KEE is a heat-welded single-ply membrane made from PVC blended with a ketone ethylene ester resin that keeps the sheet flexible without relying as heavily on plasticizers. In practice, that means strong resistance to grease, oils, chemicals and UV, which is why it shows up on restaurants, food plants, labs and buildings with heavy exhaust. It costs more than standard PVC or TPO, so it makes the most sense where a roof sees harsh exposure. We compare it with a standard PVC roof on the same building so you can see whether the upgrade is worth it.
The estimate names the exact membrane, its thickness and the accessories we plan to use.
Before welding new KEE to an existing roof, we confirm what the current membrane is and check the seams. Salt air around Ventura Harbor is hard on metal accessories, fasteners and edge metal, so we note their condition separately. Every project starts with the owner or manager naming the roof area and the person who will meet us. We follow the building's access rules, and our inspection results are what we base the recommendation on.
Records and what we find on the roof
KEE roofs come from a small number of manufacturers, and each has its own sheet, flashing products and approved details. If you have records from the original install, they help us match materials. We also inspect the roof to check the membrane, the welds and any patches. Parts of the roof we cannot access are called out.
A test weld tells us whether an unknown patch will take new KEE or has to be cut out.
A commercial roof inspection catches surface wear, failed welds and loose edges. Cores answer what is happening below, and we take them away from traffic areas so the patches stay out of harm's way. A moving wall or sagging deck gets sent to an engineer before we plan around it. On food plants and labs, we also ask what gets vented onto the roof, since that decides how much the chemical resistance matters.
What can stay and what gets replaced
A new KEE membrane needs a firm, dry base. Crushed or wet boards found with infrared and cores are swapped for new insulation and cover board. Dry, well-attached material can usually stay, which keeps cost down. Where the old roof stays under a recover, we check that it is flat and sound enough to support the new sheet.
Untested areas stay as open items in the price until we can get to them.
Extra wet insulation found after opening means a phone call to you before the crew keeps cutting. Bad deck gets its own photo and its own price, and we wait for your approval before replacing it. That way the estimate matches the actual condition under the membrane, and there are no surprises once the old roof comes off. Core holes are welded over before we leave.
Curbs, drains and tie-ins to other roofs
KEE welds well to itself and to compatible PVC-based products, but not to TPO, EPDM or asphalt roofs. Where a KEE section meets a TPO roof or another system, the two meet over a raised curb or a transition piece the manufacturer approves. Curbs, drains and exhaust fans get KEE flashing welded in place, with preformed corners and pipe boots from the same product line.
Each weld is probed after it cools to check for gaps.
Grease from kitchen exhaust is one of the main reasons owners choose KEE, so we pay close attention to the area around those fans. We recommend a grease containment box on the fan and a sacrificial walk pad below it. If a new roof raises the surface, we check curb, drain and door threshold heights before installing it, so the flashings have the height they need.
Related Roofing Work
Getting the roof ready to work on
Before we start a section, the roof has to be ready: rooftop units disconnected if needed, plumbing at the drains handled and any structural repairs done. We track readiness zone by zone in our roof condition reports. We only open sections we can close the same day.
If an area is not ready, it waits, and the rest of the roof stays watertight in the meantime.
Mechanical, plumbing and electrical work on the roof is handled by those trades, and we coordinate timing with them. Shutdown times are the building's call. Deliveries and debris removal are planned around tenants and customers. The owner sees one schedule that shows the roofing and the other trades in the right order, so nobody arrives to find the roof not ready for them.
Closeout and later reviews
Closeout includes photos of the new KEE, its welds and flashings, any board or deck we replaced and the product data. We note where each section starts and ends, what it ties into and where any temporary protection was used.
Around Downtown Ventura, where roofs often carry decades of patches, we mark the ones we left.
A future commercial roof replacement review starts with a clear map of what is new KEE and what is older roof. Open items from other trades and mid-job changes are on a separate page. That gives the next decision about the roof a clear starting point, whether it is a repair, a recover or a full replacement.
A KEE roof should be checked against the actual manufacturer's system and accessories, especially where it meets another membrane or metal edge. We confirm the sheet, reinforcement, attachment and welding method from current product documents rather than treating the resin name as the whole roof system. At curbs and drains, we use the manufacturer's flashing details and check the surface they attach to. If someone proposes a substitute product, we compare the documents and details before accepting it. Two flexible sheets can look the same and still perform very differently at the transitions.
Common Questions
How do you compare KEE with other roof options?
We price KEE, PVC and other systems using the same inspection results, repairs and insulation work. The difference then comes down to the membrane itself: how well it stands up to grease, chemicals and salt air on your roof, and how much more it costs.
What gets checked before ordering materials?
We confirm the existing membrane, the condition of the insulation and deck, any unknown patches and the manufacturer's approved details. Anything still unknown is listed in the estimate so it is settled before materials are ordered.
What happens when the new KEE roof meets a different roof system?
KEE will not weld to TPO, EPDM or asphalt, so the joint is made over a curb or with an approved transition piece. We also check drain and curb heights if the new roof is thicker than the old one.
What should the closeout include for future roof work?
A photo set, product sheets, section boundaries and a short list of open items. That helps the next roofer plan work without guessing.
Find out if KEE is right for your roof
Let us know the address, which roof you mean and what kind of exposure it sees, such as kitchen exhaust or chemicals. We will inspect it and give you an estimate that compares KEE with other options and shows exactly what the work includes.