Taping sheathing vs housewrap – which do you prefer and why?
jollygreenshortguy
| Posted in Energy Efficiency and Durability on
A question for builders and building science geeks –
Part of achieving a good air barrier involves taping all the laps of housewrap on walls.
What are the pros & cons of taping the sheathing joints instead, before housewrap installation?
Also, roof sheathing could be taped the same way. I know there’s more to a full air barrier system (doors, windows, penetrations…) but I just want to focus on the one point of taping. Thanks.
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Replies
IMO, taping the house wrap is wasted effort. But fully adhered house wrap (or roof underlayment) is beneficial.
> What are the pros & cons of taping the sheathing joints instead, before housewrap installation?
It's easier to detail sheathing with tape to be an air barrier than it is to turn a normal (i.e. non-self-adhered) WRB into an air barrier. So much so that I would never try to use a normal WRB as an air barrier.
There's also a risk that when you tape WRB seams, you're potentially creating pockets where incidental water could get trapped and held against a material that should not have standing water against it (the sheathing).
Antonio,
Taped house-wrap is a very poor air-sealing strategy. You are much better off choosing either the sheathing or an interior membrane as your primary air-barrier and 0nly taping the house-wrap in areas where it will help preclude water infiltration.
Using the sheathing as the air-barrier doesn't work with vented roofs, and is seldom the best choice on un-vented ones either. You want something closer to the interior.