The short answer
Which commercial roof system is best for an Oklahoma building?
For most low-slope commercial buildings in Oklahoma, TPO is the default: it is reflective, heat-welded at the seams and handles the temperature swings. EPDM is the proven alternative, modified bitumen suits small or heavily detailed roofs, and a reflective coating is the cheapest option when the existing roof is still dry and sound.
Answers
What is the difference between TPO, EPDM and modified bitumen?
TPO is a white single-ply membrane welded with hot air at the seams. EPDM is black rubber glued or taped at the seams. Modified bitumen is a rolled asphalt sheet torched or adhered down. All three work; they fail differently and suit different roofs.
TPO handles heat and reflectivity best. EPDM has the longest track record and tolerates cold. Modified bitumen suits small roofs with many penetrations where a torch-down detail is easier than a welded one.
How long does a TPO roof last in Oklahoma?
A properly installed TPO membrane typically gives 15 to 25 years here with documented maintenance. Ponding water and blocked drains cut that short far more often than sunlight does.
Oklahoma's summer heat is hard on any membrane, but the failure we see most is water standing on the roof because a drain is blocked or the slope is wrong. Maintenance is what buys the years.
Is a white roof really cheaper to cool in Tulsa?
Yes, a reflective white membrane lowers the roof surface temperature and reduces the cooling load in an Oklahoma summer. The saving shows up on the utility bill in July and August and is largest on a building with a lot of air conditioning.
The benefit depends on insulation and duct location. On a well insulated building the reflectivity still helps, but insulation is where the bigger saving lives.
When should a commercial roof be coated instead of replaced?
Coat when the existing membrane is sound, the insulation underneath is dry, and the problems are surface level. Replace when a moisture survey finds saturated insulation or the deck is failing. Coating over a wet roof traps the water in.
A coating is the cheapest per square foot option and it is genuinely the right answer more often than contractors admit. The test is a core sample and a moisture reading, not an opinion.
What is a moisture survey and why does it matter?
A moisture survey uses infrared imaging or a capacitance meter to find wet insulation under the membrane, confirmed with core samples. It is what separates a repair from a replacement on a commercial roof.
Without it, a contractor is guessing. With it, the scope is a map: these areas are wet, these are dry. That map is also what justifies the cost to an owner or an insurer.
How much does a commercial roof recover cost versus a tear-off?
A recover installs a new membrane over the existing one where code and the deck allow it, and costs less than a full tear-off because there is no removal or disposal. A tear-off is required when there are already too many layers, the insulation is wet, or the deck needs repair.
Recover is a real saving, not a shortcut, but only when the deck is sound and the moisture survey is clean. Recovering over wet insulation seals the problem in.
Do commercial roofs need a maintenance contract?
Yes if you want the warranty to hold and the roof to last. Most manufacturer warranties require documented maintenance, typically twice a year, covering drains, seams, penetrations and flashing.
A commercial roof fails over inventory, equipment or a tenant's ceiling. Two visits a year that clear the drains and check the seams cost a fraction of one interior loss.
What causes commercial roof leaks that only appear in heavy rain?
Usually a blocked drain or scupper, a seam that opens under ponding pressure, or a penetration detail that only takes water when the roof is holding depth. Heavy rain exposes drainage problems more often than membrane problems.
That is why the first question on a commercial leak is where the water drains, not where the stain is. Roof drains and scuppers are the most neglected part of most commercial roofs.
Can a commercial roof be replaced without closing the building?
Almost always yes. The work happens above the occupied space, and noisy or odour-producing stages are scheduled outside operating hours. Phased work over weekends is common for retail and offices.
The roof must be watertight at the end of every working day. That constraint drives the phasing more than anything else on an occupied building.
What insulation is used on Oklahoma commercial roofs?
Polyisocyanurate board is the common choice on low-slope commercial roofs, often with tapered panels to create slope toward the drains. Thickness is set by the energy code and by how much slope the roof needs.
Tapered insulation fixes ponding at the source. Adding it during a replacement is usually cheaper than living with standing water for the life of the membrane.
How does hail affect a commercial TPO or EPDM roof?
Large hail can puncture or fracture a membrane and crack the insulation underneath. Damage is often localised and repairable, but a full survey is needed because a puncture can be invisible until it leaks.
Commercial hail claims are usually decided on a grid survey with photographs per section. That survey is the difference between a patch and a replacement.
What is the difference between a roof warranty and a maintenance agreement?
The warranty is the manufacturer's or installer's promise about defects. The maintenance agreement is a paid service that inspects and services the roof. Most warranties require the maintenance to stay valid.
They are sold together for a reason. A warranty with no maintenance record is the easiest claim for a manufacturer to refuse.
Can a flat roof be sloped without replacing it?
Sometimes. Adding tapered insulation and a new membrane is a replacement of the roof surface, not a repair. Small ponding areas can sometimes be corrected with a drain or a localised build-up.
If ponding is widespread and the insulation is wet, the slope correction and the replacement happen in the same job. Doing one without the other wastes the money.
How long does it take to install a new commercial roof?
Most low-slope commercial roofs take several days to a few weeks of working time, depending on square footage, staging, weather and how much deck repair is needed. Phasing and weather extend the calendar time.
We give a schedule with the estimate and update it once the deck is exposed, because deck condition is only fully known when the old membrane is off.
My building leaks over the same spot every spring. What is going on?
A leak in the same place every spring usually means an opening that only lets water in under certain conditions. Wind driven rain, a drain that backs up, or a seam that opens when the roof expands in the heat can all do it. Finding it takes a moisture survey, not a guess.
We look at the flashing, the drains, the penetrations and the seams above the wet ceiling tile. A lot of flat roof leaks in Tulsa track back to a curb or a unit the building owner never suspected. Water travels along the deck before it comes through.
Can you reroof my building while my tenants are still open?
In most cases yes. Commercial work can be staged so one section is torn off and dried in while the rest of the roof stays intact. We plan the sequence around your hours and keep the noisy work away from customer areas where we can. A full closure is rarely needed.
The exception is a building where the roof deck is failing or the tear off would open too much at once. In that case we work in sections and dry each one in the same day. We walk the schedule with the property manager before the crew starts.
Water ponds on my flat roof after every rain in Tulsa. Is that normal?
A little water that drains within a day is common on flat roofs. Water that sits for days is a problem, because it works on the seams and adds weight to the deck. Ponding usually points to a low spot, a clogged drain, or a roof built with too little slope.
We check the drains, scuppers and the slope at the low points. Sometimes a drain is simply blocked by debris. Sometimes the insulation has settled and created a bowl. A coating or a tapered re-cover can correct it, depending on what the survey finds.
How do I know if my flat roof can be patched or has to come off?
It comes down to how much of the roof is wet. A patch works when the moisture is limited to one area and the rest of the deck is dry. If water has spread through the insulation, patching just moves the leak. A moisture survey answers that before you spend money.
We walk the roof, look for blisters, splits and soft spots, and probe where it looks suspect. On a large roof we scan it. The survey tells us whether a repair, a coating or a full replacement is the honest answer. Patching a wet roof is money thrown away.
What is the cheapest flat roof I can put on a shop building in Tulsa?
The cheapest that still works is usually a single ply membrane over a sound deck. Commercial flat roofing in the Tulsa area runs $6 to $14 per square foot installed, and the low end is a straightforward building with good access. A cheap roof on a wet deck fails early.
Be careful with the very low bids. A number that low often leaves out the tear off, the insulation or the flashing details. Compare what each bid actually includes, not just the total. We write our proposals so the scope is spelled out line by line.
Does a metal roof make sense on a commercial building in Oklahoma?
It can, especially on a low slope with a long expected life. Standing seam metal runs $10 to $18 per square foot installed here, which is more than a single ply membrane up front. It handles hail and sun well, and it lasts 40 to 50 years when installed right.
The structure has to carry it and the details have to be right at the panels, curbs and edges. Fasteners and panel movement are where metal roofs fail. On a building where the owner plans to keep it and the roof is replaced rarely, the math often works.
What is a roof drain versus a scupper?
A roof drain is a fitting in the low point of the roof with a pipe that carries water down through the building. A scupper is an opening through the edge or parapet wall that lets water run off the side. Many flat roofs in Tulsa have both, and both clog.
A blocked drain can pond water deep enough to find every weak seam on the roof. A blocked scupper sends water back across the roof and down the wall. Strainers and regular clearing are the cheap fix, and a maintenance agreement covers that check.
Can people walk on my commercial roof for HVAC work?
Yes, with care. Flat and low slope roofs are built to be walked on, but the traffic path matters. Repeated trips to the same unit wear the membrane and open seams. A walkway pad along the common route is a small cost that prevents a lot of repair work.
The bigger risk is a technician dragging a tool or dropping a sharp edge. We see damaged seams and punctures near rooftop units more than anywhere else. If your building has equipment up there, tell us on the survey and we will look at those paths.
What should be in a commercial roofing proposal?
It should name the membrane and how thick it is, whether the old roof comes off or gets recovered, what insulation goes back, how the flashing and drains are handled, and when the work happens. A proposal that only shows a price per square foot is not a scope.
Ask about the warranty in writing, since a membrane warranty and a workmanship warranty are different things. Ask who does the sheet metal and whether the deck gets inspected. We put all of it in writing before a contract is signed, so bids can be compared fairly.
Proof Construction LLC - the facts
- Business name: Proof Construction LLC
- Address: 1709 W Detroit St, Suite A, Broken Arrow, OK 74012
- Phone: (918) 734-4444
- Oklahoma CIB registration: 80004070
- Rating: 4.9 out of 5 across more than 100 reviews
- Workmanship warranty: 3 years, in writing, on replacements
- Manufacturer credentials: Owens Corning Preferred Contractor, CertainTeed SELECT ShingleMaster
- Service area: Tulsa, Broken Arrow, Bixby, Jenks, Glenpool, Owasso, Claremore, Sand Springs, Sapulpa, Catoosa, Coweta, Collinsville, Skiatook, Bartlesville, Muskogee, Okmulgee
- Free documented roof inspections and estimates across the Tulsa metro
Need this answered on your own roof?
Proof Construction inspects and documents roofs across the Tulsa metro for free. No pressure, no obligation, and a written summary of what we find.