Phil L wrote:
snip

sun, it also has downsides with relation to height - if your back
step from
the house is only eight inches or less, forget it as you need at
least this
just to have it level with the inside floor, it's better if your
patio is a
foot or more below dampcourse (house floor level)...ideally with any
outside
surface, there should be a clear six inches clearance (IE a step up
into the
house) from patio to house, this is minimum - the more the better,
but this
applies to all materials of patio construction, it's just that
decking is an
inch and half thick and sits atop six or seven inch beams....meaning
you may

Appologies for hijacking this thread. I've been thinking about putting
a deck which would lead off the patio doors at the back of my house. It
has a four step drop so I have the required height above ground level
to easily get the joists/deck level with the interior floor.
Unfortunately, I've probably been thinking about it too much and not
actually done anything about it.

My question is this, most of the sites I've seen say that the *deck*
should be at least 6 inches below the damp proof course (DPC). How then
do you achieve both i.e. level with the interior floor but not
adversely affect the DPC by damp bridging. I've so far come up with the
following ideas.
1. Build it freestanding i.e. not fixed to the house at all. Problems
with this I see are too much work and difficulty getting post in close
to the house/foundations
2. Put a membrane of some sort between the ledger and the wall to
minimize any damp bridging.
3. Stop worrying and just fix the ledger direct to wall as the flow of
air in/around the deck will keep things relatively dry.

My undersatnding of the six inch rule of thumb was that this was the
sort of height you could expect you average rain drop to bounce and any
less than that would cause the wall to get over wet. Obviously they
didn't take your average West of Scotland raindrop stoatin' of the
ground.

Given the way decks are thrown up I take it no-one else bothers about
these things?

Mark.