Yet another shedshop Mike's way. Ish

[aphillippe]

Long time lurker embarking on a shed build and thought I'd start a build thread.

In my previous house I had an off the shelf 14x8 'heavy duty' shed that acted as a workshop, timber store, bike storage, garden storage, etc. etc. I moved last year to a larger property and while we were looking around, one of the things on my list of requirements was a decent workshop space. The house we ended up buying has no workshop but plenty of garden. So permission and budget was negotiated, planning permission was sought (Guernsey planning permission is a little stricter in certain ways than UK) and a couple of weeks ago the build started.

So budget and WAF will stretch to a 20x10 timber frame on a concrete base. Not enormous but twice the size as my previous shed and, crucially, entirely devoted to workshop space. I'm planning on following Mike's design mostly, concrete base, two courses of bricks, floating kingspan/chipboard floor over the concrete, timber frame, OSB inside, wrap and cladding outside. I'm thinking of following the design of my previous shed for the roof, gabled end wall framing, then two trusses and six framed roof panels that will be easy for me to lift and slot on the trusses. Then onduline sheets or EDPM, haven't decided yet.

I've got an overall budget of £5.5k, which is going to be pushed very hard. Guernsey is not cheap for building materials at the best of times but timber prices lately mean I'm going to have to get creative. I'll be building mostly at weekends in between full time job, three kids and a dog so progress it likely to be slow but I'd like to get it up and done (or at least water tight) over the summer. Time will tell...

 

[Fidget]

Good luck, looking forward to seeing your progress

 

[Fitzroy]

Super! Take lots of photos, we all love those. Personally I’d go epdm, I found it a very easy and cost effective route.

I kept the build cost down on my build by doing more of the work myself, slowed the build down but lowers cost. I bought double glazed units but made the frame last myself. I bought rough sawn larch boards from a local saw mill for cladding, picked them up myself and put them through the Thicknesser. Many hours of work, but my time is ‘free’. I also surfed GumTree continually for materials that were surplus and cheap.

Fitz

 

[aphillippe]

progress so far...

I don't have a good photo of the site before starting. There's an area around the side of the house that had two 10x8 sheds. One of them was rotten so that came down. Needed a gap in the fence where the shed was filling, then the area clearing and digging down. I was assuming there would just be soil and rocks etc but ended up finding a nice flat level compacted bed about two inches down through the soft top soil, about where I was planning on laying hardcore. It took some effort to get a spade through but was about 6 inches deep, a perfect bed to pour on to. I knew the area was used decades ago for the local horticultural industry so this must have been the bases of the old glass houses. Bargain, saved me a couple hundred quid and a lot of work.

So, starting on the form, I used 18mm ply, cut to 15cm strips with 3x2 timber spikes every so often. Original plan was 100 overall, thickening to 150 around the edges. The above changed that plan, since I had a nice level base already laid. The site is slightly sloped from the back right corner to the front left, about 10 cm over the 7m diagonal, so not too much to worry about. So the bottom of the front of the slab is about level with ground level, and about 10cm down at the back, leaving the top about 5cm proud at the back. Probably should have been more in hindsight but I can always dig out around there if needed. I was planning on supporting the form with dirt so wasn't too worried about strength of the form.

Please ignore the messy site, I have a large garden but a small WAF budget for spillover of my 'dirty building stuff' into the main area of the garden. Organisation and tidiness are a work in progress

Form in progress...

Form complete...

Filling with sand blind and levelling/flattening (child number 3 helping out)...

Finished sand blind and DPM in place to be rolled out ready for concrete...

Concrete going in...

I was very lucky to have a mate available (pictured) to help with the pour and levelling. This was my first concrete pour and mostly went smoothly. A couple of issues, nothing too major. I used a straight 3x2 to screed and then a home made bull float to get a reasonable finish. Not perfect but flat, smooth and level and will be covered by insulation and flooring anyway

 

[Spectric]

What no steel mesh, cheap as chips but can make a big difference to cracking.

 

[aphillippe]

The concrete guy said the base was solid enough and had been down for long enough that reinforcing the concrete wouldn't do much. Probably should have belted and braced it but I took his advice

 

[Adam W.]

It'll be alright.

 

[Cooper]

My shed workshop was a much more modest project but one thing I'm really pleased It did was to have a significant overhang/porch over the entrance and an overhang and gutters at the sides. The walls and door apart from in the most stormy weather are always more or less dry and still in very good condition. I also have water buts which are useful for my beans. On so many sheds the water from the roof runs down the walls, which can't be good.

 

[Sheptonphil]

Great progress, love these build WIPs.
keep the pics coming, a great record for you, and a superb source of information for others thinking of this type of build.

 

[aphillippe]

Small amount of progress this week. I unwrapped the concrete base and had a look around it. Not perfect but it'll do. Timber and bricks have arrived. Bricks will be this weekend's job.

 

[aphillippe]

First question. How far up should the damp proof membrane go? As far as I see there are five options;

1. trim it off at the bottom of the concrete base
2. trim it off at the top of the concrete/bottom of the bricks
3. trim it off roughly at ground level
4. leave it go all the way up, over the bricks and tuck under DPC
5. trim it wherever. You're totally over thinking this whole thing and it doesn't make any difference

I'm discounting number 4 as that seems ridiculous. So I'm thinking number 1 or 3?

 

[shed9]

Watching this one.

Couple of notes from my own experience. I think the proposed initial budget is very tight and will be very surprised if you end up in that area at the end of the build. Secondly, check suppliers of Onduline products as availability is not great at the moment with Onduline direct sometimes being the only viable source. Their shipping costs need to be factored in if you go this route as they are not cheap by any stretch.

Finally got my restart of my own build together over the last weekend. I poured the initial concrete a few years back but life took over and for what it's worth I trimmed the DPM with about 12" spare around so I have options if need be. I have most of the materials already but had the choice of steel or timber frame so I built a test workshop last year (on raised timber structure) of 8'x16' from timber to check if I was comfortable with that main building design - which I am. That is a timber frame, wrapped in Onuditiss Air95 and clad in metal on the outer and 18mm ply for internal walls. My new workshop build is 14'x25' which will again follow a similar design but with Tyvek products (standard and Supro) to wrap it as they have a longer pre clad life than Onduline's wrap. My budget is fairly high but then I've ordered bespoke aluminium doors and windows to cover over 9m2 of glass of that all important light and that is over half the budget in itself.

The reason for the long blurb up there ^ is not to hijack your thread, more to point out I'm doing a similar build along the same time frame as yourself. We may be able to learn from each other in the process.

 

[Fitzroy]

Are you using the slab as your finished floor or are you putting in an insulated floating floor?

 

[paisawood]

First question. How far up should the damp proof membrane go? As far as I see there are five options;

1. trim it off at the bottom of the concrete base
2. trim it off at the top of the concrete/bottom of the bricks
3. trim it off roughly at ground level
4. leave it go all the way up, over the bricks and tuck under DPC
5. trim it wherever. You're totally over thinking this whole thing and it doesn't make any difference

Trim the DPC at ground level. As shown on Mike's drawing there should be a 50mm gap between ground level and the first course of bricks to ensure that the concrete remains dry.

 

[aphillippe]

Are you using the slab as your finished floor or are you putting in an insulated floating floor?

insulated floating floor is the plan. Don't fancy standing on cold concrete for hours. I don't know how I'm going to finish the floor at the threshold yet. Future problem

 

[aphillippe]

I think the proposed initial budget is very tight

Yes, very tight. I'm aiming for a 10/15 year lifespan minimum as we're planning on moving around then to downsize when the kids disappear so there are a few concessions I can make. And I'm doing as much of the work myself as I can to keep labour costs to 0. But even then I think I might need a bit more budget. We'll see.

 

[Fitzroy]

So long as the ground around the slab does not contact the edge of the slab the only route for moisture to enter the slab will be rain splashing on to the edge of the slab. This will happen up to c. 20cm and is the purpose of the brick courses to keep the wood out the splash zone.

With the slab as the floor I’d perhaps be thinking about other measures to avoid splashing water wicking into the slab. However with a insulated floor and following mikes guidance in this area. If wicking were to occur you’d never be bothered by it.

As others as have advised trim DPM at ground level and avoid and earth touching the slab edge.

 

[clogs]

before u get to far with materials look at insulated steel panels roof and walls.....
my new shed (160m2) will get them.....
I have to buy new as so far there's no used stuff available on this island....but for you the UK is easy shipping distance....
reasons, easy to fit, lightweight, no maintainence....will last almost forever.....
and when it comes to selling up it's an asset not some 1/2 rotten wooden shed....
not saying ur's will be but it's what prospective buyers will say/look at.......
My windows will be used double glaze'd units.......
on the houses I've bought n sold where a steel shed was built I more than doubled the cost as profit ....
a def plus point.....a good way to get the use out of it and make money...

 

[aphillippe]

before u get to far with materials look at insulated steel panels roof and walls.....

Is that just using the panels as loadbearing walls? Or mounting to the outside of a timber frame? I was looking in to them a while ago after watching a couple of youtube videos but I'm not familiar, and there are no local suppliers to speak to. So I chickened out

 

[MikeJhn]

The concrete guy said the base was solid enough and had been down for long enough that reinforcing the concrete wouldn't do much. Probably should have belted and braced it but I took his advice

This concrete guy, was he the lorry driver or a Structural Engineer?