Joining rear extension to neighbours?

[extend_my_house]

We have a 1960's semi-detached house - same design as many up and down the country.

Both us and the neighbours have a rear extension, but in a different orientation - leaving a bit of a void space between the 2 extensions - approx 4mx 4m - shown in red on the attached diagram.

 

We would like to extend our kitchen into this space - to the same depth as the neighbours extension and ideally joining on to it (assuming they were in agreement).

 

Is this possible?

 

From a planning POV?

If we didn't have the extensions then the 2 houses would be joined anyway.

 

From a practical point of view?

Is it posible to join 2 flat roofs together?

 

[joe90]

How well do you get on with your neighbour?

[extend_my_house]

Fairly well and I believe they would be agreeable based on conversations we have had in the past so long as there was no down-side for them.

[joe90]

That’s a good start.

13 minutes ago, extend_my_house said:

Is it posible to join 2 flat roofs together?

Yes, what is the roofs comprised of? (Felt, GRP, membrane)

[extend_my_house]

Ours is green mineral felt and theirs seems to be normal black felt.

The is a height difference of about 800mm between the 2 extensions - their is higher - so I would like the extension into the "void" to be the same height as theirs and then step-down to ours.

[Redbeard]

I think if it were me I might be getting ball-park prices from local GRP/EPDM flat roofing contractors with a view to offering the neighbour a 'sweetener' which could lie somewhere between a percentage of the estimated cost of re-roofing their exg extension on the exg deck and the full cost of re-building their roof to become a Warm Roof (like yours might become, clearances permitting - I'm thinking windows, flues, whatever).

[MAB]

In England or Wales you need a 'Party Wall Agreement' between you and your neighbour but not sure if anything similar in Scotland?

Party walls and building work:-

https://www.gov.uk/party-walls-building-works