+ Reply to Thread
Results 1 to 2 of 2

Thread: Topcoat Problem

  1. #1
    Junior Member
    Join Date
    Aug 2014

    Topcoat Problem

    Need help in what to do.
    I have to replace the Topcoat on my flat root.
    How much do you have to sand it back, till mat shows or just sand to give a good key.
    Do you have to clean sanded roof with Acetone.
    Is it best to use Metrodeck roofing topcoat or normal coloured topcoat as old roof would not have used Metrodeck Roofing Base resin.

  2. #2
    Super Moderator Alex's Avatar
    Join Date
    May 2011
    CFS, weekdays, 9-5
    Ok so do as much as possible. It would be fine to just key it up, providing that the existing topcoat is sound, but if you allow topcoat to build up very thick then it can get brittle. So if this is going to be the third of fourth time this has been coated then I would want to remove some of the build up.

    Acetone is very good for removing contaminates and dust. Is it essential? No, but it removes a lot of stuff that may prevent the new topcoat from bonding or even curing.

    Normal or metrodeck are both ok, although there are no extra benefits from using metrodeck over normal for this particular roof.

+ Reply to Thread

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts