Side house extension under permitted development

Oranjeboom

Hi All,

Not sure if this is the best tplace to post this...it's not quite a DIY job!

I am looking to extend a detached bungalow with a 'single' side extension under the PD (permitted development) guidelines. This seems possible to do as long as the extension:

- does not protrude the existing 'front' of the house (i.e. elevation of the front house)
- The house is not on designated land,
- width of side extesnion is not greater than 1/2 the width of the current house
- side extension should be single storey and no higher than 4m

Also, the house in question has never been extended before, sits in 1/2 acre of land (so new extension will not fill more than 50% of the garden) and the nearest boundary is more than 3m away.


I'm looking to add a 6x8m extension to the side of the house with a pitched roof (no higher than existing roof). Under PD, this needs to be a single storey extension.

1) Can I add a loft conversion in the extended part, or will this be seen as 2 storey then? I suspect so....in which case I could do the extension now and design the roof structure etc so that I can easily do the loft conversion in the near future (with planning permission).

2) Current structure is rather ghastly on the outside - ideally I would like to clad or render the new and old but under PD this would not be permitted it seems (exterior work should match existing exterior). I don't really want to go down the PP route for that If I can help it (due to the time factor). But then I also don't want to clad the new extension in the same ghastky stuff that the existing structure has. Are there any ways around this?

And yes, I will be speaking to an architect and loca council but just wanted to see what people had to say/suggest.

Many thanks,

OB

Doozergirl

4 metres high at ridge immediately means that you're not going to get a loft conversion in it, unless the building is partially below ground level? Building regulations requires minimum 2.2 metre head height at the ridge which leaves you 1.8 metres head height downstairs in a ground level storey. I'm nearly that, and I'm a girl You'll need PP for a taller extension. It's not that bad; you can do all your ground level work and build walls before you get the PP, as long as you're not going higher than PD allows until your PP is through. Most planning officers will tell you if they're going to recommend approval. Your proposition sounds like a formality, tbh.

Recladding the original house falls under PD. As long as the extension and the original house are similar at the end, it will still be PD.

Oranjeboom

Thanks for the response.

Yes, that was indeed my tactic - to start the ground level below ground.;) Floor level would sit at least 90cm below ground.

Ground floor to ceiling = 2.4m
Ceiling/loft floor = 30cm
loft floor to ridge height = 2.2

Speed is of the essence for this extension and that's why I don't want to take the PP route if I can help it. I would be looking to use SIPs for the build, so there would be no time built in to wait for planning to come through.

The house sits on a slight slope, so the front of the extension (front elevation of house) would be deeper than the rear where I am planning to have double doors to the garden. The extension would be for 2 bedrooms and a bathroom so won't be a thoroughfare and I am hoping Building Regs would be okay with steps down into the side extension.

Don't want to dig myself into a hole...:rotfl:

Like I said, I need to speak to an architect and then the council - they may even suggest that PP may not take months to come through.

Didn't know that re-cadding came under PD - thanks!

OB

Doozergirl

The timeline for householders application is only eight weeks.

Digging into ground is expensive, SIPs are also expensive. What's the lead time on the SIPs and who is erecting them for you? I'd be really surprised if you didn't have time.

Does this extension sit lower than the existing house or does the exisiting house sit partially underground? What the planning department consider to be existing ground level is very subjective. Clearly, you don't want to build with SIPs with any part of the walls touching earth and you don't want an enforcement notice.

If time = money then you're potentially only buying away that time with cost.

fluffymuffy

Doozergirl wrote: »

Building regulations requires minimum 2.2 metre head height at the ridge

Minimum room height were removed from the Building Regulations, except for 2m on the stairs.

Have they been put back in now?

Doozergirl

fluffymuffy wrote: »

Minimum room height were removed from the Building Regulations, except for 2m on the stairs.

Have they been put back in now?

I know about 2m head height, was not aware that 2.2m change had been replaced by it, thank you.

In relation to OP, without a large dormer, which is not allowed under PD rights on an extension, and even if the stairs arrive directly under the ridge, ridge height still needs to be considerably higher than 2m for OP to have decent usable space.

Oranjeboom

Doozergirl wrote: »

The timeline for householders application is only eight weeks.

Digging into ground is expensive, SIPs are also expensive. What's the lead time on the SIPs and who is erecting them for you? I'd be really surprised if you didn't have time.

Does this extension sit lower than the existing house or does the exisiting house sit partially underground? What the planning department consider to be existing ground level is very subjective. Clearly, you don't want to build with SIPs with any part of the walls touching earth and you don't want an enforcement notice.

If time = money then you're potentially only buying away that time with cost.

I have other personal reasons which mean I need to have the extension up ASAP, hence the PD route would be favourable and the cost of digging out the 'cellar' would be okay.

My concern with digging down is that we would have to do something to the foundations for the existing house (underpin?). Yes, the current house would sit higher than the new extension.

With the SIPs going below ground level, I was going to have a retaining wall built around the extension, fully drained so that the SIPs would not be touching any earth at all.

I'll be contacting the local planners to see how receptive they are of my plans.

You stated that with PP " The timeline for householders application is only eight weeks." Does that mean they have to commit to a decision within 8wks? If that's the case, then that would be fine with me as the lead in time with SIPs manufacture would be at least 6wks (2wks architect plans/input on top of that too).

Thanks!

OB

Doozergirl

Yes, their deadline is eight weeks. They're public sector, so over-runs are a possibility(!) but when you speak to the planners, they can tell you how busy they are. Yours isn't going to be the most contentious of issues if it's a matter of something that would fall under permitted development but for a slightly higher roofline.