Okay to lay joists flat instead for decking?

5 Nov 2010
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United Kingdom
I want to put decking down but I think it can't be done the normal way where a bit of pokery and jiggery is needed.

My lawn is higher than the existing patio next to the house. I am hoping to build a frame on top of this patio whilst extending it out about 2 metres into the lawn. I will dig out the required part of the lawn so that it will be level with the patio.


A big issue is that the step from house onto the patio is only about 10cm. The step is also a bit lower the lawn itself. Therefore, I'm wanting to simply lay the joists flat instead. Is there any reason why I shouldn't do this? In fact, I would have thought it would make the whole project sturdier! I believe I have to use some kind of joining brackets instead though.

I am however concerned about the drainage. I'm planning on having a fall out towards the lawn although the rain won't simply spill onto the lawn because the lawn will be slightly higher. Obviously the rain will also fall between the decking but because the joists are laid flat then the gap between the ground and the decking will only be about 50mm. With a weed membrane down as well could any problems arise or should it all be fine and dandy?

I'm sure one option would be to dig up the patio but that will create a lot more waste and effort!

Thanks very much and hope you can help.


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Your decking will bend. Joists sit up vertically rather than horizontally as joists are stiffer in that direction.

Your decking will bend. Joists sit up vertically rather than horizontally as joists are stiffer in that direction.


Thanks for your input. I understand what you're saying but in this case the joists will be lying flat on the ground so surely they won't bend? I totally agree if the joists were being used in a house such as supporting an upper floor.

Thanks again.
I take it you mean just lay the joist stright into the current patio slabs with my gap underneath?

Your joists will be sat in puddles all the time which will make them rot much quicker
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Well thanks for all your advice guys.

Looks like I'm better off extending the patio on the raised lawn!


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