decking questions

[b21playa]

Hi all

Planning to build a 6m x 3m deck at the back of the garden with no railings, which butts up against my shed with a ledger.

1. What size joists do I need?
2. Can I use preserved timber that is used for roofing timber (I have some left over)
3. Can I use 2 4x2 screwed together for the support posts?

Thanks in advance

 

[paul_v]

decking should be constructed with 4 x 2 joists

Preserved timber will be fine for the frame work. You should use the proper decking boards on top though as they have the grooves in them to give more grip under foot.

Probably not the best idea to screw 4x2 together to make 4x4, you will get mositure rising between the two pieces causing them to rot from the inside out meaning they will need replacement sooner than is you had used 4x4's.

 

[b21playa]

decking should be constructed with 4 x 2 joists

Preserved timber will be fine for the frame work. You should use the proper decking boards on top though as they have the grooves in them to give more grip under foot.

Probably not the best idea to screw 4x2 together to make 4x4, you will get mositure rising between the two pieces causing them to rot from the inside out meaning they will need replacement sooner than is you had used 4x4's.

Perfect

I'll get some 4x4s for the posts, use 5x2 for the joists (already have a few), and then use proper decking boards on top

It will be supported on posts on one side and fixed to the wall on the other. Do I need posts mid-span?

 

[paul_v]

by rights there is supposed to be a post every 1.5m so really you will need some or you will have a bouncy deck.

 

[b21playa]

by rights there is supposed to be a post every 1.5m so really you will need some or you will have a bouncy deck.

As the joists will be at 500mm centre's. can I put 1 on every other midway?

 

[paul_v]

yeah that will be fine, sounds like it will be a good deck when its done

 

[b21playa]

yeah that will be fine, sounds like it will be a good deck when its done

Thanks for the help.

Will bury the outer posts in the ground, and support the mid-way ones on some slabs I have left over

Just need to find sometime to start it off