neb:Willuknight:So just a general comment, what's your building knowledge and skills like? This seems rather more complex than just concreting in some piles and laying a deck on them, which means you'd need at least some experience and specialised knowledge on how to do it. You really need to use the correct tool for the job for something like this, and for this sort of job I'd say the correct tool to apply is a builder. It looks like the sort of thing that a standard builder would do as a side-job over a weekend or two, which could save you a lot of headaches in terms of getting all the details right.
So I'm going to build a small extension to my deck to house a spa pool.
I've never built a deck before,
Where's the fun in that though?