Anybody got a walk-out basement?

diarmuid05

Hi Guys,

I'm planning on building a new garage, but my site slopes drastically away from the house. At the moment the back garden is layered into 3 levels.

I was thinking instead of trying to build up a foundation it would make more sense to go down and include a basement that exits onto the lower level with the top level the same as the driveway.

I'd be interested in opinions if this is a good idea or not.
And if it is,
1) What kind of extra costs am i looking at?
2) Would i need planning permission?


Thanks

diarmuid05

Photos of site

Metric Tensor

It can be a really nice feature in my opinion but the water proofing and retaining wall details required add quite a bit more expense than you would expect. The level of water proofing required also depends on the proposed use .... i.e. a library vs. a garage!

Edit to add: You should have planning permission for something like that.

diarmuid05

Thanks for that, I think it's worth investigating further anyway.
So who would I talk to in order to get started and get some plans done, quotes etc

Architect, Engineer, Builder, Local Block-layer?

Metric Tensor

You'll need an engineer to design the reinforced concrete walls required to hold back the ground - so that would be a starting point.

Have you gotten planning permission yet? Some engineers do that sort of work and others don't.

Anyway start with the consultant and don't approach the builder until you have something on paper to work with.

diarmuid05

Metric Tensor wrote: »

You'll need an engineer to design the reinforced concrete walls required to hold back the ground - so that would be a starting point.

Have you gotten planning permission yet? Some engineers do that sort of work and others don't.

Anyway start with the consultant and don't approach the builder until you have something on paper to work with.

No, no planning permission yet, still just an idea in my head.
Would it qualify under any exemption as the footprint would be quite small?

Metric Tensor

Remember by putting a second level in it you are doubling the area. Also your picture seems to suggest it will he beside the house rather than behind it?

That's why I'd say you need planning. Pop up some answers to the questions below and people here will be able to tell you if you need planning permission?

Location of proposed garage - i.e. side, back, front of house, etc.
Total floor area of proposed garage?
Total height of proposed garage and roof type?
Will it be attached or detached from the house?
Remaining garden area after garage is built?
Any other garages or sheds on your site?
Has your house previously been extended, if so what area and did you get planning permission?

If you engage a professional and tell him/her these things they will also let you know if you need planning permission.

diarmuid05

Metric Tensor wrote: »

Remember by putting a second level in it you are doubling the area. Also your picture seems to suggest it will he beside the house rather than behind it?

That's why I'd say you need planning. Pop up some answers to the questions below and people here will be able to tell you if you need planning permission?

Location of proposed garage - i.e. side, back, front of house, etc.
Total floor area of proposed garage?
Total height of proposed garage and roof type?
Will it be attached or detached from the house?
Remaining garden area after garage is built?
Any other garages or sheds on your site?
Has your house previously been extended, if so what area and did you get planning permission?

If you engage a professional and tell him/her these things they will also let you know if you need planning permission.

I didn't realize planning exemption floor area calculation would include basement, would it also have to include attic space??

I'll try to answer the ones i know the answers to at this stage

Location is to the side of house but set back, there is a driveway that circles that side of the house.
Floor area : unknown - open to advice/suggestions depending on planning etc
Total height: unknown - open to advice/suggestions depending on planning etc
Detached from house
1/2 acre site so plenty of garden remaining
Just a timber shed that will be removed
No previous extensions

Appreciate all the help

Metric Tensor

The basement, particularly if it has it's own entrance is another storey - just like the first floor (if you have one) of your house is counted. If you have a fixed staircase to the attic it might be counted. If it doesn't it won't!

You can't build anything above 25 square metres without planning permission and 25 square metres is relatively modest, particularly if you're at a scale where you are thinking about a basement. Planning permission is not an expensive undertaking and provided you are not planning to run some sort of business from your new garage/shed I can't see it being an unreasonable application - it shouldn't be something that should scare you off in my opinion. The basement will be expensive to do correctly - the planning costs will be insignificant in the final sum up of costs!

Angry bird

ground works around your house +/- 1 metre is exempt from planning, so over that needs planning, nevermind the floor area and height restrictions re garage exemptions. It's a good idea in my opinion and metric's advice is solid too.

Gumbo

I would apply for planning to keep it legal.