Who cleans TPO roofs in Austin?
Live Oak Exterior Cleaning cleans TPO and other flat roofing across Austin and Central Texas. TPO roofs are soft washed: an algaecide does the work and a low-pressure rinse carries it away, which stays well under the pressure ceiling the membrane manufacturers publish and keeps force off the seams. We are fully insured and provide a certificate of insurance for every commercial engagement.
A white roof shows everything growing on it
TPO, thermoplastic polyolefin, is the white single-ply membrane on most flat and low-slope commercial roofs built in the last twenty years. It is specified white on purpose, to throw heat back off the building rather than hold it.
That is also why it looks bad so quickly. Algae needs moisture and shade, and a flat roof supplies both: water that sits after rain, shade thrown by a parapet or a rooftop unit, drainage that moves slowly. Austin's humidity does the rest. On a dark shingle roof the growth takes a while to read. On a white membrane it reads immediately.
Why pressure is the risk on a membrane roof
A single-ply roof is a sheet of plastic that keeps water out because of how it is joined and sealed. Everything that makes it watertight is a detail that pressure can open.
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Seams are the whole roof
A TPO roof is watertight because its sheets are welded to each other. A high-pressure stream aimed along a seam works against that weld, and a seam that starts to lift does not announce itself until there is water in the building.
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Fastener plates sit just under the surface
The membrane is held down by plates and fasteners beneath it. Pressure concentrated over one is force applied exactly where the sheet is already stressed.
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Flashings and details are hand-made
Corners, curbs, drains and pipe boots are detailed on site rather than factory-welded. They are the most individual part of the roof and the least able to take a pressure washer.
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Chemistry removes what force only moves
Algae pushed off a surface with water grows back from what is left behind. An algaecide kills it, which is the difference between a roof that stays clean and one that looks cleaned.
The number to ask about
The membrane maker publishes a ceiling
Carlisle, whose Sure-Weld membrane is on a great many of these roofs, publishes a cleaning procedure for it. A pressure washer may be used at no more than 2,000 psi, through a 40-degree fan tip, held at least twelve inches off the membrane. Above that, the document says, the water abrades the surface and washes out the light stabilizers that protect the membrane from the sun.
A soft wash sits far below that ceiling, and that is the point of quoting it. The number is a limit rather than a target, and it gives you something to ask any contractor bidding your roof. A crew that cannot tell you what pressure they intend to use, through what tip, at what distance, is a crew deciding it on the roof.
How the clean runs
- 01
Walk the roof first
Where the growth is, and why that part of the roof holds water. A low spot or a shaded run behind a rooftop unit will go green again whatever is done today, and you should hear that before the work rather than after it.
- 02
Settle where the water goes
The drains on a flat roof lead somewhere, and that is worth agreeing before anything is applied rather than discovering afterward.
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Apply at low pressure
The cleaning solution goes on at low pressure and is given time to work. The chemistry kills the growth at the root. The water is there to carry it away, not to remove it.
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Rinse clean
A gentle rinse lifts the dead growth without putting force on the seams, the fastener plates or the flashings around drains, curbs and pipe boots.
Where this sits in the rest of the work
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The method, in full
Why soft washing beats pressure on anything with growth on it, and which surfaces take which.
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Pitched and shingle roofs
The same chemistry, on the composition, tile, metal and cedar roofs that are not flat.
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The rest of the building
Facades, windows, flatwork and structured parking, each cleaned by the method that suits the material.
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Facade and building washing
Stucco, precast, brick, metal and composite panel, phased around the people using the building.
Common questions about TPO roof cleaning
Who cleans TPO roofs in Austin?
Live Oak Exterior Cleaning cleans TPO and other flat roofing across Austin and Central Texas. TPO roofs are soft washed: an algaecide does the work and a low-pressure rinse carries it away, which stays well under the pressure ceiling the membrane manufacturers publish and keeps force off the seams. We are fully insured and provide a certificate of insurance for every commercial engagement.
How do you clean a TPO roof?
With a soft wash. We apply an algaecide, sodium hypochlorite, which kills the algae growing on the membrane, then rinse at low pressure. The chemistry does the cleaning and the water only carries it off. This is the same method we use on shingle roofs and for the same reason: the growth has to be killed at the root rather than blasted off the surface, or it returns within a season.
Will cleaning damage the membrane or the seams?
Not the way we do it. The risk on any single-ply roof is pressure, not water. A seam, a fastener plate or a flashing detail is where a flat roof is sealed, and a high-pressure stream aimed at one is how that seal starts to fail. Soft washing never puts that pressure on the roof, which is why it is the method we use on TPO.
Why has our white roof turned green or black?
Because something is staying wet on it. Algae needs moisture and shade, and a flat roof gives it both wherever water sits after rain, wherever a parapet or a rooftop unit throws shade, and anywhere drainage is slow. Austin's humidity does the rest. The growth shows most on a TPO roof because the membrane is white and anything growing on it is immediately visible.
How much does TPO roof cleaning cost in Austin?
It is priced by scope. What moves it is the roof's square footage, how it is reached and whether equipment has to be carried up, how much growth has taken hold, the number of rooftop units and details to work around, and whether the work has to happen outside business hours. We walk the roof or review plans, then put a written proposal in front of you.
How often should a commercial flat roof be cleaned?
It depends on how fast the growth comes back, and that is a question about shade and drainage rather than about the calendar. A roof with good fall and open sky stays clean far longer than one with ponding areas and tall screening around the rooftop units. We would rather look at the roof and tell you what it needs than quote an interval that fits every building and none.
What other flat roofing do you clean?
Modified bitumen and metal, alongside TPO. Each one has a method that suits it and a method that damages it, so we match the approach to the material rather than running one technique across the whole roof. Live Oak Exterior Cleaning cleans the full range of commercial exterior surfaces across Austin and Central Texas, roofing included.
Have a flat roof that needs looking at?
Tell us about the building and we will walk the roof and put a written proposal together.
Rather talk it through? 512-883-5420