Roof Deck Drainage Design

One of our readers rune eriksen sent us photos of his design for a home built deck drainage system and we were impressed enough to check it out.

Roof deck drainage design.

Proper waterproofing for a roof deck involves installing an epdm membrane and flashing around deck. The most basic requirement for proper plaza deck design is proper slope to drain provided by the structural slab. Unfortunately adding tapered insulation to re pitch a roof deck costs about as much as the rest of a re roof job. A rooftop garden with wooden deck and central glass floor adds a lush twist to your roof top deck.

Building offsets are common and create intersecting planes that contribute to drainage issues for low slope applications. Our exclusive dual functional structural deck flange and combination roof drains streamline specifications saving installation time and labor. Leaks around the flat roof drain seerp into the fascia aug 29 2012 terry weir mbe said. Drainage solutions watts roof drains provide flexible solutions for specifiers and installers in any commercial roof application.

For larger roofs siphonic drainage systems should be installed. You can also add small garden trees to aid to your green design. Flat roofs are prone to leaking even without decks because of design errors improper materials and improper installation. For smaller surfaces gravity drainage systems are the ideal solution.

One gully can drain at least 150 m2. Planters with foliage plants along the modified parapet improve the look of the deck. Design professionals frequently specify the minimum code permitted slope with little if any consideration of the resultant valley slope created by the intersecting planes figure 1 ponding water is commonly observed at valley intersections for low slope roof and deck. The trough and downspout design drains water away from your deck allowing you to create a dry patio or storage area on the ground level below.

Aco offers functional solutions which are specially designed for flat roof areas and which ensure the water is drained effectively. Many times when roof decks are installed they further damage roofs causing more severe leaking and drainage problems. If the deck is a steel deck appropriate roof substrate sheathing i e gypsum based boards plywood may be secured to the metal deck and the fully reinforced rubberized asphalt membrane applied to the surface. It might be easier to re frame a sloped surface to drain to a suitable roof edge.

Rooftop metal deck idea. Trex rainescape under deck drainage system.