"The Henchman" wrote
My wife wants my to build a wall to wall bookcase that is floor to
ceiling.
There will actually be 3 sections because we want the end sections to have
workstation or desks. These units will be fastened to the wall. My wife
and her
family suggested I make everything out of MDF which is cheep, easy to
treat
and easy to buy decorative faces and mouldings for.

However I'd like to seek opinions on how long 5/8" or 3/4" MDF will last
if
two adults and two kids use this type of configuration for 20 or 25 years
or
hopefully 40 years?.

It will last 10 year s as long as you never put a book on it or otherwise
utilize it. Otherwise, it will sag and look like crap in a short time,
weeks with a good load of books. Day with a decent span. .

MDF has poor flexural strength and is a rather poor material for shelves.
I can't think of a worse material other than cardboard. I'd use plywood and
put a wood face trim piece that will add good looks and structural rigidity.

Go here and plug in the numbers and see how much stronger plywood is
http://www.woodbin.com/calcs/sagulator.htm



This room will be used a lot we think.
Then do it right and do it once.