Why Flashing Cement VS Urethane

OT , but is flashing cement the general material of trade that ya’ll use when sealing around perimeter edges, detailing about penetrations, etc.

I’m going through a full teardown, and just short of asking a roofer to do what is normally not akin to using , IMO I feel urethane stuff from Tremco, Dymonic, etc are FAR superior products to use. The 2 part urethanes are even better than the tubes/sausage rolls.

Different product density I suppose. But urethane lasts and does not dry out. Might even handle expansion/contraction more.

Regular Plastic cement (tar) is not supposed to be exposed, if you are going to caulk something were the caulk would be exposed you would want something other than plastic cement.

I like Urethane if it is going to be exposed.

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Tar regardless dries out though ? Granted, I don’t know if the flashing roofing cement that is in a tube is different that the traditional stuff ya’ll trowel on.

I’m looking at my neighbors roof. They used flashing on the entire parapet. It’s one big black wall .They stopped short with 1 sheet width to the ridge and decided to not cut another strip to reach the top of ridge. About 8-10 inches wide flashing. All spiderwebby, dried, cracking. Granted, any decent roofer is only minimally using it for edge treatment.

I’ve used Urethane around the house for stuff. The 2 part mix is more work, but it’s night and day difference than the stuff in tubes/sausage - and alot of people/trades use the single part just due to convenience and it works imagine. Imagine how much better the 2 parts will be ontop. The good urethanes works. They don’t dry out like tar, they hold like he11, and most important of all, they deal with expansion/contraction nicely as well.

I suppose I’m on my soapbox perhaps.
To me it’s a far superior product in general.
Was kurious if any of ya’ll use this more as a ~upcharge~ on a install if the customer is willing to pay for it - which to me, is cheap in the grand scheme of things

Do it right or why do it at all.
I don’t got to a restaurant and tell them what ingredients to use.

However, I do feel urethanes are better than tar…

It depends on what you are using it for.

For Modified Bitumen you do not use plastic cement, it is not compatible.

For Mod Bit roofs you use Neoprene, it is black and can easily be mistaken for plastic cement, until you look at the price.

Neoprene can be exposed to the sun