Gaco western polyurethane foam roofing

Tomorrow I’m inspecting a house with sprayed polyurethane foam coating on the roof. It has been sprayed over concrete tile. Any tips?


Yeah, don’t walk on it. Are you sure it is SPF…Gaco is a silicone coating.

See attached permit. They permit title on the previous page called out spray polyurethane coating. Here is the permit:

So no walking on?

Ensure that it has a good coating system, uniformly installed. Areas left uncoated or with thin coats will deteriorate. Look for locations with bubbles or poor adhesion. Look for areas holding water. Any leaks are typically isolated to and occur from small, pencil lead sized holes. Birds will also tear the foam trying to get to bugs.
IMHO, the roof age is determined by the coating system. If the seller can show you proof of the top-coat product applied and if it appears to have been properly installed, this determines the age and life expectancy of the system.
For example, Lanco Urethanizer states a 15 year warranty. If newly installed, I would say that the roofing system should last approximately 5-7 years before maintenance or re-coating is required.

That roof contractor does a lot of SPF roofs in Pinellas. They must have just used a thin foam spray on the tile, and then top coated it with Gaco silicone. Not really sure why, because the real roof system is under the tile…

Any yes, I would not walk it.

I’d walk it without an issue. Just make sure it is not slippery.

Cheaper to coat than reroof?

It appears as though this is just a spray or roll on roof coating, similar to elastemeric coating. A waste of time as Brad pointed out, the actual roof is underneath.

If you are going to coat the roof properly, there is a 7-step process using a slurry mixture and then the last coat is the poly coat.

What they did there happened to a bunch of people who had older roofs in Tamarac. It covered up a bunch of leaks and rotted wood on 30 year old roofs. The association tried to sue the roofer…but surprisingly…he was no longer in business after charging 4 grand and doing all 250 roofs in the neighborhood. :shock:

No worries about walking on it.

Ok, I’ll follow up with some pics later. I’m interested to see what kind of coating can cover every nook and cranny of a tile roof well.

I few things to consider:

This product has an NOA, I didn’t see a PA but it may exist, the NOA states the product is not to be applied over “concrete or clay tile”. I would have second look around for the approvals as I only did it briefly.
***R903.1 General.
*Roof decks shall be covered with approved roof coverings secured to the building or structure in accordance with the provisions of this chapter. Roof assemblies shall be designed and installed in accordance with this code and the approved manufacturer’s installation instructions such that the roof assembly shall serve to protect the building or structure.

The second issue at hand is that the FBC requires that the roof covering be attached according to the current code requirements or recovering/roofing is in violation…**708.1.1
** Not more than 25 percent of the total roof area or roof section of any existing building or structure shall be repaired, replaced or recovered in any 12-month period unless the entire roofing system or roof section conforms to requirements of this code.

It appears as though this product qualified and had a Florida Product Approval via the NOA, so the Miami-Dade NOA was the only source for installation. And as such, requires installation according to the NOA…the FBC: HVHZ protocols. The type/name of the actual product wasn’t listed in your post so I read a few and all of them achieved Florida PA through the NOA. If you have more specific details that would really help.

But for now, this is what the NOA will reference as far as the building code: [FONT=Times New Roman][size=2][/size][/FONT]
[FONT=Times New Roman][size=2]**1521.16 **[/size][/FONT][FONT=Times New Roman][size=2]No recover application shall take place over existing[/size][/FONT]
[FONT=Times New Roman][size=2]wood shingles, shakes, slate, tile or metal shingles.

The roof was too slippery to walk on this morning but I got lots of eaves shots. The coat looks to be about 3/4" thick with a slight give to it when pressed. I’d still unclear if there is “foam” here or if it is just polyurethane coating (and the permit was written wrong)??

Thanks for the photos. That roof has definitely been spray foamed and sealed with Gaco. This must have been an attempt to extend the life of a slightly leaking roof system…did it work?

I wouldn’t have walked it even if it was dry, but I don’t walk tile roofs anyway.

It’s a coating Robert, not a roof covering. I am sure you know the difference. But, you can keep on quoting those non-applicable codes if you want to.

No stains in the attic. This is part of a 100+ complex of duplexes all with the same coating.


Just for the heck of it…would the applied coating now be the primary WPM and the membrane below the tile become the SWM on a wind mit?

No. The underlayment membrane is still the primary roof covering for a tile roof. The tile acts as ballast and a UV protectant. The tile just protects the roof covering, and in this case, the coating protects the tile. For the 1802, the definition of SWR does not change…PnS directly on the sheathing.

I do hope they didn’t cover up the weep holes at the eaves on this coating job.

About 90% were still open. Some were plugged.