"Vass" wrote in message
...
"The Medway Handyman" wrote in message
.uk...
Vass wrote:
free standing decking (i.e. not fixed to wall of house)
20 foot x 12 foot, blinking heavy it will be
I'm using 9" x 1.5" joists and I can hardly pick each one up as they
are currently 15 foot long
SNIP
I've built bigger decks than that, and I use a combination of methods;

Use a post hole digger http://www.wickes.co.uk/invt/501584 to get a nice
round hole, go down about 16 - 18", drop half a brick in the bottom, drop
in post & fill with postcrete.

I built my deck a couple of months ago. about 3.6 x 5.4m (3.6m cos of timber
length of course, although it did also happen to fit). I did not dig holes
for the posts. Everything is fine and solid as the weight of the deck holds
everything down, BUT if I was doing it again I definitely would concrete in
at least the main corner posts. I found that not doing this caused
everything to move out of square every so often, with all the hammering and
general bashing about. The middle posts can just sit on a block or a couple
of bricks. In fact in a few places I just stacked up old bricks with a slate
top bit. By the way, I bought a big pack of coach bolts from screwfix and
they were great for screwing joists together and for holding warped joists
in position once the warp had been corrected.

Hope you get good weather!

Alistair