Low-Slope & Torch-Down Roofing in Franklin County, MO
A low-slope or torch-down roof in Union and Washington runs $4,500 to $14,000, set by square footage, the number of old layers, and how much decking failed underneath. Most Franklin County porch roofs, additions, and flat sections land between $6,000 and $10,000 in TriBuilt modified bitumen, installed in one to three days.
Any roof under a 2-in-12 pitch sheds water too slowly for shingles, so the porches, room additions, and flat sections on Union, Washington, and St. Clair homes need a sealed membrane instead. The National Roofing Contractors Association classifies these as low-slope roofs, and on those planes the seams are what fail first. Emmendorfer Exteriors installs TriBuilt torch-down modified bitumen on these sections, where the cap sheet is heat-fused into one continuous surface with no open joints for Missouri rain to find. Matt Emmendorfer started this company in 1990 and his sons Tom and Tim run the low-slope crews today, so the man who walks your porch roof is on payroll, not a number you call once.
Franklin County weather punishes flat planes harder than steep ones. Spring and summer storm cells push hail and straight-line wind across the southwest St. Louis exurbs, and water that ponds on a low-slope roof has time to work into a bad seam before it drains. Then winter freeze-thaw cycling lifts and cracks any membrane that was glued instead of fused. The older porch roofs on homes near downtown Union and in Washington's established neighborhoods are often the original rolled roofing, brittle and patched, sitting over decking that has quietly rotted. We tear those down to the wood so we can see what we are roofing over.
Tom and Tim grew up replacing failed decking instead of covering it, which is the part most low-slope jobs skip. A flat section over a Villa Ridge addition or a Pacific back porch usually hides soft sheathing and rotted fascia at the wall line, and a new membrane laid over wet wood fails again in a few seasons. When we strip the old roof we replace the bad decking and fascia before the first sheet of TriBuilt goes down, and if your section only needs a seam repair instead of a full replacement we will tell you that straight. Matt's rule from day one was to earn a repair today rather than sell a replacement you do not need.
What an Emmendorfer low-slope roof includes
No good-better-best games. This is what is in every low-slope and torch-down job we do across Franklin County.
- Tear off to the bare deck
- Replace failed decking and fascia
- TriBuilt torch-down modified bitumen
- Flashing and wall terminations done right
- Our own named crews and the permit
Tear off to the bare deck
No good-better-best games. This is what is in every Low-Slope and Torch-Down Roofing job we do across Union:
Replace failed decking and fascia
We strip the old rolled roofing or failed membrane down to the wood, never torch a new layer over the old one. A second layer traps moisture and hides rot, and on a low-slope plane that trapped water has nowhere to drain. Tear-off is the only way to see the decking before we commit to it.
TriBuilt torch-down modified bitumen
Once the section is open we replace any soft or rotted sheathing and the fascia board at the wall line, where low-slope roofs leak first. We price that wood honestly instead of roofing over it. Covering rotted decking is the single most common reason a flat porch roof fails again in three years.
Flashing and wall terminations done right
Our standard low-slope system is TriBuilt modified bitumen. The underside of the cap sheet is heated until it melts and fuses to the base layer and the previous course, so the finished roof is one continuous sealed surface. There are no glued seams to peel apart in Missouri freeze-thaw the way self-stick rolled roofing does.
Our own named crews and the permit
Where your flat section meets a wall, a chimney, or a higher roof is where the water tries hardest to get in. We run the membrane up the wall and install new metal flashing and counterflashing instead of reusing the old, then seal every termination by hand. This detail work is what separates a porch roof that lasts from one that streaks the ceiling.
How a low-slope job runs, start to finish
Five steps from the first call to the final walkthrough, so you know what happens and when.
We walk the section and measure it
Five steps from first call to final walkthrough. You know what happens and when, the whole way through.
A firm written price with the material named
Tom or Tim climbs up and inspects the actual low-slope plane, checks the seams and the wall terminations, probes the decking for soft spots, and measures every facet. You get an exact written number off a real inspection, not a satellite guess or a price over the phone.
We protect the property and tear off
Your estimate states the TriBuilt system by name and one straight number. The number you approve is the number you pay. If we find more rotted decking once the roof is open we show it to you before we replace it, so there is no surprise at the end.
We fuse the new system in place
We tarp the landscaping and siding below the work, set the dumpster on plywood to spare your driveway, and strip the old roof to bare deck. Then we inspect every sheet of sheathing and the fascia before any new material goes down.
Cleanup, magnet sweep, and walkthrough
We replace failed decking and fascia, install the base layer, then heat-fuse the TriBuilt cap sheet so the whole plane becomes one sealed surface. New flashing goes in at every wall, chimney, and roof-to-roof transition. Most low-slope sections finish in one to three days.
Why a family-owned, factory-certified roofer
Emmendorfer Exteriors is a family-owned roofing and siding company that Matt Emmendorfer started in 1990 in Overland, outside St. Louis, and moved to Union in 2003. It is run today by Matt and his sons Tom and Tim, with daughter Amy on media and Wendy running the office. The family has put roofs and siding on more than 2,400 Missouri homes since 1990. The standard is the same one Matt started with: walk the roof before quoting, name the manufacturer on the estimate, replace the decking and fascia that has failed instead of covering it, and tell the homeowner straight when a repair beats a replacement.
Low-slope roofing questions, answered
Get a written low-slope roofing estimate
A real Emmendorfer walks the actual section, names the TriBuilt system in writing, and gives you a number that does not change. Free and no obligation across Franklin County.