Jump to content

Egress windows


Dee

Recommended Posts

Can someone tell me how to measure the opening of a first floor window to establish if it passes building regs for fire escape.

I'm in dispute with council !!!

 

20230511_140438.jpg

Link to comment
Share on other sites

This is from a 2010 doc from Lancs Bldg Control (first hit I found - not aware if it has been superceded. Looks about right for what I remember of last time I had to 'prove' one:

 

"Achieving the requirement. The window should have an unobstructed clear openable area that is at least 0.33m2 and have no clear dimension less than 450mm high and 450mm wide (the route through the window may be at an angle rather than straight through), appropriate escape catches and hinges must be fitted to ensure this clear opening is achieved."

 

We had one queried some years ago because the reflex hinges, like yours, brought the 'hinge side' of the opening light into the aperture. We were able to buy alternative hinges (the exact operation of which I cannot remember) which allowed one to push the window over (to the far right in your photo above) 'in extremis' to widen the aperture. (I hope I have not made myself abundantly unclear!)

 

Have they given you details of their objection?

Edited by Redbeard
Request for BC details of objection
  • Thanks 1
Link to comment
Share on other sites

That's still the current guidance, see Paragraph 2.10 of Approved Document B Fire Safety - Volume 1 Dwellings 2019 (inc 2022 ammd's). There is one extra caveat - the cill height should be no more than 1100mm off the floor.

 

Those hinges shown often cause a problem as the casement then intrudes onto the clear opening, as Redbeard says "other hinges are available"......

  • Thanks 1
Link to comment
Share on other sites

Thanks @kandgmitchell. For clarification the 'other hinges' we got were still 'Reflex'-type - they look the same as those in the pic, but the bit on the RHS, which is I think 'captive' in your pic, could be made to slide across to the extreme R to 'optimise the orifice'.

  • Thanks 1
Link to comment
Share on other sites

What’s the issue?

 

You need a 450mm x 750mm (to get the 0.33m2 requirement) clear opening located between 800mm and 1100mm above FFL.

 

If the hinge is an issue by reducing the clear opening just get the hinge moved to give you the clear opening. It’s very easy to do and takes a few minutes to do. Problem solved!

 

 

  • Thanks 2
Link to comment
Share on other sites

Hi,

The issue is thar building control dispute my measurements on two upstairs windows. How I measured then is the issue. The windows couldn't open wider if I tried. The opening is 550+ however its measured. 

How do I move the hinge ?

Link to comment
Share on other sites

If its 550mm to the edge of your square it should be OK. 

 

Sometimes they measure to the handle if they think that reduces the clear opening width.

Edited by Temp
Link to comment
Share on other sites

1 minute ago, Dave Jones said:

those are not fire hinges. just buy a set and the window will fully open.

 

The first picture shows the window opened to a right angle. The second picture looks there is enough width. The square is going onto the bottom of the sash frame, but:

  1. looks like it only goes on by 10mm and the 460mm mark looks to be fairly inside of the mullion -> at least 450mm
  2. Why not have a path that uses the extra width of the glass recess as long as that is of suitable height and you can reach an angle that clears the sash's style
Link to comment
Share on other sites

3 minutes ago, Dave Jones said:

your not measuring it right. from the outside of the handle parallel to the wall into which the window is fitted. Not at that angle.

 

Doesn't look wide enough, had to use a flying mulion on one of ours (1100 width).

 

Part B does allow it to be at an angle:

image.png.719d703132c1f56a811208445267a871.png

Link to comment
Share on other sites

2 hours ago, Dave Jones said:

your not measuring it right. from the outside of the handle parallel to the wall into which the window is fitted. Not at that angle.

 

Doesn't look wide enough, had to use a flying mulion on one of ours (1100 width).

 

image.thumb.png.ad4fce261125e389b3553cb019b1e0b3.png

Nothing wrong with it. You need a 450mmx750mm hole to get through. If you’ve got that you should be fine. Cut out a piece of cardboard 450x750 - if that can get through it should be ok.

 

  • Thanks 1
Link to comment
Share on other sites

Certainly looks OK.

 

Standard hinges open to about 85 degrees. Egress hinges normally open to a true 90 degrees. I'm wondering if the BCO thinks 90 degree hinges are mandatory for some reason?

 

 

Link to comment
Share on other sites

Co-incidentally I had this very conversation yesterday with the BCO who visited our site. His thing to always check is the 1.1m height. He said so many builds fall foul of this. As soon as he left we went straight up to measure it as we’d added a kerb for the Velux windows for the standing seam roof. We’re just under but with the FFL we’ll be well under. 

  • Like 1
Link to comment
Share on other sites

3 hours ago, Kelvin said:

Co-incidentally I had this very conversation yesterday with the BCO who visited our site. His thing to always check is the 1.1m height. He said so many builds fall foul of this. As soon as he left we went straight up to measure it as we’d added a kerb for the Velux windows for the standing seam roof. We’re just under but with the FFL we’ll be well under. 

 

he's right ,1100mm doesn't work brick so brickies have always used 15 courses which is 25mm too high before a window board is added. Use 14 courses and it allows 50mm for window board.

  • Like 1
Link to comment
Share on other sites

14 hours ago, Dave Jones said:

 

he's right ,1100mm doesn't work brick so brickies have always used 15 courses which is 25mm too high before a window board is added. Use 14 courses and it allows 50mm for window board.

This isn't a newbuild so that might not apply, they're replacement windows. Don't understand why he's being such a douch!

Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
×
×
  • Create New...