Decking help

Hi Alx1711

Firstly we need to know what timber your using ie Hwd or treaded pine
For unseasoned Hwd F17 it will Max span 2100 on a single span and 2300 over continuous, thats over at least 1 mid point. note these are max spans normally I would set 100 x 75 at 1800 centers

Joists 100 x 50 also at 1800 mm spans so the 1500's would be fine

to do the same in treaded pine
Bearers 2/120x45 joined, off set the joins so you dont need to join over posts
Joists 90 x 45 will span 2000 continuous

Hope it helps

Chipp69

For what its worth, I would always over engineer from the span tables. These tables specify the minimum required as per the standard, not nessesariy the ideal size.

Whatever the span tables specify, I would increase the timber sizes or reduce the spans by roughly 30%. The extra cost is negligable but the end result is far superior.

Ive seen far too many bouncy decks due to sticking to the "span tables". With your specs, I would avoid 90 x 45 joists- work towards 140 x 45 joists and 200 x 45 bearers in T/Pine. It will cost you about $200 more but the end result is simply a rock solid deck rather than a bouncy, flimsy, twisty deck.

i've gone through the timber decking manual and changed the timber sizes (Bearers and joists) as per attached.


BTW i am going for seasoned timber, Deck is for a mate of mine so i have no idea what sort of timber he wants. All i am doing is redesigning his house from sketch drawings using CAD Architecture so he gets an idea of dimensions and so on etc...


Now i need some help reading this table.
This is how i've interpreted the table (so please correct me if i am wrong )

Say hypothetically i am looking at Unseasoned Timber;
(all numbers are market below table)

1. I want bearer spacing of max 2400mm
2. It is a continuous span
3. say my deck width is 7m so > [ 7/3 (segments) =2.3 ~ 2.5 ] Based on table 2.5m min requirement (this is where i get confused, is 2.5m max span for 200x75 F8 timber? am i doing this right???? )
4. over engineer it; there fore i go for 2.9
5. alternatively my Bearer timber is F11 200x75

I can do up a video if i need to clarify it further?

Yes you are reading it correctly, If you are going seasoned Hwd then it would be F27 and Treaded pine you treat as F7

Thanks guys, i am gradually getting the hang of it
I'll be doing another deck shortly (for my place) and i'll see how i'll go.

I am using this Timber Deck Guide posted on this forum
http://www.renovateforum.com/attachm...deck-guide.pdf

which only mentions seasoned and Unseasoned timbers from F5 to F17.
where can i get the info about the timber Names, types and Sizes that are tabulated??

for eg. Chippy69 mentioned:

Seasoned Hwd would be F27 and Treaded pine you treat as F7!

need more info ...

Whilst most treated pine is f7- a lot is also being sold as f5 which you should take into account...

When you say seasoned hwd... Not all is f27- this is dependent on species as well as seasoning technique (kiln or air dried). You are far better "issuming" f17 for most hwd species (obviously unless specifically declared as f27...