Building control frustrations! - lack of communication & 4.5m first floor to ground

[Great_scot_selfbuild]

Just need to vent a little frustration and see if I’m the only one…

 

I imagine like many professionals, this comes down to personalities and probably workload, but getting hold of my building control inspector (private) to actually speak to is a real challenge if I can’t take a valuable day off work to be on site for the day he visits. He visits, leaves, writes report and often asks for documentation I’ve already submitted, or refers to details that are inaccurate and need correcting.

 

Latest visit he has stated that the first floor height to ground is over 4.5m and so we need a full fire-protected stairwell. This will result in a lot of fire doors.

I previously discussed this with him in person (on an earlier visit when I’d taken a day’s leave to make sure I could speak to him); the ground slopes and the finished house will have decking on 3 sides at floor level, and so all those windows are very comfortably less than 4.5m (this was his words - so in this case it’s a pragmatic first floor to the surface outside the window, rather than ‘ground’, which is below the decking). This leaves two windows at the end where ground is highest and the first floor height to ground I’ve measured to be 4.0m.

 

Now, I’ve read the Part B many times, and it just refers to the ‘first floor’ height which, being as it doesn’t say first floor window, I have taken at it’s word as first floor height to ground. Has anyone experienced or seen it defined as the window to ground rather than floor? (Our FFL to ground is 4m and the window ledge is, from recollection, 550mm above FFL). I’m looking (hoping) for support / examples that it’s FFL to ground. I am prepared to be disappointed however 😕.

 

We’re aiming for a high standard of build, but I’d rather have the choice over which doors to fit rather than have fire doors imposed upon us.

[Andehh]

Fire doors have a reassuring heft and sound deadening benefit as well... Not always a bad thing to have that in a high quality home!! 

[Big Jimbo]

I think the concern must be the distance from the bottom of the window, to something solid below. Whether that is grass, patio, decking, etc. So he may be saying that at present the height does not comply, but it will however once yo fit your decking.

[ToughButterCup]

10 hours ago, Great_scot_selfbuild said:

...

but getting hold of my  [...] to actually speak to is a real challenge

...

 

Irrespective of sector or industry, efficient communication is not valued at best, and ignored at worst.

Trades folk, professionals and customers in our sector all have so many ways of foockingitup: you have my sincere sympathy. Think of it as a rite of passage. A hardening-off process.

 

Thats the best I've got - from someone who spent many years teaching people how to attempt to communicate well. 

Its Friday.  Is that a help?

[ADLIan]

Agree not the clearest advice in Appr Doc B! My view is that it refers to any part of the upper floor being above 4.5m and it’s not related to the floor height. To not fall foul of this requirement means the ceiling of the upper floor should be no more than 4.5m above GL.

 

Next issue is any adjacent decking. This may have to be ignored as height looks to be related to ground level (the decking may be removed at some point in the future!).

 

If you BCO will not offer guidance you may have to submit drawings and await comments.

[Mr Punter]

3 hours ago, ADLIan said:

Agree not the clearest advice in Appr Doc B! My view is that it refers to any part of the upper floor being above 4.5m and it’s not related to the floor height. To not fall foul of this requirement means the ceiling of the upper floor should be no more than 4.5m above GL.

 

So really all normal 2 storey buildings?  Typically outside ground level = 0.00, Ground floor FFL = 0.15, Ground floor ceiling = 2.55, First floor FFL = 2.85, First floor ceiling = 5.25.  I think you may have misinterpreted the guidance.

[kandgmitchell]

A agree Part B isn't always the clearest. However, Diagram 2.1b refers to escape from dwellinghouses with a storey no higher than 4.5m from ground level. The dimension arrows are confusing as they seem to suggest a window cill but that is not the case as other diagrams use the same form of measurement when physical escape from windows is not relevant (eg cavity barriers). It must refer to the floor height.

 

Diagram D6 in Appendix D measures storey height from the upper surface of the floor to external ground level. This reinforces the assumption that "storey height" is measured from floor level not window or ceiling level.

 

The issue for the OP is that the height of the first floor storey is more than 4.5m because storey height is measured to the lowest ground level and so having a storey over 4.5m high triggers the requirement shown in Diagram 2.1c. I would argue therefore any upper floor habitable room requires a protected escape route and building control are correct. It's a pity this wasn't determined at plans stage.

 

Now having started from that position, it's sensible to look at the actual situation. If you have rooms where the ground outside any escape window is less than 4.5m from floor level then realistically they are no worse off than a "normal" two storey house. Others that rely on a decking to reduce that height to 4.5m are different. I think that depends on the decking. If it's substantial structural floor that is perhaps partially supported by the house well that's one thing. If it's a skimpy timber patio deck then that's another. 

 

The OP is going to have to convince BC that the deck is a permanent structure that would just as improbable to remove as digging out the ground outside the compliant windows at a later date would be. 

[Great_scot_selfbuild]

9 hours ago, ToughButterCup said:

Its Friday.  Is that a help?

Yes. This + gin helps on a Friday 😁🤣

[Great_scot_selfbuild]

1 hour ago, kandgmitchell said:

A agree Part B isn't always the clearest. However, Diagram 2.1b refers to escape from dwellinghouses with a storey no higher than 4.5m from ground level. The dimension arrows are confusing as they seem to suggest a window cill but that is not the case as other diagrams use the same form of measurement when physical escape from windows is not relevant (eg cavity barriers). It must refer to the floor height.

Thank you for this. This is exactly what I have been poring over but recognise that just because I want the floor height to be the answer doesn’t mean someone else sees it the same way - you’ve summarised it the same way I (biased) view it, which is reassuring.

 

1 hour ago, kandgmitchell said:

The issue for the OP is that the height of the first floor storey is more than 4.5m because storey height is measured to the lowest ground level and so having a storey over 4.5m high triggers the requirement shown in Diagram 2.1c. I would argue therefore any upper floor habitable room requires a protected escape route and building control are correct. It's a pity this wasn't determined at plans stage.

I did ask about it at plans stage but because of the uneven ground and complexities of the suspended floor structure there were always going to be likely differences between as-designed and as-built. Then the SE added in a beam under the floor that raised it another 150mm and it caused another headache… you get the idea perhaps. (Note to self - I really should do a blog)

 

1 hour ago, kandgmitchell said:

Others that rely on a decking to reduce that height to 4.5m are different. I think that depends on the decking. If it's substantial structural floor that is perhaps partially supported by the house well that's one thing. If it's a skimpy timber patio deck then that's another. 

It’s very robust, SE-designed, steelwork, lots of huge joists, 32mm deck. I do wonder if the BC forgot all about the conversation where he said that the deck level would be the level measured to.

 

@kandgmitchell thanks for your reply.

[Great_scot_selfbuild]

9 hours ago, Big Jimbo said:

So he may be saying that at present the height does not comply, but it will however once yo fit your decking.

I like this positive outlook, and you may be right in the sense that he is very matter-of-fact in the sense that his report simply states what he has seen at the time, as he’s said in the past that if he reflects what is in the design but we don’t build to it, then his report may be misused. I hope to get this clarified.

[Great_scot_selfbuild]

20 hours ago, Andehh said:

Fire doors have a reassuring heft and sound deadening benefit as well... Not always a bad thing to have that in a high quality home!! 

Completely agree, but I’d just rather that it I can choose to do this rather than being made to (for all the doors).

[Mike]

20 hours ago, Great_scot_selfbuild said:

Has anyone experienced or seen it defined as the window to ground rather than floor?

It's defined on page 5, table 0.1 (my bold text):

 

    1(c)(2)(4) Dwellinghouse that does not contain a habitable storey with a floor level a minimum of 4.5m above ground level.

[ETC]

1. Have you got Plan Approval for your house from Building Control? If you have do your drawings show a protected stairway? If they do then you need one - if not you don’t.

2. There are rules for measuring a storey - check out Appendix D.