[Greenbuilding] Decking a Boathouse Roof

[Koehn Chris]

Lynelle, 

You say the structure is strong enough to support a deck, and in the next sentence you say you’re concerned “about the weight..”
Suggest you’re first step is to get an engineer to evaluate the structure for it’s ability to carry the live and dead loads a deck represents. Roofs aren’t always.
Regarding the materials to use, I’ve had good luck with EPDM membrane with rubber roof guard laid over to protect it. On top of that, you could build a wooden deck on sleepers, or a tile deck on chairs, or something like what Ezytile offers.
Railings are often overlooked on flat roof decks and they can present challenges.

Regards,

Chris 
TimberGuides 
Van Isle, BC