# Kitchen Worktop Joints - sealing recommendations ?



## Yetty

I need to butt joint two lengths of kitchen worktops to make a longer run. It's regular Formica Axion. I want to seal the cut ends to protect the joint from moisture.

Axion installation notes simply suggest using_ "...silicon sealant or contact adhesive..."_, but there are so many silicons in the Screwfix catalogue, so I'm not sure which to choose.

Any product recommendations most welcome!


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## Drudgeon

Trend do (or at least they used to)a range of worktop jointing compound/fillers, very similar to those in B&Q or anywhere else you may get a worktop from, they are very good, and waterproof, I had never realised how much adhesion they had until someone decided they wanted a different worktop only 12months after I'd fitted one for them, and boy was it stuck well.

Otherwise, pretty much any silicone sealant will do, obviously try to colour match as much as possible, mask up along each edge (keep a couple of mm back) put plenty of silicone into the joint and cramp it up, you can either clean it off there and then using spirit, or you can wait until it's dry around 24hrs later and cut it off with a sharp blade, either way work well.

If you have a joint next to a sink, you can seal the edge of the worktop with PVA first, that should keep the moisture out.


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## Max Power

Drudgeon":3nntpods said:


> If you have a joint next to a sink, you can seal the edge of the worktop with PVA first, that should keep the moisture out.


Very bad practice to have a joint alongside a sink  
What's the length of your worktop Yetty? Axiom comes in 4.1m lengths


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## blackrodd

Any cuts i do i always seal with a couple of coats of yacht varnish, still there a couple of years later
Regards Rodders


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## paulm

Drudgeon":12o29d13 said:


> If you have a joint next to a sink, you can seal the edge of the worktop with PVA first, that should keep the moisture out.



I didn't think pva was waterproof, or even water resistant ? 

I seem to remember threads on another forum about making sure not to prime walls with pva before tiling as any moisture afterwards through the grouting or elsewhere could cause the pva to soften/dissolve and the tiles fall off !

Personally I would use enough silicone sealant to seal the joint surfaces, and as said, plan to not have joints close to the sink in any event.

Cheers, Paul


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## jasonB

Colorfil, its made for the job, they should have a match to Axiom colours.

For cut edges that are not being joined such as sink and hob cutouts wipe on a good coat of silicon, contact adhesive as a second choice.

http://www.colorfill.co.uk/


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## Limey Lurker

>If you have a joint next to a sink, you can seal the edge of the worktop with PVA first, that should keep the moisture out.<



PVA is not suitable as a sealant on worktops. One of the worktop makers states this on their data sheet which accompanies their worktops.


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## Berncarpenter

+1 for colour fill but dont hang about with it get the joint bolted up strait away as it goes off petty quick. I usually scrape the excess off with my thumb nail and then clean up with colour fill solvent. HTH Bern.


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## Drudgeon

Unfortunately some people cannot avoid having a joint somewhere close to a sink due to space constraints, and I've never had any issues with a good quality waterproof PVA adhesive as a sealant, I've found it works pretty well, having said that, if everything else is done correctly then the moisture need never get as far as the core of the worktop.


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## chippy1970

As Jason and Bern say colorfill is what you need, should be easy to get hold of. Wickes, howdens and various other places sell it.


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## markturner

Sorry to disagree, but as a kitchen fitter of 15 years and a veteran of hundreds of worktop fits, silicone (clear) is the correct thing to use. Coat each side completely and bolt up, any excess will squeeze out. If you have machined the joint correctly, the edges of the formica should close together completely, thus negating the need for coloured fillers to disguise any gap ( which WILL let in water eventually). 

Cheers, Mark


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## Yetty

What a fantastic response! Just the what I'd hoped for, so thank you, thank-you, thank-you, thank-you.... 

The worktop run is over 4.6 metres, hence two pieces. To give the joint support, I've planned its position to be over a cabinet side panel beneath. Fortunately the sink will be about 0.7 metres clear of the joint.

Mark, if going down the silicon route, is there a particular brand & type that works well for you?


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## markturner

No particular brand, but don't use cheap ones - always a false economy. just make sure your customer ( or you?) understand, even a perfectly executed joint will let in water over time if its left lying on it, so dry it up with a cloth and it should last a long time. I like to creep up on a fit, gradually tightening the bolts and tapping it level until its perfect. If you tighten it up before its all level and then try and tap it level, the formica will invariably break, as it less compressive than the chipboard underneath and thus will stick out very slightly further once you tighten, so level first and then tighten. I use a piece of hardwood and hammer, and go easy. Done correctly, the joint should be almost invisible. use a new cutter and make sure the pieces are all properly supported and your jig clamped really tightly.


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## Berncarpenter

markturner":45rfbrcy said:


> Sorry to disagree, but as a kitchen fitter of 15 years and a veteran of hundreds of worktop fits, silicone (clear) is the correct thing to use. Coat each side completely and bolt up, any excess will squeeze out. If you have machined the joint correctly, the edges of the formica should close together completely, thus negating the need for coloured fillers to disguise any gap ( which WILL let in water eventually).
> 
> Cheers, Mark



In my early years of worktop fitting i used silicon for joints but although it forms a watertight and very strong joint i found it showed up the joint more than colour fill did .Have you tried it Mark ? I suggest you have a trail go at both Yetty and find out what works best for you. HTH Bern.


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## markturner

Well, like I said, there should be zero gap showing if its done correctly. And of course, you can slather too much silicone on which may hamper a tight fit. Its one of things that only experience can give you. A bad joint will need disguising and that's where colourfill can come in handy. But surely better to machine it properly in the first place.......

Also, surely you have some latitude, with 2 full lengths as to where this joint goes? There must be another cupboard edge or panel, further away from the sink that you can use instead. Having it right next to the sink is asking for trouble really.......

Some companies we fitted for used to supply a tube of colourfill with worktops for when we fitted their kitchens - I tried it a few times, but found it dried too quickly and made it difficult to pull up the joint properly. Silicone has a longer working time.


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## Max Power

markturner":if2bswwx said:


> Also, surely you have some latitude, with 2 full lengths as to where this joint goes? There must be another cupboard edge or panel, further away from the sink that you can use instead. Having it right next to the sink is asking for trouble really.......



Spot on. You want the joint well away from the sink, 700mm is a bit close.
Do you have a picture or plan of the layout Yetty ?


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## Phil Pascoe

700mm - that's over two foot three. I'd have thought if you had problems with water that far from the sink, you had done something wrong? It might not be perfect, but I wouldn't have thought it would be a problem unless the job was spectacularly badly done? 
I've just looked at the house we've just bought and the join is 4" from the drainer (right across the front). I shall have to be careful when I replace those tops!


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## No skills

Are you intending to bathe small children in the sink?

Cant imagine throwing too much water that far other wise


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## markturner

My bad, I read it too quickly and thought it was 70mm.......... 700mm is fine


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## Yetty

Again, thanks for all your input, it's appreciated. 

Here's a drawing of the kitchen. Full support under the worktop is at points A to H. The worktop comes in nominal lengths 4100mm.

Currently, the plan was joint at Point F, requiring lengths 1424mm and 3196mm. But sink is about 0.7m away.

Alternatively, maybe the joint could be positioned at Point G, using lengths 698mm and 3922mm. It's increases sink distance, but uses a shortish piece just 698mm long, I wonder if that might be more prone to sag.

Is position G better than F ?


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## fluffflinger

Debating Color fill v's silicone in kitchen fitting circles is like a sharpening thread on a bad day. 

I'm in the business and there is no clear winner, silicone is easy to source and very effective at sealing the surface and if the the joint pulls up well then it'd great however in some colours of top it does show quite clearly as a dark line but generally only if the surfaces to be joined aren't flush. Colourfill is designed for the job but there are many who will swear over time it will become a weak point. If it were me? I'd use Cascamite, waterproof, good gap filling properties and long working time, plus it will get penetrate into the chipboard which the other two don't (very much).

One observation as somebody who designs kitchen for a living, flip your sink to get more clearance to the left of the hob. You need to have sufficient space to feed in and out when cooking. Kitchen ergonomics and all that.


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## Alanka

I feel very strongly about this subject, having suffered at least twice from 'blown' worktops with all the subsequent hassle and expense that that involves.

To seal the cut 'chipboard' edges you should use a *good-quality white non-drip gloss oil-based paint*. PAINT because it's quick and easy to apply. WHITE because you can see where you've painted and where it needs a second coat or extra blobbing. NON-DRIP because it's convenient and usually THICK for good sealing. OIL-BASED because you don't want to apply anything containing water. 

Do not use PVA solutions because they are water-based, and although when dry they don't dissolve in water they still let through some moisture. They are not truly waterproof. Do not use silicones (caulks) because they are too thick or pasty to easily penetrate the chipboard surfaces and so are very difficult to apply and may not seal completely. Do not use a varnish, because it's hard to see where you've painted and where there are missed patches. It's also usually very 'drippy'.

There, I've said my piece!


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## blackrodd

Welcome to the forum.
In case you hadn't noticed, This thread is 4 months old.
I agree with you regarding the water based "sealer" 
As you can see on my earlier remarks, I like to use a good yacht varnish to seal any cut ends, has always worked for me. 
Regards Rodders


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## Alanka

Thanks for your welcome! Indeed, I had noticed the age of the topic, but late comments are still useful to people looking for help and info well after the topic has petered out, as I was.

Cheers, Alan


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