Shed build design advice required

[hooblah]

I'm planning on building a shed in my garden. I've never attempted anything like this so I need some advice and critique from those with more experience.

7m long and 4m to 4.5m wide. 2.4m high. Yes i'm aware of planning and building control regs.
I've drawn it up in sketchup. It comprises of a concrete base with a 2x4 timber frame, and 2x6 roof joists. All spaced at 600mm centres. The outside will be sheathed in 11mm OSB.
There will be a large access door at the front. A window will be added in somewhere, i've put it at the end for now.
The roof slope is around 1 degree with the fall right to left.

Unknowns:
- Roofing. I can't believe there's no option that doesn't cost a grand or more.
- Cladding. Might go with steel sheets on the hidden sides.
- I was thinking I might OSB the inside and paint it white. Not sure if OSB is good look though?
- Should I place it on a course of bricks or bolt it direct to the concrete base?
- Sliding patio door or bifolding?
- Joist hangers or cut birds mouths?
- I've got a 1st fix nail gun. Can I nail everything instead of screwing?
- Should I build it out of block instead?
- So far materials cost is £1300ish just for the timber and OSB. What would the price difference be with blocks?

 

[iNf]

1st glance the roof slope seems too shallow. I think bare Osb on the inside looks good but obviously painting it white makes everything brighter. Is it for a workshop or garden room? If the 1st then glass doors that show everything inside and give easier access is not the best for security. If using as a workshop or accommodation don't forget insulation. Can't see a problem with the nail gun. Ideally you'd want the outside to slightly overhang the slab.

 

[Screwdriver]

Very similar to my own build in terms of size. I would definitely say go for block walls, cheaper, stronger, better.

Also, if you're going with breeze blocks (heavyweight concrete ones!) then it will force you to pour a decent slab. Whatever you do, don't skimp on the floor! Strip foundations will help tremendously to build a really decent flat solid floor.

 

[Screwdriver]

I second that regards the roof pitch. It will affect the total cost because trust me, you will want a decent fall on the roof but a level ceiling inside. When I built mine it had an apex roof but the council made me take it off, so I ended up having to jack up one side of the roof which gave me a slanted ceiling (it was horribly disorienting!)

 

[gaz1]

blocks are cheaper unless you get a builder in to build them

+ you need a waterproof coating on outside the roof is the same but you need roof straps

a note has to be said no insulation at the walls

 

[Screwdriver]

Hey, you're in South London! Give me a ping if you ever need a hand. I haven't built a shed in ages - great fun!

 

[Screwdriver]

I'm planning on building a shed in my garden. I've never attempted anything like this so I need some advice and critique from those with more experience.

7m long and 4m to 4.5m wide. 2.4m high. Yes i'm aware of planning and building control regs.
I've drawn it up in sketchup. It comprises of a concrete base with a 2x4 timber frame, and 2x6 roof joists. All spaced at 600mm centres. The outside will be sheathed in 11mm OSB.
There will be a large access door at the front. A window will be added in somewhere, i've put it at the end for now.
The roof slope is around 1 degree with the fall right to left.

Unknowns:
- Roofing. I can't believe there's no option that doesn't cost a grand or more.
- Cladding. Might go with steel sheets on the hidden sides.
- I was thinking I might OSB the inside and paint it white. Not sure if OSB is good look though?
- Should I place it on a course of bricks or bolt it direct to the concrete base?
- Sliding patio door or bifolding?
- Joist hangers or cut birds mouths?
- I've got a 1st fix nail gun. Can I nail everything instead of screwing?
- Should I build it out of block instead?
- So far materials cost is £1300ish just for the timber and OSB. What would the price difference be with blocks?

I would put the fall front to back, lot less wood, you'll need gutters anyway.
I kept on the lookout for cheap secondhand or misordered windows, score some hilariously expensive storm windows for pennies on the pound then designed the shed around those.
Roof was the most expensive part of my build too, it just is. Consider 400mm centres, won't cost much more but will be much stronger.
Maybe have a look at RR Buildings on YouTube for inspiration re: post framing. You might find some inspiration plus if you go all wood, you might consider stronger corner posts and/or bolt in supports.
Patio door would be a PITA if it's going to be a workshop...
Joist hangers much easier/quicker and more accurate (especially for a one man build)
If building with blocks, will be worth buying a secondhand concrete mixer, sell it when done, thank me later. You may struggle to do a 7x4 M slab in one go even with a mixer. Worth checking prices for mix-on-site delivery.
IIRC blockwork was comfortably half the cost of wood+battens+cladding. Maybe 1/3rd...

 

[finyuk2005]

check rubberroofs4u website, they have a calculator that can give you a quote for a full EPDM kit, i did a porch with it and was very impressed, easy to do also!
you could also stick some PIR insulation under it if funds can stretch, would make a very good roof, and no condensation like you can get with tin roofs

 

[Seadog]

I'd second rubber.

 

[Farside]

I'd second rubber.

Can't be too careful these days.

 

[Argonman]

Here’s one i prepared earlier. Similar to your design.

 

[Argonman]

Finished item. 2 inch kingspan insulated throughout. Interior lined OSB.

 

[Screwdriver]

Nice! £5-£6 grand ish??

 

[Argonman]

Nice! £5-£6 grand ish??

Built 4 years ago. Came in at 5K including base & tool hire. All done by me and Mrs Argonman.

 

[Screwdriver]

Looks very well made, worth every penny. I was assuming a self build of course, having something like that built would be a LOT more...

 

[addjunkie]

Id go ring of bricks around the base to keep any wood dry, doc the fix to bricks ( semi engineering). More slope on the roof, and a gutters to catch rain.

First fix nail gun would work…

 

[CompoSimmonite]

I used moisture resistant OSB, which was then painted and clad in UPVC in one area and plastic coated galv steel in others, for the facia of my carport.
Despite being "moisture resistant", and not being in direct contact with rain etc, the OSB has deteriorated so will need replacing IDC.
I'd therefore rethink your idea of using OSB for the exterior cladding unless it will be a base for being covered with something else.

 

[Argonman]

Looks very well made, worth every penny. I was assuming a self build of course, having something like that built would be a LOT more...

Thanks. It is my motorcycle workshop hence the larger hidden door on the end. I allowed a 2 inch fall on the roof from the front elevation to the rear where the run off is collected in a water butt via gutters. This feeds next door’s pond which is a nice way of disposing of the excess water.

The overhang on the roof keeps the outer walls dry apart from the windiest conditions. An electric fan heater, switched on for 30 mins keeps the shed warm enough to work in even in the coldest snaps.