Fire Escape Velux Window

professorA

Hi All,

I have an issue with a fire escape velux window.
The Homebond manual (p388) states that the
bottom of the velux should be a maximum of 1700mm
from the roof eaves. It also states that the window
opening internally should be 600mm-1100mm above
FFL.

I have attached an image of my problem, its a 28 degree
roof. If i place the velux 600mm above FFL it will be over
2 metres from roof eaves. If i do it the way it is shown,
1700mm from roof eaves, the bottom of the window is well
below 600mm from FFL. Both do not meet the regs.

Has anybody come across an issue like this before? Any
help would be greatly appreciated.

Thanks!

sydthebeat

your roof pitch is incredibly shallow for a 'room in roof' and probably doesnt comply with a few regulations... so the best thing to do is to try to make the best of the situation... which it looks like you are doing and fair play.

The 1.7 reg comes from the theory that someone could hang from the bottom of the roof light and slide gently to the gutter.

The 600 reg comes from the bottom being (a) a prevention from falling out and (b) for safety from children climbing.

Personally i think the 600mm reg is the more important here... to prevent children from climbing out and to prevent someone falling out.

Remember to use a top pivot rooflight, and that the area under the rooflights should be clear from anything dangerous to fall onto.

professorA

Thanks sydthebeat.

I know the roof pitch is extremely low. I was given the plans which
were drawn by someone else. Im doing the construction drawings.
FI came back to say the house needed to be lowered so the roof was reduced from 35 degrees to 28 degrees.

I do think the 600mm for FFL is the best option to go for, just wondering will there be an issue with the non compliance with the 1700mm from eaves reg? :eek:

muffler

professorA wrote: »

Thanks sydthebeat.

I know the roof pitch is extremely low. I was given the plans which
were drawn by someone else. Im doing the construction drawings.
FI came back to say the house needed to be lowered so the roof was reduced from 35 degrees to 28 degrees.

I do think the 600mm for FFL is the best option to go for, just wondering will there be an issue with the non compliance with the 1700mm from eaves reg? :eek:

If this is still on the drawing board so to speak it looks like you will have to abandon the idea of having habitable rooms in the attic space.

sydthebeat

professorA wrote: »

Thanks sydthebeat.

I know the roof pitch is extremely low. I was given the plans which
were drawn by someone else. Im doing the construction drawings.
FI came back to say the house needed to be lowered so the roof was reduced from 35 degrees to 28 degrees.

I do think the 600mm for FFL is the best option to go for, just wondering will there be an issue with the non compliance with the 1700mm from eaves reg? :eek:

oh dear.

have you notified the clients of the non compliance of the attic space with building regulations?

as regards the windows, those regulations are for escape from habitable bedrooms... so as to whether theres an issue or not witnh the 1700, i think there would be a much greater issue with the use of the attic as a bedroom. who will be signing this off?

Quazzie

Would that velux even open? I

sydthebeat

Quazzie wrote: »

Would that velux even open? I

good question....

velux manual states a GPL can be installed betwen 20 and 50 degs

Poor Uncle Tom

If it's still at design stage consider a dormer window in order to comply.

Mellor

As mentioned, the 600 dimension is more critical.
The 1700 comes from crossing the roof. Its worth mentioning, as the pitch decreases, the sill to eaves dimension becomes less critical.

Example:
At 45 degrees, you need to be able to safely hang from the sill to the gutter.
At 15 degrees, hanging isn't as much an issue as the roof can be crossed on foot.

28 degrees is in a middle ground somewhere.

In order to make it exactly as prescribed in TGD B, you need to put in a dormer, 1700 from the eaves with 265mm upstand externally to achieve the 600mm internally.

Poor Uncle Tom

Mellor wrote: »

In order to make it exactly as prescribed in TGD B, you need to put in a dormer, 1700 from the eaves with 265mm upstand externally to achieve the 600mm internally.

While that option is there, the velux route is not acceptable, for signing off purposes why compromise the regulations when you don't need to, imo.

professorA

Thanks for the replies guys, dont think we will be going down the dormer window route. Therefore habitable accommodation will be scrapped!

Thanks again!

JackPerry

Both the Home Bond manual and the Technical Guidance Documents refer to the 1.7m dimension as outlined in the first post.However neither of these documents is actually the Building Regulations. The measures outlined in the TGD documents are deeped to comply with the Building Regulations. However it could probably be argued that if a detail was not exactly as per the TGD this does not necessarily mean non compliance with the Building regulations.

JackPerry

Should have written "deemed to comply" in previous post.