Yet another Shed/Summer house thread

Yes I know we have loads and every ones is extremely useful but I have a few specific questions about my build and wanted to tap into the the incredible collective knowledge on here, plus we all love a shed thread 🙂

Mine will be 5m wide and 4m deep with some shed adjoining as a home to all the usual gardening stuff, mower etc which I dont want in my “Summer house”!

Just cleared the last of the pre-shed build jobs including fence replacement all around so old shed removal begins this weekend and ground prep for the concrete to arrive Saturday the 13th.

First question: I estimate 2 cubic metres of concrete on top of sharp sand and some crushed stone, around 200mm deep in total. I have a large number of small paving blocks from a job lot I got ages ago. Can they be used on top of the sand instead of buying crushed stone (which will save me buying stone and getting rid of the blocks) and the 100mm of concrete poured directly over??

Normally the ‘crushed stone’ goes first, then a bit of sand then some DPM. The sand is to stop the stone piercing the DPM. The stone needs to be well compacted and ideally mot type 1 but for a shed base anything will do, including old paving slabs and blocks but you do need some fines in there to fill the voids. You’ll need to break them up as much as possible so there aren’t voids underneath, too. I’d put anything big down first, go at it with a sledge hammer, then put the mot over that, then whacker plate it down. Sand, dpm, concrete.

Thanks Nick thats exactly what I needed to know. If I lay the blocks (I will break them up first so they are much smaller) cover with sand and Visqueen then the concrete on top??

Thanks again!

Ideally break them up in situ so you get as much of the small bits in there too. I suspect you’ll still need some mot to fill the gaps but its cheap.

This is more or less what I did:

Brilliant, thanks

Why not put the paving blocks on top ???

I can’t see them fully replacing the aggregate/crushed stone from a structural POV unless you broke them up.(as the concrete won’t fill into the gaps)… though they’d probably be fine … what weight do you expect the shed to exert?

Unless your soil is full of roots (or otherwise unsuitable) 200mm is perhaps overkill? Many people would even just stick a bit of sand and then put down paving blocks…. so a very layer of sand then some crushed stone and then 50mm of concrete is a huge upgrade over “just paving slabs”

I like stuff to last and my shed was more like the above…. and the concrete dries faster so you can start the shed…

I’d also recommend checking out the EPDM roofs…. if you like stuff to last. It’s a bit more expensive but better in every other way to any type of felt (My shed came with felt but I just didn’t use it and stuck the EPDM on)

This is more or less what I did

You could probably build a machine shop on top of that 😀
That’s about what the cheapskate that did the foundations fort our garage did.

You could probably build a machine shop on top of that

Funny you should say that 🙂

Our little shed is on slabs, on sand, on a little bit of mot and that is absolutely fine. Just wanted a bit more for the big one.

what weight do you expect the shed to exert?

Not sure yet but likely its going to fulfil a few uses. It will be insulated and have a wood burner for all year round use. I dont think it will contain anything heavy at all so I think parts of it will be over engineered!!! but I want to follow this process anyway which gives me scope later.

I’ll follow your picture Nick but with my broken blocks instead of MOT.

Our little shed is on slabs, on sand, on a little bit of mot and that is absolutely fine. Just wanted a bit more for the big one.

I have no direct access to the back garden that doesn’t involve carrying by hand… after over-engineering the foundation I really cursed myself when it came to carrying bags of aggregate/sand and then mixing!

Not sure yet but likely its going to fulfil a few uses. It will be insulated and have a wood burner for all year round use. I dont think it will contain anything heavy at all so I think parts of it will be over engineered!!! but I want to follow this process anyway which gives me scope later.

Seriously check out the EPDM roofs if you want “over engineered and built to last”

It’s a design decision I haven’t regretted .. (My experience being sheds seem to mainly rot when you don’t keep up with re-felting… )

Updated Pic, been busy with Work but had a couple of weekends to get some work done. 3m of concrete instead of the 2 I had estimated!!!

Excuse the mess in the pic but since then I have installed 6 of the 14 6X2 beams and I will be putting the board on the roof on Saturday and wrapping the walls in membrane. Question is what thickness Ply for the roof, will 12mm be enough??
[/url]20170622_205517 by mcivord[/url], on Flickr[/img]

I’d put 18mm on personally. You putting joists in at 400 centre’s I take it?

Cheers Wrightyson, yes 400mm centres.

Not a good picture.
[/url]20170626_200402 by mcivord[/url], on Flickr[/img]

Looks good. Just a thought…. if it’s being built from primarily wood ie: combustable material, is it within 1m of the curtailage of the property? Rings a bell with me if a permitted development IIRC.

Just looking at a similar sized project myself and that’s looking great.
Did you make the doors? If not where did you get them?
Did you need planning permission?
Cheers

Height is 2.5m at the highest point which is above the doors. Around 2m at the fence end which is about .5 of a metre gap all around. No planning as its within permitted development, the shed I took out was the same height!

A friend gave me the doors they are damaged hence the donor door on the grass to the right for me to cut bits out of. Had some faff replacing the hanging brackets etc but working now. Downside is they only open from the inside so I have to build a door to the left. The left hand side is a thin shed with a door anyway but now I have to make another into the summer house!

Looks good. Just a thought…. if it’s being built from primarily wood ie: combustable material, is it within 1m of the curtailage of the property? Rings a bell with me if a permitted development IIRC.

That’s a building regs issue rather than planning. If it is within 1m of a boundary and bigger than 15m2 floor area then it needs building regs sign off if it is made of combustible material. Its 30m2 max before it needs sign off if its non combustible

As for the roof, you’ll probably get away with 12mm but 18mm would be better. OSB should be a little cheaper.

Nick have there been any amendments to that reg regarding boundary and combustibles? Quite a few done in April last year and hoping that may have been one of the tweaked ones or I might have some issues.

I’ve not seen any changes to that but I haven’t been keeping a close eye on it. It’s still on the planning website. https://www.planningportal.co.uk/info/200130/common_projects/43/outbuildings/2

I have heard of people playing a bit loose with the definition of non combustible but only anecdotally

Well anything a bit woody is going to struggle with even the slackest building inspector. I’ve got a good relationship with all the local guys and a couple of indys but if anybody reports it I could end up wasting ££££

Finish the joists today and overhang then ply. Anyone know a good place for Cedar cladding?

[/url]20170701_172905 by mcivord[/url], on Flickr[/img]

Have you looked at Marley Cedral cladding?

Thanks Sharkbait, I’ll take a look!

Mrs Surfer has just reminded me that as its in a corner we will only see about 2sqm of it anyway!!

With the Cedral pricing the best I could find online was 18/plank but going to a building supplies place (like Travis Perkins) I was quoted £13/plank.
Watch the cost of the trim profiles though as they will possibly double the overall price!
If you need to know what profiles go where drop me a line as I got a very helpful diagram from one of the techs at Marley.
Looks good though, seems easy to fit, and loads of colour options.
We’re doing our house by the beach next week.

Nickjb, I know your sketch above was probably intended to show slab build up only, but it also shows external timber cladding taken down to below external ground level. Any timber cladding should not touch the ground.

Any and all cladding should finish above ground…. Marley states 150mm minimum in their guide.

The timber in that sketch is labelled formwork; it’s the shuttering for pouring the concrete. Anyway, good point on cladding.

Bit more messing about today after a ride this morning. Didnt get to fitting the roof ply so hopefully do that tomorrow pm. Ran out of screws so couldnt finish the other overhang. Off to walk the dog to the pub 🙂

[/url]20170702_132621 by mcivord[/url], on Flickr[/img]

[/url]20170513_204330 by mcivord[/url], on Flickr[/img]

Keep the pics coming. Be interested in the detail of the roof.

R

That’s similar to what I was planning, cedral cladding, tata colorcoat urban roof if we had enough in the budget, otherwise Firestone EPDM, was going to be my new garden office as I work from home most of the week. But ‘we’, have now decided that the front of the house needs doing first, so now I have 56 lengths of beige Cedral cladding sitting on pallets, so if anyone needs some drop me a line.

If you were looking at wood cladding have you looked at http://www.silvatimber.co.uk, sometimes they do deals on trade packs or end of contract stuff they have left over.

Thanks Reign_man

I will be using EPDM as the roof pitch is small. This plus the fact that I wont be able to see it!

Thanks for the link!

Quick question about my build…..

Bad weather, holiday and job hunting have taken priority so not much progress the last few weeks, plus I am not in a hurry so not beating myself up too much to finish. Timeline is Watertight before end of September.

Anyway I was trimming the joists for the rear overhang when I realised even though the frame is quite substantial and bolted to the concrete etc I was suprised at the amount of Flex when I was at roof level. I was hoping to put the first 18mm ply sheets on the roof but a bit concerned I would cause sme damage climbing on it. I had planned to fix the housewrap to the frame then batten and clad over that, then board the inside but I think I will put 12mm board on the outside just to stiffen it up. My plan now for the walls is:

12mm Ply inside, 2×4 frame (with insulation), 12mm board, batten, housewrap, Cedar cladding (Vertical)

Will this be OK or do I need another batten between the outer board and the housewrap?

Cheers

My build has been covered in polythene to keep the rain of the Ply but later today looks like an opportunity to finally get the EPDM on. Any tips?????

Exscuse the jaunty angle, pic taken by Surfer junior

Any tips?????

If using non-water based contact adhesive don’t use a foam roller – they melt quite spectacularly. Take your time spreading the adhesive ( I used a large paint brush with firmish bristles) and get an nice even layer – if you don’t it’ll show up later. Use a hard roller if you can and work towards the edges, re-lifting if needed to free any air pockets.

If solvent based, don’t be shocked when you wake up to find it covered in tiny raises – it’s par for the course and will disappear in time.

Don’t inhale too many fumes and fall off the roof. 🙂

Thanks Teasel 🙂 Falling off is a real risk for me.

I have water based adhesive

Crack on with a roller, then. You’ll get a nice even layer much easier than with a brush.

Also, if it’s large enough there’ll be seams on the sheet (there was on mine). I didn’t pay enough attention when I laid mine and the seam faces upward to the highest point. If I could have done it again I’d have the seam face, as it were, facing downwards towards the guttering. I doubt it makes any difference but it still gives rise to a little snarl when I catch sight of it.

I bought the EPDM as one sheet which may make it “interesting” to install on my own (my home bred labour force left for uni on Saturday) Fortunately we wont see the roof (well only from the bedroom windows) as it slopes away 🙂