cracked sealant round shower

jezmyers

the sealant i have around my shower keeps cracking. I have replaced it, left it to dry for 5 days and then a couple of months later it cracks again. Is it simply because i'm using cheap sealant or could it be something else?

thanks

ariba10

What you need is a sealant that does not dry hard.

There are sealants that are made specifically for shower trays and the like.

There was never a problem when you had the solid porcelain trays but the plastic ones tend to flex when you put weight on them.

jezmyers

i thought that's what i'd been using as it says for bathrooms/waterproof etc...

i shall hunt down the non dry hard stuff, thanks!

Jonesya

We had the same problem with our shower tray, the movement was too great for the silicone sealant so it tended to crack. After several attempts at resealing we tried a seal strip arrangement - 2 piece overlapping plastic seal the the overlap taking up any movement rather than the silicone. Fitted it about 9 months ago and touch wood it is still working ok.

http://www.screwfix.com/prods/61900/Bathrooms/Bathroom-Sealants/Teleseal-Shower-Seal-200ml

withabix

jezmyers wrote: »

i thought that's what i'd been using as it says for bathrooms/waterproof etc...

That sounds like you are using tile grout! What you NEED comes in a 300ml cylinder with a nozzle and fits in a skeleton gun.

Silicone sealants do not go hard - they will certainly NEVER crack as silicone is a permanently flexible product.

They might debond from the tile or the shower tray however, but that's usually due to the wrong product being used or soap contamination on the surfaces - you need to pre-clean them with acetone, meths or white spirit unless the bath and tiles are brand new - even then it's probably a good idea in 'critical' areas, to remove any oily film which may be present.

If you have a problem with movement, you need a sealant that is described as having a HIGH MODULUS (of elasticity).

jezmyers

withabix wrote: »

That sounds like you are using tile grout! What you NEED comes in a 300ml cylinder with a nozzle and fits in a skeleton gun.

Silicone sealants do not go hard - they will certainly NEVER crack as silicone is a permanently flexible product.

They might debond from the tile or the shower tray however, but that's usually due to the wrong product being used or soap contamination on the surfaces - you need to pre-clean them with acetone, meths or white spirit unless the bath and tiles are brand new - even then it's probably a good idea in 'critical' areas, to remove any oily film which may be present.

If you have a problem with movement, you need a sealant that is described as having a HIGH MODULUS (of elasticity).

haha no it's definitely sealant. it comes in a tube and you use the skeleton gun. Seriously it's cracking.

I'll try a different manufacturer of sealant. Like I said, it's really odd. Due to cracking in the middle (the part attached to the tray remains as does the part attached to the tiles), i suspect it's due to tray movement.

withabix

Ahhh you mean TEARING, not CRACKING!

Sounds like your tray moves too much.

Resistance of a sealant to tearing will be proportional to the width of the bead of sealant.

If you've got a very narrow joint, the sealant will not be able to accommodate enough movement.


There is a solution to this one:

Put something roughly the same weight as a person into the shower tray.

Apply the sealant.

Leave the weight in the shower tray until the sealant has fully set. (You will have to have a soap-dodgers day!).

Your sealant will not split now (unless the shower tray is free to move somehow), as you will have applied it with the joint in its widest position.