Planning a shed build

[Nihil]

Hello all,

I'm planning on building a 12x16 shed to use for storage and for blacksmithing.  This size keeps me under the size needed for building permits in my town.

I was planning to have a crushed stone floor as I'd rather not have a slab poured.  I'd level the area prior to building with 3/4" gravel (approx 4 inches), then build a 12x16 perimeter of 4x6 pressure treated beams on top of the gravel, building walls, etc. on the beams.  I'm thinking tying the perimeter foundation together with at least 6 2x4's between the 4x6's would be good and would still let me bring in crushed stone for the floor.

Any initial thoughts on this idea?

 

[ThomasPowers]

So the "foundation" is just 4"x6" laying on gravel?    What is your soil like?  Will there be issues with water infiltration?  Sharing Storage with a smithy seems like a bad idea unless the stuff being stored is not flammable!  Certainly not things like a snow blower or lawn mower containing gasoline.

[Nihil]

Hence why I was thinking of the need to include 2x4's to connect the 4x6's on the long sides of the walls.  With 4 inches of gravel underneath what would be a 4" crushed stone floor, I felt that water infiltration will be limited.  The area for the shed currently drains well and doesn't have standing water after storms.

I could put in some foundation screws to add extra strength to the foundation.

I was planning on using one end of the shed (4') for storage, mostly seasonal stuff (outdoor Christmas stuff primarily), not things with gasoline in them.

[Glenn]

You may want to put drains below the crushed stone to remove any water that may accumulate.  Do not forget that it can drain both ways, out and in.  Be sure the outlet of the drain is well below the level of the crushed stone.

 Now would be the time to add a conduit for any future utilities.  Only cost would be the conduit itself at this point.  

You may wish to put a goesinta in place now for use later.  They come in handy for many things.

[Nihil]

Goesinta?

[George N. M.]

Blacksmith dialect for "goes in to."  Usually, a receptacle of some sort that something "goes in to."

"By hammer and hand all arts do stand."

[Daswulf]

Think verticaly Buried square tubing. Like in the 2" or a little bigger range. You can make different tool bases "go into" it. Its a sturdy mount point. 

You can also remove the tool for the extra space. 

[Frazer]

Could you dig post holes in all 4 corners of the shed below the frost line and pour concrete footers for you to bolt the sill to? In the grand scheme of things it wouldn't cost much and it seems more permanent to me.

[Irondragon Forge ClayWorks]

Another way would be to set a border foundation with concrete blocks and j-bolts cemented in with the sill bolted and off the ground.

[Goods]

Here’s the “Goesinta” grid in my new shop before the slab was poured.

 

2’ - 2 1/2” square tube with 1/4” walls spaced 2’ welded to the slab rebar. Intended to hold 2” square tube stands. (Building new stands for my post vises is high on my list…)

David

[Michael]

I'd consider either concrete footers under the corners to tie the whole thing to the ground. Not wanting deal with cement I can understand. Setting up my own crushed stone shed, 8x16 in a corner of the yard, I buried pier blocks to tie the posts to.  Under the piers is a 12 inch deep trench with drain pipe and gravel.  I'm at the bottom of a hill with dense clay soil so drainage was necessary. 

[Merlin05]

In some parts of the country, I'm considered an expert or SME on shed design and build.  Ask me anything you want, I'll be glad to help!

[onetreeforge]

Working on gravel or crushed concrete is horrible, just have dirt, its way better

[NickyJ]

I don't mean to hijack this year old thread, but... rather than start a new one for almost the same scenario in need of advise, I figured I'd ask here.

I'm also in Massachusetts and planning on building a shed, also under 200 sq ft.  I have a coal forge and plan on making a side draft hood with a 12" flue straight up through the ceiling.  I want a dirt floor but New England winters bring frost.  I plan on installing concrete footers/sonotubes for 4, maybe 6 points all 4' deep (below the frost line).  I also plan on insulating the walls.

My question is, how could I reduce the risk and damage from frost heaves inside the shed?  I am specifically concerned with frost heaves lifting the coal forge thereby damaging my side draft hood &/or chimney.

I'm hoping to start hammering this out in the next few weeks but time is running out since winter is coming so any suggestions are appreciated.

Thanks in advance!

[Irondragon Forge ClayWorks]

Welcome from the Ozark mountains. Here in the Ozarks the frost line is much shallower than in MA, but when we built our 24X30 garage with a mono pour concrete floor and footings, the contractor put 2 inch Styrofoam insulation against the inside of the footings down to below the frost line (20in I think) to prevent frost heave. Don't know if that will work in your case though.

[Goods]

If you worried about frost heaving the forge and damaging your hood, don’t mount the hood to the forge. I my stack is supported by heavy wall brackets and I suspended the hood from that with all-thread. 
https://www.iforgeiron.com/topic/67236-new-shop-build/?do=findComment&comment=742158

Keep it fun,

David

[George N. M.]

Welcome aboard from 7500' in SE Wyoming.  Glad to have you.

Since frost heave is, as I understand it, a function of the water in the soil freezing and expanding anything to minimize soil moisture will minimize frost heave.  So, diverting any drainage in the area, either surface drainage or the water rumming off the roof of the shed or any nearby buildings will help.  Also, not building adjacent to any lawn or garden watering area will help.  if you have a choice of sites the highest and most well drained will have the fewest frost heave problems.

Finally, setting your footers below the frost line will keep them stable.  Check with local plumbers to see how deep they lay water lines in your area.  The local building code may have a provision that water lines must be laid X inches or feet deep which would safely be below the frost line.

"By hammer and hand all arts do stand."

[Frosty]

Welcome aboard, glad to have you. Does the ground heave much when it starts to warm up in spring? As George says frost heaves are a sign of FS (Frost Susceptible) soils. 

If you're casting your piles in sonotubes wrap the outside in a couple layers of plastic before you set the tubes, and lift them a few inches off the bottom of the hole. The plastic will let the soil slip over the pile without gripping it and the wider "button" at the bottom will act as an anchor so it can't move.

Keeping the shop floor from moving is as easy as digging below organic overburden, (red clayey soil near the surface) and filling with coarse gravel to within about 6" of the finished grade and finishing the floor in compacted D1 gravel. As you fill the floor do it in lifts of about 6" and compact it hard before adding the next lift. A plate compacter works nicely and can be rented for reasonable.

Do NOT WET the ground to compact it, just dampen it as you rake it level. A LITTLE moisture acts as a lubricant allowing denser compaction too much water displaces fines as you compact and leaves voids as it dries meaning it's less dense (hard).

Allow for drainage away from the shop as George suggests, keeping water away is much easier than dealing with it. Build the grade under the shop above ground level if you have to, 4" is a good start but don't get silly about it. 

Tell me what kind of soil you're building on and I can be a little more specific. I worked for the state of Alaska DOT and PF materials geology section for 20 years. Sure I was a driller but structure foundations is what we surveyed soils for.

Frosty The Lucky.