can I use 4"x2" for deck frame?

[Sarnie]

Hello all,

I'm currently preparing to build a 3m x 5m deck with a cat walk from the rear of the house to the deck which will be situated at the rear of the garden.Most of the forums advise using 6"x2" for the frame which provides me with a problem, where the deck falls there is exsisiting paving covering much of the area of the new deck and I only have 5" between floor and deck board level i'm using 19mm x 90mm Balau boards. My question is can I use 4"x2" for the frame or should I remove some of the paving and use 6"x2"? My level is set by the step at the back of the house and I can go no higher (unless I incorperate a step somewhere). I look forward to your replies.

 

[imamartian]

i'm not a pro, so don't know the answer to your question. But a couple of things to think about... if you had a party on the decking, you could have 12 x 16 stone blokes stood on it... 6 x 2 would hold up better in that case.

However, if you had your supports closer together, would that increase the load it could carry? taking that to extremes, if you had a piece of 4 x 2 supported an inch apart, how much load would you need to break the timber?

 

[sjroberts1]

most timber frame buildings dont even use 4" planks between floors and they are set at 400mm centers so i would say 4x2 would be fine as long as the spacing is kept to a short distance, just make sure that its pressure treated if its in contact with the ground

 

[JohnD]

4" planks

Are you talking about the joists or the floorboards?

 

[sjroberts1]

sorry, the joists i meant, reading this now has got me thinking of which way up the 4x2 timbers are going to be for his decking, if it was 4" then i would have written what i did. if the deck was 2" high then i probably wouldn't have

 

[Sarnie]

Thanks for the replies,

imamartian, very true about the amount of weight it could have on it at times, but as you say with using the the existing paving and plenty of concrete pads set in cement and 400mm centres for the joists and plenty of noggins i'm hoping that if the support spacings are right, 4"x 2" will suffice. As sjroberts said even my house floor joists are 4"x 2" so surely it will be ok for a deck. Again thanks for the advice .

Best regards,
Sarnie.

 

[Sarnie]

@ Sj I knew what you meant

 

[imamartian]

Thanks for the replies,

imamartian, very true about the amount of weight it could have on it at times, but as you say with using the the existing paving and plenty of concrete pads set in cement and 400mm centres for the joists and plenty of noggins i'm hoping that if the support spacings are right, 4"x 2" will suffice. As sjroberts said even my house floor joists are 4"x 2" so surely it will be ok for a deck. Again thanks for the advice .

Best regards,
Sarnie.

go for it, i think you'd be fine.... and don't forget to invite us for the party!!