[ptb]

Do (2)2x10x20’s sandwiched between 1/2“ strandboard have the same strength and span capability that a solid 4x10x20 does? Thx, Pete

 

[mark sr]

Not my area of expertise but it's always been my understanding that laminated beams are stronger than solid along with being less likely to warp or check.

 

[HandyAndyInNC]

This is a question for an structural engineer. All depends on the load it will have above it. With that length of span, you would be better off using trusses. I would never use a solid piece of lumber for a span that wide. The weight of the lumber itself will cause it to sag. Also, the engineer/architect will have the final word.

 

[ptb]

I failed to give further info on the use of the beam. It will be used for a patio cover supported by posts at each end and in the middle. So spam is actually less than 7’ to each post.

 

[Nealtw]

Depending on the load but a double 2x10 often will be enough to span 7 ft.

 

[3onthetree]

There's no reason to sandwich OSB between 2x's to achieve a load rating unless you have certain limiting obstacles, even then there are better ways. For a patio I assume exposed, you don't want to see that either.

 

[mark sr]

The OSB or plywood's main purpose is to bring the doubled up 2xs to the standard 3.5" width. A lot depends on whether or not the header will be covered.

 

[ptb]

Using the OSB as “filler”. beam will be faced out so moisture not an issue.

 

[3onthetree]

For a patio I assume exposed, you don't want to see that either.

Exposed meaning the beam to view, uncased, OSB = ugly

 

[Nealtw]

Using the OSB as “filler”. beam will be faced out so moisture not an issue.

We are never asked to add plywood or glues to a beam like that just the number of nails to be used to make them act as one. After inspectors and or engineers have approved the installation, they are often dressed out to be pretty and often look to be much larger that they are.

 

[HandyAndyInNC]

You made this sound like the span was 20 feet. The phrase of 2x10x20 made me think the span is 20 feet.

 

[ptb]

The beam will be roofed on the top and T&G on the bottom. The outside will have a fascia and gutter. Yes, my original post did make it seem that the beam would carry the entire 20’. I have used the OSB in making interior headers so the siding and/or Sheetrock doesn’t need to be shimmed , also in this case I want the Simpson brackets to fit and snug as possible

 

[Nealtw]

The beam will be roofed on the top and T&G on the bottom. The outside will have a fascia and gutter. Yes, my original post did make it seem that the beam would carry the entire 20’. I have used the OSB in making interior headers so the siding and/or Sheetrock doesn’t need to be shimmed , also in this case I want the Simpson brackets to fit and snug as possible

The hanger you use is the thickness of the steel and the number of nails holes. They come in 3" for the double and a variety of width for other uses.
Using a wider one as you suggest with something to fill it, is fine. :wink2:
In fact we often use a single and nail the second timber to the first, the number of nails is the same.

 

[ptb]

“... The hanger you use is the thickness of the steel and the number of nails holes“...

Not sure what you mean above

 

[Nealtw]

“... The hanger you use is the thickness of the steel and the number of nails holes“...

Not sure what you mean above

The hanger has to be rated for the load it will carry, they are not all equal in strength. The bigger the load, the thicker the steel is and the more nails needed.

 

[ptb]

Yes I understand that. Thx for the clarification. I will be using a post to beam bracket but I am sure the same applies to those

 

[House Designer]

Do (2)2x10x20’s sandwiched between 1/2“ strandboard have the same strength and span capability that a solid 4x10x20 does? Thx, Pete

No.
Assuming the same grade and species of lumber for each case, the (2) 2x10 has a net width of 3", because the 1/2" strandboard adds no structural strength.

The 4x10 has a net width of 3.5", so it wins in strength and span capability.

 

[ptb]

Interesting. Thank you!