Advertisement
If you have a new account but are having problems posting or verifying your account, please email Niamh on [email protected] for help. Thanks :)
New AMA with a US police officer (he's back!). You can ask your questions here

Canopy/Pergola roof pitch

  • 15-06-2021 3:00pm
    #1
    Registered Users Posts: 15,773 ✭✭✭✭ rob316


    I want to put a corrugated canopy/pergola on the back of the house, but I'm extremely tight with height as I need to get it under the existing boiler flue. I know the recommended pitch is 5 degrees for runoff but that will be too low on the end for me. Could you get away with going less? Would 1 or 2 degrees be totally insufficient?

    Thanks


Comments

  • Moderators, Society & Culture Moderators Posts: 31,294 Mod ✭✭✭✭ Gumbo


    rob316 wrote: »
    I want to put a corrugated canopy/pergola on the back of the house, but I'm extremely tight with height as I need to get it under the existing boiler flue. I know the recommended pitch is 5 degrees for runoff but that will be too low on the end for me. Could you get away with going less? Would 1 or 2 degrees be totally insufficient?

    Thanks

    Be mindful of your planning exemptions and also the distance from this plastic material to the boiler flue outlet as per Part J of the Building Regulations.


  • Registered Users Posts: 525 ✭✭✭ Fine Cheers


    Would falling the roof towards the house be possible of feasible ? Ok you wouldn't do it in an ideal world but a proper gutter with flashing chased into house wall should be fine. Or can you extend the flue ie run it up the wall ? Be mindful of the regs on this but it can be done. Photos would help.


  • Registered Users Posts: 30,331 ✭✭✭✭ Penn


    The main thing you also you need to take into consideration, which most don't, is bedroom windows over the pergola. If you have fire escape windows over the structure, it's not going to be in compliance with Part B requirements as it won't be a strong enough structure to facilitate access or egress in the event of a fire.


  • Moderators, Society & Culture Moderators Posts: 31,294 Mod ✭✭✭✭ Gumbo


    Penn wrote: »
    The main thing you also you need to take into consideration, which most don't, is bedroom windows over the pergola. If you have fire escape windows over the structure, it's not going to be in compliance with Part B requirements as it won't be a strong enough structure to facilitate access or egress in the event of a fire.

    One that is missed very very often.
    I’ve been called to jobs at the very end where people have put roof lights under the escape/rescue windows.

    Glazing had to be repaired to carry the loads or a steel frame built over them!


  • Registered Users Posts: 30,515 ✭✭✭✭ Lumen


    Penn wrote: »
    The main thing you also you need to take into consideration, which most don't, is bedroom windows over the pergola. If you have fire escape windows over the structure, it's not going to be in compliance with Part B requirements as it won't be a strong enough structure to facilitate access or egress in the event of a fire.

    Interesting! Would I be correct in highlighting this section:
    Windows for Escape or Rescue

    1.5.6
    ...
    (d) The area beneath the window externally should be such as to make escape or rescue practicable. For example,

    (i) where there is a clear drop from a window in an upper storey or attic conversion, the ground beneath the window should be suitable for supporting a ladder safely and be accessible for rescue by the fire services or others.

    (ii) Where there is a roof, balcony or canopy below a window, it should be structurally adequate to support those using the window for escape or rescue.

    I guess you'd need to be sure that it can be jumped down to from the window by an overweight adult to without collapsing or shattering, which isn't trivial to achieve.

    Source: https://assets.gov.ie/100071/0f55fb77-96a3-4dd5-8b93-7648880296e9.pdf


  • Advertisement
  • Registered Users Posts: 30,331 ✭✭✭✭ Penn


    Technically for a dwelling house it's a different document, the new Part B Volume 2, but the wording is generally the same

    https://www.gov.ie/en/publication/303fa-current-edition-technical-guidance-document-b-fire-safety-volume-2-dwelling-houses-supplementary-documents-supplementary-guidance-to-technical-guidance-document-b-fire-safety-volume-2-dwelling-houses-2017/
    1.3.7 Windows for escape or rescue
    (e) The area beneath the window
    externally should be such as to
    make escape or rescue practicable.
    For example;
    (i) where there is a clear drop from a
    window in an upper storey or attic
    conversion, the ground beneath the
    window should be suitable for
    supporting a ladder safely and be
    accessible for rescue by the fire
    services or others.
    (ii) Where there is a roof,
    conservatory, balcony or canopy
    below a window for escape or
    rescue, it should be structurally
    adequate to support those using
    the window.

    A pergola with opaque corrugated sheeting on timber is likely not going to be strong enough to adequately support the weight of those using the window (with particular regard to someone from the fire services with oxygen tank on their back etc) to walk across it safely to access the window. The amount of timbers/steel required under to provide fully safe footing (bearing in mind someone may not be able to see where the timbers are located under) defeats the purpose of opaque sheeting for light.

    But yes, if you can get someone to design and sign-off the canopy as being compliant with building regulations (Part B - Fire, Part J - Flue etc), then there's no issue.


Advertisement