How to ? create open space on top of a bay window roof

[trevorbayliss]

The photo is of a top floor flat and i would like to knock out the windows and lower wall and install some french doors which would then open out onto the roof of a bay window.

Next door has done this on his top floor flat, but i havent been able to go and have a look.

Does anyone have any links to how this job can be done ? How do you water proof the exterior floor area ? I may need to get some help, but i think i can do this type of work.

Also can you see the damp on the chimney in the room ? Any ideas on what may be causing this. The flat is heated so not cold. Is it the flashings ?

 

[Tigercubrider]

Who owns the freehold?
There is bound to be some type of issue if the "floor" that you are talking about is actually someone else's roof.
What you call a bay window looks to me like a dormer? There may be structural issues in removing it?

It's not clear to me whether you want to bring the window inwards, and use the current carpeted floor as outside space? Or replace the existing windows with doors and be able to walk outside onto a flat roof?

 

[trevorbayliss]

The flat is a freehold, so i will own it.

Yes i could bring the door back into the room, so creating more outside space. I think that will happen to some extent.

The bay is a big structure, which you cannot see.

Just wondered how you make a new floor and water proof it, using a tanking system and not concrete.

The cupboard on the left allows you to crawl round to the front and you can sit on top of the bay. It is still under some roof covering, but it cold and exposed as not heated.

Its a bit complicated to fully explain.

 

[Tigercubrider]

A plan would help? You don't (presumably) own anything outside the flat.
I still don't understand whether the aim is to-
Bring the window backwards, using the current floor as outside space
Replace the windows with a door, opening it but not going outside (Juliet balcony/railings)
Replace the windows with a door and walk on a roof level with your floor

 

[trevorbayliss]

I am not sure if i own the roof. I will need to ask, but the building will pay for repairs to the roof as a whole. We all pay £700 per yr for repairs and insurance. Mine will be the top one, so under the roof.

1) I think the wall will come back a bit, so using some of the internal space. Not decided yet on the amount.

2) The windows will come out and a french door goes in.

3) The door will open onto what is some internal floor space now, but also the top of the bay which is the other side of the current window/wall.

This photo is the external one and shows the bay. The bay does come up quite high. I think it is level with the bottom of the windows line. I don't mean the floor, but the bay walls. So there is a natural protection there and all i will need to do is add some type of balustrade on top.

Any ideas on tanking ?

 

[Captain Nemesis]

Ask these people what they did?

 

[big-all]

if its a raised platform[ above 300mm ground level] and an overlooked position
you will need planning permission which will often be impossible to get through neighbour complaints

 

[Mottie]

The flat is a freehold, so i will own it.

I don’t understand how someone in a top floor flat can own the freehold. Do you mean you own a share of the freehold or do you own the whole building and the ground it sits on as the answer to that might complicate the issues regardless of the actual building work.

 

[Captain Nemesis]

if its a raised platform[ above 300mm ground level] and an overlooked position
you will need planning permission which will often be impossible to get through neighbour complaints

Im sure that at some time in the past Ive seen flats and other buildings with balconies at the front.

 

[trevorbayliss]

Does anyone have a link to these types of projects. That is what i am after. Surely there is something on the internet about how to do this type of job.

Yes i will need planning, the neighbour has done it. I hope to speak to them eventually.

Freehold is for my flat and part of the building. Thete is a covenant to sign on ownership tying you into certain details and restrictions. Many flats in this area use freeholds rather than lease.

 

[trevorbayliss]

Update. I have some more photos. Pretty sure i can do this work, but i think i will need Planning Permission.

Here is a pic showing the dormer window from inside the lounge area. The whole window down to the floor level will come out to be replaced with french doors. The external bay wall is about 10cm below the window cill level.

There is a pic behind the window wall which shows what it looks like outside. This is actually covered by a wood deck covered with lead i think. But you can see where i could fix joist hangers and run new joisting to take a new floor.

There is also a pic of the neighbours bay which have converted, plus some external photos.

What do people think ?

I feel pretty confident i can sort this out. I think a GRP system is going to be the best solution to make the floor water proof.

 

[Captain Nemesis]

GRP can be verynoisy