Subscribe or Renew Membership Subscribe Renew

Transparent roof over porch...

EricGunnerson's picture

I have a kitchen deck that needs replacement, and rather than putting in another deck (decks facing north aren't of much use in Seattle), my wife and I have decided to do a covered porch instead. The area to cover is 24' x 9', and it's at the gable end.

The problem is that my designer (aka "wife") has decided that a solid roof is a no-go because of the loss of light through the windows, so I'm exploring other options. I'm considering two options:

1) Doing a conventional roof and put in a few skylights. The advantage of this is that I know how to do it and I don't envision any problems getting plans approved.

2) Building a roof with polycarbonate panels (like those used for greenhouses). There's more design work there, possible more problems with permits, and a more complex assembly and flashing. And the resulting roof won't be as walkable.

Has anybody tried the second option, and if so, what were your experiences?

(post #104987, reply #1 of 6)

We did our enclosed deck about 20 years back with translucent corrugated fiberglass panels. Eight ounce clear, not the typical 5 ounce green carp you see at Menards.

Has held up well other than the fact that it got pretty dirty at all the laps.

If your view never changes you're following the wrong leader

Of all the preposterous assumptions of humanity over humanity, nothing exceeds most of the criticisms made on the habits of the poor by the well-housed, well-warmed, and well-fed.  --Herman Melville

(post #104987, reply #2 of 6)

We installed one last winter, the opaque 1/2" Lexan hollow ribbed panels.

Piece of cake.  Supplied screws were missing, we used rubber gasket metal roofing screws, NOT TOO TITE!

Cuts easy, light , keep water out they sell a tape for the cut edges, and C Channel for exposed edges, H channel for field joints.

IIRC framing was 24" OC and purlins ( strapping) was 24" as well, in our job someone else installed the 1x3 strapping, but they did it like blocking, inbetween blocks, not long straps, and worse was it was toenailed into the rafters w/ finish nails 4 per block...sleeeting out side, icy rafters, both of us wound up falling thru a bad /loosened "purlin" that NOT do that, if ya want it all flush, notch the tops of the rafters and use continueous strapping..

Thats how I remember that working that day.

Spheramid Enterprises Architectural Woodworks

"If you want something you've never had, do something you've never done"  

(post #104987, reply #3 of 6)

I have a north facing garden entrance courtyard planned for my new house. Sun never strikes it directly, and I really want to funnel as much of that northern light as possible down into the courtyard, so I am going to use a single flat lucite sheeting over the entry. Not sure how I am going to support it, but I prefer this to corrugated polycarbonate.

If you can foresee ever enclosing this porch, then you might want to consider using twinwall polycarbonate instead, as it's got good insulative qualities.

(post #104987, reply #4 of 6)

Thanks, all

I was actually planning on going with the multi-wall polycarbonate rather than the sheet stuff because it's a lot stronger.

(post #104987, reply #5 of 6)


I live in the NW also (Portland area) and have the same situation as you. A solid roof, even with skylights would cut out too much light for the associated rooms.

So like you,  I'm deciding on some form of "transparent roof" However, I've decided against the do-it-myself roof. I am handling the remodel to the deck it will cover (that I built),  the support structure for the roof and a railing/stair system  There are options/companies that can supply polycarbonate and glass patio roofs and even companies that offer "opening" roofs of metal or glass.

I'd also research companies that produce "sun rooms"  - you just want the roof portion not the walls. I also recall a company that specialized in the DIY projects and had some application to help design/purchase the required materials from them (search the web for polycarbonate panels)

Check out these links:




(post #104987, reply #6 of 6)

We just replaced the green fiberglass junk with polycarbonate on a North-facing side yard / dog run.  We used clear for the half closest to the house - to get more light into the bedroom - and the solar grey on the outer half - to provide a bit of protection for the plants in the height of summer.

Fast & easy to install, they even have various flashing pieces for side walls, end walls, etc.  You can walk on the roof as long as you use a scaffold-type board for support.