What type of tape is recommended for poly seams under basement slab?
KHibbs
| Posted in General Questions on
Looking for recommendations for the best tape to use on poly seams under basement slabs. Can the same tape be used on polystyrene foam board if it is used under the slab?
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Replies
Have you heard of a product called The Barrier?
http://www.thebarrier.com
I have used this before and have liked it. We have used Tyvek tape on XPS foam under slab before as well. I would think pretty much any housewrap tape would work, I'm sure someone will correct me if I am wrong.
Kim,
Here's an article with tape recommendations for a variety of materials, including polyethylene and rigid foam:
Air-Sealing Tapes and Gaskets.
Do not tape under slab. It is not needed. BSC has a very good explanation of this at their site.
In this article: https://www.greenbuildingadvisor.com/blogs/dept/musings/polyethylene-under-concrete-slabs Martin Holliday writes "Some energy-efficient builders misunderstand the purpose of the polyethylene under a slab. They evidently think that the polyethylene is an air barrier, so they go to great lengths to seal every seam with expensive tape and to tape all pipe penetrations... The concrete slab is your air barrier. If you want an airtight floor — and there are several reasons you should, including radon worries — then you need to seal cracks at the perimeter of the slab with high-quality caulk, and you need to seal penetrations through the slab. This work is performed after the concrete has cured."