Industrial & Warehouse Roofing in Troy, MI

Many older plants and storage buildings have through-fastened metal panels on purlins, with no deck under them. Leaks start at fasteners whose rubber washers have hardened, at end laps where sealant has dried out, and at skylight panels and curbs cut into the ribs. The fixes, in rising order of cost: replace fasteners and reseal laps; coat the whole roof, which the code allows over metal panels without a tear-off; or build a retrofit, with new subframing, insulation and either new standing seam panels or a membrane over the old roof. Panel slope limits and system details are on the commercial metal roofing page.

Distribution buildings and newer plants typically run TPO, PVC or EPDM over rigid insulation screwed through to a fluted steel deck. On a roof of several acres, the cost driver is often what lies under the membrane. Wet insulation and rusted deck sections have to come out, and a tear-off brings the insulation up to the current energy code; see commercial roof insulation. A moisture survey before bidding tells you how many squares of deck and insulation to expect.

Cold storage turns roof physics around. In a heated building, moisture tries to move from the warm inside out. In a cooler or freezer, it moves from the warm outside in, so the roof membrane itself becomes the vapor retarder. A Professional Roofing article on these buildings found that air leakage, not vapor diffusion, causes the large majority of the moisture problems. Warm, damp outside air slips into the roof assembly and condenses on anything colder than its dew point, building frost and ice inside the insulation.

The fixes are in the details: air seals at every deck penetration (drains, refrigeration lines, vents), at boundaries between spaces held at different temperatures such as a dock beside a freezer, and redundant seals at the roof edge. The same article notes that ballasted systems are often limited by wind rules and that loose-laid insulation can open gaps as it shifts. A building being converted to cold storage needs a roof designed for it, not the roof it came with.

Manufacturing roofs carry make-up air units, process exhaust stacks, dust collector ductwork and pipe racks. Each brings curbs and supports that break the membrane, service traffic that wears paths across it, and sometimes discharge that attacks it. Ask for walkway pads on the service routes, equipment set on curbs or rails high enough to reflash under, and the membrane maker's written guidance on whatever comes out of the stacks. Kitchen grease is handled on restaurant roofing; process chemicals need the same check.

The model energy code requires skylights over large, high-ceiling manufacturing and nonrefrigerated warehouse space in new buildings, so many industrial roofs have dozens of them. Each one is a curb to flash and an opening to guard; see commercial skylights for curb heights and OSHA screen and cover rules.