Flat roof help needed !!

[wanderer84]

Hi guys, looking for some advice to help me with a garden deck project. This site has saved me before and I'm sure this will be easy for someone who knows their stuff.

I have put up a deck framework and just about to order the boards but now want to make use of the space beneath for storage (deck is about 5 foot up). So my great idea (I hope) is to board the deck with 18mm osb 3 t+g boards, waterproof it then overlay artificial grass. This will work out cheaper, be a more child friendly deck surface and give a useful space below.

I'm looking for the best and easiest to install waterproofing option; felt looks cheapest but not sure it would last, epdm membrane looks like an option that would work but maybe overkill? It's 4m x 2m and given the time and effort to get this far I really want to get this right and avoid a rotten mess in 12 months time !!

Any advise or tips would be great

Cheers, Pete

 

[foxhole]

Sheet of dpc plastic would be cheapest option.Ideal put a slight fall on the deck so you don't have to much standing water

 

[wanderer84]

That's a great shout. I've been offered half a roll of tyvek felt from a mate which I understand will do the same job. Will be sure to put a bit of a drop on it cheers.

 

[Johnny Allround]

Epdm, it will also give you the perfect substrate to glue your grass to. Cheap isn’t always the best.

 

[foxhole]

I would run the grass over the sides and pin it to the edges, weight of it will keep it in place.