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Builders – Joiners Decking Frame material Size 16ft X 10ft?
Agriv8 - 23/4/13 at 07:23 AM

Builders – Joiners, Decking Frame material Size 16ft X 10ft?

The frame under my decking boards has started to rot and sag so I need to look at replacing it.

Decking is 16ft by 10ft , 16ft is the direction of the beams with 2 or 3 cross braces between each ‘Span’ decking board run 90 degrees to the beams.

Each beam is supported in the middle by a paving slabs / packing and will be a single beam 16ft long.

The decking is Rawl bolted to the house 1 end and the pond (breeze block construction – concrete filled centre) the other ( 4 M12 rawl bolts either end )

The corners will be a simple Lapp Joint ( as 1 end can be seem ) and the internal 3 beams will be on Beam hangers.

So I need to decide what size tanalised wood to go for the frame ? that’s the bit I am stuck on.

I have 2 very good builders merchants close that will deliver free for orders over £50

So over to the Collective

Thanks Agriv8

40inches - 23/4/13 at 09:32 AM

The same size as the old frame?

Agriv8 - 23/4/13 at 11:23 AM

quote:
Originally posted by 40inches
The same size as the old frame?

I could but Its made from second hand floor / roof joists so not tanilised and not sure of the size until I pull some bords up.

As I will be paying for New thought I had better go for a recomended size.

Have I managed to stump 'The LCB collective'

Ta Agriv8

mark chandler - 23/4/13 at 11:36 AM

I used 6" by 2" over a 4m span in my garage, it deflects around 1/2" in the middle now I have a bit of weight up there but it's not bouncy.

Only cost £100 for 8 lengths I think, direct from a sawmill

[Edited on 23/4/13 by mark chandler]

v8kid - 23/4/13 at 11:59 AM

more supports are the answer

100x50 nominal cls beams at 600 centers supported every 1.5m is solid and it only requires 1 extra support

cheers

tompat3463 - 23/4/13 at 05:16 PM

as a rule of thumb for floor joists in a house.

if you measure the span in feet, half the number then add 1 will will get the reccomended 2by number


example. SPAN= 12foot , half of 12 is 6 , 6 plus 1 is 7 you for this example ypu would need 7x2 joists.

The correct type of timber is a large factor to.


Floor joists in a house should c16 which is a graded type of timber for structural work.


I implement these rules for any decking I do so I think ive got your answer.

Cheers Alan

v8kid - 23/4/13 at 06:35 PM

quote:
Originally posted by tompat3463
as a rule of thumb for floor joists in a house.

if you measure the span in feet, half the number then add 1 will will get the reccomended 2by number


example. SPAN= 12foot , half of 12 is 6 , 6 plus 1 is 7 you for this example ypu would need 7x2 joists.

The correct type of timber is a large factor to.


Floor joists in a house should c16 which is a graded type of timber for structural work.


I implement these rules for any decking I do so I think ive got your answer.

Cheers Alan


Cool ROT ( rule of thumb)

I think this allows for notching for services - mainly plumbing and central heating so in this respect it is OTT. [I do like my TLA's] Also decking is not expected to be as rigid as house floors - a certain ammount of springieness adds to the ambience don't you think?.

However it (the ROT) illustrates the importance of intermediate supports - double the supports and half the joist size!

A further advantage to more intermediate supports is the load carrying capacity.

Eh! Do I hear you say?

What load?

Well I just spent a superb weekend at Loch Fyne in a rented holiday cottage with a wood fired hot tub. It was sublime! Fresh mussles picked from the seashore by moi accompanied by a few bottles of bubbly - And?

Yup the hot tub was on the decking. It was 8 feet dia and 3 deep.

I needed the bubbly to stop worrying it I was going to be washed out to sea by a hot tub tidal wave!!!

To cap it all for the first time I found a pearl inside a mussel! -what's more the decking did not collapse but was very "ambience"!

So the moral is - plan for the unexpected.

Cheers!

[Edited on 23-4-13 by v8kid]