Musings on building a workshop and a new machine...

[irving2008]

I looked on the government planning portal under the new 'deregulated' permissions. Its possible that the local council are prepared to relax these as the location in question is already screened by matured hedges/trees on 3 sides so will only be visible from my garden anyway... I'll have to ask informally and see how far I can get... if not, its only £58 to get the drawings reviewed... so thats my next task, do some scale drawings... Sketchup should do the job nicely. Been playing with Draftsight, but either its not intuitive or I've missed the point somewhere....

I'm also wondering about how much of this I can do myself... laying bricks/block can't be too hard? Not sure I fancy digging out 3tonnes odd of soil/clay/crap for the base. Clay subsoil so need to go down 1m under the walls and the floor is 20cm of packed MOT type 1 hardcore and 30cm of concrete then a membrane then screed on top of that - or somehting of that nature, still reading up on the actual requirements...


@Jonathan - if I go below ground level inside I'm going to have a step down. Building regs don't seem to like this as far as I can see, also it could be a pain to lift things in and out, I wanted flat access for a number of reasons...

edit: It seems that the old requirement of being at least 1m from the boundary no longer aplies if the construction is largely or wholly of non-combustible materials and bricks are that last time I looked, so i can make the floor area bigger by up to maybe a metre in each direction. The downside being it'll cost more, 30% bigger base area adds nearly £300 more concrete let alone the digging out costs...

[m_c]

I'm also wondering about how much of this I can do myself... laying bricks/block can't be too hard? Not sure I fancy digging out 3tonnes odd of soil/clay/crap for the base. Clay subsoil so need to go down 1m under the walls and the floor is 20cm of packed MOT type 1 hardcore and 30cm of concrete then a membrane then screed on top of that - or somehting of that nature, still reading up on the actual requirements...

That sounds a bit excessive to me.
All our sheds with concrete floors are on 10-12" type 1, then 6inch of reinforced concrete, with the damproof membrane below the concrete and brought out and up over enough layers of bricks to ensure it's above ground level. And those floors have had a fair bit of abuse (3 tonne forklift running over them, jacking up various tractors)
Only place near us thats got a 12" float foundation is the neighbours newbuild, as the test bore revealed mine workings below. All the original houses are on strip founds and none of them have fallen down yet! And all his damproofing went below the concrete.


One thing I would say, plan for insulation in the walls, but make sure you build the roof with insulation (i.e. suitably vented with insulation below). The one regret I've got is not doing the workshop roof properly for insulation. I do plan on insulating it, however it's not feasible to vent it properly, so it will probably eventually rot the main beams :-/

[irving2008]

Just been reading Building Regs Part A Section 2E..

Because of neighbouring trees the strip foundations need to be a min of 0.75m deep and 0.5m wide. I might be a little over the top on the concrete and not enough on the hardcore, but the foundations will be 2 brick courses below final floor level, thats 150mm or so, so there'll be at least 150-200mm of concrete. Already planned for the insulating fill between the walls, with special sound proofing stuff so I can work in the evenings. Roof will be pitched with internal dry-wall soundproof insulation and vapour barrier. There wont be a ceiling as such because i want to use the roof space.

I need to check with Planning I can have the pitched roof nearer to the boundary than normal; I cant see why not, its already well screened as i said. If I cant get that then it puts the rest of the works in doubt, or i'll have to rethink.

[Web Goblin]

The council dont like you building below the surface because of water ingress I think. If you did that you might need to tank the walls inside below the ground level. I built mine up two courses of concrete block and then timber framed it. Saved quite a bit of money because I did it all myself. I didnt fancy trying brickwork that high but a couple of courses was easy enough with my Brickies Mate laying tool. Insulated all the walls and roof with 100mm thick polystyrene and then clad the outside with plastic cladding. Looks nice even though I do say so myself. I also made the roof trusses from 100mm x 50mm to take extra weight and I use the space for storage. I also modified the roof structure to allow a bigger access to get larger and longer stuff up there.
I will try to post some photos later.

Ian

[irving2008]

Done some rethinking and some replanning and put some tent pegs and string in the garden where this is likely to go (not so much a garden as a unkempt undergrowth behind the trees). Reckon I can get 6.5 x 4m external which is 6 x 3.5 internal and I can keep it to 2.5m high by putting the door in the end and better utilising the space. So here is plan B in Sketchup this time...

Give me a continuous run of 6m of workbench with the lathe and grinder at the end, lots more windows and therefore light and room to put the bike trainer up when I can't get out and ride... and i could make it 0.5m narrower if need be (but I dont want to). Will make it a single pitch, 2.5m at the front sloping to 2.25m at the back (top of pic)

[JAZZCNC]

Make it taller than the inside on the outside?

Ye good idea then when it piss's down you have an indoor swimming pool as well. . . . Lol

[Web Goblin]

I wouldnt recommend a single pitch roof. I had this on my last workshop and I am glad I didnt do the same on the new one. Having the extra storage space is a major bonus on its own. But if you do go down that route go for some decent roof covering like plastic coated metal sheeting. Got that on mine and its great.
Photo of the enlarged access I left myself to get stuff into the roof storage area.

[irving2008]

I wouldnt recommend a single pitch roof. I had this on my last workshop and I am glad I didnt do the same on the new one. Having the extra storage space is a major bonus on its own. But if you do go down that route go for some decent roof covering like plastic coated metal sheeting. Got that on mine and its great.
Photo of the enlarged access I left myself to get stuff into the roof storage area.

Would prefer double pitch, but if its with 2m of the boundary and I dont want the hassle of applying for planning permission it has to be no more than 2.5m at the eaves, so will slope it to the back to allow water run off into a gutter and thence to a water butt with a overspill and soakaway. I've had all sorts of issues with a flat roof on a garage in the past so dont want a repeat of that. The only issue with plastic coated metal roofing is the noise it makes when it rains hard :) ... also not too sure of the sound insulating properties. I guess once its lined with 6cm of foam it'll be OK?

[Web Goblin]

If you are going to build to 2.5mts at one side anyway would you not be as well having a pitch roof? It might not be as much of a slope as you wanted but it would Still be there. The metal roof is not really that noisy and the roof sheets are screwed down on top of the outside sheet of timber anyway.
Photo below (left)shows my workshop roof. The photo on the right shows my nearly complete bike shed with the same type of roof. The roof has the outer sheet of osb, 100mm of poly insulation, then another sheet of osb inside so its well insulated for heat and sound.

[Web Goblin]

Forgot to add that the air gap between the roof timber sheet and the metal sheet gives it a good way to breath to keep the damp away.