Ceiling Heights

IMO, 2.4m is very much on the low ide of what anyone should be designing to. Anything less than that feels uncomfortably low.

YouWantWhat wrote: »

You also should not be making such statements unless you can back it up with authority and fact. I had this confirmed by the Building Control Authority, who are the authority for the Building Regulations in this country. I would take their recommendation over yours.

One small fact, there's more than one Building Control Authority in this country, Each local authority has a Building Control Authority.

Some building control authorities have been known to interperate Technical Guidance Documents incorrectly so just because they said it, doesn't mean its definitive. Confirmation from the Building Standards Section of Department of Environment, Community and Local Government would be far better. However the most definitive guidance of what the law is, is via a court ruling.

YouWantWhat wrote: »

I would refer you to my previous post, and I reiterate its content. To refer to the Chief Building Control Officer at Waterford County Council as a "a staff member of the Building Control Authority" is a bit derogatory.

The TGD's are only guidelines. If you read the introduction page in any of the TGD's it states that "the adoption of an approach other than that outlined in the guidance is NOT precluded".

Take part B for instance, perhaps you've heard of fire engineering, that's a way of complying with the building regulations without necessarily referring or conforming to Part B. The same applies to every other section.

Well perhaps if you stated that it was the C.B.C.O of WCC it would have handy?however he / she is still a staff member?

In past dealings with Building Control Authorities, they can still get it wrong sometimes.

TGDs are guidelines as so to be in compliance with the building regs.
You mantioned the recommendation in the building regs is 2.4m, so you have read that and didn't like the sound of it?

Also what is the background to your question so that we can see the angle that you are looking from?

we are not talking about Part B though are we?

In fairness, reading back over the thread, you don't appear happy at all that fellow boardsies have a different opinion on this topic but hey that may just b me.

YouWantWhat wrote: »

When I started the thread I was looking for facts, not peoples opinions or interpretations. Since then I contacted the BCO myself and got the facts from them. But people on this forum seem to know better!

You mentioned fire engineering as a different interpretation of Part B did you not?

the people on this forum were imparting their knowledge. If you didn't want their answers, why post in the first place?
So IMO what I can get from your replies is that you don't want to share the background to your question, you have decided you don't want to comply with building regs and there has possibly been a mistake with a design / building.

Regarding building control, you have heard of Priory Hall up here in Dublin haven't you?

YouWantWhat wrote: »

When I started the thread I was looking for facts, not peoples opinions or interpretations. Since then I contacted the BCO myself and got the facts from them. But people on this forum seem to know better!

You got The Building Control Officer's interpretation of the Technical Guidance Document.Did the Building Control Officer put it in writing?

YouWantWhat wrote: »

Thats a bit of an arrogant reply............................You also should not be making such statements unless you can back it up with authority and fact. I had this confirmed by the Building Control Authority, who are the authority for the Building Regulations in this country. I would take their recommendation over yours.

YouWantWhat wrote: »

Whatever.

Keep up the attitude and I will remove your posting privileges.


And I dont particularly like this comment

YouWantWhat wrote: »

When I started the thread I was looking for facts, not peoples opinions or interpretations. Since then I contacted the BCO myself and got the facts from them. But people on this forum seem to know better!

People here were good enough to answer your questions but there appears to be double standards here when you yourself said "You also should not be making such statements unless you can back it up with authority and fact" I see no written proof of fact from your local BCO.

Part F deals with ventilation. The diagram that refers to room height only get one reference in text;

Ceiling height is one of a number of
factors which affects ventilation of habitable
rooms. The suggested dimensions in
Diagram 3 are consistent with good room
design, the use of standard materials and
good building practice.

As mentioned above the TGD are not exclusive legal documents. What I mean by this is if an alternate engineering solution can be proved that complies with the purpose of the regulation then it is acceptable. In this case a solution may be to design the room with Non-standard materials or fantastic building practice. A more logical approach is to consider why 2.4m is defined. It is solely with regard to ventilation thus if one could prove the room has sufficient ventilation with a lower ceiling height the regulation is satisfied. See BS 5925 for more info.

Unfortunately whether a local authority architect or planner can understand the calculation or the rational used above is open for discussion.

If anybody believes that you can design structural members by just using Part A (ie. not using eurocodes / BS5950 / BS8110) or make a complex building fire safe just using Part B please leave you name below so I can be sure I never work with you.

Mellor wrote: »

Of course you can use just part B.

No you can't. Most "complex" buildings need to be at least checked under a part of BS 5588, even the smoke detection for a dwelling house must be checked using a separate standard, can't remember it off hand.

"The TGDs indicate (not suggest) a method of complying with the law."

In relation to your earlier comments you're also wrong the are guidance and not enforceable to the letter without consideration. More specifically the title of the diagram is; "Diagram 3: Suggested height of habitable rooms." therefore the term "suggest" is correct.

I know this from some expert witness work in legal cases where this issue was resolved.


The issue with room heights is a lack of understanding of the purpose of a 2.4m height and lack of clarity on the issue from the Department. What really needs to be considered is what is a habitable room?

2.4m min is suggested good habitable room design - paraphrased. But as this statement resides in the guidance for ventilation; proof that a room with a lower ceiling also provides sufficient ventilation (once the height does not impinge on other areas of compliance) is sufficient.

All that said all rooms should be 2.44m min. in my opinion in keeping with the 8ft ceilings of our heritage.

So can we agree the 2.4m is solely considered necessary to provided proper ventilation? (only appears in part F)
Most likely the figure is convenient and works well with standard room sizes for the purpose of ventilation, agreed?

This requirement is somewhat questionable; ventilation rates are based on building volume; calculated more accurately in reference documentation {CIBSE Guide A or BS 5925}

There is one other issue to be considered and that is convection of heat within the building itself. Again 2.4m is convenient but by no means a steadfast rule for provision of same.

Another issue worth analysing might be the testing spec for fire protection of the roof (ie. lower = closer to fire) - though I doubt this should be a factor.

Essentially I suggest if one wants to stray from the norm in this instance one must analyse the situation in detail to ensure the building works.

In my opinion only providing height for ventilation is incorrect a minimum acceptable room height for new buildings should be defined for aesthetic and practicality reasons.

RockyTwoArms wrote: »

No you can't. Most "complex" buildings need to be at least checked under a part of BS 5588, even the smoke detection for a dwelling house must be checked using a separate standard, can't remember it off hand.

I clearly said that is doesn't work in all cases. But that it is possible. Please don't edits posts to misrepresent any users.
The relevant BS codes that you must comply with are refered to as part of TGD B, so i'd still include inherent to the TGD as a whole.

"The TGDs indicate (not suggest) a method of complying with the law."

In relation to your earlier comments you're also wrong the are guidance and not enforceable to the letter without consideration. More specifically the title of the diagram is; "Diagram 3: Suggested height of habitable rooms." therefore the term "suggest" is correct.

I said that the building regs were law, not that the TGDs were law. Key differance.
And I said that the TGDs as a indicate various methods that may be used - not the ones that must be used. You are of course free to go with a different method. But if you go by a method indicated, then you should meet, or rather aim to meet, the minimun levels suggested.

2.4m min is suggested good habitable room design - paraphrased. But as this statement resides in the guidance for ventilation; proof that a room with a lower ceiling also provides sufficient ventilation (once the height does not impinge on other areas of compliance) is sufficient.

I agree if you could prove it then its sufficient. However, I'm not sure how one would go about proving it.
Say for example, that due to a issue during construction, the ceiling hieght was 2300 (originally designed to be 2440mm). I'd be happy to sign a document to say that it substansially complies with the regulation as long as the ventilation sould be meaured or calculated as being not significantly different.
However, because the TGDs note the dimension of 2400 as being the minimum to achieve ventilation I wouldn't be happy with proceeding with a ceiling designed to be 2300mm.
Do you see my point? I see a key difference between a ceiling ending up slightly short when finished and one that was never designed to meet the TGDs

All that said all rooms should be 2.44m min. in my opinion in keeping with the 8ft ceilings of our heritage.

Agree. I do a lot of work heritage work and I really feel that homes suffer architecturally due to the gradual drop in ceiling height.

RockyTwoArms wrote: »

So can we agree the 2.4m is solely considered necessary to provided proper ventilation? (only appears in part F)
Most likely the figure is convenient and works well with standard room sizes for the purpose of ventilation, agreed?

THats correct, there is a part B height, buts its only on escape routes
I was never happy with it appearing solely in part F, but it was the best of TGDs gave us.

Essentially I suggest if one wants to stray from the norm in this instance one must analyse the situation in detail to ensure the building works.

Agree. Nobody was attempting to say that is was impossible to stray from the TGDs. But rather in straight forward situations with one parameter like minimum heights, widths etc that its unwise due to the difficultly of backing it up on paper. Dynamic regualtions based on a number of parameters tend to operate outside the TGDs easier due to the sheer number of options (eg fire engineered solutions)

In my opinion only providing height for ventilation is incorrect a minimum acceptable room height for new buildings should be defined for aesthetic and practicality reasons.

Ceilign heights should meet the minimum for aesthetic and practicality reasons from a designers point of view. However, these areas are outside the scope of the building regs and the TGDs. If we were to make a TGD for aesthetics there would be a lot of changes to some dwellings built in the last 20 years.