Hoping you can help with a deck design.
I'm working from The Australian Decks and Pergolas Construction Manual sold in bunnings, but for the life of me can't make sense of the span tables. Or at least the design I'm coming up with doesn't seem right.
The deck is planned to be 3300 x 4100, Bearers running along the length, joists mounted ontop. The deck is only 500mm of the ground, and doesn't require a DA.
Bearers - 2/90x45 MGP10
Joists - 90 x 45 MGP10
Posts - DINGO 100 x 100 x 900m 6mm Reinforced Concrete Stump (as per the bunnings DIY video series.
The span tables seem to suggest a joist every approx. 1000mm, but every picture I see of a deck seems to have joists at 450mm.
Have attached the drawings fyi (and can provide the span tables in the back if it makes any difference! Any assistance from anyone would be greatly appreciated!!!
Note: the width of the deck has extended some I’ve drawn this. It’s now going to be 3300 wide.
Welcome to Workshop @marc_s. It's fantastic to have you join the community. I trust you will receive lots of assistance and inspiration from our ever-helpful and clever members for this project and many others in future.
I have tagged Chris (@BIM_Engineer) for you to ensure he sees your question.
Thanks again for joining us and please let me know if you ever need a hand getting the most from the site.
@marc_sWelcome to the forum
Unfortunately I am not familiar with that Publication
I would recommend though
For a 4.1m Length x 3.2m Width deck
Width 3 Stumps (2 equal width 1.60m centres)
Length 5 Stump (4 Equal length 1.025 centres)
2/120x35 f5 Structural pine 3.30m long
at 1.025m centres Nailed or bolted together
120x35 f5 Structural pine 4.10m long
at .450 centres for pine Decking or 600 Centres for hardwood decking
The decking generally limits the joist spacings centres either to 300,450,600mm
The current code is AS1684.2 Table 49 & 50 Bearers & Joists Respectively
Domestic Timber Deck Design for guide to decking Types,Sizes & Spans
Please leave a PM if you require further info on AS1684 or if you would like a free Sketchup Model
Hi @BIM_Engineer - thanks so much for this.
Looking at placing an order for timber and the only suppliers I can find in sydney only do either 90x45 or 140x45. I assume that would change the design in terms of spans and number of posts?
The 2/140x45 bearers will be running length ways, I've also decided to use joist hangers and install joists between the bearers rather than on top, due to lack of clearance (only around 500 mm from floor level to ground, so appreciate your thoughts on that as well.
Again, thanks for your help.
As you have correctly pointed out there are many variations, for materials , sizes, labour, Design, Engineering,Construction,etc,etc
but only one right solution that suits you.
i am looking at tackling a deck in my courtyard. My biggest issue is knowing the specs. Am I reading this right that you offer to draw up some plans for the space, including where to put posts etc
if so I can send through my dimensions.
Thanks in advance mate
Welcome to Workshop @davehendo. It's great to have you join us. We are looking forward to seeing how your deck project progresses.
I will tag @BIM_Engineer for you so he is alerted to your question.
Feel free to post whenever you need a hand or have a new project to share. And please let me know if you ever need help getting the most from the site.
Nice, How about some photos and more info?.. the more info you put up the better the answer.. general info to start off here
-You can find Specs & Details in the relevant Australian Standards and googling images, respectively
-Check with your local Authority as some low decks may not require Planning & Building permits
-try doing a rough sketch design either by hand or using Sketchup 3D , content is also available on Sketchup Warehouse
-States also have differing regulations regarding Engineering Certification & Calculation requirements
I am a big fan of DIY & Design,Engineering & Construction (DEC) automation... unfortunately there are regulations in play
BTW, whats gets put up also helps others
Hello and Merry Christmas to all,
As you can see I am a newbie but I will be asking many questions as I am about to endeavor in building a deck over existing concrete slab and around the back of the house over earth and concrete slabs ( when I can work out how to upload photos to this thread rather than start a new thread I will)
I have fare idea on what I have to do but any advice would be greatly appreciated!
I need to build the deck to eliminate the 140mm step down as my mother is having a difficult time doing so and budget is very tight as I am on a carers pension! I don't mind getting down and dirty
the area I have to sort is 7270 x 2660 , the existing slab slopes away from the house at approx 3deg .
I intend to run decking length ways using 90mm x 22mm pine board
joists will be 90mm x45mm using concrete bolt screws and window packers to level off! set at 450mm spacing but both ends will be around 405mm gap.
over the section of garden bed in corner I will use 90 x 45 bearers bolted to brick to support joists using joist hangers and 2 stirrups set in concrete and weed mat.
I will be repainting slab a dark grey or black so as not to see it through the gaps in the decking which will be, as advised 4mm - 5mm.
I would appreciate any advice on this project