Converting an attic conversion

The previous owner of our house converted the attic around ten years ago. They appear to have used it as some sort of studio, but we just use it for storage. We are now considering re-converting the space to suit our needs ie put a bedroom with an ensuite up there.
It's my understanding that it can't be defined as "habitable space" as the ceiling is slightly too low... but there is ample room, it has stairway access, it's piped for water and heating, and it's double-glazed.
I can see cost estimations for attic conversions in other threads. What I'm wondering is what sort of price might we be looking at if the "construction" part of an attic conversion is already done? Any ideas out there as to approximately how much of a percentage of the full cost might this be?

Although it may not be considered "habitable" in the general sense of the word, as it was used as a studio it is obviously insulated with the external walls and the roof slabbed and plastered. There's obviously electrical up there already too.

After that what is left...a partition for the bathroom, a bathroom suite a few coats of paint...You could do all that for less than €2000.

You may want to provide a roof light for the bathroom...or not...

Just be careful though, if it's not habitable you don't have planning for it. If you don't have planning for it and a fire starts up there and brings the house down...your insurance won't cover you.

selfbuild09 said:

Just be careful though, if it's not habitable you don't have planning for it. If you don't have planning for it and a fire starts up there and brings the house down...your insurance won't cover you.

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Never heard of that. Has this been tested in any recent cases before the courts? (Not doubting you. I'm sure it is a point of insurance many will not be familiar with.)

If it is based purely on whether planning was granted or not, this would include thousands of house extensions as permission is only required when the floor area exceeds 40 sq m (for the rear of a house).

My architect pointed it out when we were drawing up my house. The original plan was to build a bungalow and convert upstairs later...on the QT. He said that if a fire ever occurred and that if the source of the fire was traced back to the attic, i.e a faulty electrical device, we'd be in big trouble.

I suppose it makes sense. The insurance co would have based their quote on the original bungalow and not upstairs....grey area though.

As I understand it, the legislation is part of the Building Regulations rather than planning.

For Part F (Ventilation), there is a requirement for a room to be defined as a habitable room. Specifically, the regulation is that the area of the room at a height of 1.5 metres must be at least 50% of the area at a height of 2.4 metres.

If you converted and remained with your existing insure you just disclose it and its fine. Also theres no questions on a proposal form that states "is your house modified"!! Should be no problem with the insurance. Never seen it in a policy wording either!