Wrap & Strap - Max spacing between vertical nailers for 1" interior boards?

[bogart_bogesley]

Hi, I'm using the "wrap and strap" method for my structure--frame exposed on the interior and interior finish, insulation, exterior, etc etc "wrapped" around the outside of it.  I was looking the guides/posts pertaining to this technique and one thing that stuck out to me is that the wall cross sections for a lot of them specify 1" horizontal interior finish boards (T&G) nailed to the outside of the frame. (usually either hemlock or white pine).

My question is, what is the recommended maximum horizontal spacing for the vertical nailers which these 1" finish boards are fastened to?  I can see why some are using a 2" thick interior finish as 1" seems like it would be prone to bowing in or out.

My concern here is that since the frame is exposed on the interior I want to reduce crowding with vertical members as much as I can.

Thanks

[Brad_bb]

So I'm assuming this is on a timber frame? You are referring to the interior sheathing? I'm not sure the horizontal boards or nailers you are referring to.  Do you have any pics or a drawing to help make this clear?

[Ljohnsaw]

Are you referring to Girts?  In my frame (to be built next year), I have girts at the base and top of my windows.  That is 3' from the floor and 7' from the floor.  My posts are 12' (2' knee wall on second floor) so the "spacing" is 3', 4', 5' (IIRC).  My girts are 3x5 and 10' long.  The lower girts intersect the knee braces  I am using 1" T&G cedar boards.  My plans were engineered and approved by the county so I'm hoping I'm good :-\

[bogart_bogesley]

So I'm assuming this is on a timber frame? You are referring to the interior sheathing? I'm not sure the horizontal boards or nailers you are referring to.  Do you have any pics or a drawing to help make this clear?

Here's something I just threw together but not actually representative of my actual structure.  It is a picture of one wall section, the perspective being from the inside out.  You have two primary posts, a beam, two horizontal girts, one vertical "nailer", and then horizontal 1" T&G boards for the interior finish (pictured in blue).

Since with the wrap and strap method of contruction the frame is on the interior, there is no supporting structure to which the interior finish boards are fastened to other than the frame visible on the interior--in this case just the two primary posts and the one vertical nailer (let's say two 8x8s and a 4x4 respectively).

What I'm concerned about is maximizing the horizontal spacing between these vertical nailers so I can avoid the ugly appearance of having them closely spaced.  But I also want to avoid having the interior 1" T&G boards bow into or out of the structure due to insufficient support.  Here I just have one vertical nailer, but depending on the length of the 1" T&G and the total span between the posts, I would imagine I might need more vertical nailers.  So I just want to know the maximum horizontal spacing between these nailers that I can safely get away with.

Are you referring to Girts?  In my frame (to be built next year), I have girts at the base and top of my windows.  That is 3' from the floor and 7' from the floor.  My posts are 12' (2' knee wall on second floor) so the "spacing" is 3', 4', 5' (IIRC).  My girts are 3x5 and 10' long.  The lower girts intersect the knee braces  I am using 1" T&G cedar boards.  My plans were engineered and approved by the county so I'm hoping I'm good :-\

It sounds like you're using vertical 1" T&G boards given that you're talking about the spacing between your girts.  I'm talking about the same thing except "vertical nailers" instead of girts and horizontal T&G boards instead of vertical.  In fact, I'm considering reorienting my T&G vertically in order to avoid my issue/concern.

[Ljohnsaw]

It sounds like you're using vertical 1" T&G boards given that you're talking about the spacing between your girts.  I'm talking about the same thing except "vertical nailers" instead of girts and horizontal T&G boards instead of vertical.  In fact, I'm considering reorienting my T&G vertically in order to avoid my issue/concern.

Yes, vertical.  I was assuming you were talking vertical - my bad.  It allows me to use up "scraps" better.  I can make use of boards as short as 3'.  I can splice the boards at the girts and it will be invisible.

[Brad_bb]

So your sheathing (1" T&G boards) runs horizontally.  In a traditional barn for example, that would be the siding, which would run vertically.  Therefore you'd need horizontal girts spaced 3-4 feet apart.  I don't think I've seen it run as you have it.  My ceiling is 1" T&G run horizontal, but the common rafter spacing is about 2'-9".  Running vertical pieces in conjunction with girts definitely clutters up your wall space.  Horizontal girts are tradtional (barn).   I wanted more open walls so I build 2x6 framed walls on the outside of the frame  with a 3/4" spacer on the posts and beams to leave room for drywall or whatever wall covering you want.  Horizontal T&G would work well with a 2x framed wall with no girts or vertical nailers.  If Horizontal is really the look you want, consider a 2x framed wall.  It's the cost of the boards and your time.  If cost is your biggest driver, consider running the T&G vertically.

Additionally, Wrap and Strap typically uses the same nailers as the sheathing .  Here are a couple of past posts to study.  The first one by Rooster is a very good pictorial and description.
https://forestryforum.com/board/index.php/topic,54157.0.html
https://forestryforum.com/board/index.php/topic,57351.msg832804.html#msg832804
https://forestryforum.com/board/index.php/topic,74925.msg1135836.html#msg1135836