Parallam Plus Psl By Weyerhaeuser

[rasorinc]

I am considering using these wall 2x4s and 2x6s all nominal and UNTREATED in my build. I have not verified waterproof adhesive yet or it's compatability
with epoxy. These I've used in commercial construction and they are stronger than Glu-Lams. Might be hard to bend but my build does not have much of that. I priced out a 2 x 4 x 10' at $8.25 per which is 6.66 BF or about $1.20 a BF. Big site with many charts re: strength, fiber bending, spans, etc.
Would appreciate any input you have re: these or other similar parall grain manufactured lumber. Looking to use them for frames, keel, stringers, etc. Moved to Tenessee and not much hard of softwood choices here.
Thanks much, Stan. http://www.ilevel.com/exterior/e_Par...L_treated.aspx

[gonzo]

You can use them with no problem in some cases. However, it is not possible to answer your question without knowing what the design is.

[TollyWally]

As a carpenter I might stress caution. There is a difference between suitability in the lab and in the field. Long term exposure to moisture is never a good thing with these manufactered products. They just don't seem to shrink back to the same state during the dry half of a wet dry cycle.


I know what is claimed but I've been disappointed more times than impressed in the field. I've never seen a gluelam come apart in the weather. I think the strandboard beams are better suited for achieving long clearspans rather than a substitute for good tight grain lumber. I'd lean towards plywood based composites rather than strandboard if I was forced to choose. I think they'd fare better with the wet/dry cycles. You sound experienced, what's your impression?

[rasorinc]

When I could no longer get large beautiful beams or ran into very heavy snow loads I started using GluLams. When an 6 x 16 glu lam was called for in the plans I noticed it would only leave 6'-3" head room in the garage which was illegal so I contacted an engineer who calc.out a paralam of 4.5" x 12" which could handle the same loads. Ive used many of both over the years (untreated) and many carried to the outside of the building exposed to moisture but not direct rain or snow. No wood holds up to that W/O a cap.
Have had zero problems in their usage over 35 years. That just started me thinking of using paralams-all vertical grain, good exterior adhesive and stronger then GluLams and totally dry with uniform deminsions. All the wood in my build will have 3 coats of epoxy encapsulating it. I'll buy a 10' piece cut it up to some 3/4" wide and 1" wide and put some scarf joints in it and let cure and see how it bends. Maybe attach some vertical pieces and hit them with a sludge to see if the joint or the wood gives first. I will post my findings. Thanks all for the input. Stan PS I will never use OSB board on a boat.................................................

[TollyWally]

LOL'
I'm sure you wouldn't use osb! I just think of those parralam beams as being more closely related to osb rather than plywood. I don't know what you're building but perhaps you might ponder the possibilities of making glued up laminated beams of plywood. It's been done on the west coast for plywood hulled charter/patrol boats etc. up to 40' or so for a couple of generations.

[Joe Petrich]

We use very large (40'L x 3'H x 6-8"T) laminated beams overlaid with FRP for engine girders in the boats we build. They work very well.

[TollyWally]

Well there you go! It's nice to let the other guy do the experiments.

[Boston]

glue lams or micro lams is generally the direction I tend to go

the company that provides wafer board ( beaver puke ) around here has been fined millions for producing substandard materials
multiple times so I'd be cautious using any engineered lumber
my advice to Horton is

boil that dust speck
boil that dust speck

is what Im thinking

if Whoville survives then soak it and dry it about a hundred times and then see how it holds up

I gotta go with Wally on this one as I also do not believe the manufacturers claims on this kind of stuff
call me paranoid but Ive seen to many odd ball failures

cheers
B