How would you create this type of roof/ceiling?
A few months back I solicited feedback on a stock plan we were considering for our mountain-side lot. That post prompted us to restart the design process to create a custom layout that would better fit the location. The inspiration house we are working off of has a killer ceiling detail that I’d like to incorporate, but I’m not sure about the best approach. Maybe the GBA community can contribute some ideas or recommendations.
I’m attaching three photos that show the exposed joists, collar ties, and (I guess) rafter ties we’d like to replicate. Would it be better to build this as a real structural roof assembly or put the structure above and then treat the exposed part as decorative elements? I’m leaning toward the latter since it will make air sealing easier.
The house is only about 20 feet wide (more open than not), so we probably could could use parallel cord trusses to carry the load and then treat the “attic” as an unvented (r-38) space. I’ve found a couple of sources for the grass cloth BTW (the real stuff and not vinyl-back wallpaper).
Thoughts? Community restrictions mean the exterior is going to be pretty ho-hum. We’re hoping to make up for that on the inside.
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Replies
Steve,
I've built them the way they are traditionally done, with a 2"x6" t&g deck over the rafters and foam ab0ve that. The problems I encountered were:
- You are framing load-bearing elements that will also be finished surfaces, so fasteners, dings, stains from wetting etc., all have to be dealt with later which is very time consuming - and you wouldn't typically use nice lumber for those elements unless they were going to be seen.
- The problem of how to air-seal the t&g decking extending out to from the overhangs.
- Inverse roofs, with the insulation above the deck, mean construction has to take place during good weather. Something that would preclude building here for a good portion of the year.
I'd aim to recreate the look you want once the underside of the trusses or rafters was complete. That also frees you to use whatever span you want based on aesthetics, rather than load-bearing considerations.
Thanks, Malcolm for confirming my suspicions about how to go about this. Treating the ceiling as a decorative element will make it easier to line up a good finish carpenter for the work as well.