Exempt extension vs building regs?

ChristaG

Hi, I hope someone can be of help.

I am interested in buying a house that has an extension (built in or after 2009) which is exempt because of its surface (less than 40 m2). The extension comprises of a sunroom and a bedroom. The opinion on compliance (submitted by the vendor’s engineer) mentions that all works comply substantially with the Building Regulations of the Building Control Act of 1990. The ceiling height is 2.10m, my own engineer says that the height of 2.10m is not in compliance with current regulations. I googled a bit and I think it should be 2.40m.

My questions are:

1) the extension is exempt because of its surface, but does that mean that it, yes, does, or, no, does not need to have a specific height? If yes, what height?

2) what ceiling height for habitable spaces was regulation in and after 2009? From when until when was this regulation?

Hope my case & questions are clear and that someone can be of help. Thanks!

sydthebeat

https://www.boards.ie/discussion/2058296335/exempt-extension-vs-building-regs

'exempt from planning' does not mean 'exempt from building regulations', therefore a minimum height of 2.4 m should apply to habitable rooms.

however a single storey conservatory extension may be exempt from the building regulations, once it complies with certain conditions:

1. The building shall have a floor area not exceeding 25 square metres (or in the case of a porch, 2 square metres).

2. The building shall have height not exceeding 3 metres, or in the case of a building with a pitched roof, not exceeding 4 metres

The bedroom part however should comply with all building regulations.

is it definitely being sold as a bedroom?

ChristaG

Thanks a lot, Syd, this confirms my idea. It is indeed advertised as a bedroom and also the ‘opinion of compliance’ mentions ‘2 bedrooms’. No. 1 is in the original building, No. 2 is in the extension.

Do you happen to know as from when the height of 2.4 m is a building reg? Would that be 1963, 1990 or later?

FJMC

My understanding is that the height of habitable rooms is only stipulated in Technical Guidnace F Ventilation but it is not considered a critical factor as there are other means of demonstrating that a room is adequately ventilated even if the height of 2.4m was not achieved or not achieved over a required percentage of floor area?

The original engineer may have taken a view that ventilation was adequate even though the height of the room was less than 2.4m or less than the percentage area.

F

sydthebeat

https://www.boards.ie/discussion/comment/120597638#Comment_120597638

the building regulations only came into force on 1st june 1992. Youre think of the planning regs when referencing 1963 (though technically it was 1st oct 1964 for planning regs)

as above, its Part F of the building regs which reference this 2.4m heigh, which deals with ventilation.

interestingly, the requirement for 2.4 was enshrined in 1992 TGD F

However this section was revised in 1997 to refer to a "suggested" height for good design. The suggested height is still 2.4m, but the removal of "should not be less than 2.4m" has left some ambiguity in the regs.

Its a very grey area though. if you want to see just how "grey" have a read of this:

https://www.boards.ie/discussion/2056219830/ceiling-heights

essentially however, its accepted that 2.4m is the standard height for habitable rooms. Current Planning guidelines have this written in as a minimum standard.

However, the certifier is not certifying in accordance with current planning guidelines, they are certifying in accordance with building regulations. if they feel they room "substantially" complies with the building regulations, so be it. Youre engineer is correct to flag this, and ultimate its your choice to accept the opinion of not.

personally, i would qualify my certificate by referring to the diminished height.

ChristaG

Thank you both for your comments, they are highly appreciated. Wish Syd had been the one drawing up the certificate. We have meanwhile withdrawn from this project. It just did not feel good.