roofs.
When to call
Signs a commercial roof needs attention:
- Stained or sagging ceiling tiles in the store
- A tenant reporting drips or a damp ceiling upstairs
- Water around an HVAC unit or the exhaust fan
- Ponding around drains or along a parapet after rain
- Dark, soft or bubbled roofing near a kitchen exhaust
- Leaks that show up only in heavy downpours
Common problems
Why storefront and mixed-use roofs leak
HVAC curbs
Each rooftop unit sits on a curb that has to be flashed into the roof. Service techs walk around them, panels get dropped, and condensate lines drip in one spot for years.
Kitchen exhaust grease
Grease blown out of a restaurant exhaust fan collects on the roof around it. It breaks down some membranes and makes others slick and soft. A grease containment system around the fan protects the roof.
Internal drains & scuppers
Wide roofs often drain through a few drains or parapet scuppers. When leaves or debris block one, water backs up across the roof and finds the weakest seam.
Parapets & coping
Tall front parapets with metal coping, sign brackets and old cornice work let water into the wall from the top, and it often shows up on the storefront ceiling.
Tenant & service traffic
Tenants, contractors and service techs all use the roof. Foot traffic wears paths into the surface, especially between the hatch and the equipment.
Shared walls on the block
Corridor buildings butt into their neighbors, often at different heights. The flashing where a lower roof meets a taller building next door is a frequent leak point.
The work
What a commercial flat roof repair involves
Trace the leak
The roofer checks the affected ceilings inside, then the roof above them: drains, curbs, the exhaust fan, parapets and seams. Photos help when an owner, tenant or insurer needs them.
Clear & fix drainage
Drains and scuppers are cleared and strainers added, so water leaves the roof instead of backing up.
Repair the details
Curbs, vents and the exhaust fan get new flashing, and grease-damaged roofing is cut out and replaced. Coping and parapet tops are re-secured.
Plan what's next
If the roof is aging overall, the owner gets options: targeted repairs, a coating over a sound roof, or a full replacement.
Planning your job
What affects the price
Commercial roofs vary a lot, even on the same block. These drive the scope:
- Roof size and shape. Wider roofs, setbacks and multiple levels add area and edges.
- Equipment on the roof. Each HVAC unit, exhaust fan and vent needs its own flashing work.
- Drainage. Internal drains, scuppers and any re-pitching to stop ponding.
- Grease damage. Replacing softened roofing and adding grease containment.
- Access on a busy avenue. Hoisting materials from a sidewalk or alley, which may need city permits.
- Working around the business. Scheduling, tenant notice and protecting the interior.
- What's already up there. Old layers and the condition of the roof boards.
Start with the Roof Problem Checker to see how urgent a leak is.
Related pages
- South Philly flat roof repair: East Passyunk Avenue and nearby blocks
- Fishtown & River Wards flat roof repair: Frankford and Girard Avenues
- Northeast Philly flat roof repair: Frankford and Castor Avenues
- TPO roofing: a common choice for wider, busier roofs
- Flat roof coating: extending a sound commercial roof
- Storm damage roof repair: wind, debris and insurance
Owner tip: ask any contractor for a certificate of insurance before they go on the roof, and keep a record of every repair. It helps with tenants, insurers and anyone you sell the building to.
Commercial flat roof questions
Can the roof be repaired without closing my business?
Usually most of the work happens on the roof, so the business can often stay open. Noise, a hoist out front or work over the shop may need some planning. Ask the roofer how they'd schedule the job around your hours.
A tenant upstairs reported a leak. What should I do first?
Have the tenant move belongings away from the drip and photograph it, then get a roofer to trace the source. Upstairs leaks often come from a nearby drain, curb or wall joint rather than the spot directly above the stain.
Is grease from our kitchen exhaust really damaging the roof?
It can. Grease softens and breaks down some roofing materials over time and makes the area slippery for anyone servicing equipment. A grease containment unit around the fan, emptied regularly, protects the roof.
How often should a commercial flat roof be inspected?
Many owners have the roof checked twice a year, typically in spring and fall, and after major storms. Clearing drains and catching small flashing problems early is far easier than repairing interior damage.
Can an older commercial roof be coated instead of replaced?
If it's dry underneath and mostly sound, often yes. A moisture check comes first, because coating over wet insulation traps the water. See the flat roof coating page for who's a good candidate.
Have a different question about your building's roof? Call and ask a local roofer.
(215) 702-6130