shed door, torsion box style

[cody michael]

YYes I was planning on using pocket holes to screw the 2x4 together

[Jebediah Eckert]

Why not just face screw them with the deck screws you have?

If you get too crazy with this thing you can no longer call it a "Shed".

[cody michael]

Why not just face screw them with the deck screws you have?

If you get too crazy with this thing you can no longer call it a "Shed".

It's not really a shed, it's my motorcycles new house/ over flow for my tools the wife says are cluttering up the garage.

I want to use the kreg jig because I'm laying the 2x4's flat, so to face screw I would have to go through the 3.5 inches of 2x4 and into the other 2x4, also not having screw holes on the outside will make painting/weather proofing easier.

I made the frame, I am going to go work on putting the skin on shortly, I used 2x4 for the sides, and spaces 5 2x4's through the middle, top and bottom, center where the plywood seam is, and in the center of the sheets of plywood, I don't want any warp...

[Jim Andrew]

Think I would put some plywood on the inside of the door as well as the outside.

[ian maybury]

A few thoughts Cody, coming in late.

If the door is exposed to heavy weather (especially driven rain, or run off from the building) then it's possibly best not to sheet both sides of it. Not unless you are certain that all of the joints will be 100% long term sealed. (I had a double skinned gate leak despite the joints all being sealed with silicone - luckily it's in iroko and hence highly rot resistant. Scary what it can get in through) It's not an absolute certainty it would get in (probably would be if it was a gate out in the weather, or if it was T&G board sheeted), but water can sometimes run down inside a double skinned structure and find itself with nowhere to go - and cause rotting especially along the lower edge. It only takes a very little if it's trapped inside the structure.

If you go to a single skin then it may rely more on the frame for support (but ply is good in this regard, so it may not be an issue), this is the traditional structure over here (the diagonals stop sagging): http://wiki.diyfaq.org.uk/index.php?...and_brace_door Lighter versions don't need the fancy joinery (tenons etc) provided the diagonals are placed so they run down to the hinge side and are tightly fitted.

It may not be necessary, and it might not be visually to taste - but if going double skinned as a second best (presuming sealing is not certain) it can pay to drill a horizontal line of say 1 in dia drainage/ventilation holes through the skin flush with the top edge of the lower batten. Also to make provision that the water can migrate down inside the door (and not e.g. pool over a higher batten) to this level. It's hard to keep timber dry, but with good ventilation it's slow to rot.

The ply obviously needs to be fully waterproof too (better if it was marine ply as the WBP varieties are not always trustworthy in this regard), and the edges well sealed.

It's very hard to beat a single skin door constructed as in the link from a rot resistant solid wood like iroko for longevity….

[Pat Barry]

For the design you are considering here I would use construction adhesive to laminate the 2x4's to the plywood. I don't feel those pocket screws are going to do much for you as structural / strength except make it easy to assemble the frame. For the plywood, make a rabbet in each piece to create an overlap joint and be sure to use the construction adhesive in this joint as well. Plywood is going to need some good primer and paint to weatherize it. It is likely to delaminate over time on the bottom edge due to water absorbtion and not drying completely and quickly after moisture exposure. I built some similar using Smartside brand sheet materials 10+ years ago and they are holding up great. I don't think plywood would have.

[Jim Dwight]

Your plan will work if you can find a way to hang it without it sagging. I would try to lighten it, however. 1/4 on both sides would make a stronger door than 1/2 plywood on one side. Rabbeting the 2X so you have solid wood at the edges will help avoid the sheet goods delaminating. Pocket screws are fine for joinery but use glue too. Construction adhesive if your joints are not so great. Titebond 3 would be fine is the joints are. Prime edges and both faces.