Screwing Ipe to plywood siding
I have another thread that I posted a week or so back the led into this question, but I think it may have gotten a little jumbled so just wanting to re-post it. I am installing Ipe open cladding in a couple of 10’x10′ areas of my house. I was planning on placing battens directly over the studs within the wall and then screwing the Ipe through the battens and sheathing and 1.5-2″ into the studs. However, I came to find out that the studs aren’t at ideal locations and the result would be screw locations that aren’t symetrical and on some of the boards the nearest connection point from the end could be 12″.
If I could just screw into the plywood sheathing and not worry about hitting the studs I could then locate the battens anywhere which would provide regular and consistent attachment points. I am just concerned that 1/2″ plywood might not be a suitable fastening material for Ipe. I suppose regular siding is just fastened to the sheathing with nails and that seems to do fine. However, Ipe is a different critter and I’m worried that too much movement in the Ipe could rip the screws out of the plywood.
Can anyone provide some direction on how I should handle this? Is it ok to rely on the plywood to fasten the Ipe to, or should I consider changing my approach? It would make this job many times easier if I didn’t have to worry about hitting the studs.
Thanks for any advice,
Matt
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Replies
Matt,
I’m not a builder, but I know from personal experience that Ipe is really heavy. I think you should screw into the studs with the longest screws you can drive. If you countersink and plug the screw holes, it should look fine.
Do you have access to interior side of the sheathing?Ie: are your walls open?
If so, add in extra studs where your planned Ipe screw locations are. Otherwise you probably should modify your screw points of the siding to engage a stud.
I'm not a mechanical engineer, and I haven't done what you're asking, but as you've stated, 1/2" ply for a heavy siding is worrying.
1/2" ply is insufficient on it's own to support the IPE boards.
The IPE should also NOT be fastened direct to the sheathing. You need a rainscreen.
Seal the plywood with something like Blueskin or another air barrier. At minimum seal at the butt joints, etc. Attach vertical battens to the sheathing at the stud locations to create a gap functioning as a rainscreen. Then attach more vertical battens to the plywood at locations at the end of the boards/ where the boards butt and all other fasteners points.
Then attach the IPE through the battens, through the sheathing to the studs, and at the ends, through the battens through the plywood. There will be some holding power at the ends where the IPE is attached only to battens and plywood, and the majority of the holding power should be where the IPE is supported by studs.
Thanks for the replies. Sounds like I should be aiming for the studs then. The sheathing has been waterproofed and I am installing over battens. It was just the placement of the battens and fasteners that I wasn't sure on. Also, walls are closed so adding additional studs is not really an option.
So, with the consensus that I need the studs to support the Ipe, what would be the minimum number of fastening points into a stud along the 10' long boards I should aim for to support the boards? Could I get away with fastening to two studs along each board - maybe about 1/3 of the way in from each end? Then fasten at each end and the middle of each board into only the sheathing? This install is a bit tricky as the studs aren't all at regular intervals so spacing out the fastening points might be a bit tricky. I might try to plug the holes but not sure if I want to take that on yet so I want to try to get the location points to line up as much as possible while still trying to make sure everything is secure and solid.
Thanks,
Matt
I am pretty much finished with my Ipe installation so thought I would upload some pics. I forgot how labor intensive Ipe is, but my wife and I feel that it looks great and really finishes off the house. In the picture with the windows I have 3 more boards to install at the bottom but I hit our foundation wall so I need to get a hammer drill and use concrete screws for those boards. The other wall was much more straight forward - we are going to place a hot tub against that wall so it will make a nice atmosphere for that. I plan on plugging all of the holes but want to give it a few weeks to make sure there isn’t any movement before installing the plugs. Anyone have advice on how to glue the plugs in but not make it too difficult to drill the plug out later to get at the screw if necessary? Seems that just gluing them in could funk up the head of the screw and make that very difficult. Is there something I could put in to create a barrier between the plug and screw head?
Thanks!
Matt
Not sure why those pics came out sideways, here are a few right side up.
No useful advice on the plugs, but it looks great.
Very nice job. The framers who built my Ipe-covered porches used yellow carpenter's glue to install the plugs. But I think most of the holding is being down by the pressure between the plug and the hole.
I realize it's too late now, but if you run strapping on the diagonal you can fasten it to the studs, have horizontal siding attach to it and have it act as a rain channel.