5mm expansion gap and upstand fitting

[8ball]

Hi all - I'm about to fit an 4m oak worktop and have been informed to leave a 5mm expansion gap along the back wall, is this correct?

 

So if the worktop expands and retracts that much how do you go about fitting the upstand as just fixing it to the wall and not the worktop will leave a slight gap between the upstand and the worktop allowing dirt to build up in that gap.

 

As always any help and advice is much appreciated ?

[joe90]

I always left a small gap at the rear of wood worktops for expansion and contraction and fixed the upstand to the wall and used 1mm spacers between the two, when dry remove the spacers and use a clear silicone to seal the gap, this will allow the two to move slightly and retain a water tight seal.

[Mr Punter]

Timber expands across the grain, so the issue is most tricky where you have a corner and the worktop has a wall at either end.  If it is a straight run you should not have an issue.

[8ball]

17 minutes ago, joe90 said:

I always left a small gap at the rear of wood worktops for expansion and contraction and fixed the upstand to the wall and used 1mm spacers between the two, when dry remove the spacers and use a clear silicone to seal the gap, this will allow the two to move slightly and retain a water tight seal.

 

Thanks joe90 this is what I was thinking just after I posted and now you have reassured me ?

 

7 minutes ago, Mr Punter said:

Timber expands across the grain, so the issue is most tricky where you have a corner and the worktop has a wall at either end.  If it is a straight run you should not have an issue.

 

Mr Punter I am lucky its a straight run so just the expansion gap at the back ?

 

Thanks guys for the help ... happy days

[ToughButterCup]

46 minutes ago, 8ball said:

Hi all - I'm about to fit an 4m oak worktop [...]

 

4 meters of oak: oak. Oak. King Hell. How thick?

[8ball]

22 minutes ago, recoveringacademic said:

 

4 meters of oak: oak. Oak. King Hell. How thick?

  ? ..38mm

[cherryfountain]

I assume you have the instructions for fitting oak worktops as you also need a couple of coats of oil on all raw edges and underneath before fitting and fit a vapour barrier above appliances like dishwasher and washing machines .The screws holding the worktop to the units also need to be able to move to stop splitting.

[PeterW]

6 minutes ago, cherryfountain said:

I assume you have the instructions for fitting oak worktops as you also need a couple of coats of oil on all raw edges and underneath before fitting and fit a vapour barrier above appliances like dishwasher and washing machines .The screws holding the worktop to the units also need to be able to move to stop splitting.

 

I usually drill a 6mm hole and put a 4mm stainless pan head in to hold it down so it can move sideways but not upwards

[joe90]

I used to use small metal brackets that had slots in them rather than holes, stainless pan head screws in the middle of the slot and not too tight. All oak worktops I have fitted come with instructions on fitting and treatment.