You flat roof doesn’t have to be boring – many people create extra outside space on theirs by adding a deck and you can too. It’s not as difficult as it sounds but there are certain things to remember when undertaking a project like this.
Here’s what NOT to do:
- Tar and gravel roof with sleepers perpendicular to the slope
- If debris settles into the cracks of the gravel roof it will become a muddy sponge
- The sleepers become dams with any heavy rain
- Standing water eventually seeps through and rots the frame. Your deck, and roof, won’t stand a chance.
When building a deck on your flat roof it’s important to run the sleepers parallel to the slope of a new rubber membrane. This will allow any water to run off easily without ponding. Use extra strips of the rubber to pad the sleepers when you put them in. Rip the tapered sleepers before laying them down on the rubber strips. Remember not to use any fasteners that will penetrate the membrane.
Start with your straightest boards as the floating sleepers can move around but once a few boards are screwed down they will stabilize. Double check the thickness of the deck boards stacked on the sleepers before driving any screws down; use shorter screws towards the house where the sleepers are thinner. Final tip is to space your deck boards slightly to allow for drainage.
And there you have it! Now all that’s left to do is enjoy your new deck and admire the view from your roof.