Foundations to DPC help

[Suki Nandhra]

Thanks for taking the time to answer this. I am planning on building an outbuilding at the end of the garden within the 2.5m height restriction.

It’ll rough be 4.7m x 2m. I’ll have trench filled concrete footings possibly 450mm wide x 600mm deep (these are the dimensions of the concrete), above that will have around a further 200 - 300 mm deep footings the exterior isn't level (it has a slight drop decline)

The original plan was to build out of the trench with Yorkshire stone work (single akin at 140mm on the bed). Would recommend this or would it be better to bring out to dpc level in blockwork (around 150mm above the exterior ground (at the highest point and then render this (on the outside) with sand and cement. Then lay the Yorkshire stonework on top of these 7n blocks with the dpc and dpm tucked into the bit between the block work and Yorkshire stonework? The inside will have a 100 - 150mm concrete slab dropped in.

Dependent on which builder I ask they completely contradict each other. Looking online there’s a plethora of info but nothing that says this is a better option Over the other?

By the way it will have a wall plate and a flat roof using 6 x 2 rafters and firings under a
Fibreglass roof.

Any advice from you would be greatly appreciated.

 

[Scarlet Pimpernel]

Use blocks to just below ground level, then use engineering bricks to dpc.
You could use blocks to dpc, and you don't need to render them, but for aesthetics, bricks are better.
Render on blocks below and in contact with the ground would be susceptible to problems.

 

[JohnD]

I'm not used to Yorkshire stone.

If it is suitable for below-ground work, I think the house will look better if it grows out of the ground in stonework.

If not, engineering bricks up to DPC can IMO look very handsome. I don't know what colour would tone with your stone, as the ones I see are invariably either deep red or slate blue.

Blocks look very offensive to me if visible above the ground. Not too bad if they are rendered but you have to take care not to bridge the DPC.

 

[Suki Nandhra]

Thanks both for your input.

I’m still undecided as the Yorkshire stone is 140mm in the bed obtaining engineering bricks to suit is going to be a challenge and so is cutting them to size so they all look uniform from the inside too.

On reflection I agree with your comments regarding render being a potential problem in the future so maybe blockwork to just below ground level, then Yorkshure bricks to dpc and again Yorkshire bricks above? im just so torn.

 

[^woody^]

Presumably Yorkshire stone is more expensive to buy and to lay that blocks or bricks, so why would you want to use it in the ground where you wont see it?

 

[JohnD]

I'd use enough that there is no risk of the bare blocks ever being seen. That would mean the stone went a bit below final ground level, especially in flowerbeds which will sink a bit after the builders have left.

presumably the old local stone houses would have been stone down to the footings.

I do think an engineering brick below DPC level can look very handsome, as in Nosey's recent wall pics; but I don't think it would match the stone colour.

 

[Suki Nandhra]

Sorry guys, I’ve been away with work and only got back late last night.

The reason why I’d want to start with it just below ground level is so that if I’m the future our plans change around the garden we can change the external height without worrying about it. Secondly I agree that the bare bricks would look nice but gaining and cutting them at 140mm is going to be somewhat of a challenge.

I’m now edging towards 7n blockwork to about 100mm below ground level, then use the Yorkshire stonework to DPC level. Drop in the DPC and DPM, internal slab and continue with the Yorkshire stone to wallplate.
That sound ok to you guys please?

 

[Suki Nandhra]

Hi guys another question and looks like there’s various schools of thought on this.

It’s regarding the DPC and DPM. What’s the correct way to install both the items.
I was thinking lay a thin bit of muck, drop in the DPM, then another layer of muck and lay the DPC, then lay a further bit of muck then the next course of Yorkshire stonework.

Would you agree with this principle on a single skin Yorkshire stone wall. I can then cut the DPM once the mortar has dried?

Is this the correct way to do this?