Tuck Tape Test
A little something for us Canucks North of the border. Up here, good old “Super Six” poly is used almost exclusively in new construction as a vapor barrier. (That’s code official speak for vapor retarder.)
As has previously been discussed here, our venerable red Tuck Tape air sealing tape has recently gone through an upgrade. We now have a blue version of Tuck Tape (CONTRACTOR’S SHEATHING TAPE for PE VAPOR BARRIER), which claims to use a new acrylic adhesive for 50% more adhesion than the old red version (60 oz/in vs. 40).
http://www.cantech.com/product/286
I’ve used red Tuck Tape in the past and have been underwhelmed with its adhesion to poly vapor barrier. Just now I went into our furnace room and, with a quick tug, was able to pull red Tuck Tape off of poly that’s been there for years. It pulls clean off with little effort once started, and leaves no adhesive residue behind.
You can see in the close up picture, the blue tape is quite a bit thicker than the red tape (4.1 vs. 3 mil). The bulk of that added thickness seems to be from additional adhesive; the blue roll is quite squishy and is really wavy, while the red roll is much firmer.
So I set up a little test to see if the new blue is all it’s cracked up to be. I stuck four pieces of poly on poly with the same amount of tape (measured), two with blue and two with red. I was planning to peel two and shear two and see what the difference is, gauged with a pull strength meter.
Question: do you think peeling a relevant test or should I just try to pull it in shear?
Their adhesion specification doesn’t specify if that’s a straight pull test, peel test or a shear test. Looking a the CCMC eval report, it would seem the testing is done in shear as they claim the polyethylene failed before the tape bond in one test.
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Replies
I would think you’d want to do both tests.
The tape is likely in shear over the long term, since it’s holding the poly under some tension. Your long-term failures of the tape would probably be due to shear forces, so testing for that would give an idea of the long-term performance of the product.
The tape is likely to fail by peeling during construction. I’d expect most damage would be from things rubbing or dragging over the tape during construction, which would likely catch on edges and corners and work to peel the tape off the poly. Testing for peeling resistance would give an idea of how well the tape would hold up in the short term, to the types of temporary and accidental forces it would likely encounter during construction.
Bill
I am also curious about the blue tape for PE, whether this is good for sealing the seams of wood sheathing. I know I can use the white or red tape for wood. I'm not sure if they changed the chemistry so the blue is reformulated for PE plastic, or if it's mostly the same as the white or red tape but they just made it thicker with more adhesive.
The pressing question for Canadian builders is whether the blue tape sticks to your teeth the way the red does?
Malcolm,
The blue sticks to your teeth much better than red. Also the adhesive tastes worse than red (which is obviously a sign of better adhesive)
Blue tuck is the way to go for only $2 more per roll. But red is still useful fixing broken tail lights!
Jamie,
Great to know! Hopefully it's also easier to find the end of the roll.