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Discuss Suggestions for radiator pipework route around joist in the Fittings & Pipes area at

  1. pbkb

    pbkb New Member

    Hi All,

    I am currently renovating my house (first home) and what started as a bit of paint has somehow, on the list of current jobs is central heating and radiators throughout. I've hung most of the radiators and chased down walls in three locations (for downstairs radiators), the radiators upstairs I am hoping to run pipes under the floorboards. On a side job I've removed the ceiling in the living room ("It's only a bit of paint, I'll be done in a week") which has given access to run pipework but also revealed a potential headache due to the location the end joist (very near the blockwork).
    The chase location is not within the 0.25 to 0.4 window of which I am allowed to drill through the joist (my hope was to drill in correct location and run pipework in the void between the last joist and blockwork, but this seems unlikely now).
    To the left of this chase is the conservatory door and to the right is an external wall. The location of the chase/radiator is preferred because this pipework will also go through to feed a radiator in the conservatory on the opposite side of the wall.

    I am hoping that you lovely people could offer some suggestions as to what the professionals (who I should have got in in the first place) would do in this situation with regards to routing the pipework?

    As a second and similar question, this joist also seems to be in the way for a radiator upstairs as the bottom of the pipe will come out in front of the radiator (get in the way/trip/not look very good). Short of adding big spacers to the radiator brackets, do you have any suggestions on the routing? Again, this location is not within the zone that I can drill or notch (very centre of the joist).

    Many thanks in advance.

    P.s. Merry Christmas and a Happy New Year!

    Upstairs1.jpg Upstairs2.jpg IMG_20171220_200814.jpg IMG_20171220_200915.jpg IMG_20171220_200837.jpg IMG_20171220_200935.jpg IMG_20171220_200940.jpg
  2. Best

    Best Trusted Plumber

    Most joists are slightly oversized and will not be compromised with a tiny notch out of them.
    • Like Like x 1
  3. oz-plumber

    oz-plumber Plumber

    Are they Ciga radiators?
  4. pbkb

    pbkb New Member

    Thanks for the question, they are double panel oval tube type radiators bought in the UK from an online retailer (SOAK). Not manufactured or purchased from Ciga-radiators Europe.
  5. oz-plumber

    oz-plumber Plumber

    They look like Ciga radiators ( Ciga is one brand of these rads )
    Manufactured in China - not that that's a problem.
    Probably distributed globally under different names / brands.
  6. Chuck

    Chuck Active Member

    I'm not sure from your question exactly what it is you want to do. Is it 'notch/drill a joist' in a manner that is not explicitly allowed by building codes? If so, the correct approach is either (a) choose another route for the pipe, or (b) get a chartered structural engineer to advise and approve the work.

    My guess is that if you apply an appropriate amount of strengthening to the adjacent joist you'll be allowed to weaken the joist that is getting in your way. It's also possible that a proper calculation will show that the offending joist is oversized, particularly if the property is relatively old and 'sturdily' built and that a small notch will be allowable.
  7. pbkb

    pbkb New Member

    Thanks for your reply and for that information. Apologies if the question wasn't very clear. With regards to your first question: No, I intend to only notch/drill in areas that are allowed and stated in the regs.
    I am open to suggestions as to best practice from others experience. Such as, suggesting it is better to drill in the red zone (within permissible distances along joist) and use a 90degree elbow to run pipework behind the joist Or, use the 90 degree before the joist then pull up floorboard upstairs and notch the orange zone (within permissible distances along joist). An elbow connector will just fit up between the joist and the blockwork.
    Example notch and drill.jpg
    I just thought I can't be the only one who has been in the scenario and was interested to know what others have done.
    Many Thanks.
  8. NickH

    NickH Active Member

    If this was my job I'd lift a few boards and notch out the top of the joist to run my pipes wherever I need them. I'd be careful not to go any deeper than necessary and if I had any concerns about the strength of the joist I would glue and screw a length of timber or ply to the side of it.
    That's what I'd do.
    • Like Like x 1
    • Agree Agree x 1
  9. pbkb

    pbkb New Member

    Many thanks for the advice!
  10. Best

    Best Trusted Plumber

    I would have had the pipe chased directly centre of the floorboard above and a small notch out of top of joist. You will have a problem with wall, plaster and skirting board in room above where pipe is going though.
    • Like Like x 1
  11. pbkb

    pbkb New Member

    Many thanks for that suggestion and the warning of the plaster. The intention is to have new skirting and plaster throughout. Hopefully I can work around the pipes and insulation/conduit.
  12. MOSSEP

    MOSSEP Plumber

    If your not already aware, you can drill within 0.25 + 0.4 of the span of the joist, or notch between 0.07 + 0.25 the span of the joist. Your notches should not be more than 0.125 the depth of the joists. If your radiator is not in one of these areas then I would notch or drill in the correct places and then run to where you need to go.

    What is that plastic you have running to the single back box on the wall? If its for cabling I would use 20mm conduit, and if you are planning to plaster over what you have in the picture it is likely to crack later on if it doesn't have a good 15mm of plaster over it.
  13. gmartine

    gmartine GSR

    Just going to say the same...conduit seems excessively wide (for mains?) and certainly not recessed deep enough for a good fill and skim. You've hung the rads but have you decided on the new skirting yet, unless it's going to be identical (height) I'd remove and replace it and lift floor boards before settling on anything.
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