Board and Batten Nailing Techniques
Board and batten siding details for good performance. May 16, 2008
Question
I'm installing B & B siding on a 24 foot high building using 1" x 10" x 12' boards. I'm wondering what to do where the butt ends meet? Should I install a small horizontal batten to hide the joint? I'm using green white pine and I'm not sure how much shrinkage will take place over the length of the boards. Also, how will this look with these short horizontal battens across the wall? Should I stagger them up and down to break up the visual line?
Forum Responses
(Sawing and Drying Forum)
From contributor A:
If I understand you correctly you are running your 12' boards vertical. If so, from my experience I would not put a horizontal strip across because it will collect moisture from the rain, snow and will not last long. I would only butt the boards and consider some type of attractive seam sealer and/or flashing. You still may want to seal the boards afterwards or use a large overhang with guttering to protect against moisture.
From contributor B:
I used a 45 degree miter as opposed to a butt joint and buttered it with caulk before joining the pieces. It was a PITA but I feel I have a joint that is very water resistant.
From the original questioner:
To contributor A: Thanks for your response. What is your experience with the amount of shrinkage over the length of the boards?
From contributor A:
Cut a 45 degree miter on the ends that meet, use a lot of caulk, but do not put a board horizontally across the joint. The boards may shrink a bit in length, but such shrinkage will be negligible.
From the original questioner:
Thanks. Any particular type of calking you would recommend?
Here is another question. I saw another post somewhere advising to put the bark side of the board against the building. Wouldn't the board cup the wrong way? Boards cup in the direction of the curve of the annual rings, right? That would mean bark side away from the building, wouldn't it?
From contributor D:
Vulkem 116
From contributor C:Boards want to flatten out the curve of the growth rings. Bark side against the building sounds correct.
From contributor E:Boards cup toward the bark. Fasteners on the boards should favor a center position to reduce splitting from shrinkage, i.e not on the very edge. Battens should be fastened to only one board or between the boards in the crack.
There is a commercial galvanized flashing used for plywood sheeting that might work for you on the horizontal joint. An added benefit is no moss or algae growth below the flashing. I believe there is a shrinkage calculator on this web site with the other calculators. It's available from the main page.
From Professor Gene Wengert, technical advisor, Sawing and Drying Forum:The shrinkage calculator does not do lengthwise shrinkage as it is so very small in most cases. The nailing procedure is very important, as noted above. I prefer that the batten nails do not touch either "board."
From contributor A:Thought I would add a little something we use on batten. We use the screws that are brown in color and are made for cedar and pine to put the batten on. They can be purchased in the orange and blue box stores. It is slower but you can really pull the batten down tight and the screws will not back out like nails. We also have used them to put the boards on, especially poplar where they will split more often than pine. If you do get a board that splits too much just unscrew the batten and replace the board without making the mess with a crowbar prying the nails out.
From contributor G:Why not lap the end of the top over the bottom a couple of inches and run a horizontal at the top under the eaves?
From contributor H:The traditional means for installing board and batten siding on barns is to overlap top to bottom by ~1'. Furring strips are added to the top purlins so the boards remain parallel to the wall. This is a proven method that does not lead to unique moisture problems. Since your boards are not long enough, contributor G's suggestion would work. The horizontal board would be protected by the eave. Shrinkage in length is minimal and has no effect.
Here's a link that shows B&B nailing patterns.
Board and batten nailing patterns
From contributor I:One other method for nailing green boards is to nail only along one side of the board, in a position where the nail will be hidden by the batten. This provides for hidden nails, yet allows the board to "float" under the batten as it shrinks, thus avoiding splitting. If you install siding this way, it is critical to use either spiral or ring shank nails for your battens, in order to keep the siding tight.
