Shower Silicone leaking after 8 weeks. It adheres to shower tiles well but not to Shower tray itself

FrankFalcon

Hi all

I fitted a new shower tray at home about 8 weeks ago.  Yesterday I noticed brown staining on the ceiling below.  On checking the tray it appears that the silicone isn't really well bonded to the plastic shower tray.  I fully expected to have to use some of that silicone eater gunk to get it off but it comes off the tray with not a huge amount of effort.  It seems to have adhered well to the wall tiles really well though.  Any ideas what the problem could be? Could it be the wrong silicone? Poor quality silicone? I have been doing a lot of work at home in the last year or so and I can't remember where I bought the silicone from.  I need to get it right this time.  Is there a premium brand of bathroom silicone that I can use that can be relied on? Is there a brand with a 2 part formula, as in superglue and the activator etc that will give an excellent bond? As I said, it's a bit of a faff to get it off the tiles but it comes off the plastic shower tray with a decent bit of friction of my finger.  If I get a screwdriver under the silicone where it meets the tray it peels up cleanly.  Don't get me wrong...The silicone is definitely stuck to the shower tray but not as good/firm/strong as I expected.  I will pay whatever I need to to ensure I get the best adhesion this time.  

Thanks all.

FreeBear

Clean both surfaces with alcohol - Something like isopropyl alcohol should do it.

There may have been some traces of a mould release agent still on the tray that prevents the sealant sticking properly.

flashg67

Is it possible the tray is moving/flexing a bit and breaking the seal? Not having a go at your diy skills, but it wouldn't take much movement. Did you silicone the sides of the tray before installing ,  then add a final sealing bead on top? . Might be worth removing the silicone and getting a fat person in with you (like filling a bath with water when sealing baths) to make sure any movement is taken up before sealing? I've used many brands of sanitary silicone and not found much, if any, difference in sealing qualities

shiraz99

As mentioned, prep is the key. Make sure both surfaces are cleaned thoroughly with with an IPA solution or meths. Apply a decent silicone, I'd recommend Dow 785+, and use a silicone profiling kit such as the Fugi kit to smooth the silicone rather than use your finger.

Ensure you give it at least 24hrs before using your shower again.

TELLIT01

It certainly sounds like the shower tray is flexing excessively.

John_the_Boy

I used this when I had a similar issue, not had a leak for 2 years now (fingers crossed) https://www.byretech.com/acatalog/ShowerSeal-Ultra-10-Half-Seal.html?gclid=CjwKCAjwq5-WBhB7EiwAl-HEkiVjxRc3BTaABzMsb1FbQF9kOjmf1Rmvk-s28PSn9-rrcqWI4iNtgBoC71YQAvD_BwE#aSSWK03_2f06_2f10

Rusty190

Me too @John_the_Boy.
Brilliant stuff and easy for a novice to deal with. 

Troytempest

flashg67 said:

Is it possible the tray is moving/flexing a bit and breaking the seal? Not having a go at your diy skills, but it wouldn't take much movement. Did you silicone the sides of the tray before installing ,  then add a final sealing bead on top? . Might be worth removing the silicone and getting a fat person in with you (like filling a bath with water when sealing baths) to make sure any movement is taken up before sealing? I've used many brands of sanitary silicone and not found much, if any, difference in sealing qualities

Be careful - you will have the pinko liberals on to you!

shiraz99

John_the_Boy said:

I used this when I had a similar issue, not had a leak for 2 years now (fingers crossed) https://www.byretech.com/acatalog/ShowerSeal-Ultra-10-Half-Seal.html?gclid=CjwKCAjwq5-WBhB7EiwAl-HEkiVjxRc3BTaABzMsb1FbQF9kOjmf1Rmvk-s28PSn9-rrcqWI4iNtgBoC71YQAvD_BwE#aSSWK03_2f06_2f10

So they sell a profile but you still have to use silicone to seal it fully. What's the point of the profile then, other than decorative.

John_the_Boy

More grip around the profile onto the shower tray, profile is also textured to improve the grip. I was sceptical but it has worked, for me at least. Another cheaper option is to use a profile tool to give you a 45 degree silicone bead rather than a concave shape - there is a thicker layer of silicone on the tray which in theory should be stronger.  Details here https://www.youtube.com/watch?v=_DI4hfHM_Hg

shiraz99

John_the_Boy said:

More grip around the profile onto the shower tray, profile is also textured to improve the grip. I was sceptical but it has worked, for me at least. Another cheaper option is to use a profile tool to give you a 45 degree silicone bead rather than a concave shape - there is a thicker layer of silicone on the tray which in theory should be stronger.  Details here https://www.youtube.com/watch?v=_DI4hfHM_Hg

Which is how you should be applying silicone in the first place.