Extension to already extended house

zoz73

I’m looking to offer on a semi-detached house which already has a single storey rear kitchen/diner extension. I can’t find any planning records online and believe the extension was built some time ago (70s or even prior). It’s an irregular shape and I’d want to square it off plus take some space from the ‘carport’ (essentially garage door, roof but no rear garage wall) to create a utility room and downstairs shower room and smaller, proper garage, leaving 1m rear access walkway alongside the boundary fence - see pic. How much total square footage are you allowed under PD and would it already be used up with this prior extension? Would there be any issues with this proposal? NB the garage is joined to the neighbour’s on the non-attached side.

I’m also considering an additional rear extension to enlarge the living room by 3m but that is optional. Next year I would want to do a loft conversion.

Any advice would be appreciated.

Tooskint

I think that you are only allowed to extend the original house by a percentage and also depends on how close you are to other houses and whether you overlook gardens etc.  Contact your planning department at council for their guidelines.  

zoz73

Potential snag - there’s a drain cover where I’d want to extend - presumably why the original extension is an odd shape. Could I relocate this in order to build here? See pic.

zoz73

Doozergirl

https://www.planningportal.co.uk/info/200130/common_projects/17/extensions

As long as you have permitted development rights and you aren't in greenbelt, then those proposals will fit under PD as long as you stick to height guidelines.  

Guidelines above.  

Depending on which way the drains run, the manhole can be moved outside the extension.  

If it is shared with neighbours, you will
need a Build Over Agreement from your water company as part of the Building Control process.  

zoz73

Thank you - that’s very helpful. 

FreeBear

A car port is usually a flimsy affair that should be regarded as a temporary structure. You are wanting to extend sideways and in effect, build a garage plus utility area - This will require planning approval.

Doozergirl

A single storey side extension, no more than half the width of the house is PD. 

The bit that would require PP is the tiny square of infill where the manhole is as it isn't 'side' or 'rear' of original house.  I'd personally be prepared to take my chances with that.  It's obvious why it wasn't built.    Bit expensive for not much gain, however.  

zoz73

Aaaah yes of course, it's to the side of the previous extension so wouldn't be PD. Doozergirl, what do you mean when you say you'd take your chances? That you think it would be approved? (FYI other houses in the road have built to the side and many have converted their garages to rooms). And do you know the approx cost of moving the manhole? It wouldn't be the end of the world not to square off the kitchen - but would prefer to if i can and if the cost isn't massive. 
The carport has a garage door and roof to the front but no side walls of its own and no rear wall. I think I'd only be wanting to brick up the back wall and put a door in to provide rear access - would this be allowed or if i'm essentially creating a garage, is there more involved for building regs? 

 

Doozergirl

Are you knocking out some of the original side wall and corner of the house there?  

So, making the toilet bigger to be a shower room?  Knocking out the corner to create a half decent utility?  Taking out the corner isn't advisable.  

Moving the manhole, the BOA costs about £600.  If you're in the ground then budget maybe £1000-1500 for extra ground works. The big cost is having to re-roof the kitchen extension.  The extra cost of moving the manhole at the time would have been negligible compared to the cost of the extension.  

Now, it's going to cost thousands for an extra square metre.   

There is another manhole in the garage - is that connected to the first one?  Is the first one connected to the neighbours? Maybe stuff could be diverted over there if they're on the same run and it doesn't affect the neighbours.  

How much are you budgeting for this work? 

Doozergirl

In honesty, if you are considering a rear extension, I'd just build it bigger. 

The current loo was the kitchen originally.  If you don't use it as a hallway and create the open plan kitchen/diner/living room that everyone wants then the old kitchen can be split into a loo and utility.