DIY Home Improvement Forum banner
1 - 5 of 5 Posts

·
Registered
Joined
·
1 Posts
Discussion Starter · #1 ·
Looking for advice on materials for renovating a 7x30 uncovered deck over living space. Current deck has rail posts attached on top of the exterior walls below, forming penetrations in a hot mop waterproofing layer, sleepers fastened into joists through hot mop (more penetrations), and Cedar decking. We have leaks during big rain events

Plan is to strip deck down to joists, remove rails and posts, set new posts outside of joists using structural ties, install new plywood underlayment with good slope for drainage, apply some kind of membrane waterproofing without penetrations, lay sleepers on top of membrane glued, and use decking material suited for Seattle-area moisture.

I have run it by a few contractors and I have good agreement on the design, but mixed signals on waterproofing and decking material. One contractor recommends another hot mop roof. I had thought maybe EPDM. Was also thinking Ipe but was told its a poor choice for a sleeper system with less than 18" clearance for ventilation due to excessive buckling stress with moisture below. Thinking maybe cedar again or PVC/composite. It 1914 cottage-style architecture so a low-maintenance product with traditional look is what we're after.

I would love to hear from others having success with a similar deck configuration willing to share choices of materials and methods.
 

·
flipping slumlord
Joined
·
5,116 Posts
Looking for advice on materials for renovating a 7x30 uncovered deck over living space. I would love to hear from others having success
Beyond cosmetics... the joint at the house is the main issue.

You need to recreate that 'deck' into a 'porch'.
And to do it properly (vs what the previous owner attempted).
Properly probably means starting over altogether.

Like this:
 

Attachments

·
Low Slope Roofing
Joined
·
1,451 Posts
A hot mop would be the most durable solution, I would make sure it's a 3 plys of Type 4 felt and a smooth cap sheet. We have done a ton of them with EPDM also, on top of the new plywood a HD ISO cover board would be recommended then a fully adhered 60 mil EPDM. Most of the one we do the deck is "floating" on the roof material no need to glue anything to the roofing. Like the post above details in flashing the wall are of the highest importance.
 

·
Registered
Joined
·
290 Posts
Around here, these are often done with modified bitumen (torch-on) 2 or 3-ply membrane. I have done quite a few in TPO as well. Either cut the sleepers/joists to follow the slope so the decking boards are flat, or use proprietary pedestals to support the sleepers.
 
1 - 5 of 5 Posts
Top