Best construction adhesive, wood to wood

[abunaitoo]

There are so many out there.
So many reviews and clips.
So which is the strongest????
I'm looking for something to hold the surface of plywood to wood beam.
Looking to repair a sagging beam by sandwiching it between 3/4" plywood.
Sistering????

 

[havasu]

Personally, I like Liquid Nails, but Gorilla Glue is a close second, except I hate the oozing action of Gorilla Glue when it begins to harden.

 

[Steve123]

I like PL Premium.
But just about any of the construction adhesives will give you a joint stronger than the wood it is fixed to.
If you really want to study this to death, check out what Todd found.

Project Farm Part 1
Project Farm Part 2

But not sure plywood is going to give much stiffness. I more commonly see sistering done with another 2x

 

[tomtheelder2020]

But not sure plywood is going to give much stiffness.

The stiffness of an I-beam is determined by the height of its web, not its thickness - doesn't matter if that I beam is wood or steel. The existing beam plus thickness of the plywood make up the flange of the I-beam that resists lateral deflection.

 

[tomtheelder2020]

Looking to repair a sagging beam by sandwiching it between 3/4" plywood.

If you jack the existing beam back into place before sistering, it will still sag some when you remove the jack support. Jacking a bit beyond original position will reduce that effect.

 

[RedneckGrump]

I love PL Premium... But PL comes in so many different types, From styrofoam to brick and etc... I think the PL is the number one to use... Just my preference...

 

[Steve123]

I love PL Premium... But PL comes in so many different types, From styrofoam to brick and etc... I think the PL is the number one to use... Just my preference...

The standard one, which will say "3X stronger".
The "8X stronger", I think they just put fillers in it, so the cured compound is itself likely stronger, but the bond to the wood is already stronger than the wood, and with all the fillers in it, the "8x" stuff is extremely difficult to squeeze out --- will bend your caulking gun, and give your hand a big workout.

 

[Eddie_T]

For laminating a beam I would choose a good wood glue. Some glues are designed for hanging rather than joining and might be prone to creep. I think I used Weldbond when I made my 16' beam for a garage door header.

 

[abunaitoo]

Going to jack it higher than even before adding the ply.
I'm sure it will sag a little.
It's been over 25 year since done, and it has sagged over an inch.
Took out the sag with a pole, but the pole is always in the way.
So it has to go.
Friend who's going to help said not to spread the PL out.
Just run a bead and nail gun it.
Seems that if you spread it out, it dries to fast, and will not bond as it should.
Working on removing the trim and sanding as much of the paint as possible.