Worktop to tiled splashback gap

[Bromley86]

Just got the tiles up on the wall in our new kitchen and I'm looking to finish it all off now.

The gap between the tiles and the worktop is between 3 and 4mm, as the worktop slopes slightly over it's length. More importantly, the gap between the wall and the front of the tiles is up to 12mm and the gap between the wall and the worktop was, in places, up to 8mm (thanks Moben :) ). The cut edge of the worktop wasn't PVAed/varnished etc.

So I need a good seal. Moben did squirt some sealant into the gap between the cut edge of the worktop and the wall, but I don't want to rely on that. Likewise, although the units are screwed to the wall, I wouldn't want to bet that they won't move over time.

So my plan was to white grout except for that bottom gap between the tiles and the worktop and then pump lots of white sealant into the gap and smooth off. When I read the instructions for Unibond Bathroom & Kitchen Sealant

it said that filling gaps of >6mm can lead to failure.

Any ideas as to what I should be doing/using? Also any tips on how to grout and leave a clean gap for later sealing would be appreciated.

Many thanks.

[Owain]

Easy answer is get Moben back to remove and refit the entire worktop, scribed to the wall and level. That's a reasonable standard of workmanship to expect[1]. If they won't do that within 14 days, find someone who can, and sue Moben for the cost.

There really is no point in paying someone else to do it *and* doing it oneself. One might as well stand on a bridge throwing tenners into the stream below, and pretend one has a yacht.

Owain

[1] for a reasonable person with no prior experience of Moben

[Stuart Noble]

Sounds like Moben didn't get the worktop level or make any attempt to "fit" the kitchen, but slapping it against the existing walls might be what they were contracted to do for all I know. IMO the best thing at this stage would be to rip the tiles off, plaster the walls to eliminate the gaps, and re-tile. Maybe you can still salvage the tiles if the adhesive hasn't fully hardened. Patching things up doesn't sound like a option

[sm_jamieson]

You're not saying there is a gap between the front of the tiles and the worktop are you ? Just not much overlap - 12mm-8mm = 4mm overlap of the tiles with the worktop ? That's not *too* bad. And up to 8mm gap of thin air at the back. That is a touch much for silicone etc, would use up quite a lot, since it could "fall" down the back when applied. I might mask off the worktop etc and use some expanding foam. This would also stick the units to the wall and make the whole thing more stable. You would trim this off and paint with something waterproof. The 3-4mm gap is fine. Fill with silicone or acrylic sealant colour matched to either the grout or the worktop.

You can use an acrylic sealant that will do bigger gaps if needed.

Wedge into the gap a strip of thin wood / hardboard or something.

Hope that helps, Simon.

[Andy Hall]

None of the above. The job sounds shoddy. Putting in grout and sealer may effect a seal for a while, but gaps like this will be highly visible.

Contact Moben in writing, using Special Delivery to obtain proof of delivery, giving them 14 days to come and replace the worktop, scribing it properly to the wall.

In the event of their not doing this, the courses of action are:

- Withhold payment until it is done. (You haven't paid all of their charges have you?)

- Contact your credit card supplier or other credit supplier. (You did use a payment vehicle covered by the Consumer Credit Act?)

- Be prepared to initiate a Small Claims action.

[Bromley86]

Ah - looks like I was too accepting. And that's after I must have earned their "Biggest Pain in the Arse" award getting them to install correctly and fix things :) . Seriously, the 3-4 day install took 6 weeks as it was and although I was horrified at the worktop gaps, I figured we could live with them.

Just to clarify, Simon is correct about the tiles having at least a

4mm overhang (and in places where the worktop is tight on the wall a 12mm overhang). So:

WALL---|----8mm gap----|---4mm tile overhang---|

That up-to-8mm gap has been filled by Moben with sealant level with the worktop. How good that seal will be in 5 years (or even now) . . . Still, it will presumably stop whatever I do push into the gap from falling down behind the units.

With those clarifications, hopefully the problem isn't as bad as Stuart, Owain and Andy thought. Likewise, hopefully I can avoid the expanding foam route suggested by Simon (with my skills I can see that going horribly wrong).

Simon said that I could use an acrylic sealant. Would that give as good a watertight seal a silicone and would the visible bit last as well? Is there a special one or do I just buy the most expensive one in my local DIY store?

Thanks for the tip about the hardboard. Do I remove it before the grout hardens?

Naturally it goes without saying that I find myself unable to recommend Moben!

[Andy Hall]

They rely on that.....

OK, that's not quite so bad. Are these thick tiles to achieve that? Otherwise how are you achieving this range?

I would look at making sure that the units are rigidly secured to the walls so that there isn't movement.

[sm_jamieson]

I would remove it when the grout has hardened fully, else you might pull some out. Make sure the hardboard somehow has some "give" when you push it down (e.g. newspaper under then pull it out), so you can break any hardboard/grout seal without forcing the grout outwards, if you see what I mean. A lot of words for a simple thing. Or, cling film over hardboard, wax hardboard with candle etc, to act as a release agent.

Ooh, there's been warnings on this group ! Good luck.

Simon.

[Ed Sirett]

Trouble is that Moben weren't able to do it right first time and second time that likely are able either.

So it comes down to pay Moben nothing. Defend their claim in the small claims court.

Decide on the bets way to fix the problem. Some pictures will be useful. You won't get a perfect job unless you really sort out all the problems but you might be able to get a good enough one.

[Ed Sirett]

It's not necessary to scribe the worktop to the wall if the gaps are less than 50% of the (tile+adhesive thickness).

[Ed Sirett]

0) Make sure that the worktop is firmly supported, it should not sink more than 1mm when an adult walks on it (don't walk on the bit near the draining sink/board/hob). 1) Grout the gap flush. 2) When fully set (2 days) use a suitable sealant such as silicone or CT1 or even at a push an Acrylic. 3) Consider you have now passed the unit from the Univ. of life called. Why I should never deal with Moben/Dolphin(Shark)/Sharp.

[Bromley86]

Yep - if only I'd looked for reviews on the internet first. Incidentally, their contract is for 100% payment on delivery (which should have been another hint, Qualitas or no Qualitas).

8-9mm tiles with the balance in adhesive.

I did see that they were attached to the wall (one per unit), although I doubt that the individual attachments were all that stable. They looked like an angle bracket fixed to an offcut that was screwed to the projecting side panel at the rear. On the plus side, it's an L- shape and the worktop has been screwed to tall units at each end of the L, so hopefully the whole thing has some stability. Either way, there's no real way for me to check now (short of jumping up and down on it).

[Bromley86]

Thanks Ed. It doesn't seem to move much (I can barely see it and then not everywhere). I'm tempted to go this way as if it all goes pear shaped digging grout out is probably easier than digging sealant out, especially if it hasn't cured properly inside the gap. Plus this way I can use silicone where the manufacturers seem willing to give far greater guarantees of it's lifetime.

On the University of Life thing, I'm a total convert to getting established locals in now. When we got the windows done they were the cheapeast, best product and great service.

[Bromley86]

Much appreciated - I wouldn't have thought of that, which would have led to a little stress :) .

[Owain]

Quite possibly, but they have to be given a reasonable opportunity to remedy the situation, unless they are really so awful it is impossible to have any confidence in their ability to do so. I think it would be fair to insist on a different team of fitters to do the repair.

Owain

[Stuart Noble]

So, if you can lose the wall/worktop gap with tile thickness + adhesive, I assume your only problem is a tapered gap between the worktop and the bottom edge of the tiles. You can't really make a good job of this with sealants because, whatever you use, it'll get grubby. Some kind of upstand might be better.

[Bromley86]

The height dimension of the tile-worktop gap is indeed tapered, but only by 1mm along 3m so I'm not expecting any problems. It's only 4mm high at the maximum so likewise I'm not expecting any problems.

My concern was the depth of sealant. I don't know anything about how sealants cure, so I'm concerned that 4mm high and 12mm deep and 3m long "wedge" of sealant might just never go solid, might shrink or might [insert horrible thing I haven't thought of].

There won't be a problem with the sealant falling down the worktop- wall gap as it was filled with sealant by Moben (a bit haphazardly, but certainly well enough to stop grout or sealant falling behind the cupboards).

Although Ed's got me thinking of filling the tile-worktop gap with flexible gout and then silicone sealing on top, I'd happily create that huge silicone wedge if I knew it would dry properly with no unpleasant surprises. Anyone have any experience of over-deep wedges of silicone?

[Andy Hall]

Yes, and I don't think you need to be concerned about it.

I recently needed to seal at the back of a surface mounted cloakroom basin. This is nominally square but of course isn't because it needs to be removed from its mould during manufacturing. Therefore, the sides have an 89 degree angle relative to the horizontal. This, plus a slightly rounded top at the back leaves a gap next to the tiles of a couple of mm at the top.

It could have been left, but I decided that it could become a dirt trap and therefore wanted a minimally visible seal. I did this in the following way:

- carefully cut and folded white A4 paper pushed well down into the gap at the back.

- a light misting of water with a plant sprayer.

- first run of Dow Corning clear silicone sealer filling most of the gap. Allow to cure for a couple of hours.

- another *very* light spray of water

- second run of silicone slightly over size

- tool the silicone using a plastic tool of the required shape and using a solution of washing up liquid as a release agent. A plentiful supply of kitchen paper is needed to wipe the tool, then dip it in the detergent solution.

For this application, I can recommend the Fugenboy, made by Elch and sold by Screwfix. There is a similar product by another German company called FugenAss. However, for some reason, they have not had a lot of success marketing them in the UK. You can buy them in France. I'm not sure that Elch got the marketing any better but either way, these work well.

The purpose of the light misting of water is provide moisture for curing of the silicone. If the surface becomes visibly wet, then it's too much.

[Bromley86]

Priceless :) .

Thanks for the detailed description.

[Stuart Noble]

No problem with the curing, and this isn't a large wedge by silicone standards