What board for inside cupboard for shelf


Help Support UKworkshop.co.uk:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.


Established Member
19 Apr 2022
Reaction score
As per the title, what board would I require to use inside cupboards as shelves?

I'll cut them myself and inside the cupboards it would be supported by some wood drilled into the wall so all I would do is cut to size and then sit them on top of the wood attached to the wall and screw in.

I'm looking at B&Q Search results | DIY at B&Q
I'd be happy with an 18mm plywood for shelves in wardrobes up to 600mm. You should also be OK with this in kitchen units. On open shelves of bookcases you would probably see sagging on this span and be better off going for a solid timber.

what are the dimensions of the shelf and what is going on it?
It'll be clothing but would need to be heavy duty.

Measurement wise it would be for a few cupboards so length would be long as possible and width maybe around 1.5ft or around that measurement.
For that span you would need to have a stiffening batten to both front and rear of each shelf. Otherwise you would need very thick ply/timber to prevent sagging. MDF would be fine for the shelves and for the bracing to. Best to biscuit joint the bracing strips ( or some other jointing method along with glue.
No idea what ‘as long as possible’ means but I’m assuming the supporting wood screwed to the wall will be both ends and along the full length of the rear. If that’s the case, 18mm ply or mfc will be fine at 450mm deep, supported along the front as suggested. Personally, I would rebate the front batten so that it provides support under the length of the shelf and covers the front, cut edge.
The human eye will pick up even the slightest sag in a shelf so have a look at the sagulator to get an estimate. If you just want supports at each end of the shelf it will have to be extremely stiff or mill a 40 mm batten with a rebate to support it along the front edge as TomGW suggests. Avoid MDF at all cost unless it has support on all four edges. One wheeze I have used ( and posted here a few times ) is to use a new flush door which are generally 40 mm thick. Cut it down with a table saw exposing the 'eggbox' interior and glue in a batten on the cut edge between the outer veneer skins to restore strength. Flush doors are torsion boxes and extremely rigid. They can be painted or varnished.
Ok guys thanks for your replies!! Do you guys have a board for me to start with? I see the MDF at the link I sent in my original reply but I don't know if that's a good starting point?
I haven’t used blockboard for ages but it’s certainly a viable option for shelves. MDF will probably be the least rigid option so should be at the bottom of the list.