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Garden Shed Framing Question- 2x4 vs 2x3

Model A Fan

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I'm doing an 8'x10' garden shed in my back yard. I was looking at ways to reduce the cost of the shed and saw that 2x3s are roughly $0.50 per board cheaper than 2x4s. For such a small size, will I run into any issues with rigidity or strength? I'm planning on two or so windows and perhaps two doors, maybe one. I'm not certain yet.

Am I OK to use OSB for the flooring?

Also, when it comes to siding, can I just use ceder bevel siding? I found a source for 1x8" cedar siding for $0.55/lineal foot and $0.75/lineal foot for 1x10". Which would be better to go with? What would my siding overlap need to be for this type of siding? I like the horizontal pattern more than vertical like board and batten.

Thanks!
 
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K'ledgeBldr

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I don't see a problem with 2X3's for that-
OSB "subfloor" is fine- it's actually better than ply.

Were you planning to side directly to the studs? If so, you'll need to diagonally brace the corners- let-in bracing is pretty cheap- or you can just use 2X3's on the interior. Otherwise, sheath the whole bldg with OSB.

That siding might seem relatively inexpensive, but have you considered the ANNUAL maintenance that comes with it? I'd be doing Hardi in a heartbeat along with PVC trim.
 
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Model A Fan

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I don't see a problem with 2X3's for that-
OSB "subfloor" is fine- it's actually better than ply.

Were you planning to side directly to the studs? If so, you'll need to diagonally brace the corners- let-in bracing is pretty cheap- or you can just use 2X3's on the interior. Otherwise, sheath the whole bldg with OSB.

That siding might seem relatively inexpensive, but have you considered the ANNUAL maintenance that comes with it? I'd be doing Hardi in a heartbeat along with PVC trim.

I was planning on painting it to match my house and garage :headscrat. Would it still need a lot of maintenance? As for the OSB, I think I will use that then. I have two sheets already and one sheet of ply I rescued from the dump. All nice and dry :D

As for Hardi Plank and PVC, isn't it much more expensive? :confused:

EDIT: I just found Hardie Plank on Home Depot for roughly $0.66/lineal foot. I might go with that instead.

How are you referring to diagonally bracing the corners?

I calculated that from the original 8x10 (80 square feet) if I use 2x4 construction, I end up with 69.87 square feet in the end. If I use 2x3 framing, I end up with 73.9 square feet. Giving me roughly 4 square feet more by using 2x3 construction. Is it worth the extra space to use the 2x3s? :confused: :headscrat

:D:rocker:
 

B_Bimmer

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2×4's will vastly increase the structural integrity of your building. You could probably get away with 2×3's with a good building plan, but given the quality of wood available today I wouldn't think it worth the hassle. I would NOT do OSB for the subfloor. OSB does not like moisture that builds up under unconditioned spaces, it'll do fine for a while but eventually the edges will explode into a mess of bloated woodchips. Treated or not that is the fate of OSB. If you've got an exceptionally well drained yard or plan to move within a few years give it a try. I don't, I prefer to build something once and not have to think about it again.
 

Showkey

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OSB and any thing close to the ground where moisure is present will create a huge problem:

Blow.jpg


116440d1406905256-wet-osb-problem-zzzzzzzzzzzzzzzzzzzzz.jpg
 
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theoldwizard1

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OSB and any thing close to the ground where moisure is present will create a huge problem ...

True !

A coat of oil based primer and a top coat of latex or oil based paint on the bottom after you have nailed the OSB to the floor joist will help a lot. Joist should be pressure treated.

Removing the sod and organic material and back filling with gravel and then placing the base 6-12" up (lots of light and ventilation) will help even more !
 

ItsNemo

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You're talking about what $15-20 to use 2x4's instead? Why wouldn't you?
 
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Model A Fan

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Look up the Shed of Doom. That will give you a step by step on how to build a shed.

Uhh, I can't see the pics at work but based on the description it sounds like it is quite the shed. The comments make me wish I could see it! :D

True !

A coat of oil based primer and a top coat of latex or oil based paint on the bottom after you have nailed the OSB to the floor joist will help a lot. Joist should be pressure treated.

Removing the sod and organic material and back filling with gravel and then placing the base 6-12" up (lots of light and ventilation) will help even more !

I'll spring for some plywood and save the hassle. I rent from my parents, so I want to build something that will last a while. I'd rather leave them with a good shed for future tenants or for themselves if they decide to move into the house in order to sell it later.

I do not have pressure treated joists...is there something I can coat the joists in that will extend their lifespan?

OSB and any thing close to the ground where moisure is present will create a huge problem:

Blow.jpg


116440d1406905256-wet-osb-problem-zzzzzzzzzzzzzzzzzzzzz.jpg

Well noted. Why do home builders use it for the subfloor and wall sheathing?

2×4's will vastly increase the structural integrity of your building. You could probably get away with 2×3's with a good building plan, but given the quality of wood available today I wouldn't think it worth the hassle. I would NOT do OSB for the subfloor. OSB does not like moisture that builds up under unconditioned spaces, it'll do fine for a while but eventually the edges will explode into a mess of bloated woodchips. Treated or not that is the fate of OSB. If you've got an exceptionally well drained yard or plan to move within a few years give it a try. I don't, I prefer to build something once and not have to think about it again.

I think I will go with 2x4s. I don't want it to fall over.

You're talking about what $15-20 to use 2x4's instead? Why wouldn't you?

Fair enough, I don't want to cheap out.
 

Showkey

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Well noted. Why do home builders use it for the subfloor and wall sheathing?
.

Because it's cheap.......and will be OK if it stays completely dry....but......in shed floor it would be impossible to keep it dry, especially from the ground up even with paint, gravel and some distance the gound moisure will be present.

Mold%20on%20OSB%20Sheathing.jpg
 

The Cobbler

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2x3 on that size shed is no problem, even on 24" centers, but I wouldn't use OSB floors.
A shed I built at a campsite the ex & I had I used 4x6 pt on edge for footing and built the shed with 2x3. concrete patio stones for the floor between the the PT. 20 years later it is still standing, the only thing changed is the new owners have sided it because the OSB was looking ratty. I imagine the PT footing is showing signs of deterioration at ground level too. OSB floor would be long gone.

A good buddy just put up a shed kit from Cosco, what a pc of junk for the money IMO. It is all 2x3 including floors ( not PT) , gable walls are framed 4' O/C with a few horizontal laterals to stiffen the osb. He has at max a 10 yr shed if he's lucky ( IMO)
 
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D45

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If its just a gardening shed, and you want to save money, then 2x3s will be fine

However, if you take a 2x3x8 and a 2x4x8 side by side and step on it, you'll quickly see the price and quality difference

However, once again, if its a light duty shed........then use 2x3s

Just depends on how long you want it to last for and how dry/wet of an area you are building it in

For me, I went with 2x4s and PT (double layered) flooring..........cause I need and wanted it to get strong, and last
 

grommit

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Do not use 2x3,s. It's a dementially unstable size. Will warp, bow and twist a LOT. All accessories window, doors etc are made for 2x4 construction. So 2x4 is the answer. 8ft and precuts are(usually) pine. Pick and reserve the straitest for doors, windows etc. Buy 12 foot lumber for wall plates. It's hem/fir rather than pine. Same price per board foot as 2x4 but better lumber. If you can use pressure treated deck boards for the floor. It is a shed right? A cheap skylight is a real nice addition. Good luck should be a fun project.
LHH
 
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Model A Fan

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If its just a gardening shed, and you want to save money, then 2x3s will be fine

However, if you take a 2x3x8 and a 2x4x8 side by side and step on it, you'll quickly see the price and quality difference

However, once again, if its a light duty shed........then use 2x3s

Just depends on how long you want it to last for and how dry/wet of an area you are building it in

For me, I went with 2x4s and PT (double layered) flooring..........cause I need and wanted it to get strong, and last

I'd assume that because it is in the wall, the 2x3 would still be relatively rigid. I will do a guesstimate on how much lumber I'll need and see what the price difference is. I liked the fact I'd get an extra 4 sq ft out of it :lol:.

As for the siding, Hardie Planks seem pretty good. They would match the house, but the cedar would match the garage... What kind of "extra" maintenance would I be doing on the cedar siding if I paint it that I wouldn't be doing on Hardie Plank?
 

Firebrick43

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I will say use 2x4's as around here I have never seen a straight 2x3.

also skip the osb on the floor. Ok on the wall but do install a rain screen especially since you are in the pacific north west. very easy. apply roofing felt horizontally working from the bottom up over lapping it(top over bottom). apply a 1/4 to 1/2 furring strip of some type of ripped knot free wood where you studs are. place a 6" wide piece of roofing felt over these furring strip and nail your siding on. this allows air behind the siding to dry it out. Especially important with painted wood but even the hardiplank it helps. you wont keep paint on wood if you don't, it just peels. Dont use house wrap, they are finding it doesn't work as advertised.

Hardiplank is much superior to wood in my opinion. a pain to work with but durable. I use a utility knife to score both sides and snap it for dust free cutting. nail with maze ceder splitless siding nails in the center but still have to drill the corners or you will split them when there is no stud in the corner and nailing to osb i drill larger and use a ring shank aluminum roofing nail as the very thin siding nails wont hold well in the osb like they will studs. Use quad caulk to caulk corner trim and ends. Find the little clips to help hang it, they work well.
 
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Model A Fan

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If I opt for going with cedar siding, what kind of maintenance would I need to do if it is painted that I won't have to do if I go with Hardie Plank? I like the look of the cedar boards, but it may be a waste if I paint them. If I don't paint them, what kind of maintenance would I be looking at?
 

rburke65

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For a savings of 50¢ a stud how much money are you saving.....$16....... No way would I used 2"x3"s. And no also on the OSB
 

Firebrick43

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Cedar is a **** shoot any more. If it's all old growth it's awesome. Not much of it is anymore. Areas can rot out. If you implement a rain screen, prime both sides and paint it may be pretty trouble free, but hardieplank is as long as you don't leave it set in a stack and get rained on and then paint without letting it dry. Really don't see much natural cedar so I can't answer that.
 

millnk

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I recently built a shed based on some models of garden sheds I saw online. Always build a weather resistant frame. When building the frame use a 2X6 pressure treated lumber. Many prefab sheds use untreated construction grade lumber for the floor frame, this is fine only if the shed is indoors. Even if your shed is under ideal conditions the floor will always be exposed to some sort of moisture and in time the untreated lumber will rot. For the floor deck use a ¾ inch exterior grade plywood, anything thinner than that will flex between the joists.
 

MushCreek

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I'd be curious to see how a quality OSB subfloor like Advantech would hold up. My house floor was exposed to the weather for months with no issue, and it got rained and snowed on a lot. FWIW, I used 3/4" pressure treated for the floor of my shed.

I used 2X4's so I could put lots of little shelves in between the studs. It's a great place for paints and yard chemicals to slowly go bad.
 

bczygan

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For a small temporary shed, 2x3's will work. I have a 3x17 with the walls and roof framed with 2x3's. 12/12 roof pitch with a good overhang keeps water off the sides.

Structurally sound for a decade or more.

I do consider it a temporary shed though. It is supported on a few concrete blocks, set on the ground.

Bill
 

theoldwizard1

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OSB and any thing close to the ground where moisture is present will create a huge problem:

Which is why what is UNDER the floor is so important ! Plus, most suburban neighborhoods have "critter" (skunks, opossums, raccoons) that like to burrow under a structure place right of the ground.

You want your floor to be high enough off the ground that plenty of air and LIGHT get underneath.

Your floor joist and beams should pressure treated. The best flooring is 5/4 PT deck boards. The are solid, will hold a lot and will not rot.
 
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Voi

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I'll spring for some plywood and save the hassle.

One of the siding companies now makes a cement board subfloor material for sheds. I've never seen it or priced it. It is supposed to be as water resistant as pressure treated plywood but more resistant to rodents.

I've also heard good things about the 500 day no sand guarantee subfloor material from Georgia Pacific. I think it's priced around $28 a sheet locally. I do not know how that compares to PT plywood. It looks like a really dense OSB.
 
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