Attic conversion - is there a minimum roof height required?

Kashkai

I'm in the process of getting the ball rolling on renovation works on my bungalow. One of the bedrooms is quite small (10ft x 8ft) and while it currently suffices as a nursery, it will be practically useless (space wise) once the baby grows up. I was thinking that if I converted the attic space above this room and used the existing bedroom to house the stairway up to the attic and perhaps wardrobe space and then put the new bedroom space upstairs with perhaps a shower as well, this would give more usable living space to one of our kids as they grow older.

However, is there a minimum height necessary in an attic space to sucessfully convert it without having to walk in a crouch each time you go up there? At the moment, there's about 7 feet of height from the joists to the apex of the roof but once rsj's and a new floor/ceiling go in, will there be insufficient height for anyone to use bar a child? I've seen attic conversions in houses where I never thought they'd end up with any kind of usable space but they turned out quite succesful.

I just want to get some opinions before I ask a builder to quote - a good builder might tell me its a waste of time but another will do the work, take the money and leave me with a claustrophic space.

RKQ

2.4m is the recommended minimum height for a Habital room.

Why not discuss your ideas with a local Arch Tech with full PI insurance. A professional could give you all the answers you require - its difficult to say without seeing the structure.

Poor Uncle Tom

Page 8 would seem to be what you are looking for....

http://www.environ.ie/en/Publications/DevelopmentandHousing/BuildingStandards/FileDownLoad,1647,en.pdf

Remember, these are Technical Guidance Documents which are suggested and not mandatory but they are designed to fall in line with the Building Regulations which are mandatory.

Poor Uncle Tom

RKQ wrote: »

2.4m is the recommended minimum height for a Habital room.

Why not discuss your ideas with a local Arch Tech with full PI insurance. A professional could give you all the answers you require - its difficult to say without seeing the structure.

Technically this is not correct as the height of a habitable room may go under 2.4m as seen in all habitable dormer type rooms.

RKQ

IMO 2.4m is the recommended minimum height for a Habital room, and is consistent with good room design, the use of standard materials and good building practice. As per Diagram 5, Par 1.13, Page 8 TGD F 2002. This document will be replaced early 2010 (maybe in the next few days).

1.13 Ceiling height is one of a number of factors which affect ventilation of habitable rooms. The suggested dimensions in Diagram 5 are consistent
with good room design, the use of standard materials and good building practice.

This is my personal opinion of course and others may disagree.

mad m

I agree with you RKQ as the planning authority(Dublin), shot me down when I had a height of 2.1m.

Poor Uncle Tom

You misunderstood me, your comment was "2.4m is the recommended minimum height for a Habitable room"
If this comment is to be taken at face value then no point of the ceiling of a habitable room can go below 2.4m from the floor, thus eliminating dormer style rooms as being habitable rooms.

The link you show, RKQ, is the same as I provided 2 posts before.

RKQ

The diagram in the pdf I attached clearly shows how to assess Dormer roof heights. (The isometric triangular sketch). This pdf page is specific to the question, to help the OP.

I also wrote " A professional could give you all the answers you require - its difficult to say without seeing the structure". This was stated to specifically avoid any misunderstanding.

I hope this has helped to clarified the issue for the OP.

Mellor

The quick answer is;

If you only have 7 foot (c.2100) to the apex, then it is unlikely that you can successfully convert it with out raising the roof line