Wrinkly membrane….

[G and J]

Well, we are back from our week away so it’s back to life, back to reality …

 

And the first question I ponder is what to do about the breather membrane on the front of our house.   For various reasons the front upstairs gable of our house has not had its timber outer skin put on.  Scaffolding has now gone up so that will be remedied soonish.

 

But what to do about the breather membrane?

 

It’s the expensive Tyvek reflective stuff supplied by ETE, the timber frame company.   It’s specc’d for four months exposed.   We’ve been a lot more than that.  It was put up in September.  It now looks a bit like my skin, rather more wrinkly than I’d like.  
 

The timber skin is 24mm larch which overlaps nicely so should keep the vast majority of the rain, etc. out.   I think the main functions of the membrane are to keep wet out of the frame, and to allow water vapour out so that any atmospheric moisture in the timber of the frame can escape.  
 

So do I leave the existing membrane in place and add another layer or is that likely to reduce the passage of moisture too much?

 

Or do I cut the existing stuff away and put new straight onto the OSB of the panels?

 

Guidance gratefully received, as always.

[Redbeard]

Perhaps ask the UK importers (?) of Tyvek. They will probably take the pessimistic view and tell you to replace (which I think is the way I'd err)  but if they suggest another course (leave it, or add A.N Other membrane) then you may have saved some time and a bit of extra cost.

[G and J]

Thank you Redbeard.  My thinking is that if there isn’t a downside to simply adding another layer them why not do that.  Reduces probability of leaks perhaps.  But logic doesn’t always work with building…