Shed base: concrete or 2x6 deck + ground spikes?

[shabby]

I need to make a base for a shed out back, obviously concrete was first on my mind but for an 8x12 shed i'm going to need tons of concrete... literally. The second option that was suggested to me was to build a deck out of 2x6's and simply use ground spikes either https://www.rona.ca/en/short-heavy-duty-spike-48-steel-black-12665005 or https://www.rona.ca/en/adjustable-anchor-screw-50-pylex-steel-black-12665003
Using these spikes seems way easier than buying/transporting/mixing all that concrete, anyone built a shed using ground spikes to hold a shed base?

 

[Greenman]

The spikes look like a hit to me. The only 2 issues I see are keeping them aligned while driving them, and actually driving them into the ground. At 48" long, it's going to take some serious pounding to to drive them all the way in.

A poured pad would only take 63 60lb bags. Doable with a small electric mixer.

 

[mindless1]

Another option is set pressure treated 4x4s into holes in the ground, as corner posts. If it's not a dry climate it will increase the lifespan till rot to use wood treated for ground contact applications and put a foundation of pea gravel under it and around it to help water drain away.

 

[boomerang]

Obviously a concrete floor is a long term investment that could be worthwhile. That's a question only you can answer but I wonder have you priced out having the slab poured for you? It's a small project and it can be difficult to find people interested in doing small jobs like that I know, but if you have the skills to build a form then why not price out having the yardage of concrete delivered to you? You won't need much by way of finishing tools to screed it off and get a finish on it suitable for a shed. A friend and a 10' piece of straight lumber will do the job.

To run with what you propose as your other option, what do feel the ground spikes will accomplish? What value will they add to the project? I ask because you could accomplish what you desire by building a framework out of pressure treated lumber and putting it on cinder blocks. For that matter you could put it right on the dirt if you use lumber rated for ground contact. If you're building a shed out of wood, the entire project will be in need of replacement at about the same time.

I see the ground spikes as a false sense of doing the job the "right way" and the potential problem with either of them is the unknown of what is under the ground. Huge rocks, ledge, buried building materials, etc. Having said that I like the second ones you linked to and not the first.

Just some food for thought.

 

[Raizinman]

I put tool sheds at all my rental houses. I call a concrete company and they pour me a 10x10 slab. It runs about $1200. They do all the work digging, gravel, etc. When you get in good with your concrete guy, and tell them you are not in a hurry and will take left over 'end of run' concrete, it can be done a bit cheaper.

 

[crashtech]

The best shed I ever built was 2x6" on a cinder block foundation. It needed a step to enter, but it sure wouldn't ever rot, and was easy-peasy. The idiots that built my current house's shed did who knows what, but the 2x4s are sinking into the ground and the floor is rotting out from under the damn thing. What a pain it's going to be to correct.

 

[PowerEngineer]

I'm not sure how much weight those spikes are meant to handle without sinking deeper in the ground over time.

Actually that same site has really good descriptions of your various shed foundation options here:

https://www.rona.ca/en/projects/Garage-and-shed/Design-and-build-a-foundation-for-your-storage-shed
https://www.rona.ca/en/projects/Garage-and-shed/Design-and-build-a-foundation-for-your-storage-shed
The last shed I built used what they describe as the "On-Grade Foundation: Concrete blocks and timbers". This has held up well for many years, however the plywood flooring is getting a bit weak now (even though I thoroughly treated the sheets on both sides before installing).

IMHO an actual concrete floor is the best, most permanent option, however (as in my case) the city codes often consider outbuildings with concrete floors to be permanent structures and therefore subject to a whole bunch more rules (e.g. design review, setbacks, building permits, inspections, etc.).

Good luck whichever way you decide to go.

 

[herm0016]

I used the spikes for my chicken coop, they suck in Colorado rocky soil and go all over the place. I would not use them again.

 

[shabby]

@imported_Greenman who wants to move/mix 60 bags of concrete?

@boomerang i haven't priced out having the concrete poured yet but i'm sure it won't be cheap knowing what the locals charge. The ground spikes simply seems like an easy solution and perhaps it add's some stability compared to cinder blocks, plus you can fix any leveling issues simply by adjusting a nut.

@Raizinman i don't want to double my shed budget with having someone else pour the foundation

@PowerEngineer i've seen those screw type spikes being used for decks, but they use thicker 7' long ones rather than these smaller 4' ones, i wonder how i would screw them in though. I thought about cinder blocks but how high would this elevate the shed, with a deck floor it would seem i would need 2 steps to get in.
Thanks for the link, not sure how i missed that, i'm liking option 5 a bit more now than the spikes now.

https://www.youtube.com/watch?v=DVhA983CEMQ seems its easier than i thought to screw them in

 

[PowerEngineer]

@PowerEngineer i've seen those screw type spikes being used for decks, but they use thicker 7' long ones rather than these smaller 4' ones, i wonder how i would screw them in though. I thought about cinder blocks but how high would this elevate the shed, with a deck floor it would seem i would need 2 steps to get in.
Thanks for the link, not sure how i missed that, i'm liking option 5 a bit more now than the spikes now.

It's not a bad thing to have some space under the wood floor to allow for air circulation and keep the floor relatively dry. My tweak was to add mesh around the edges from the floor going under the gravel to form a critter barrier; do not want varmints taking up residence under the shed. Rather than steps, I built a pressure-treated wooden ramp which makes it much easier to get lawn mowers, wheel barrows, etc. in and out.

 

[Ajay]

What about concrete footers (in a sonotube) set to and appropriate depth for where ever you live? 1/2 dozen of those and your shed is not going anywhere. Sink some large bolts or some sort of ties into the concrete. Less to mix than a slab. Then build up the floor framing with PT (or a composite). I'd leave some room to breathe as mentioned.

 

[shabby]

That is one option i actually like, i just don't want to dig that many holes, took me 3 hours to dig two 4 foot holes for my deck, not fun at all.
The screw spike looks like it'll accomplish the same thing.

 

[Ajay]

That is one option i actually like, i just don't want to dig that many holes, took me 3 hours to dig two 4 foot holes for my deck, not fun at all.
The screw spike looks like it'll accomplish the same thing.

Whatever you prefer. I'd rent an auger - much much easier and not as hard on your back. You can even rent power augers, for no effort at all .
You can probably do it with 4, depends on the load and framing you use - I just haven't sat down and figured out what structure would be needed.

Edit: typo

 

[Mandres]

I'm planning a shed too, but it'll just be a simple pole-barn style structure. 8 holes with PT posts and some simple framing. I'll put down a layer of crushed concrete for the floor. Simple and cheap.

 

[Micrornd]

You know I really envy you guys, being able to just throw something up in the backyard
Here where I live in FL. we have all sorts of building codes that are enforced for things like this. And I live in a semi-rural area where any thing that could happen would only matter to me and mine

The structural integrity of the shed must be approved (unless it is OEM or built offsite and even then it must have the correct seals of approval).
All structures have to be anchored down (whether built onsite or off) and there is no discussion about how, that is clearly laid out by code (even any deck that is not ground level must be anchored or attached to footings)
And any and all county or city employees are obligated to report any non-permitted construction.

I built 2 smallish (8x8 and 8x16) 2' high decks at my place and had to get a retro-building-permit 3 yrs. later when tax assessor reassessed and turned me in and all building permits involving structures require a valid (as in no more than 5 yrs. old) land survey.

 

[ISAslot]

I used blocks and made a 'door-ramp'.

 

[Ajay]

I built 2 smallish (8x8 and 8x16) 2' high decks at my place and had to get a retro-building-permit 3 yrs. later when tax assessor reassessed and turned me in and all building permits involving structures require a valid (as in no more than 5 yrs. old) land survey.

Wow - a land survey! I'd love to put up a shed, but I live in the city now an have a small lot. I'd have to give up a parking space or too much of my small backyard (both bad for resale).
Permits are a must, they are easy to get, but the city takes a very dim view on building unpermitted structures (as in, tear it down, in some cases).

 

[Scarpozzi]

I just poured an 8X12 slab...The concrete bill was $345...including delivery. I had about $420 total including finishing materials to do the job (concrete boots, forms, trowels, etc...)

You can build a 2x6 deck and put the building on top of it. The ones you buy from the stores that get delivered are often decks that rest on top of horizontal 4x4 posts as skids. If you don't have to worry about moving the structure, you could start by digging 4 post holes and sinking treated 4x4 posts below the frost line....concrete or not....up to you. After that, buy your treated 2x6 lumber and use those to make a band around the outside of the posts near the ground....then add sheathing or some cheap exterior plywood siding to the outside of the building. For the roof, you just pick a point where you can build another 2x6 or 2x4 band around the 4x4 posts up top, saw the posts flush and add either some small pre-built trusses or build them yourself out of 2x4's and use metal mending plates.

I built one of these kinds of sheds a few years back and made it look like a barn....but ultimately didn't put the decked floor in (dirt floor) and built the bottom band at ground level with wire and flashing underground to keep animals out. I want to say, I had about $400 in mine after shingles and paint for an 8'X10'

 

[Jeff7]

I put tool sheds at all my rental houses. I call a concrete company and they pour me a 10x10 slab. It runs about $1200. They do all the work digging, gravel, etc. When you get in good with your concrete guy, and tell them you are not in a hurry and will take left over 'end of run' concrete, it can be done a bit cheaper.

Is that a direct pour from the truck, or do they use one of these, or does it affect the price much either way?

I've worked with concrete before, but it's always been bought by the bag and mixed by hand or in an electric mixer. I've never done anything that was truck-delivered.


I've also got a shed replacement sometime in the future. There's a slab present already, but it's close to a tree, and it looks like it's not very thick, possibly not even 4". I'm considering the route of ripping out the slab and sinking concrete-embedded posts into the ground as a base instead.
The shed that's there is fairly small, I'd guess 10x10ft. So far, that's a lot more than I need. So far.

 

[paperfist]

I just poured an 8X12 slab...The concrete bill was $345...including delivery. I had about $420 total including finishing materials to do the job (concrete boots, forms, trowels, etc...)

You can build a 2x6 deck and put the building on top of it. The ones you buy from the stores that get delivered are often decks that rest on top of horizontal 4x4 posts as skids. If you don't have to worry about moving the structure, you could start by digging 4 post holes and sinking treated 4x4 posts below the frost line....concrete or not....up to you. After that, buy your treated 2x6 lumber and use those to make a band around the outside of the posts near the ground....then add sheathing or some cheap exterior plywood siding to the outside of the building. For the roof, you just pick a point where you can build another 2x6 or 2x4 band around the 4x4 posts up top, saw the posts flush and add either some small pre-built trusses or build them yourself out of 2x4's and use metal mending plates.

I built one of these kinds of sheds a few years back and made it look like a barn....but ultimately didn't put the decked floor in (dirt floor) and built the bottom band at ground level with wire and flashing underground to keep animals out. I want to say, I had about $400 in mine after shingles and paint for an 8'X10'

Wow that sounds cheap, where do you live? 4 or 6" pad?

I want to build a 14x14 gazebo and was going to go the bag and mixer route. I thought concrete would be like $2k delivered.

 

[Scarpozzi]

Wow that sounds cheap, where do you live? 4 or 6" pad?

I want to build a 14x14 gazebo and was going to go the bag and mixer route. I thought concrete would be like $2k delivered.

Concrete here runs probably $110-120 a yard depending on what you have put in it. Go online and check a concrete calculator...it's not worth mixing that much by hand for a 14x14 pad. The lifting, mixing labor alone would take a man too long...even with an electric mixer. You'd end up with half of it cured before you mixed the other half.

I live in TN. I did a 5.5" pad...I was using 2x6's for forms.....but it probably evened out to a 4" after high spots in the gravel I laid down under it. I put plastic under the pad and used some wire for reinforcement that I had leftover from my garage pour. (I still have a bunch if you need any)

This last one, I finished it myself....not easy work, but you may have a friend that's done it before. I certainly could have used some extra help because I was tired pretty quickly trying to work it. You can learn how to screed concrete and probably even get some tips from the truck driver. If you worry about it being exposed to salt, make sure you get a 4000 mix and ask them to deliver it wet. It gives you more time to work it. All you really need is a good form, properly sloped, a long 2X4 to cross the form for screeding and an bull float.....rubber concrete boots too. ($20 from most home improvement stores). I ended up taking a 1x6 and cut it to about 24", sanded the edges....then took a 2x4 and ripped it longways to make a 2x2. I cut a 30 degree angle on the end of it with as much surface area as I could get and put screws through the top and bottom of the 1x6 to make a float with long 8+ foot handle...using lumber I had.

 

[twinrider1]

Around here a poured pad constitutes real property and will impact your tax bill. Go with something like a sled of pressure treated 4x4s and it is considered portable and doesn't add to the tax bill.

 

[Micrornd]

Around here a poured pad constitutes real property and will impact your tax bill. Go with something like a sled of pressure treated 4x4s and it is considered portable and doesn't add to the tax bill.

Here (in CFL) they are both real property, the difference being the sled foundation is required to be "tied down" with ground anchors, while the concrete slab (with required thickened edges) sits on top of the ground. Both can add (or subtract from) to the tax bill depending on quality and looks.

 

[twinrider1]

The older I get the more I want to move out in the country where I don't have to get permission to use my own property. j
Required thickened edges....smh...it's a shed, not a two-story home.

 

[crashtech]

I suppose it's prudent to have regulations in areas that are prone to extreme weather. Wouldn't want to kill a neighbor with an errant flying shed, after all. That said, most of that stuff is a barely disguised money grab.