*
I’m building an arbor on my new house and want to laminate 3 or 4 redwood 2×10’s together to make a beam to span about 18ft. Would anyone have any suggestions on what kind of adhesive to use in order to prevent moisture penetration between the individual boards. Thanks for the help.
Discussion Forum
Discussion Forum
Up Next
Video Shorts
Featured Story
Listeners write in about haunted pipes and building-science tomes, and they ask questions about roof venting and roof leaks.
Featured Video
Highlights
"I have learned so much thanks to the searchable articles on the FHB website. I can confidently say that I expect to be a life-long subscriber." - M.K.
Replies
*
Issue 95 of FHB had some info on an exterior glued/laminated footbridge. Can't find the issue (dear, have you seen any old issues lying around?) but it had several methods discussed.
*Adam, thanks for your response. I pulled out FHB #95 and couldn't find the article on the laminated footbridge. I'll look a few issues in both directions. If you recall another issue number let me know. Many thanks. Ted
*b TVMDCGlue will help hold the boards together while the nails dry. To keep out moisture, run a bead of caulk along the top of each joint. Do not caulk the bottom joints so that any interior moisture can excape.
*ROFLOLHow long does it take for your nails to dry, Bill ??
*As soon as that interior moisture escapes?Sorry, Bill, laffing, too... Steve
*b TVMDCIt's good to see you guys aren't asleep out there! Takes about the same time for the nails to dry as to shoot the caulk with a stick nailer.
*Bill, I forgot to ask... What sort of connection do you make from the compressor's air hose to the glue bottle?(Also, happy to see that you're making use of TVMDC!... they do, of course!)Regards, Steve
*b TVMDCSteve, Actually I don't connect the airline to the glue bottle, I just squirt caulk into the feed tube of the Senco Nailer: when I pull the trigger, it waterproofs everything with one big splat!(Don't they, though!)Regards, Bill
*b TVMDCTed, All kidding aside, I believe what you are attempting is to double up multiple joists on their edge to carry the load for the span you want. That is not a glulam in which the boards are also face-glued but the face is up/down, not left right.It is a perfectly acceptable solution provided you follow a nailing schedule according to your local codes: perhaps (2 or 3) 16d at 24" centers, etc. Any good exterior adhesive will work and do caulk the top edge of the joints.However, why laminate joists together when a single beam could carry the load?
*Bill, thanks for the post. You're quite right I'm building up a beam rater than creating a glulam. The reasons I'm doing it this way is that the length (including cantiliever) is 23' and I have some beautiful water tank salvaged old growth redwood 2x10's in this length. To get a new redwood 4 or 6x10 in clear heart at this length would be astronomical. ted
*Bill, thanks for the post. You're quite right I'm building up a beam rather than creating a glulam. The reasons I'm doing it this way is that the length (including cantilever) is 23' and I have some beautiful water tank salvaged old growth redwood 2x10's in this length. To get a new redwood 4 or 6x10 in clear heart at this length would be astronomical. ted
*Ted,Found my issue, and it was there. By the later posts here, I see that perhaps we are talking about two different animals: the article was on curved laminations used for making a foot bridge, with the structure looking like a glulam. You are looking for a built up beam by the sounds of it. Good luck.Adam
*b TVMDCSounds really nice. Post a pic when its done. Good luck!
*Adam,My wife says (on her good days)"Honey how much will you pay me if I find it right where I said it was?" When I looked more carefully I found the article you referred me to and it did mention the glue that they used. Many thanks. When I looked up glue in the FHB index it made note of an article (issue 104 pg 108) on Gorilla Glue which is the product recommended to me by my local lumber supplier. This issue is one of six or so that is missing from my collection and wondered if you might let me know how they rate it, particularly for exterior use.thanks again, ted
*Ted, sorry for the joking around. I agree with Bill that you're got a nice project going, and hope to see the results. I've got to ask how you came by the generous lenghts of redwood? That stuff certainly would be hard to find in today's market.Good luck, Steve
*Steve,No apologies necessary. It's nice to see you guys and gals have so much fun while offering such a resevoir of expertise. Some years ago we (my two partners and I have had a contracting business in No. Cal. for 30 yrs-Christ that's a long time pounding nails!-as we've all wished "just a penny for each 16 pennies") bought a redwood water tank from the local water company (EBMUD) for $500. The tamk was 60' in diameter and 20' high with a roof, 20' long 3x8 staves, 3x12 doweled and splined flooring, 6x10 joist @ 16"o.c., and rough 6x12 sleepers @ 16" o.c. bedded in a drain rock base. The pad for the tank was some 40' below road level with no access for trucks or equipment. Unfortuneatly, the staves had quite a bit of rot starting at the water line, but the floor and paticularly the joist and sleepers were clear heart extremely tight grain redwood with many of the timbers having a select structural stamp on their ends; a grade that I didn't even know was used for redwood. These 6x10 joist and sleepers were variable lengths up to 26'. So between properly paying jobs we dismantled, and carried up a very long flight of stairs the roof sheating, roof structural beams, staves, and flooring. For the timbers we rigged a winch off the back of one of our trucks and dragged them up the slope. While the combination of the massive effort to get the wood out, the presence of rot, and the difficulty in getting the wood milled because the local mills were afraid that their blades and knives would run into imbedded nails, ets. made the whole project, as my partners like to point out, economically unsound, my heart rejoices everytime I see or use a piece of that beautiful and so very old redwood. It makes me envy or predecessors who routinely had the pleasure of working with clear, strait-grained woods from the old growth forests. Sorry for such a long winded answer to your simple question, but it made me recollect all those many stairs with a 20' long 3x8 on my shoulder.ted