Mold Removal

How to lose those black mastic marks around your shower or bath.

Do you have horrible black stains around your bath or shower seal? Mastic looks great when it is first applied then 6 months later black mould starts to appear .Here is the best answer to it from me.
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  1. What causes these stains please. My bath is only installed 1 month and has black stain like this in one place along bath edge, oozy black if wiped and waterproof. Not a sign of a leak?

  2. The best, but most expensive way of completing the job is to install a bathroom ventilation/extractor fan. Take up the mastic and lay a fresh lot down. It should keep the mould at bay much longer. Bobs your uncle and fanny's your aunt, jobs a good on.

  3. Hi cumbriahandyman , when you say all you have done is make the mould disappear , that was the idea , if any leaks did occour some time in the future then simply remove the cover strip and reapply a fresh coat of mastic. I know the mastic must have an angle on it and be higher than the bath edge but it will still go black and mouldy 6 months down the line, which is why I am going down the route of covering over the mastic with something that will remain white with no mould.
    Kind regards,

  4. Worst thing you could ever do. All you have done is make mould and possible leaks disappear.

    The mastic must have an angle on it and be higher than the bath edge.

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