Advice re block wall

emptyshed

Hi Folks,
apologies if these are silly questions.

Have a small lean too type boiler block shed on the side of the house, with a laneway/side entrance to the side.

Planning on knocking whats there and just extending to the side, encorporating the side entrance.

Basically looking to go about 12 cavity blocks high, 11 blocks long and 8 wide.
Roof will be lightweight corrugated type, just a storage shed/ man hiding cave when necessary.

Theres currrently a concrete slab of ground, which appears to be about 6 inches deep.

Question is, is the slab enough for foundation, the existing block shed has stood for 20+ years.

Anyone know whats the going rate for block laying..... I'm guessing roughly 200 blocks for the two walls to be built. (allowing for double doors etc).

Cheers inn advance.

Poor Uncle Tom

First of all, nobody on here can answer whether the existing 150mm thick slab is good enough to take a fresh build. That is a question for an on-site professional, besides it is against the forum charter.

Just a few points, a single leaf cavity block build will most likely lead to a damp store/retreat/area. The location of the existing slab in relation to the floor level of the house will have a bearing on dampness too. Is there a Damp Proof Membrane or insulation underneath the existing slab?

The build size is roughly 4.95m x 3.60m to be used for storage onto the side of the house, planning permission is needed for this.

Take a little time now to plan the area you want properly, it will make for a far better finished build with far fewer problems later.

BryanF

you require planning as your proposed extension is to the side of your house

re foundations: Go dig (as in dig a hole externally by the side of your existing wall) then get a structural engineer round to inspect whether foundations are adequate.

going rate for laying blocks seems to vary widely depending on where your living? + the grief: as in your up against a boundary wall?

emptyshed

Cheers for the replies.

Have dug the hole already to repair a cracked drain!!

Appears to be about 6 inches of slab over a hardcore thats down at least 2 feet (didnt dig any further for my drain repair).

The slab is approximately 15 inches below the floor level of the house.

The existing shed was built to house the boiler, which so far has thrown off enough regular heat to keep it bone dry inside, despite a very basic corrugated metal roof with no insulation..... of course I'd be doubling the size of whats there already...so not sure if that will change things.

Would be building to an oldstyle boundry metal fence which has a similar shed on the other side....I was pretty much planning to copy next doors design, thereby not effecting them...i.e. not changing their view or blocking light.

Have spoken to them and they are enthusiastic.... threw me a few pointers on stuff they wished they'd done with theirs..... again theirs is pretty much a grden shed, storing garden tools etc.

Was planning it as a cheap project, so may reduce size if this avoidss planning issues.

BryanF

emptyshed wrote: »

Cheers for the replies.

Have dug the hole already to repair a cracked drain!!

Appears to be about 6 inches of slab over a hardcore thats down at least 2 feet (didnt dig any further for my drain repair).

The slab is approximately 15 inches below the floor level of the house.

The existing shed was built to house the boiler, which so far has thrown off enough regular heat to keep it bone dry inside, despite a very basic corrugated metal roof with no insulation..... of course I'd be doubling the size of whats there already...so not sure if that will change things.

Would be building to an oldstyle boundry metal fence which has a similar shed on the other side....I was pretty much planning to copy next doors design, thereby not effecting them...i.e. not changing their view or blocking light.

Have spoken to them and they are enthusiastic.... threw me a few pointers on stuff they wished they'd done with theirs..... again theirs is pretty much a grden shed, storing garden tools etc.

Was planning it as a cheap project, so may reduce size if this avoidss planning issues.

get an arch/arch tech out to have a look at planning and construction issues
you need an an engineer re foundations

Poor Uncle Tom

emptyshed wrote: »

Cheers for the replies.

Have dug the hole already to repair a cracked drain!!

Appears to be about 6 inches of slab over a hardcore thats down at least 2 feet (didnt dig any further for my drain repair).

The slab is approximately 15 inches below the floor level of the house.

The existing shed was built to house the boiler, which so far has thrown off enough regular heat to keep it bone dry inside, despite a very basic corrugated metal roof with no insulation..... of course I'd be doubling the size of whats there already...so not sure if that will change things.

Would be building to an oldstyle boundry metal fence which has a similar shed on the other side....I was pretty much planning to copy next doors design, thereby not effecting them...i.e. not changing their view or blocking light.

Have spoken to them and they are enthusiastic.... threw me a few pointers on stuff they wished they'd done with theirs..... again theirs is pretty much a grden shed, storing garden tools etc.

Was planning it as a cheap project, so may reduce size if this avoidss planning issues.

It could be doable, but it realy needs an on-site inspection to determine.

Regarding the planning permission aspect, it's not the size it's the use which determines that. A boiler house, per-se, is an exempted development. A hobby shed or a storage area onto the side of the house is not exempted regardless of the size, it needs planning permission.

martinn123

emptyshed wrote: »

The existing shed was built to house the boiler, which so far has thrown off enough regular heat to keep it bone dry inside, despite a very basic corrugated metal roof with no insulation..... of course I'd be doubling the size of whats there already...so not sure if that will change things.

Poor Uncle Tom wrote:

Regarding the planning permission aspect, it's not the size it's the use which determines that. A boiler house, per-se, is an exempted development. A hobby shed or a storage area onto the side of the house is not exempted regardless of the size, it needs planning permission.

Is the new shed still to be used as a boiler house, as you have not mentioned moving the boiler.?

emptyshed

Boiler is staying in the shed.

Currently I have a tiny workbench and my tools stored in there, while my poor motorbike sits outside in the rain. So the theory is to just make more efficent use of the space and have dry storage for the bike.

martinn123

emptyshed wrote: »

Boiler is staying in the shed.

Currently I have a tiny workbench and my tools stored in there, while my poor motorbike sits outside in the rain. So the theory is to just make more efficent use of the space and have dry storage for the bike.

In that case I think '' Poor Uncle Tom's'' quote above sums it up.

As a boiler house, its exempted, but as a storage shed, garage for Bike, hobby shed, man hiding cave, etc, you need advice as to planning.