Re-establish positive drainage and correct ponding areas
Rebuild flashings at parapets, curbs, and penetrations, where most older BUR roofs actually start leaking Replace or top off gravel surfacing where it has scoured or washed thin
Built-up asphalt roofing on Houston commercial and industrial buildings: multi-ply BUR, gravel and reflective surfacing, repairs and recovers for heat, hail, and heavy rain.
- Built-up roofing, and why so many Houston buildings already have it
- Built-up roofing, BUR, is the original flat-roof system: alternating layers of asphalt and reinforcing felt or fabric, mopped together into a thick, monolithic membrane and finished with a protective surface. It is the roof you find on a large share of Houston's older commercial and industrial stock, the warehouses, distribution buildings, and mid-century low-rise properties that make up so much of this market. If you own one of those buildings, there is a good chance you own a built-up roof, and a good chance the conversation is about how to keep it alive or how to surface it for the Gulf Coast climate.
- The system's strength is exactly that it is built up in plies. Three, four, or more layers of asphalt and felt mean the waterproofing is genuinely several membranes thick, so a single blister, split, or puncture rarely turns into a leak straight through to the deck. For a low-slope industrial roof that takes foot traffic and rooftop equipment, that redundancy is the reason BUR has lasted as a category for over a century.
- How a built-up roof is assembled
- The plies
- Over the deck and insulation, we lay a base sheet, then build the membrane by alternating bitumen with plies of reinforcing felt or fiberglass mat. Each layer is bonded into the asphalt below it. The number of plies determines the membrane's thickness and durability, and that count is one of the things we specify to match how hard the building works the roof.
- The surfacing
- The top of a BUR roof has to be protected from the sun, and that surfacing is where the system meets the Houston climate head-on. The traditional finish is a flood coat of asphalt with gravel or slag embedded in it, which shields the asphalt from UV and adds mass against wind. The other path is a reflective finish, a smooth cap and a light-colored coating, which we discuss in detail below because in this city it changes how the roof performs.
- The surfacing decision is a Houston decision
Roof planning guidance
A bare or dark-surfaced asphalt roof in Houston absorbs an enormous amount of heat. Summer rooftop temperatures soar, the asphalt softens and ages faster, and the cooling load on the building climbs all season. Because heat and UV are the dominant stress on any roof here, the surfacing you choose on a built-up roof is not cosmetic, it is the difference between a roof that bakes and one that reflects. Gravel or slag surfacing protects the asphalt from UV and gives the roof ballast and a measure of impact resistance against spring hail A reflective coating over a smooth-surfaced BUR drops the membrane's surface temperature, eases the air-conditioning load, and slows UV aging of the asphalt below
Schedule a roof review
On a warehouse near the Port of Houston or a low-rise in Westchase where the owner is watching summer utility bills, we frequently recommend restoring or recoating an aging built-up roof with a reflective surface rather than living with a dark, heat-soaked membrane. It can extend the roof's life and cut cooling cost at the same time.
How BUR handles the weather this coast throws at it
The multi-ply construction is well matched to Gulf Coast conditions. Wind uplift during hurricane season has to overcome a heavy, fully bonded membrane rather than a single sheet, and gravel surfacing adds mass that resists scour, though loose gravel itself needs to be managed so it does not become a projectile in a real storm. The redundancy of the plies also gives the roof resilience against the hail that rolls through in spring, since damage to the surface and top ply does not necessarily reach the deck.
Water volume is the part that demands attention. Houston's sudden, heavy downpours dump a lot of rain on a large flat roof in a short time, and that water has to reach the drains, scuppers, and ultimately the Harris County drainage system before it sits. Ponding is the enemy of any low-slope asphalt roof, standing water accelerates aging and finds the weak laps, so we treat drainage and slope as part of the roof, not an afterthought. After Harvey in 2017, a lot of owners learned how much standing water their roofs could see, and ponding correction has been a steady part of the work ever since.
Repair and restoration before replacement
Most of our built-up work is not tear-off, it is keeping a sound roof in service. A BUR membrane that is aging gracefully is often a strong candidate for restoration rather than replacement, which is good news for an owner spreading a budget across several Houston buildings.
Roof planning notes