Flat and Low-Slope Roofing in St. Louis, MO

Each part goes on the way the manufacturer specifies, because that is the condition for a valid material warranty. Nailing and underlayment shortcuts void coverage, and years later the homeowner is left holding the problem.

A great deal of city housing is masonry with a shallow or effectively flat roof behind a parapet wall, and the parapet is where most of these roofs actually fail. Water gets in at the coping cap, through deteriorated mortar joints, or at the junction where the membrane turns up the back of the wall. The roof surface itself is frequently sound while the perimeter is not.

That makes the boundary between roofing and masonry the central question on a city flat roof, and it is where a lot of money gets wasted. Recoating a membrane under a failing parapet solves nothing, because the water was never coming through the field. We would rather tell you it is a tuckpointing and coping problem than sell you a roof that will not fix it.

Two-family and four-family flats add a wrinkle: the unit taking the water damage is frequently not the unit whose ceiling the water entered through, and with separate owners or tenants involved the diagnosis has to be clear enough to settle who is responsible before anyone commits to work.

Rear additions, sleeping porches and the low-slope sections over kitchens are the other habitual leak source. Many were built later than the main house, tied into existing brick with detailing that was marginal when new, and shingled at a pitch too shallow to shed properly.

Access changes the job in a way it does not in the county. Alley placement for a dumpster, narrow gangways between buildings, no driveway to stage material on, and in the historic districts a review process governing what is visible from the street. Those are scheduling and cost realities and they belong in the estimate rather than as a surprise later.