I can’t seem to bring myself to trust engineered lumber in all of its proclaimed glory.
How long does it really last. If I build a home with engineered wood joists, will the glue break down after 50 or maybe 80 years? Will the house have a lifespan due to the TJIs, LVLs and OSB?
I know that homes built of regular wooden components have survived for hundreds of years so far… I can’t see the same in engineered lumber homes.
The difference between stupidity and genius is that genius has its limits. -Albert Einstein
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Dooood! Stop scaring me. We're halfway through our SIP project (on a TJI deck, of course)
I have thought about that before, though. It is an interesting question.
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I was wondering the same thing today as I tried to figure a way to fix two trusees that are rotted at the heel where they sat on a plate behind a leaking fireplace. Discovered this when the brick came down fr the additions
I repaired a house that had TJI floor joist that all rotted out from very slight moisture problems in the crawl. I believe real wood may have not been that quick to rot
I am relieved that everyone seems to be on the same page as i do with this stuff... I was a bit nervous anticipating a chewing out on the subject... lol
When I build my own home, I am certain that it will be with traditional lumber.
The difference between stupidity and genius is that genius has its limits. -Albert Einstein
http://www.peteforgovernor.com
Well, I built with traditional lumber and regret it. The seasonal expansion and contraction of the 2x10 joists alone drives me batty. The kitchen cabinets move so much that in the winter, the coffee pot fits below the upper cabinets, and in the summer, it doesn't.
All that holds the cellulose fibers in wood together is a natural resin, lignin. The only real difference is that's a naturally occuring resin, and the stuff used in engineered lumber is man made. Andy
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Sorry about the last message, I meant to address it to "all"
I wonder if it is prudent to seal the TJIs after installation to prevent moisture problems. Maybe paint... maybe a parrafin type coating.
The difference between stupidity and genius is that genius has its limits. -Albert Einstein
http://www.peteforgovernor.com
It will suposedly last indefinitely if kept within the moisture and environmental limits.
Rot and other such things are obviously indicators of problems outside those limits.
It does have to be kept dry.
Cheers
More than that, I worry about remodeling some of these things we build. Massive clear spans, huge point loads.... you'd almost have to have a copy of the original plans or be able to gut it wide open in order to really figure out what the heck is going on inside some of these. And it's not just the framing either.... subfloor adhesive, tile backerboard set in thinset... all that type of stuff is gonna be a nightmare to take apart too someday.
I love good old 2x10's. I know what they can do and what they can't do. I know how, where, when, and why to cut them. I can do rudimentary jobsite engineering onsite and make confident educated decisions on working with it. And if I need a piece of hardware like a hanger or something.... there's probably 1/2 dozen of them floating around in the trailer already. I don't need to worry about web fillers, squash blocks, face mount of over the top hanger.... etc.
And with 2x10's.... I don't have to worry about the guy glueing 'em together on Friday around quittin' time. God don't have a quittin' time. ;)
--"tile backerboard set in thinset... all that type of stuff is gonna be a nightmare to take apart too someday."I just put 16 sheets of 4x4 tile backerboard in thinset this week...used over 3000 roofing nails as per product instructions (2" ctrs on perimeter 4" ctrs in field). Imagine tearing that out.
I thought the same thing laying it down on our 12' x 22' kitchen as well as the M/B shower, M/B floor, two other bathroom floors, and the laundry room floor. All over 3/4" T&G Advantec glued and ring nailed into LVL flanged I-joists. I'll sell the place before I try to tear this thing apart! That's just Pain.
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Interesting question, and one I've never seen seriously addressed.
But it doesn't really bother me. I haven't heard of plywood failing due to age, and it's basically an engineered product.
Someone mentioned remodelling. I think remodeling wil actually be a lot EASIER down the road. There are a lot less bearing walls for one thing. That certainly makes moving walls around less complicated.
Fewer posts + beams in the basement is also a good thing. How many threads have there been here about removing posts to open up a space?
I don't believe floors of houses built now will sag like floors of houses built 50+ years ago did.
Plywood is a fairly different animal than the other engineered lumbers I mentioned. Plywood is comprised of whole thin sheets glued together where the other products are chips and flakes glued together. I've see seriously delaminated plywood with a lot of stregth left just because the plys were still nailed through and therefore "assembled"... that's not going to happen with flakeboards.
The difference between stupidity and genius is that genius has its limits. -Albert Einstein
http://www.peteforgovernor.com
Remember in the sixties when laminated drywall was all the rage? Every house in the subdivision where my dad had his house built used it--first layer was nailed and then second only glued. My dad insisted upon plaster. In the eighties, all the houses up and down the street from my dad had their ceilings cave in (those next door that were built the same summer as his had theirs cave in within a couple weeks of one another). Dad was sort of gloating because his ceilings were still fine. I just hope glues have gotten better since then--but look at failures in finger jointed lumber--I've pulled the joints apart with my hands and that stuff isn't very old.
Houses built a hundred years ago had different lumber than the stuff that's available today.''Wise men talk because they have something to say; fools, because they have to say something.'' Plato
"Plywood is a fairly different animal than the other engineered lumbers I mentioned."
Not really - The same glues are used. Basically it's just wood glued together.
I don't really see anything to support your concerns.
If you're happy and you know it see a shrink.
I have seen furniture, built at around the time of the American revolution, made with veneers and glue, that still looks to be in good shape.
And those old pieces were made with hide glues.
Today's engineered lumber is made with adhesives different from hide glues, but that will probably hold up just as long.
Good point. In Lutherie hide glue is still chosen due to the fact that it is reversable with steam or warm water and vinegar.
I once had a repair job where some fool glued on a fretboard with what I assume was titebond 2...took me 3 hours to remove it in one pc. Not a fun way to spend time at the workbench.
Ok back to topic...my OSB was completly shot here under the shingles, but according to my guy next door, it was also not dried in properly for about 2 YEARS! Before I bought the house..that is pretty extreme, but I think like Pete, plywood may have faired better.
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I don't worry about the adhesives and trust them enough to use engineered lumber and floor trusses in my home. One of the characteristics engineers use when selecting an adhesive is lifespan in the field. The adhesives generally used in engineered lumber are phenolic resins. Phenolic resins don't creep under load and are totally waterproof. That's a main reason why they are used over, say, yellow carpenter's glue which does creep and will soften when wet. Phenolic resins have a very long history so their properties are well known. The first synthetic material ever made, Bakelite, is a phenolic material. Even samples made 90 years ago show no deterioration. You can go into an antique shop and see them today, just as strong as when they were new. With chemistry better known and controlled today I'm sure the current formulations are even more durable.
I opened up a 1st floor wall with a door in it recently to expand a 3 year old room addition. The floor system was TJI's with OSB T&G pre-Advantech, glued and nailed. The original addition contractor didn't flash the door or install a pan. A very small pinhole leak between the jamb and threshold destroyed 4 square feet of OSB and turned the last foot (the bearing point) of three TJI's into mush in 3 years. I love the flexibility, light weight, long straight pieces, etc. But the longevity is going to be an issue IMHO. I had to send pics and a sample to even get my lumber co. to even respond. That was three years, what's going to happen in 30. Another big concern is ACQ versus nails and fasteners. I was in the Bahamas recently where ACQ lumber is commonly used as framing members. The salt and ACQ's corrosiveness melted even Z-max framing connectors. I know these are extreme conditions but I feel it is only hastening the process. ACQ's ability to corrode fasteners is scary.
Just my .02
Scott
Well I built with it and I'm glad that I did. It allowed us to do what ever we wanted with walls. Not a load bearing wall in the place. After we put up the interior walls it only got stronger. As for how long it will last who knows? I won't care when we are 6' deep. It's one of the most strongest homes I've ever been in. Now I agree that if it is neglected with water intrusion or bad maintenance then it could be it's own worse enemy trying to repair it. Given that I manage high end property full time, that neglect won't happen under my ownership.
I can tell you one thing, I feel for the poor SOB who wants to remodel it. :-) Gypcrete, PL400, double layers of subfloor, glue nails, fully adhered finish floor (tile and wood) over RFH, FC siding, 100% ice and water covered roof, insul, insul, and more insul, home run everything, etc.. It will be easier to burn it down than take it apart.