What is the loft conversion min height under regs?

18 Apr 2007
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United Kingdom

Can anyone tell me what the minimum height is for a loft conversion is under building regs?

I have looked this up on net without any defining measurement.

I had a survey visit completed recently by a company & they say building regs is 2.4mm min height & to complete a conversion they would have to lower my ceilings 2 inches.

I got about 7ft 10 ins from bottom joist to top of apex. Some other loft conversions website say the min height ranges from 2.2m to 2.4m?

What is it? Anyone know what it actually is?
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Don't use this company as they don't seem to know much about building regs.

There is no regulation height for a room under the building regs

It comes down to what is practical, and in most cases the height of a standard door lining (2m) is probably the minimum acceptable ceiling height

But low ceilings make for pokey rooms, so probably for young kids only?

Remember that you will most likley need a new floor and joists, and so the new floor surface will be higher than the existing ceiling joists by about 120mm

Dormer windows can help with getting a bit more height
Cheers many thanks for this.

I mean my loft is about 2 inches shorter in height then my normal bedroom ceiling height. I'd have to be 7ft tall to have a problem even with the joist in the loft raised.

Decided to put it on ice to later in 2009, so can gather some more information etc.
If the project requires RSJ's at floor and on ceiling you could loose 500mm of space so it would be prudent to get some engineering / design to confirm usable height after method of flooring and ceiling structure and support agreed.
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If the project requires RSJ's at floor and on ceiling you could loose 500mm of space ...
Doubt it! That would only be as a result of an SE not thinking about what he was doing...

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