Flat & low-slope replacement · Lee County, Florida
A flat roof
isn't flat. That's
the whole point.
Every low-slope roof is built with just enough fall to get water off it. When it stops draining, the membrane stops being the problem and the water becomes one. Most flat roof failures in this county are drainage failures wearing a membrane's clothing.
If you take one thing from this page: water standing on your roof forty-eight hours after rain is ponding, not drainage. It voids warranties, it doubles the ageing rate of most membranes, and putting a new membrane over the same bad fall just restarts the clock on the same failure.
- Free, with no obligation
- Written report with photos
- Office on Cypress Lake Drive
The systems
Four ways to cover a low-slope roof.
They are not interchangeable, and the right answer depends on what's underneath and what happens on top of it.
TPO — the default, and usually the right one
A single-ply thermoplastic sheet, usually white, with seams hot-air welded so the joint is effectively as strong as the sheet. Reflective, well understood, widely available, and priced sensibly. It has become the standard low-slope covering in Florida for good reasons.
The variables that matter: sheet thickness (typically quoted in mils — thicker is more puncture-resistant and costs more), and how it's attached.
PVC — when there's grease or chemicals
Similar single-ply approach with welded seams, but the material resists oils, fats and chemical exposure that degrade TPO. If your roof has kitchen exhaust on it — a restaurant, a commercial kitchen — this is the specification, and putting TPO up there instead is a false economy measured in years.
Modified bitumen — multi-ply, and tough underfoot
Rolled asphalt-based sheets in two or more plies, torched, hot-mopped or self-adhered. More layers means more redundancy, and it takes foot traffic better than a single-ply — worth considering on a roof where equipment gets serviced regularly. Heavier and more labour to install.
Coatings — legitimate sometimes, oversold often
A fluid-applied coating over an existing sound membrane can genuinely extend its life and reduce heat gain. Over a membrane that is wet underneath, it seals the moisture in and destroys the insulation while looking fine from the ground for two years.
The honest test is a moisture survey of the existing assembly before anyone quotes a coating. If someone offers to coat your roof without checking whether the insulation is wet, they are selling you two years.
Drainage
The part nobody quotes and everybody needs.
Low-slope means sloped
Roof drainage requirements mean a low-slope roof is designed with fall to its drains or scuppers — commonly a quarter-inch per foot. Decks settle, insulation compresses, and additions get built with optimistic framing, so plenty of existing roofs no longer have the fall they started with.
Ponding is a diagnosis, not an aesthetic
The working definition is water still standing forty-eight hours after rain stops. It accelerates membrane degradation, it grows biological gunk that holds more water, and the weight of it deflects the deck further, which deepens the pond. It is also excluded from most membrane warranties, which tells you what manufacturers think of it.
Tapered insulation is how it gets fixed
Rather than rebuild the structure, fall is built back into the roof with insulation cut to a taper, laid to direct water to the drains. It adds cost and it adds R-value, and on a roof that ponds it is the difference between solving the problem and covering it up.
A flat roof quote that says nothing about drainage on a roof that currently ponds is not a quote for fixing your roof.
Drains, scuppers and overflows
Clogged drains cause more low-slope failures than bad membranes. Strainers, adequately sized outlets, and a secondary overflow path so that a blocked drain doesn't turn the roof into a paddling pool — a few hundred pounds of standing water is a structural matter, not a housekeeping one.
Specification
What separates two low-slope quotes.
How the system is attached
Mechanically fastened, fully adhered, or a hybrid. Fully adhered generally performs better under wind uplift and costs more; mechanically fastened is quicker and shows the fastener pattern as slight ripples in the sheet. In a hurricane-exposed county the attachment method is the single most consequential line on the quote, and it should be stated along with the approval it's installed under.
Tear-off or overlay
Going over an existing roof is cheaper and traps whatever moisture is already in the assembly. There are also limits on how many layers can stay. If an overlay is proposed, the reasonable question is what moisture survey supports it.
Insulation, stated as a thickness and an R-value
On a low-slope roof the insulation is part of the roof rather than something in an attic, so it's on the quote — or it should be. Cover board over the insulation protects the membrane from foot traffic and improves the wind performance of the assembly. It's a line that quietly disappears from cheaper quotes.
Every penetration and curb, detailed
AC units, exhaust fans, vent pipes, skylights, parapet walls. Low-slope roofs leak at their edges and their penetrations almost exclusively, and the flashing detail at each is where the skill and the money go. A quote that prices the field of the roof and waves at "flashings as required" is hiding its largest variable.
The warranty, and what kind it is
A material warranty covers the sheet. A system warranty covers the assembly. A workmanship warranty covers the installation. Manufacturer system warranties usually require an approved installer and an inspection, which is a meaningful quality signal — and ponding is generally excluded from all of them.
Residential low-slope
The Florida room, the lanai and the carport.
Most low-slope roofing in Lee County isn't a commercial building — it's a section of a house. An enclosed Florida room, a patio cover, a carport, or the flat run where an addition meets the main roof.
Those transitions are the single most common leak location on a Florida house, because they combine a low-slope membrane, a wall junction and usually an addition built by someone in a hurry. Water gets behind the flashing where the low roof meets the wall of the taller one, and it shows up inside a long way from where it entered.
Two things go wrong repeatedly. Shingles get run down onto a slope too low to shed water, because someone wanted the roof to match — asphalt shingles have a minimum slope and below it they leak regardless of how well they're laid. And the wall flashing gets surface-sealed instead of being taken up behind the wall covering, so it works until the sealant fails.
If the leak in your house is near where a flat section meets a wall, it's worth having that junction looked at specifically rather than having the whole roof quoted.
Worth knowing. The secondary water barrier requirement that applies to steep-slope re-roofs has an exception for slopes under 2:12 with a continuous roof system — which is what a properly installed low-slope membrane is.
That's why a flat roof quote reads differently from a shingle one. It isn't a corner being cut.
Questions
Flat roofs, answered straight.
How long does a flat roof last in Florida?
It depends far more on drainage and attachment than on the membrane brand. A well-drained, well-detailed single-ply on good insulation has a long service life here. The same membrane on a roof that ponds will not, and no warranty will help you.
Can I just have it coated instead?
Only if the existing assembly is dry and sound. A coating over wet insulation seals the water in. Ask for a moisture survey before anyone prices a coating — if they won't do one, that answers the question.
Why is there always water on my roof after rain?
Some residual water in low spots is normal for an hour or two. Water still there two days later is ponding, and it means the roof no longer drains as designed. That's a fixable problem, usually with tapered insulation, but it has to be priced as part of the job rather than ignored.
TPO or modified bitumen for my Florida room?
Either can work. TPO is lighter, reflective and quick; mod-bit has more plies and takes foot traffic better. On a small residential section the decision often comes down to how the edges and the wall junction are detailed, which matters more than the sheet.
Does a white roof actually reduce my cooling bill?
A reflective membrane reduces heat gain through the roof, and on a low-slope roof directly over conditioned space that's a real effect. How much it shows on your bill depends on your insulation and your ceiling. Anyone quoting you a percentage saving without looking inside is guessing.
My flat roof leaks but the membrane looks fine.
Then look at the edges, the penetrations and the wall junctions, in that order. Membranes rarely fail in the middle. This is also why chasing a flat roof leak by looking directly above the stain usually fails — water travels a long way between the membrane and the ceiling.
Is this a commercial job or a residential one?
The materials are the same; the scale, access and scheduling aren't. If it's a commercial building with tenants and rooftop equipment, that's a different conversation.
Should I get a wind mitigation inspection afterwards?
Yes, if the low-slope section is part of your home's roof. The attachment and barrier details are what earn credits on form OIR-B1-1802, and they only count once they're documented.
The rest of the cluster
A different covering is a different conversation.
Each material fails in its own way and carries its own set of questions worth asking before you sign anything. These cover the other three.
Shingle roof replacement
The common one, and the one where the underlayment specification matters more than the shingle brand. Three legal ways to build the secondary water barrier; they do not perform alike.
Metal roof replacement
Standing seam or exposed fastener, and the difference decides what you are maintaining for the next thirty years. Coastal corrosion, finish grades, and what a system approval actually covers.
Tile roof replacement
The tile is a rain screen; the underlayment beneath it is the waterproofing, and it is what expires. Often a lift-and-relay rather than a replacement.
Where we work
Getting a flat or low-slope roof quoted in Lee County.
Four cities, and the roofs in them do not age the same way — nor does the permit go to the same desk. Each page covers what is specific to that one.
Fort Myers roofing
Home base, on Cypress Lake Drive.
Cape Coral roofing
Open canal lots, so edges and corners take the wind first.
Estero roofing
Mostly tile, and mostly inside communities with a say over it.
Bonita Springs roofing
Closest to the Gulf, so corrosion arrives early.
Outside these four? Call and we will tell you straight whether we can reach you on the day you need us, rather than claim a service radius we cannot cover. All service areas.
Book it
Start with why it's failing, not what to put on it.
Three short steps and we'll arrange it. The inspection is free, you keep the photographs and the written report, and on low-slope roofs it often finds a drainage problem rather than a membrane one.
Get it in writing before you commit.
About an hour on site, photographs of every problem area, and a plain answer about whether this is a repair, a replacement, or a drainage fix.
Get an inspection arranged