Gooner's Deck Build

So some design details...

The final height of the deck is a mere 180mm at the door. That is the concrete slab to the height of the step which will be flush with the deck. At the end it is around 230mm to the ground.

- 6.3m wide x 5.4m long
- approx 975mm stirrup (effectively bearer) spacing
- 410mm joist spacing
- 500mm overhang onto the grass area
- Entire deck will be 140 x 19mm merbau screwed with 304 stainless 10G screws
- Handrails all around with two openings on either side.
- Frame is 90x45 F7 H3 treated pine

Due to the low nature of the deck, I decided to use Pryda stirrups. These are good because once anchored to the concrete, the joists are very easy to level using a few C-clamps.

I used two types. On the lower end I used the saddle type and as the height requirement increased I used the stirrup with the 65mm leg. Detailed cost of goods to follow, but generally these cost me around $6.20 each on average. Not bad.

However, I have a bit of a gripe with Pryda design. I was going to anchor these using Ankascrews. However, the saddle type has a pesky flange on it that means that you cannot physically fit the Ankascrew into the hole on the base. See first image below. Therefore masonary anchor sleeves are the only way to go.

Also, because of the flange it also means you cannot hold the saddle in place and drill the holes into the concrete. It also means you cannot use a socket spanner to tighten the nuts of the anchors.

The stirrup with the 65mm leg has two holes on the base and 2 holes on the saddle part. What would have been nice is if these holes lined up so that you could hold the stirrup in place while drilling the holes. But alas, this is not the case.

The second image below is looking from the bottom of the legged stirrup. As can be seen, the holes do not line up.

So there were 16 rows of joists and 6 stirrups for each joist totally 96 stirrups. They were anchored using mainly 50mm anchors with the last few using 75mm anchors. In retrospect the 75mm anchors were better and i should have used them from the start. What I noticed is that you have to screw these suckers in hard or else they have a tendancy to come loose.

So to start with I measured it all up and laid the rightmost row of stirrups (first image). Then measured along and installed the leftmost ones. Then measured the middle and built the support for the deck member that will run lengthwise through the middle of the deck.

General method was to measure up position of the joist and place stringline. Then install the first and last stirrup aligned with stringline. Then wrap stringline very tight between these installed stirrups and then line up and install the middle ones.

Once stirrups are in I simply put in the joists with packers and a double joist at the end for the overhanging section. Using a few C-clamps and a rubber mallet I then aligned the joist level with itself and the existing joists. I initially installed every second joist to get as much span as possible across the spirit level and then went back and installed the reamining joists.

Using the stirrups, C-Clamps and rubber mallet, you can very finely align the joists. Then tighten the clamps up hard, drill, and bolt the joist into the stirrup.

No rocket science there.

So after repeating that process several times, it was eventually all done. Took me about 6 days. (With half that time spent repeatedly looking for where I absent mindedly placed my texta, tape measure, drill bits, etc etc)

Where I am up to as of today is shown below.

The leftmost and rightmost joist sections were the hardest to do as part of them are against a wall and I had to blindly drill a 190mm hole making sure I managed to go through the hole in the stirrup. You can see what I mean in the last image. The joists are hung on the outside of the stirrups instead of the inside. I used 220mm long bolts to then clamp them onto the stirrup and then added some noggins to the adjacent joist to give it some extra stability. I had to angle grind the 220mm bolts down when inserting them into the areas near the wall and then had to get my hand in the small space between joist and the wall to get the nut in. Bit of a pain, but in the end the frame is largely done.

I have left the end of the joist long for now as I will lay the decking and then determine where to cut the ends of the joists. No point cutting them now and then having to lay the deck accurately according to the joist lengths. Especially as I am using 140mm merbau.

For those interested, here is a run down of my costs so far.

Main items left to buy is the merbau and the stuff for the railings. Also other items such as decking oil. I estimate around $2300 for the merbau. Will look at buying it this week.

Will post more the next time I get a chance to work on it further.

good post, nice to see our gear being used

we look a bit pricey on the batten screws in your list, just to clarify, these are $0.14 and $0.18 in trade packs of 100 and even cheaper in bulk packs, the minipacks you bought aren't very cost effective unfortunately because of the packaging.

Originally Posted by scruffydoo

good post, nice to see our gear being used

we look a bit pricey on the batten screws in your list, just to clarify, these are $0.14 and $0.18 in trade packs of 100 and even cheaper in bulk packs, the minipacks you bought aren't very cost effective unfortunately because of the packaging.

hehe, yep you are right. I bought the little packs thinking I'd need a few but underestimated how many I would need.

Everything else compares well. $1.32 each at Bunnings for the M10 x 120mm gal bolt and nut compared to your $0.85 and $0.81 each for the masonary anchors at Bunnings compared to your $0.51.

Of course the delivery needs to be factored into it all though..... but still works out well depending on quantities.