PERSIST + Rainscreen siding issues
I am in the final phase of completing my first PERSIST remodel.
We have installed (2) layers of reclaimed 2″ polyiso on the walls (over TYVEK drainwrap) of a 1940’s ranch and then strapped with 1×4’s using headlock screws. Existing walls were in decent shape in terms of flatness and corners were within an 1/4″ of plumb over 10′. So the walls were not perfect but they were pretty good, not bad enough to catch the eye.
The strapping however is extremely wavy. I think my first issue was using 1×4’s when I probably would have been better off using 2×4’s. But I can’t change that now because I have already built out my window openings to accommodate the insulation and 1x. If I switched to 2x the window trim would be coming up 3/4″ short because my total wall thickness will have increased. The 1x pulls in tight at each screw, which we installed at 16″o.c. but still bulges between screws where insulation has not been compressed as much. I do not have the budget to double the number of screws used.
So i feel like I am left with (2) options:
1) Check corners vertically with a string and make sure they are straight. Then pull strings at the bottom top and center point of the wall horizontally and rip a shim for each vertical 1x. Then install siding.
2) Check corners vertically with a string and make sure they are straight and pull a string as I do each coarse of siding and shim between the siding and the furring.
Both are fairly labor intensive but I think #1 will lead to a better install.
Any other ideas or experiences with this problem!!!!!!
Thanks for any help.
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Replies
What cladding system will be used ?
What is the distance between each screws on the 1X4 ?
In cases like that you usually end up with 2 solutions ..
addtional material/fasteners = $$$$$
or additional labor ( diy??) = time
Yes you should've used 2X4 for that.
Total wall area ??
I was told by and old guy to always fixed the base problem before reverting to shimming
(unless it is a matter of minutes ) if possible . Always worked good for me up to now.
Additional : you say you are going for a PERSIST type, what did you use as moisture/seal between the warm inner wall and the insulation ?
Charles,
Have you tried backing off the screws that are creating low spots because they are too tight? I suggest that you use a 4-foot aluminum straightedge to verify whether the furring strips are co-planar as you back off some of the screws.
Sometimes reclaimed foam isn't of perfectly uniform thickness creating a bit of wave in a double-layered stackup. Backing off the screws (even shimming out to true it up a bit if you have to where it's really far off) should work OK.
I had not suggested backing off screws because it seemed like obvious that it was tried and was not working and did not want to insult anybody here :p
So question remains, have you tried backing off screws a bit already ?? :p
Thank you all for the feedback.
I will play around with backing out and tightening screws as needed. And in the future I will try 2x4 strapping for the rain screen.
Another issue is that the plywood corners we used do not pull in as tight as the furring, I guess due to the larger surface area. I will try and back out the 1x4s a little to meet the face of the corners.