Hi
I want to fit a couple of shelves to an alcove that is 57" wide.  The back and right hand walls are external but the left is a stud wall for the airing cupboard.

I would like to fit solid pine 3/4" shelving with a depth of 12".

What is the best way to support the shelves so that they won't sag under a medium load?

Thanks

I'm with BA on this one, 57in is way too wide for an unsupported shelf. If you want to know how much it wall sag then key the details into the Sagulator (follow the link) and you'll find out exactly how much it is going to sag (BTW the Sagulator reckons a 57in wide shelf, 12in wide in 3/4in Western white pine carrying a 50kg load will sag more than 3/8in (0.43in). If you think that's heavy, then I'd suggest that you weigh 1.5 metres of books - the weight may well surprise you

What the Sagulator doesn't tell you is that the sag may increase over time depending on trhe loading, atmospheric conditions, etc. (I ;live in the Pennines where the higfh relative humidity causes shelves to take on a gradual bow over time) For this reason I'd suggest the traditional approach of battening round three sides with something like 2 x 1 PAR pine and glueing/pinning your shelves to the battening would be the minimum extra support required, although BAs suggestion of at least one (I'd prefer two) uprights to support the weight woulkd be a lot better. If possible plywood or a good hardwood (such as oak) would make much more rigid shelves.

Scrit