Silicone and shower enclosures

[Deejay]

Afternoon all

The instructions with an enclosure I'm fitting say to apply sealant to the outside only.

This can't be right, can it?

Does anyone know of a reason for sealing outside only, 'cos I'm beggared if I can think of one.

Cheers

Dave

 

[AndyP]

Duuno why Dave, but ours said the same thing 3 years on and no problems. Certainly with the silicon on the outside it stays cleaner. We have an alloy inclosure on top of a ceramic tray.

 

[9fingers]

External use only should help it develop less mould too.
Somewhere else recently the advice was not to scrimp on cheap silicone in bathroom type applications and use known brand and warranted mould resistance - some say up to 10 years.

hth

Bob

 

[Mike G]

Afternoon all

The instructions with an enclosure I'm fitting say to apply sealant to the outside only.

This can't be right, can it?

Does anyone know of a reason for sealing outside only, 'cos I'm beggared if I can think of one.

Cheers

Dave

This is almost a question for a philosophy class.

Do you try to keep the moisture out of something (the frame), or do you allow it in, and allow it an easy way out again? The former used to be the preferred ideology, but it didn't work because silicon isn't actually that good a product and gives up eventually. So the water will get in anyway, in the end. With the old policy failing, they have resorted to silicon on the outside to neaten up the appearance, and to prevent water going all the way through and doing some damage outside the shower, but allowing the water to get into the frame, safe in the knowledge that there is a designed path for it to get back out again.

It is much the same philosophy with feather-edge boarding. I've often seen people silicon up all the joints, put strips of DPC everywhere, fill all the knot holes, and so on, in the vain hope of trying to keep water from penetrating the boarding anywhere. Much better, in my view, to accept that it is going to get in (I mean, it's wood, for goodness sake), control where it goes, and allow it an easy way out again. That horizontal batten at the bottom of the wall wasn't such a good idea, was it?

 

[Rod]

Yes those were the instructions when I fitted my shower door several years ago.

No mould or any issues with it.

Rod

 

[Woodbloke]

Yes those were the instructions when I fitted my shower door several years ago.

No mould or any issues with it.

Rod

Same here with my shower. My workshop has been sealed with silicone for the last 10 years and has been completely waterproof, even through the little bit of dampness we had last winter - Rob

 

[TheTiddles]

Deleted

 

[Deejay]

Morning all

Thanks for the replies.

Mike and Aidan seem to have hit the nail on the head. Let it in and then let it drain away.

The top 'horizontal' surface, on which the frame sits, slopes down slightly towards the centre of the tray. Obvious if you think about it.

If you made a perfect seal on the inside, no water would get into the gap. However, a tiny pinhole will suck in water by capillary action, and it will just sit there.

If you seal the outside and leave a tiny pinhole, any water that gets through to the outside will not dribble onto the floor, 'cos of the slope on tray edge, and will evaporate.

Cheers

Dave

 

[Deejay]

Morning all

Just to close the thread, a reply from the vendor. I hadn't thought about water getting between the frame parts.

The reason Enclosures must be sealed on the outside is any water that can and does get between the glass and rails or inside the voids of the profiles need to drain back into the tray. If the enclosure was sealed on the inside, the water cannot drain and will build up and work its way out and onto the floor.

Cheers

Dave