Leaking and new Lead Flashing

Discussion in 'Builders' Talk' started by winterdiy, Nov 23, 2016.

  1. winterdiy

    winterdiy Member

    Hi guys,

    After a long wait, my sister had her kitchen build last year and the builder left the roof (where it joins the main house old gable end wall) as you can see in the attached picture. He basically just applied some mortar along the roof tile/wall joint.

    Needless to say, when it rained the water seeped straight down the joint, soaking the plasterboard ceiling and the plastered gable wall inside the kitchen. The water also seems to have travelled a good 3 or 4 feet across the middle of the ceiling and leaked down via a drilled hole (for a smoke alarm).

    To remedy the condition I applied Self adhesive flashing tape over the mortar (the tape was 12" wide so was able to cover the mortar and go up 6" against the wall). I also applied Thompson water seal to the old gable wall 5 brick courses above the flashing tape. It hasn't worked.

    So to do it up properly, am planning on removing the self adhesive tape, remove the mortar and fix real Lead Flashing (yes as I should have at the start). I'm an competent diy-er, but would welcome your advice and pointers please.

    Many thanks flashing.jpg
     
  2. 2shortplanks

    2shortplanks Active Member

  3. KIAB

    KIAB Super Member

    Wow!

    That will never be waterproof.
     
  4. Jitender

    Jitender Screwfix Select

    Ask at the roofing merchants, they may give you details for a lead worker in the area.
     
  5. b4xtr

    b4xtr Active Member

    if it's a cavity wall you might need cavity trays ?
     
  6. koolpc

    koolpc Super Member

    Doubt that
     
  7. winterdiy

    winterdiy Member

    Hi guys,

    The gable wall is NOT a cavity one, but an old (1900) solid brick wall and prior to the kitchen extension caused no trouble.

    Thanks 2shortplanks for the link.

    As I understand it, once I've removed the adhesive tape and mortar underneath it, I need to use a Code 4 lead and fix it using the step flashing method, embedding the lead 25mm into the brick joints, using clips and sealant.

    I don't think I need to lift up the double roman tiles, along the edge, to place anything underneath them. Or do I ?

    I want to do it properly and not have to revisit the same problem, so all your help is very much appreciated.

    Also had a quick look online and found this: http://www.ebay.co.uk/itm/CODE-4-LE...hash=item2a3fb1a903:m:mXqomCDEsJz4NxGKBXRTRswhttp://www.ebay.co.uk/itm/CODE-4-LE...hash=item2a3fb1a903:m:mXqomCDEsJz4NxGKBXRTRsw

    What you think?

    Thankyou again.
     
  8. Jitender

    Jitender Screwfix Select

  9. I would be calling the builder back in.

    Whats the guarantee on his workmanship? A leak on a new build isnt acceptable in my mind
     
    Deleted member 33931 likes this.
  10. KIAB

    KIAB Super Member

    Before fitting a lead flashing, you will needs plastic soakers under them tiles first, otherwise water will easily fine it's way under when running down the roof if you just use a lead flashing .

    [​IMG]
    Some great guides here explaining things.

    http://www.britishlead.co.uk/basic-fitting-guides
     
    Last edited: Nov 24, 2016
    Dr Bodgit likes this.
  11. Dr Bodgit

    Dr Bodgit Super Member

    The helpfulness of certain people on this forum never ceases to amaze me. Truly some great people here!
     
  12. KIAB

    KIAB Super Member

  13. winterdiy

    winterdiy Member

    Hi guys.

    I thought roof soakers and abutment flashing could only be used with plain tiles and slate.

    The kitchen roof is in double roman concrete tiles. Can I still use soakers/abutment flashing??

    Thanks
     
  14. KIAB

    KIAB Super Member

    Reading the Filon brochure, (linky below) they clearly say concrete tiles or slate.

    https://www.roofingsuperstore.co.uk/user/u/files/filon-v-flow-brochure.pdf
     
  15. Jitender

    Jitender Screwfix Select

     
  16. Jitender

    Jitender Screwfix Select

    Do it like in the video to provide min 150mm overlap over the tiles, dont need soakers. The felt may have been cut longer so just tuck under flashing on wall side.

    Did see a roof using large format tiles where they have just done it in smaller sections instead of longer strips, looked quite neat.

    Probably called single step overlap.
     
  17. Jitender

    Jitender Screwfix Select

    This is taken from the lead sheet association manual:

    Says to use code 4 lead, but 5 sometimes used if deeper profiles.


    upload_2016-11-24_18-59-9.png

    According to this you need lead 12" (300mm) wide. Lengths should be no more than 1.5m to allow for expansion.

    Apply patination oil after fitting and before it rains.
     
    Last edited: Nov 24, 2016
  18. winterdiy

    winterdiy Member

    Thank you KIAB and Jitender, much appreciated.

    I did just see this youtube vid showing an abutment soaker being used on roman tiles, so looks possible.

    TBH am amazed at how much water seems to penetrate through the joint in-spite of the adhesive tape, and would now rather overdo the job for peace of mind.
     
  19. Jitender

    Jitender Screwfix Select

    May be easier to do it in 'single step cover flashing'.
    as lead is going to be quite heavy at 12" wide. All depends on pitch of roof, but doesn't look greater than 30().

    Just cut this out from the manual:

    upload_2016-11-24_19-19-1.png

    upload_2016-11-24_19-20-2.png
     
  20. kiaora

    kiaora Guest

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