Diy garden office/summer house/shed

Are there any guides on how to design and build?

Not looking for anything fancy (a basic rectangle with flat sloping roof, a couple of doors and windows) but will be pretty large.

I don’t know of any, designed my shed but that’s a fairly simple/small lean to. Sketched it out on paper and just nailed stuff together. Parents have just decided it’s easier to buy one and have someone (me) put it together.

If it was me doing it again and I wanted something fairly straightforward I’d just buy one. The only reason I’d design/build is if I wanted something for an odd shape or certain features.

There must be a bit of mark up in the flat pack ones though?

Fair chunk of time saving of course though.

Check out Oakwood garden rooms on YouTube, they are pretty comprehensive videos and they offer a build pack with all materials listed for a given size so you shouldn’t have any wastage.

There’s been a few threads on here over the years, and there is a rabbit Warren you can go down on YouTube.

I built this one from scratch after buying one (that cost a chunk more than this did…) that ended up being very very poor quality and got sent back. (I set the roof out in CAD, only because I could easily, lol). I work in construction (driving a desk these days mind) and qualified as a joiner back in the day, so had some idea going into it.

i built a 6m x 3m one recently, essentially same as the one you describe, with 2nd hand doors and windows.

best advice i got was to just make sure all the main timbers are at 400mm centers, and all the overall dimensions are at multiples of 400. this makes life so much easier when installing your floor, roof and wall panels, assuming you are using large sheet material, OSB or whatever as it usually comes in 1200×2400. plus you can always work out where the structural beams/posts are in future (unless you leave them exposed? depends if insulating or not…) handy when throwing up shelves etc…

pre-fabbed the wall and floor frames in the garage, (larger lengths in 2 sections) and fixed them all together at the site. built the roof insitu and hey presto – shed appeared in a weekend! took another 12 months to finish it tho! 😀

There must be a bit of mark up in the flat pack ones though?

Perhaps not due to them buying materials in huge volumes and have big manufacturing set-ups doing repetitive jobs.
Far more satisfying to design and build your own, but sadly not strictly cheaper necessarily.

There aren’t many detailed plans but there are hundreds of videos and forum posts about builds. You’ll have to do some searching then pick the bits you like, eg here’s Colin Furze’s shed build:

I was about to link to the colin furze video….
I actually think it’s a pretty good explanation…

If you figure out how the walls are made (as in his video) then you just need to vary the lengths to your design. I want to do something similar when I move – make a summer house using old/discarded windows and patio doors.
I’ve a builder mate who will pour the base and lay a brick layer for the first course..

DrP

thanks all. I’m over thinking things if worrying about wood expansion / contraction allowances then – Just screw the 4 x 2’s together.

The plan is to insulate it, ideally the walls and roof.

Wood moves a bit but the frame won’t move much. As you say, just screw the 4x2s together. Only concern might be cladding which can open up a bit, or start to pull the fixings out. Not a big issue.

It’s just made some garden gates that seem to have a pretty big change in size over the year. I suppose they are more exposed to the elements and swell when wet, and so why you say the cladding rather than structure is more at risk..

@muddyjames What timber and treatment(s) did you use?

I’m thinking of making some driveway gates incorporating something like C16 75 x 50 for the frame/bracing, and planed T&G. All will be treated with Barrettine preserver.

I didn’t treat them with anything as they were pretreated.. maybe that’s one area where I went wrong. I also don’t think they were kiln dried again another wrong too probably. I don’t remember exactly but I think largely constructed out of something like this (both the z-frame and panels), with edges of the panels routed to fit together without gaps:

https://www.wickes.co.uk/Wickes-Treated-Sawn-Timber—22-x-150-x-2400mm/p/9000263484

Well done. I also want to make a garden office. Any suggestions for a beginner?

I went with a log cabin from powersheds.

Pro’s – wasn’t actually that much more than the cost of materials was looking to end up for something similarly substantial. And there were almost no arguments between me and the OH when putting it up.

Cons – There’s things I’d do differently. Their floor for example is obviously in hindsight only going to work on a permeable base not on a concrete slab as once water runs under it there’s nowhere for it to go as it’s not ventilated.

I made foundations from holes filled with concrete and then concrete blocks (not breeze blocks) and a raft of big timber. Mine was going to support a 100 litre hut tub so they had to hold a ton just for the water.

The walls were all either 2.4m or 3.6m panels and 1.8m high. It saved an awful lot of time and sawing as that is standard timber lengths. If you can use those dimensions in your design then I can strongly recommend the approach.

This was it once the structure was done but before we landscaped the outside. It took MrsWCA and I about a month from breaking the soil to popping the champagne in the hot tub.

We diy’d this other than the plastering, having never built anything before. Watch Ali Dymock’s series of videos on YouTube, he explains things well, but as he points out, there’s a hundreds different ways to do the same thing. Digger hire week was the best week ever!

Insulated roof panels.
Look expensive at first, but they include your insulation, need less supports, you can walk all over them and really quick to complete once getting the first one alligned.

Timber sheet is your unit of measurement.

I looked at stick-building a shed from timber, but in the end it wasn’t a lot more to buy a kit from Tuin – we’re pretty exposed with regular storm-force winds and your regular B&Q job would just blow-away. The other benefit of a kit is the quality and fit of doors and windows. Foundations are concrete to which the timber walls are firmly screwed. Roof is corrugated steel.