My motorcycle collection seems to be growing, 4 right now and I've been looking, nee needing and wishing for a workshop shed in the garden to store/work on them all for ages. I've never done a shed, and I'm sure there are a few of you out there who have, my DIY skills are a bit rubbish to be hinest, but I can just about afford one now, currently the BSA is in a vac bag undercover, but working on all of them is a bit of a shocker without a work space.

I've found out that it's not cheap to build, but a 16x10 is the biggest I can get really (1k -1500 pounds) I've been quoted silly money to get the garden ready (1700 pounds) and shed foundations built and trying to get the costs down by doing it myself aswell as look at the various ways to build a base that won't move over time. I envisage that at least two motorcycles will be in it at anyone time, poss 3 and some of them are Heavy.

So advice on building the foundations would be very helpful;

Concrete slab - I've been told unless its 2ft thick, not to bother, it cracks, condensates for ages and not ideal. Cost I have no idea.

Plastic panels - a new thing, about 450 quid for the number I need, they say you can just set them on the ground, but I suspect that hardcore and then sand? http://www.taylorsgardenbuildings.co.uk/store/customer/product.php?productid=20122 is the best to do this, but wondering if they would move. This seems the best option for me on the face of it.

Paving slabs / Patio bricks - hardcore base, sand and then? could be costly but would look nicer..

So anyone that has built a shed foundation for motorcyceles I'd love to hear from you, sheds all seem to come with a wooden base, so I'd put chip board down on top to spread the weight out, as Id have a bike lift in there aswell.

email (option): kitharvey247@hotmail.com

I finally went for a concrete slab for mine and with a good hardcore layer the whole thing is only about 6 inches deep, so 2 ft seems a little excessive. Perhaps if you are looking to trade up to a Sherman sometime in the future, 2ft would be good, but for everyday use with motorcycles, my 6 inches has served me very well (no smutty comments please!) The slab is 16ft x 12ft and with me supplying the hardcore and doing the digging out myself, it cost me £500 about 6 years ago. Perhaps not cheap? but no cracks, no condensation, no problems.

Do a raft like this:
Dig the area to a level 9" below the finished height, in there you want 4 inches of hardcore (broken bricks/concrete, big stones) fill the gaps with smaller hardcore & make sure its all rammed down. (ram it down so its an inch or so lower around the edge so the concrete above it is a bit thicker near the edges of the slab).
Then cover the entire area with sand & brush it in the gaps & holes, keep putting sand down until nothing sharp protrudes & the top half inch is only sand.
Lay a DPM (cheap plastic damp proof membranes are found at Screwfix etc).
Now you need a steel reinforcing mesh which is available at builders merchants or steel stockholders normally a wire grid with 4" holes & is a DIY equivalent of what they use under motorways, its very important as it holds the slab together but most important is if its positioned correctly it turns your floor into a giant lintel.

The critical position of the mesh is 1" up off the DPM sheet. so put 1" spacers under it ( not wood or absorbent material, or anything sharp) polystyrene packing works well but use just a small piece here & there just to hold the mesh up while you pour concrete.
Now pour your concrete slab making sure it goes through & under the mesh, it will be 4" thick & 5" at the edges. the weight of a bike on the top is counteracted by the mesh not being able to stretch ( concrete lintels work like that).
Finally, something alot of people forget & that's after you pour the floor it needs curing with thin polythene to stop it drying out & after a week take off the polythene & keep the slab wet for a week.
If you just let concrete dry quickly without curing it you weaken it alot.
leave it at least 2weeks after pouring before walking about on it.
I've done a version of that system except with 8" of concrete & that happily held a 7 ton vehicle & hasn't cracked in over 10 years use.

Both of my (block built) workshops have a slab for the floor area, obviously in this case contained by the blockwork walls. I used quarry waste (bits of broken stone) as filler which I purchased from a local quarry very cheap..Then the sand, damp proof membrane and the concrete on top. Depth wise about 6" of concrete on top of the 'base' if I recall correctly. I didn't use any reinforcing at all....20 years later I've had no problems with it You will need to use scaffold planks or similar as shuttering to contain the poured concrete while it goes off. Make sure you knock in some decent supports for these as there is a reasonable amount of weight (or outward pressure) involved....You will need to paint or cover the finished floor though as it never stops shedding dust. I did mine with paint and then the cheapest vinyl flooring I could find....That makes it easy to clear up oil spills but I cut some (generously sized)chequer plate pieces to go under the stands and prevent damage to the flooring...Probably this year I will renew the vinyl as it has got damaged here and there over the 20 years since it was fitted..I shouldn't worry about your DIY skills...it's really just a matter of getting the concrete mix strength correct and taking your time with each stage to get it right..I asked a couple of friends who were more into this stuff for a few tips and then got on with it....Ian

email (option): ian@wright52.plus.com

All I did for my own shed was lay some paving slabs down. OK it isn't a huge shed and only holds the one bike and a load of shelves etc for spares and tools and so on, so there is a fair bit of weight there. Working to a tiny budget I did it with a fair bit of labour preparation and the minimum £'s outlay. I reckon you should make the base at least a foot larger all the way round than the eventual shed. I flattened the area, which happened to be soil, removing the softer top soil until I got to the harder stonier subsoil. Levelled it, checking with a plank edge and a spirit level. Installed a bed of sharp sand and rammed it hard and levelled that as well. The final layer was an unrammed dry mix of sharp sand and cement, again checked carefully for being level with a long straight edge and spirit level. The paving slabs were laid on this as you might do for a patio etc and checked for level, being tapped down with a suitable lump of wood to get them finally adjusted and bedded. Then you either wait for it to rain or water it gently with a watering can with fine rose on it. Dont slosh it with the hose pipe or you will likely wash the sand/cement mix away :-)Give it plenty of time to set before you order the shed. Mine has been there for over ten years now and shows no signs of movement. It may be that your land/soil is particularly soft or soggy and might require a deeper foundation digging and some hardcore in. But it would be worth investigating this first as most prefabricated sheds are integral units once assembled and just 'sit' on the base, and as long as the ground is not subject to 'movement' dont really need an 'over-engineered' base to sit on.

email (option): cruiserchooser@hotmail.co.uk

Hi Kit,the sizes you are talking about,it may be worth your while keeping an eye on ebay for a concrete sectional garage.these turn up now and again where people have finished with them and for not a lot of dollar.
i bought one for a hundred quid and one for a hundred and ten.you normally will have to take it down yourself,and will need a couple of strong lads to help.
you can put the side door where you want,you can put a pitched roof on it ,and you can make it secure .wait till you find one nearby,and while you are looking,you can prepare your base.
cheers rick

email (option): richardholt@rocketmail.com

kit,
the best way forward now is to use a fibre reinforced concrete, in the 35 newton range. this means no steel to drop in, and is an easy pour.
if you ask your concrete supplier, they should have it readily available, and most will supply a fact sheet to help.
if you cant, let me know and i'll e mail you one.
atb

email (option): chris.astinbarker@btinternet.com

Put a concrete base down as stated but just one thing if your wooden garage dont get a concrete one you will never stop condensation . Make your base 15ft 10 by 9ft 10 for a 16 by 10 garage.It stops water getting between the garage and the concrete slab .the price is about bang on.At a later date you can insulate it with plywood and lagging.

email (option): cooperbaumber@yahoo.com

Hi kit.
You don't say where you are located but if you are in the UK then wood does not need to cost that much.

I deal with a lumber yard in Gisburn, called railside timber, he only really deals with job lots rather than bits, but if you sketch out your requirements you will get the wood for about a quarter of the standard retail prices.

It makes building a workshop a real possibility on a tight budget.

They are an old fashioned lumber yard, bit like the waltons, but the prices are unbelievable and the quality first rate.

For the building just think heavy duty shed frame and go on from there.

Good luck.
Darren

email (option): dwrudd@lineone.net

'Keep it up high and will surely stay dry' don't build it in a hole. Dig out top soil ( there will be a BIG heap ) , spread and compact the hardcore, crushed concrete is about £5 a ton, up to ground level then shutter and pour concrete on top. Six inch thick unreinforced will stand tractors in a yard, so four inch should do bikes. Just a thought for the shed look up timber dungwall it's 8x2 inch tounge and groove treated timber needs minimal framing, is warm, fairly secure and look OK. Unlike a friend who put up a very secure shed using Steel RSJ uprights with concrete railway sleepers slotted in between! I think it would stand shell fire! His previous shed was broken into by smashing a hole through the six inch concrete block wall!!!

sorry for the ramble

Cheeers Pat

A typical house slab in Australia is 4" thick, there is an edge beam typically 12" wide and 18" on the perimeter of the slab. There is trench mesh in the beams. 3 bars wide and slab mesh in the 4" section. As already stated raise the mesh off the damp proofing ( black PVC plastic). You can buy plastic chairs for this and the trench mesh.

Depending on the size of the slab and any load points you may need internal beams in the 4" section.
Depending on you soil type, is it sand or clay will depend on the beam size etc. if sand scrap away any organic matter ie grass under the slab and lay 2" of washed sand ( no clay in it).
It best to build on a raised surface ie hill and build it up on sand.
When laying the PVC damp course duct tape any joins and leave it wide enough to wrap up and over the top of your slab under the external walls otherwise water will enter the slab.
I still have water issues here in Australia even though I only get 16" of rain a year.

Also the reinforcing mesh should be keep 2" away from the edge of the slab otherwise it will rust and give you concrete cancer.
Keep the slab moist for a week in order to minimize cracking as concrete take approximately 48 days to cure. You can build on it in less than a week though.

email (option): Darrenacartwright@yahoo.au

2 feet thick!!!!!!!!!!!! Whoever told you that owned stock in the cement business. I build for a living, we re- bar the floor in a 16" grid and tie it, double the re bar on the edges, lay the bar grid on bricks and pour 6 inches of concrete. Once dry we cut two expansion joints in it. Thats for a car garage, a lot more weight than bikes. The key is to prepare what's underneath and reinforce the concrete,re bar in a tight grid is best, I've had better luck with it than the 4" hardware mesh. I'll only pour on EXTREMELY well compacted ground with a layer of crushed stone. Take from it what you want and maybe they do it differently over there, but 2 feet seems like nuclear blast proofing!

Did mine with rebar and concrete to a depth of just over the top of my wellies . Let it cure and topped off with OSB boards which insulates a bit and keeps the feet from freezing to the floor in winter.
The man delivering the premixed concrete had a load on board which wasn’t what I had ordered but the fiber reinforced stuff meant for a massive motorway bridge. Apparently this will mean calling the air force for a bomb strike if I ever want to remove it.

Cheers
Pete

The cheapest & easiest thing to do is get one of those steel prefab sheds that you put together with pop rivets or self tapping screws.
Now for the base, level an area aabout 1 foot bigger in each directon than the shed.
Lay drive way pavers over the leveled soil.
You can usually get these for free from people who want to extend or demolish their house.
Sprinkle cement dust over the pavers then sweep them so that the powder goes down the cracks.
Sprinkle lightly with water , this will set the concrete.
leave it for a week.
Erect your shed on top of the pavers.
Get some "hoop iron " ( the steeel strip that you use over old pailing fences, ) and slip it under the shed from one side to the other and fix it to the outside of the channels at the bottom of the walls.
Do it both front back & left right.
Now get some sheeets of old core flute. It is that double wall plastic that signs are printed on. It is also used as protecting pannels on top of pallets so you can get it for free from sign shops or transport depots.
Fit the core flute neatly inside the shed, wall to wall.
Lay some thick builders plastic on top of this and glue the joints to make it water tight.
Now lay a second layer of pavers over the top of this and cut them to be a tight fit.
The weight of the pavers plus every thing on top of them , will hold down the shed.
The core flute will insulate it from underneath and the builders plastic means that any water will go under your top layer of pavers so your floor will be dry .
You can then get some styrene foam sheets , again for free from transport depots where they unpack shipping containers and some more core flute.
Cut the foam to fit in between the rails on the shed walls then glue the core flute over the foam.
If you go for a gable roof shed you can cut some 2 x 4 's to span the shed & sit on the walls so you can store long things overhead and have some wood to mount lights to . Stop them about 2' from the door.
Again you can oft get these for free as demolition waste from internal wall frames.
I use long arm desk lamps ( pick up from council clean ups ) clamped upside down from the roof rafters for lighting as you can direct the light where you want it.

Bike Beesa
Trevor ( the cheap )

email (option): wariron@tpg.com.au

My mate built his shed walls from pallets which he covered with stirling board and then painted...it worked Ok even though it seemed a bit 'Heath Robinson'...I tend to build so that it will last longer than I will...that way I don't have to do it again...Ian

email (option): ian@wright52.plus.com

Just as a point of interest, I was once involved with a survey on a Medieval Church. We needed to find out how deep the foundations were as there was mining proposed in the area and they wanted to know if it would impact on the church. The foundations for this particular Medieval stone Church were a little over 18 inches deep in places and there was no concrete, hard-core, steel bars, fibre mix or any of this sort of stuff involved. It was a little deeper around the spire at just over three feet, but still just a trench dug into the soil and the church built on top. It had been there for over 600 years and had no cracks or subsidence damage. I also did a survey on a warehouse right next to the river in Gainsborough and it was built straight onto the surface, no foundations at all! I'm not suggesting you do this or that everyone else here is wrong, just thought it was interesting the way things used to be done compared to today. Were they doing a slap dash job or are we going overboard?

Thanks everyone for your advice, I've read alot and thought hang on, best ask the guys I know who do the things I need a workshop to do. Yeah 2ft is rather accessive. Well I've got some great ideas and process/steps now to follow, no idea it took that long to cure but not in a hurry, just need it soon ish, quite interesting over 200 views on this topic. Thanks again, I'll save the thread and get planning.

Lincoln
You are right, engineers here in Australia apply a rule of 200% in order to cover their asses.
I am a Carpenter and joiner and teach it as well, and the standards are over the top. I have renovated many 19 century buildings that have had bricks laid directly on beach sand and to cracks in the brickwork. However many newer homes have serious defects mainly due to inferior products, workmanship etc but it is a lot to do with clients wanting a Brough for the price of a Bantam.
Darren

email (option): Darrenacartwright@yahoo.au

Kit,

2ft is the adviced thickness of a foundation for a wall (of a shed). Perhaps this causes the confusion.

Regards,

Sven

email (option): snvosselman@gmail.com