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Community and Q&A

Liquid Flashing Products

happycanuck | Posted in General Questions on

Hello all, hoping someone can point me in the right direction. In the Toronto area, Ontario. I need a prosoco/zip type STPE liquid flashing product to start sealing up gaps and rough openings in the cottage I’m in the process of self building.

Struggling to find anything easily obtainable at a reasonable price that is like prosoco fast flash here – the closest locally available equivalents I’ve dug up are the Sika Hyflex 150 (I can get via Amazon easily, about $27/sausage) and the tremco dymonic 100 (local supply store keeps it, about $13/sausage).

Are either of these a good or suitable substitute for prosoco type liquid flash? I know the tremco is poly rather than STPE ( I believe STPE is the more proven way to go), the Sika I think maybe STPE but despite reading all the docs am unsure. They describe it as a single ingredient elastomeric so it sounds like it might be what I want.

Thanks in advance any advice is very much appreciated.

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  1. Expert Member
    Michael Maines | | #1

    Is there a reason you aren't using Prosoco or Zip LiquidFlash?

    1. happycanuck | | #2

      Michael, in answer yes - I just can't find anywhere to buy them in Canada. Theres 2 Canadian websites that mail order the prosoco, but they're both about $35-$40/sausage from memory, and the shipping was horrendous like $100 :(

      Thus, I started trying to find more readily available alternatives.

  2. happycanuck | | #3

    A better phrasing of my messily worded question I guess, is "are either tremco dymonic 100 or Sika hyflex 150 suitable alternatives to prosoco fast flash"? :)

  3. Dan S | | #4

    Henry Air-Bloc Liquid Flash, which is STPE, is apparently distributed in Canada

    In fact, Scarborough ON appears to be Canadian HQ (Global HQ is in California), so you could probably drive or even take the bus there to talk to them :)

    I didn't use it on my house, but I had a good experience with their Blueskin VP100 adhesive membrane, FWIW.

  4. Expert Member
    Akos | | #5

    If you are using ZIP/OSB/CDX, I would do most of the sealing with their tape and only use liquid flash for the problematic joints (ie foundation to Zip or head flashing above windows/doors).

    My local lumber yard (Downtown Lumber) stocks Zip liquid flash, I'm sure the larger yards outside of the city would also carry it or be able to order it in. Not cheap though, more reason to only use it where absolutely needed.

  5. happycanuck | | #6

    Thanks Dan for the suggestion, I'll contact them. I did find the air bloc lf product, but again couldn't find anyone locally or even online to actually buy it from.

    Despite the widespread use of liquid flashing in the US and all those Matt risinger videos I've been watching, all the products seem incredibly rare here :s

    1. Dan S | | #7

      I didn't use any liquid flash, but I taped sheathing joints and went over those with an fully adhered membrane. My builder used Protecto Wrap flashing on the window frames. On the foundation-sheathing gap, first I caulked it, then primed and applied Siga Wigluv tape. I'm sure liquid flash would have worked even better than those approaches, but liquid wasn't as cost effective or easy to install for a beginner like me.

      Matt Risinger makes everything look really easy, but he's a high end custom builder, not a DIY air sealer.

  6. Jamie B | | #8

    I'm also in Toronto, and scoff at the difficulty of getting Prosoco products.

    I'm a big fan of PU's like dymonic 100 and sikaflex. I know you're preferably looking for a STPE, but dymonic 100 is still high performance and I enjoy it's durability (I haven't had the chance to test an STPE, so what do I know). The only thing I don't like about dymonic 100 is It's thickness. Usually that's good for controlling your beads and tooling joints, but it's hard on your hands to pump and trowel flat if you're doing a lot of it. I find sikaflex is a bit thinner so I can trowel it easier.


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