What is the measurement for the Building Safety Act 2022

[David Allen MISVA]

I have been asked to provide the measurement of a Georgian Town House in relation to the Building Safety Act.  The client is buying a basement flat and his solicitor has requested the dimension.  The act states that “The height of a building is to be measured from ground level to the finished surface of the floor of the top storey of the building”  So from that I take it to mean from the external pavement level, not from the internal ground floor level. However, my colleague has been told by Building Regulations inspectors that the dimension should be from the ground level of the front lightwell, which puts the dimension above the 11m.  You could further complicate it because at the rear there is a sub-basement level!

Should the dimension be from front ground level or lightwell level?

[Paul R E Dyer FISVA]

Hi David I think this may help

From the Building Safety Act 2022

 

118Section 117: height of buildings and number of storeys

(1)This section applies for the purpose of section 117.

(2)The height of a building is to be measured from ground level to the finished surface of the floor of the top storey of the building (ignoring any storey which is a roof-top machinery or plant area or consists exclusively of machinery or plant rooms).

(3)When determining the number of storeys in a building—

(a)any storey below ground level is to be disregarded;

(b)any mezzanine floor is to be regarded as a storey if its internal floor area is at least half of the internal floor area of the largest storey in the building which is not below ground level.

(4)In subsection (2) “ground level”, in relation to a building, means—

(a)the level of the surface of the ground immediately adjacent to the building, or

(b)where the level of the surface of the ground on which the building is situated is not uniform, the level of the lowest part of the surface of the ground immediately adjacent to it.

(5)For the purposes of subsection (3) a storey is “below ground level” if any part of the finished surface of the ceiling of the storey is below the level of the surface of the ground immediately adjacent to that part of the building.

 

So from this it appears to be the bottom of the lightwell as far I read it.

[Paul Bayliss FISVA]

Paul Bayliss MRICS, C.Build E MCABE, FISVA

Chartered Building Surveyor and Chartered Building Engineer.

Dear David

I have followed the developments of this legislation  via the various journals published by CABE, whom as Building Engineers and fire risk assessors, ( you might already know)  have been influential in this area. My understanding of the culture of the legislation is to adopt a sense of pragmatism, so for me the dimension is taken from the lowest external ground level. That seems eminently practical and logical to me, given the  similar approach taken when applying the guidance under Approved Document Part B. Risk is accepted, but guidance presumes a practical application to mitigate.

Not withstanding Pauls very helpful and incisive contribution, I can see a barrister arguing that a roof light / roof well is in fact a “ceiling” where as to most Surveyors, I would argue that it is or only ever would be a part of the “roof” construction to that element. So the light well is subterranean and thus discounted. I may not have explained that point particularly clearly?  apologies.

Ultimately you go with what you are most comfortable with of course. Like all new legislation its interpretations  will be challenged in years to come, so we can only wait and see.

In good faith I hope that might assist? Just a view nothing more.

Kind Regards

Paul.

 

 

 

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