Shed support spacing?

[Gooserider]

I have decided to try and de-cruft some of our living areas and the garage by building a metal shed, 10' x 14' nominal size, to use mostly for cruft storage, possibly for occasional minor workshop stuff.

In order to floor the shed, I will be building a foundation platform out of 2x6 pressure-treat, and 5/8" plywood. I'm trying to do it moderately on the "quick and dirty" side, so rather than doing the full digging down below the frost line and putting in poured supports, I'm going to be putting down a few 4x8x16" cement blocks on the ground that I will level as needed to make a foundation. The ground is fairly level and solid, so I expect this will hold up for a reasonable length of time, and also help keep me from having to worry excessively about dealing with the code enforcement types since it will only be a "temporary" structure... :coolsmirk:

The question I have is what sort of spacing I should use on my cement blocks? As I mentioned, I'm using 2x6's for the joists under the floor, running across the 10' dimension on 16" centers, and attaching to the 14' end boards with joist hangers. Some of the folks I've been talking to have been saying every two feet, which seems rather excessive. While I want the floor to be sturdy, the more support points I have, the harder it will be to get everything level, so there is a balance...

Gooserider

 

[lobsta1]

Goose,
Lowell may have a max 120 square foot requirement & then a permit will be needed. Instead of cinder blocks, I would use the spexial pyramid shaped blocks. They have a wider base & narrower top. That helps to minimize frost heaving. With 2x6's a 4' or 5' spacing would be plenty.
Al

 

[Gooserider]

Thanks, Lobsta - I'm not actually in Lowell, rather I'm in a community just south of it that people who don't live near can neither pronounce properly nor spell :lol: so I keep it simple by referring to the nearest largish city... I will probably go with your suggestion on the spacing, but I already have the cement blocks, so those will be what I use...Might split them in 1/2 though, especially the ones in the center...

Gooserider

 

[TMonter]

Goose, I can post pictures of my 8x12 shed that's almost complete it you like. I did side stringers of 2x10x12' and cross supports at 2' intervals of 2x6x8'. It's all stick built, completely assembled with screws other than roofing and is turning out to only be 1/16" out of square which rocks.

My Shed Pictures

 

[webbie]

We used to put gravel in the holes below the cement blocks in order to help them drain...that was further south, though. We've set 40,000 lbs on 6 blocks (food storage units).

I would think that one on each corner and one at the 1/2 way point (7 feet) would do the job. If you want to really overbuild it, add one more, that would be one about every 3.5 feet on the 14 ft length. If you can place them where they hit BOTH the 14 foot end band and also one of the joists sit on them, so much the better.

 

[TMonter]

I did the gravel in the hole bit and tamped it down with a hand tamper to prevent settling. So far it's worked really well.

 

[Gooserider]

Well I want to minimize digging - after all this is New England, where our primary crop is rocks... Digging holes tends to be a real pain as rocks are every where >:-( and make you have to dig bigger and deeper than you wanted to just about every time... My plan at this point is to find the low point, level a block or two on it, and dig the others down as needed to match...

This shed is not stick built, it is a basic metal "shed in a box" from Home Despot - Arrow Brand model DK1014A, which was a definite good buy - I shopped pretty extensively, and all the pre-fab wood sheds in that genera size were thousands of dollars, and most of the other 10x14 sheds were close to a grand. This one was $499, and looked comparable to the more expensive models (most of which were also from Arrow) With all the added material, mostly the wood for the floor and some patio blocks, the cost came up to ~$750. Based on my experience purchasing the materials for my wood shed, I don't think I could have done a comparable stick built shed for under a grand, and I wanted something that I didn't need to put a lot of time and energy into building. I would have gone for another portable garage, but I wanted something a little more weather tight, which this should give me.

I will be building the floor out of 2x6's, using 2 14' lengths for the sides of the frame and 9 12' lengths for the cross members (actually I want to end up with a platform 121" wide by 160.25" deep per the manual) - I will be putting the cross members on 16" centers, and using steel joist hangers to tie everything together, with probably some deck screws for insurance.

From what its sounding, I need to have three supports on the 14' sides of the structure - one at each corner, and one in the center. I'm not sure about the 10' cross members - do I need to run a row of supports down the center of the 10 span to suport those crossmembers? Or possibly do something like just catching every other joist or something like that? Or is 10' a safe unsupported span for a 2x6? (If it matters the door is in the center of one of the 10' sides)

Gooserider

 

[d.n.f.]

Can't you throw in some of those floating concrete pilons? They are four sided sloping things with a t or a slot on top that you lay a joist across. Used in deck building. Dig a smallish hole and fill with gravel tamped and put it level on top. Joist lays across allowing for larger spans.

I have seen people put sheds on top of them with one in each corner.

 

[Gooserider]

Can't you throw in some of those floating concrete pilons? They are four sided sloping things with a t or a slot on top that you lay a joist across. Used in deck building. Dig a smallish hole and fill with gravel tamped and put it level on top. Joist lays across allowing for larger spans.

I have seen people put sheds on top of them with one in each corner.

Probably could, but I've already purchased the cement blocks (8"x16"x4") so I figure I might as well use them instead of going out to get more stuff...

Gooserider

 

[Hogwildz]

If you have the blocks already, it wouldn't hurt to set one under the middle of the structure floor. Heck if ya havem, why not 3 rows of 3, a row at each outside wall, then a row down the middle. Extra support is never a bad thing. especially if you will be storing heavy objects inside.

 

[Gooserider]

If you have the blocks already, it wouldn't hurt to set one under the middle of the structure floor. Heck if ya havem, why not 3 rows of 3, a row at each outside wall, then a row down the middle. Extra support is never a bad thing. especially if you will be storing heavy objects inside.

I think that's more or less what I'm going to end up doing - I've been laying out the blocks today, along with doing some tree trimming to get rid of the dead branches that might fall on the shed, raking the first couple layers of crud out of the way, etc. Looks like it will work pretty well if I put three blocks lengthwise down each 14' side, and then run a row of about 4-5 blocks down the center, putting each 16" long block on an angle so that it will catch two of the ten foot log 16" O.C. joists about in the center.

Gooserider

 

[iceman]

Thanks, Lobsta - I'm not actually in Lowell, rather I'm in a community just south of it that people who don't live near can neither pronounce properly nor spell :lol: so I keep it simple by referring to the nearest largish city... I will probably go with your suggestion on the spacing, but I already have the cement blocks, so those will be what I use...Might split them in 1/2 though, especially the ones in the center...

Gooserider

try me goose what town near lowell has a funny name....at first i thought ipswich...but i not sure thts close to you...then haverhill but thats north of you ...hmmmmmm

 

[Gooserider]

Thanks, Lobsta - I'm not actually in Lowell, rather I'm in a community just south of it that people who don't live near can neither pronounce properly nor spell :lol: so I keep it simple by referring to the nearest largish city... I will probably go with your suggestion on the spacing, but I already have the cement blocks, so those will be what I use...Might split them in 1/2 though, especially the ones in the center...

Gooserider

try me goose what town near lowell has a funny name....at first i thought ipswich...but i not sure thts close to you...then haverhill but thats north of you ...hmmmmmm

Nope, it's not that the name is funny, it's more that it isn't pronounced like it's spelled by the natives, and if you give the name to a telephone sales person, you almost always have to spell it... It also violates the standard "Boston accent" rule, in that you do pronounce the "R" (but skip some of the adjacent letters)

Gooserider

 

[lobsta1]

Carlisle

 

[Gooserider]

Carlisle

Close, but that one is pronounced the way it's spelled pretty much...
Gooserider

 

[myzamboni]

Worcester (prounounced Wooster)?

 

[Gooserider]

Worcester (prounounced Wooster)?

Nope, way to far west... Think Route 3, between 128 & 495

Gooserider

 

[lobsta1]

So how did the shed raising go?
Al

 

[Gooserider]

So how did the shed raising go?
Al

It is now up... Took a bit longer than the instructions said, but otherwise no major problems. Just got back from the disaster that was an LP convention, so I haven't had a chance to put anything in it yet, but should be able to start doing that this week...

Definitely you need at least a couple of people for much of the assembly, there were parts where you needed to put nuts / screws together on opposite sides of panels that were more than an arm length appart, but nothing to difficult otherwise.

I ended up using a cement block stack on each corner, plus one in the center of each 14' side, a full block stack in the center of the 10' span that the door fell on, and 1/2 block stacks in the center of the other 10' spans - each stack I burried at least one block below the surface, then added enough additional depth to make the platform level.

The platform itself was pressure treated 2x6's tied together with Simpson galvanized ties and nails per the Simpson specs, plus 3" Deckmate screws...

Gooserider

 

[myzamboni]

Worcester (prounounced Wooster)?

Nope, way to far west... Think Route 3, between 128 & 495

Gooserider

got it.

 

[lobsta1]

Goose,
Thanks for the info on the multi-person effort required for assembly.
Al