sealant behind the kitchen sink

Adam Funk wrote in news:resi9dxn92.ln2 @news.ducksburg.com:

Had you used cheap sealant - or do you never give it a wipe with bleach? Wiping with a scourer is bad as it leaves scratches that breed mould. It really should last for ages.

Would fitting an upstand help? I don't know if it would, it's just what I am thinking of doing to mine.

I have stuck a plastic corner-moulding strip to the wall behind the sink, so that it overlaps the sink. Any splashes run into the sink and not the wall.

My main issue at this interface is that there is always some movement between the two surfaces through expansion or vibration or loading and its this that eventually breaks the seal as the malleability of the sealant reduces with age Brian

I have to admit, I've always thought "kitchen & bathroom sealant" would all be the same, so I probably use Wickes own brand. Does it really make a difference?

Well, that's the reason to use somewhat flexible sealant rather than inflexible grout, isn't it?

It may be to late to do this, but over the years I have resolutely moved away frim sealing the tiles to the horizontal surfaces, precisely because of these issue,.

Instead I seal the *WALL* to the horizontal surface and then tile over that. Grout completes the joint.

Grout doesn't seem to attract mould as much and can be scrubbed clean more easily

Well no.

a hairline crack in the grout doesn't natter if it's *sealed behind the tiles/grout already*.

Your approach sounds good & I'll file it for future reference, but it won't work in my existing arrangement.

It's too late for the current kitchen, but I have a similar issue in the bathroom, where I recently pulled out the sealant around the bottom & sides of the window (the stuff at the top was all "clean").

Would you recommend applying sealant *into* the gap only, then (after that's dry, of course), adding grout?

What do you recommend for whitening old grout?

thanks

I had to look "fugi" up, but I know not to get sealant wet before it sets fully (I admit that I usually use a finger in a latex glove).

I'll take a look.

well that's not gonna be tiled is it?

Not sure that grout would actually stick that well.

In that case I'd actually use decorators caulk.

And paint over it

bleach.

If I'm caulking anyway, what's the point of using decorator's filler, rather than "kitchen & bathroom" stuff, in the bathroom?

Because silicone isn't paintable and goes mouldy, whereas decorators caulk is acrylic, and doesn't go mouldy, and is paintable

Why do they sell silicone as "kitchen & bathroom" then? Just a conspiracy to sell more caulk, or is the acrylic stuff more permeable to water?

Yup. Acrylic is not fully waterproof

Basically silicone is the water sealer, but has huge downsides visually.

But where you are e.g. sealing wood, well that's got a paint water barrier anyway, so you can paint the acrylic just the same.

Acrylic most certainly does go mouldy.

Interestingly enough the Wickes stuff I used 30 years ago hasn't?

I guess that fillers do not "Go Mouldy" - but more a case of the cleaning methods case it to grow mould.

A wipe with bleach usually fixes the problem. Also bleach the area before applying filler.