stunotch

Ok thanks, maybe no need for 150mm. Should I start the first course upright then, and cut the door in?

Hi, The footings are level, they used their posh laser level which was a lot better than mine! I've got the 75mm insulation slabs, and Taylor Wimpey guys suggested 150mm concrete floor? Do you think that is too thick then? If I was to build the 1st course to slab level, then that would be higher than needed though? (The height of a block / 215mm, if I don't lay the first block on its side?)

I cant remember why they said to have it poured to the top now, but it did make sense at the time and they should know what they are doing having built nearly 300 houses behind! But I am also now thinking that the block on its side will be visible? Hmmmm.... Should I maybe not lay the first block on its side??

Thanks, I managed to get the groundsmen from the Taylor Wimpey development behind my house to pour the concrete over the wall for me, I originally planned to have it lower, but they convinced me that it was better to bring it up to that level to start the first course. The floor will still be at the same level because that is the level the ground is at in the centre, where I will be pouring the floor. It was always going to be 225mm higher.

I've now got the foundations poured and just looking at setting out the first course. I plan to lay the first course of blocks on their sides and then a second course normally. I'll then look at putting the DPC & insulation down before pouring the floor. I've got 75mm insulation and was thinking 150mm for the concrete floor, sound about right? Questions though! How do I manage where the door is going? Do I just cut a concrete block so it is level with my finished floor level where the opening will be? The height of the second course will obviously be too high. Do I cut this opening before I lay the floor?

I will hopefully be getting the concrete from the Taylor Wimpey site behind my house, they will pour it over the wall, so I can take just what I need, as they will be using the rest else where on site. That will also solve a number of problems. Why the one trench is 30cm is because I dug down until I got to solid ground, there was a lot of loose mud and so that trench is deeper. It won't matter that some areas are deeper will it? I do have quite a bit of rubble lying about, so I could have some at the ready to throw in with the concrete perhaps? As I say, I've knocked in 3 stakes with a pencil line marking the level, and tied pink builders string between each stake so as the concrete goes in I can shovel it around until i can get it somewhere near the string levels. I Hope this works out! Its the first time I will have done this!! 😟

I've just set out my levels for the foundations with a laser level. At the highest point in the foundation I have actually hit solid rock, but this means the concrete in that location will only be around 13cm thick when poured. Is this acceptable considering it is on top of very firm ground? The opposite side of the foundations will be almost 30cm of concrete. I know the concrete will almost find its own level, but I have knocked wooden stakes in to the ground and marked the level the concrete needs to be at, and have also tied builders string between the stakes as a visual guide for the concrete level... Any other tips before the concrete comes?!

I was wondering if I can use the concrete slab that I broke up, maybe break that in to small pieces as its currently in big bits. Would make sense to recycle. I looked at hiring a concrete crusher but not worth it cost wise unfortunately. So the DPC should go down on top of a bed of sand which is on top of hardcore essentially?

Question .. Before I pour the concrete floor/slab, obviously I'm going to put a DPC and insulation down, but what should go under the DPC and essentially on top of the earth that is currently there? Stone dust or chippings? And how much of it? Thanks 👍

I checked, and don't need building regs.

After reading through this forum and others, seemed like 500mm width would be about right? I want it to last!

Well, I've made a start! Decided to dig the footings by hand - my back regretted it immediately but it's done now and I've saved £300 on digger hire I've just borrowed my friends posh laser level so I can mark the levels for the concrete, and maybe some good news - One of the builders on the Taylor Wimpey site rekons he can arrange for them to pump the concrete over the back wall for me! That would be a big help.

I've spoken to the planning officer today, same chap that recently signed of our plans for a double storey extension. He has said it wont require planning permission so long as the ridge of the roof is a max of 3m. So, i'm trying to work out, how to work out the roof pitch and height. The building will be 4M square, and I think the eaves height would be 2.5M. How do I work this out? I have broken up the existing concrete slab over the weekend and cleared the site, and hoping to hire a 0.8ton excavator maybe this week to dig the footings.

Unfortunately, its a Taylor Wimpey development, there is little to no chance that they would help in that way.

Ah thanks, that's really useful. So it would be an advantage to build using hollow blocks as I would have no need for internal piers. Although I imagine laying hollow blocks is probably more fiddly than standard blocks when putting the mortar down?

Thanks, and would this be the same if I opted to build using hollow concrete blocks?

What are peoples thoughts on using the hollow blocks? and would this mean I wouldn't require piers? Thanks.

I have recently had planning permission approved for a large double storey side extension on the house, went through with no issues. The neighbour has a 7x8M double storey garage right next to the boundary where I want to build mine, and a new housing estate that is being built in the field behind my house is building a double garage with pitch roof directly behind my boundary wall where I want to build mine. So I can't imagine there would be any issues at all getting planning for a pitch roof. I will contact the planning officer to discuss it and see what he says. Either way, I can still get on with the ground works, if it is simple enough to get planning I will do, if it isn't straight forward then I can change the roof design to keep within the 2.5M I plan to hire a micro digger to do the footings, Above I see @Conor suggested removing the old slab. There was a few reasons I though it best to keep it there, despite it being a bit cracked and old, I thought it might provide a solid base? Then there is the issue of removing the old concrete waste and having to hire a bigger skip, more cost etc, and where the workshop is being built is at the end of our garden which is quite long, so quite a number of wheelbarrows up and down the garden to remove it all! However, as I said, I am a novice to this, and if the advice is that it is best to remove the concrete and start again then I will do. Thanks all.

Yes it is within permitted development, but the building already appears on the title deed also.

Was planning on a slate roof, to match what is on the house.

Good to know.

Hi, Thanks for adding me to the forum. I am about to build a workshop in my garden and would love some help and tips having never built a building from scratch before! I've posted in the relevant section.

Hi, I'm planning to build a concrete block workshop at the end of my garden, replacing a rotten old wooden shed. Although I would consider myself to be more than competent at general building work, I have never built a building from scratch, so would like some advice! I currently have an old concrete slab which is a bit broken and cracked, but I believe will make a reasonable base to eventually pour my new floor slab on to. (Photo attached) The workshop will be 4m X 4m, with a door on one side and a window to the front, I also want it to have a pitch roof. Questions I have so far!: How deep should footings be? The land has quite solid bedrock about a foot under the topsoil !! I will be putting a DPC sheet across the existing concrete slab, with insulation on top before pouring my concrete floor, how thick should the insulation be? and how thick should the concrete floor be? How high above the new finished floor level should the first courses be before putting the DPC in? I was considering building a cavity wall to prevent damp, as I will be storing tools I didn't want them getting rusty etc., however this would increase the cost quite a bit, so I am now considering using hollow concrete blocks instead. Would this be a reasonable alternative? I read they offer a much higher insulation value than single blocks? If I do use hollow concrete blocks (440x215x215), with the wall length of 4M, does this mean I wouldn't require piers? Do I need to work from detailed plans? As a small 4M square building is there anything I would need to have calculated? Or should this be a straight forward build. How do I decide on the roof pitch? Any other tips / help would be much appreciated. Thanks.