reason for 7m distance between rear extension and boundary? likelihood of planning permission?

21 Jan 2017
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United Kingdom

I was just wondering if anybody knew the reason why when building a 2 story rear extension there must be 7m between the rear boundary?

We're considering a 5m x 4m 2 story extension to the rear of our 1950's semi, opposite side to our neighbour so will be 2m from boundary with next door. We're on a large corner plot with front door/porch at the side (gable end). Currently the majority of the rear wall is 7.5m from the boundary, we then have a 3m wide utility which protrudes 2m from the rear.. So 5.5m from the rear boundary. This is part of the original house.

To the other side of us there is a road and to the back is the first of semi detatched new builds. The back of us looks to the side of their house but we have 7.5m to the rear fence and then they have approx 3m of garden at the side of their house plus a 3m attatched garage. So there's about 13m between us currently. Our small bedroom and landing window at the back faces theirs and overlooks their garden and conservatory where they spend a lot of time.

If we were to get planning permission we wouldn't be having any windows in the wall that faces/overlooks them so they'd have more privacy, we'd just be closer and only have about 9m between us.

How likely do you think it is that we'd get planning permission for this?

Also, we'd want to have a window on the side of the extension on the 1st floor and bifold doors on the ground floor (side that will be in line with our gable end) then put a window in the gable end to replace the one we'll lose in the small bedroom. The side faces a road but then on the other side of the road is the side of a semi-detatched bungalow. (So the two roads from our view are like an upside down T) On the other side of the bungalows/upside down T are fields and a canal. Our view would mostly be over the roof tops of the bugalows then fields beyond however we would possibly be able to see over the first bungalows gardens if we looked sharply left. But we'd no longer be able to see into the closer gardens at the back of us due to removing windows at the back. The first bungalow/garden is probably about 15m away from us. We both have 6ft fences on the sides fronting the road between us so the groundfloor isnt an issue. We can't see them from our front door and they cant see us from their side windows (frosted kitchen and bathroom). Do you think they'd make us have frosted glass on the upper floor? Obviously we'd really like clear windows as the upper floor as we'd like to be able to see the fields. Not too concerned about the one in the small bedroom but definitely in ours.

I've even been looking at electric tinting glass so I could change it when the planners came round to check but I think it may cost as much as the extension!

Thanks :)
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A site plan is worth 506 words.

And what does your council's planning policy state?
sorry I don't know what a site plan is :)

Nothing that I can see other than it wouldn't be a permitted development and would need planning permission. It's warrington council.

I was just wondering what the reason was as it wouldn't block light or anything.

Forgot to add that at the moment through our back windows we can see into the bedrooms of those behind whose gardens back onto our neighbours and vice versa. So it would give a lot of us more privacy.
The issues tend to be over looking and a domineering effect created by removing the open space between buildings.
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Sorry these are very vague haha but hopefully they make sense :)
The garage and conservatory will be removed. We would no longer be overlooking those to the right and back of us. But would be slightly over looking the bungalows to the left but mostly over their rooftops.
Don't judge me by these photos. They were done quickly on my phone. But is it possible to draw basic plans yourself to get planning permission then ask an architect to do them more detailed ones for buildings?
Don't want to spend £1000 on plans if it could be a waste?
If you're going to do the plans yourself (which is possible) you need to do some reading on your councils' planning policies and the planning portal to find out what they will and won't accept. You don't need tarty CAD software or anything- some graph paper, a sharp pencil, ruler, setsquare etc will be absolutely fine.

Or you can find yourself a drawing technician (architects are expensive beasts) who should be aware of what will and won't fly in your locality- yes it'll cost £100s but not £1000s
I cant see why you could not build a rear extension on that. As its building up to the side of an adjacent property, and not facing the rear of an opposing property, then the common dimensions relating building towards the rear boundary would not normally apply.

However, the pertinant issue would be the amount of infilling that a large extension would create, and any 45 degree angles from the neighbours windows
The extension wouldnt be 4m depth from the rear wall. Replacing the current 2m utility. Then 5m across, so 2m from our attached neighbour and 3.5m from the start of the garden behind us.
Their window directly behind us is their landing and is frosted. We won't be having any windows on this wall.

The attached neighbours closest windows downstairs is her kitchen (no other windows on ground floor) then upstairs bathroom, then landing then one bedroom on the furthest side of the house which would be way off. So I don't think we need to worry about the 45 degree rule do we? We also won't be having any windows on the wall facing her garden.

I had a look on the planning portal yesterday but it seems to only cover permitted developments that don't need planning permission. Since we will be within 7m of the rear boundary (part of the original house already is!) then I think we'd just have to submit and hope.

Is 5x4 considered a large extension? How much do you think it would cost for just the build? I've seen 1500-2000/sqm but that seems to be more southern prices and not sure if single or double story?

Oh that's good, I was planning to download some CAD software but I'd feel much more in my comfort zone with a drawing :)


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