# Thickness of plywood for bench seat which also stores books



## Capslock (May 25, 2010)

Hi there,










so the plan is to build a bench seat about 10ft long, 16" deep and 24" tall. 

The seat will be the top while underneith the seat will be a book shelf. Book shelves will be 2' long each, so a total of 5 sections.

How thick should the horizontal plywood be to properly hold the books and people. Consider 1 person that is 190 lbs, a lady which is less than that, and a baby on board all sitting on the bench at once for instance.

I have the impression 1/2" should be ok since there will be 1/2" ply vertically every 2' but I'd like to confirm with you all. I want this bench to last.

Oh, the bookshelves will be 1' high and if you are wondering where the extra 1' space is going to be below the bookshelves, this will be the foundation for the bookshelve and bench seat, 2x4s' every 2'. I have to put this part here because a baseboard radiator is on the wall I am building the seat and I need to keep the front free to allow the heat to dissipitate.

thank you.


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## mdntrdr (Dec 22, 2009)

I would use 3/4" ply on all. :yes:

1/2" will sag in 2' with any type of load.


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## jimmykx250 (Oct 12, 2009)

I agree. The cost difference from the 1/2" to the 3/4" is minimal in the big picture. Like you said you want it to last. :thumbsup:


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## minknency (Jun 8, 2010)

Measure the area the bench is to be placed. This will give you an idea of the size of the final bench. I would use 3/4" plywood. The 1/2" will deflect if someone sits on it.


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## Itchy Brother (Aug 22, 2008)

A suggestion,I would think about the 24" measurement.I measured a couple of chairs in the house and they came in around 17-18 ".If I sat in one that was 24" from floor to the seat my feet would be 5" off the floor.


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## cabinetman (Jul 5, 2007)

Itchy Brother said:


> A suggestion,I would think about the 24" measurement.I measured a couple of chairs in the house and they came in around 17-18 ".If I sat in one that was 24" from floor to the seat my feet would be 5" off the floor.



Nice catch Itch. Seating height for eating (dining height 29"-30") is about 18". A stool for an eating height like a counter top extension from a 36" high kitchen counter would be 24" high.


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## AlWood (Apr 18, 2010)

Caps, Itchy and Cabinetman got the point; 24" is too high for seating. I also agree with all the guys: no way of using 1/2"; use only 3/4". Even that is right at the edge with 24" support spacing and near 200 pounds load. With my bookshelves (and this is my main product:laughing, I usually go with up to 20" spacing (it is about the same as used for joist spacing under your floor), unless I am forced to go longer. You can make 6 sections instead of your 5; would be almost 20" spacing... 16' deepth is a bit too much for books; with most of the books it would make almost 2 stacks deep.... I am thinking of making the hight about 18", 9" horizontal spacing (plenty of book will fit into that; for the rest of them -- you can stock them up horizontally...), and 6 sections. My 2 cents...

A thought aside -- why keep them under the seat? In my place the books are a major decorative part of the space (everywhere, sigh), which makes a nice addition to their intellectual value:smile


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