On Thu, 19 Jul 2012 09:41:58 -0400, "Don Phillipson"
wrote:

"Brooklyn1" Gravesend1 wrote in message
.. .
On Wed, 18 Jul 2012 12:18:11 -0400, Dan Espen
wrote:

Spennomort writes:

Hi - I am looking to install some decking to replace old unsightly
concrete and part of my lawn. I have removed the concrete and turf for
the intended area but am finding that the ground beneath is a little
soft and not draining particularly well.
I never had any problems with the previous concrete so am a little
concerned about how to achieve a firm base for the decking.
My plan is to put down a layer of pea gravel as a base and also mount
the decking on paving slabs (400mm square). However, is there anything
else anyone can recommend to give my decking a solid foundation.
Thanks in anticipation

Where are you?

He's obviously in the UK.

If your ground freezes you need to dig holes below the frost line and
pour cement into sonotubes.

By using floating pier construction that's no longer true.

In most jurisdictions, building a deck requires a building permit: and
the local permits office can usually advise free about alternative
foundation methods (e.g. deck blocks or sonotubes. The former
are preferred here on sand and Leda clay, despite frost a yard
deep in winter.)

The OP is in the UK. There are few places in the UK that receive hard
frosts let alone heaving freezes. And were there zoning laws there
about how one must fabricate deck post anchoring he'd not be asking
here.... he's merely asking for DIYer recomendastions based on folk's
direct experience. In the US a permit for adding a deck is for
property tax purposes unless it involves swimming pools/hot tubs,
etc., typically no one from the building department comes out to
inspect deck fabrication unless it's physically connected to the house
(one of the main reasons floating piers were developed), only
occasionally do they manually measure square footage, but usually
additions/area is determined from periodic aerial photography. I
doubt many if any municipalites in the US have general deck code per
se, only in special circumstances such as set backs from property
lines, and as most DIYers don't apply for permits the zoning officer
will catch you later, usually a couple three years later and then the
town will reassess your property and make it a bit to the high side so
as to collect for the years you cheated. They'll rarely fine the
DIYer but they certainly will a contractor.