The term expansion gap, when used in conjunction with wood flooring refers to the space left around the edges of a room when a floor is fitted.  Normally a space of between 10 and 15mm, it’s not a huge amount of space, but it’s enough to help prevent problems with wood flooring when it expands and contracts.

Wood is a completely natural product and as such, when it heats up and cools down and when it takes in and lets out moisture, it expands and contracts.  This is completely natural and normal, but when expansion and contraction takes place in a restricted space it can cause problems.  This is why expansion gaps are absolutely essential when fitting a wood floor.


Why are expansion gaps necessary?


If you imagine anything that expands and contracts in a tight space, you can visualise why expansion gaps are necessary.  As we have already explained, when environmental conditions vary; when temperatures rise and fall and when moisture levels fluctuate, wood becomes ever so slightly bigger and then smaller, ie.  it expands and contracts.  When this happens on a wood floor, if there is no space to allow for that expansion and contraction, the wood planks quite literally squeeze up against each other until they either bend outwards or rise upwards at the edges when it expands and then develops gaps when it contracts again.

In wood floor terminology, you’ll often hear the terms cupping and bowing when referring to the rising upwards at the edges and bending in the middle respectively.  This isn’t good news either for the stability of the floor or for its look.


Are expansion gaps necessary for solid and engineered wood flooring?


The short answer to this question is “yes”.  Although engineered wood flooring is more resistant to expansion and contraction than solid wood, it is still important to leave an expansion gap when installing an engineered wood floor.


What’s the best way to allow for an expansion gap?


The best way to allow for an expansion gap is to use spacers around your room when you fit the floor.  As already stated, you need to leave between 10 and 15mm all around your room.  Ideally, you should place a range of suitably sized spacers against the wall you’re fitting against as well as against the two walls where the floor will run.  This way you’re sure to get the right size of gap.


Won’t an expansion gap look ugly?

In normal circumstances, once you’ve fitted your floor, you’ll be replacing the skirting board that you’ve removed around your room to enable fitting.  As soon as you do this, then the gap will be hidden.  If you don’t have a skirting board in your room and you’re fitting a wooden floor, now might be the time to think about introducing one.

Alternatively, you can buy curved mouldings that can be added around your room to hide the expansion gap.  That said, the great thing about skirting boards is that they protect the bottom of your walls from bumps and scrapes that happen when you’re vacuuming as well as marks from when you’re mopping, so it is probably a good idea to at least think about adding one if you don’t have one already.


How can you check if you have an expansion gap?


If you’re reading this article and looking at a floor that’s perhaps cupping or bowing or has excessive gaps, you might be wondering whether or not you have an expansion gap in your room.  The easy way to check is by lifting off your skirting board and taking a look.  It really couldn’t be any simpler.

If you have a wooden floor that’s facing problems or you’re looking to invest in a new wood floor, why not get in touch?  At Wood and Beyond we’re always happy to help our customers make the right decisions for their projects and are here to give you advice whenever you might need us.