Decking Joists

[D4wk1ns]

Hello!

My husband and I are planning a deck over part of our sloping garden. Maximum dimensions will be 590 x 280. The 590 side will be against the house, held on a ledger plate, with joist slung out 280 from there. There will be two rows of posts concreted-in with accompanying beams over which the joists will be slung.

My problem is - if I can only get joists 240 long, can I join/splice them together safely??

Ta!!!

 

[r896neo]

you need to search harder. I assume you have only tried your local diy store?

6x2 or 4x2 joists should come in 3.6m 4.2m and 4.8m from any builders or timber merchant.

 

[D4wk1ns]

You're right! Had a look around some of the non-standards and have got hold of what I need.

Looking at the load capacities on these joists I think I will probably only need one set of posts - 2x6 joist with a C16 rating at 40cm centres can span 3m, according to the tables I have looked at. So I might just put the ledger against the house and sling the joists out across a beam (notched into posts at 180cm centres) 2.4m from the house with a 40cm cantilever.

If I lay the deckboards at 45 degrees to the joists will I still need a cross-brace under the deck to prevent twisting of the structure? I would expect that properly secured deckboards would do the job.

Thanks for the advice!!

 

[Sombrero]

Wow !! this is the most knowledgeable question i think i've ever seen !!!

 

[WabbitPoo]

3m long joists will still bounce if you dont support the middles somewhere.

Noggins help prevent skewing.

 

[D4wk1ns]

Splendid! Will stick to two rows of posts and use noggins. Thanks for the advice!