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Hello
I am looking to build a deck at the front of our home which is a converted steel shed on concrete slab. The deck is quite large 12m x 5m overall and it sits under a pergola that has just been completed. (see attached drawings and images.)
I am concerned mainly about the deck's height from the ground which at the lowest point would only be about 160mm and at its highest point 885mm (this is fine; I will do steps at this section).
The lowest point, being 160mm from ground to top of deck leaves only 140mm for bearers and joists, with the bearer sitting on the ground (using a 140mm bearer) and the joists flush to the top of the bearer. I expect that I need the bearer to be a minimum of 75mm from the ground.
Is that correct?
What should I do to make this workable?
Is a 140x45mm H3 timber bearer suitable? or should I go to a steel purlin/box section?
Should I dig it all out to increase the space underneath? how much?
about the number of stumps
hello @EricL @MitchellMc @Dave-1 @AlanM52 @Nailbag
I learnt a valuable lesson on the weekend - do the excavation work before you build the pergola - the good news - the operator only bumped it once and we got the ground down a further 200mm to improve spacing under the bearers.
My question for y'all, (the experts that will prevent me from making a total mess-up)
Which is better:
1. 100x100 cypress pine stumps connected to a concrete foundation (600mm deep) using stirrups, OR
2. 100x100 cypress pine sunk into the concrete foundations by 500mm (using a bitumen paint for additional protection)
Your help is greatly appreciated
Hello @Minyarra
I prefer traditional methods, and your use of bitumen paint is right up there on my list of things to apply when using a timber post. I'm putting my vote on number two as it is straightforward and not difficult to level or trim when it needs to be adjusted. It would be interesting to see what the others will vote on to use for your deck.
Eric
They are the better option when you're using timber that can't be concreted in the ground, like H3-treated Pine, @Minyarra. Concreting a post into the ground is really the most secure solution.
Mitchell
Morning @Minyarra
I will go against the grain... 
I prefer option 1, Stirrups in concrete mean I will have way less chance of the post rotting and I like knowing that the post is connected to a solid base.
Dave
hello @Nailbag @Dave-1 @MitchellMc @EricL @AlanM52
next question;
what is the best way to fix bearers to posts? and then, what is the best way to fix the joist to the bearer
I am using 100x100 cypress posts buried in the concrete (sorry @Dave-1 ) with 140x45 bearers and 90x45 joists.
option 1 - Is it satisfactory to 'hang' the bearer off the post (this is much easier) or
option 2 - cut the bearer into the post
Then, what is the best way to fix the joist to the bearers?
a) pryda joist straps (one each side) fixed by nail or by screws
b) 150mm bugle batten screw from the top
c) both
d) something else?
Thanks again
Good Afternoon @Minyarra
lol No worries at all.
I have used and prefer option 2, but I only cut into the post by a max 1/3rd so it gives a base for the bearers to sit on taking some of the load without weaking the connection point too much.
Just went and checke dmy deck, I actually went half way through 
mmm I still prefer 30% of the posts width tho.
Pool deck stage 1 is my project, there is a part 2 and later on an update if you troll through my bookmarks
Dave
A rebated joint is the most secure method as the weight of the bearer sits directly on the post, whereas with the side attach method, the only connection is through the fixings @Minyarra.
For connecting the joists to the bearers, I'd go with a Pryda Joist Strap 162mm on each side, fixed with Pryda clouts.
Mitchell
