Roof Framing on a Woody

[jpenning]

Greeting again, Fellas.

Got another quick question for ya (or maybe someone can point me in the right direction). My tear is going to be wood sides and top. The walls are 3/4" Birch (non-insulated). The exterior will be coated w/ 3+ coats of spar varnish. Is this sufficient for the elements? Also, is it ok for the roof to be 1/8th birch ply, 2x2 spars and another 1/8th birch ply or do I need to go with 1/4th for the top roof section? I am trying to save on some weight (man, those walls are heavy).

Thanks for any help!

[Steve Frederick]

I would feel comfy with the roof built as you indicated. After all, 1/4" is 2@ 1/8" If you could bond the layers together, you would have an extra-strong roof. That's the way I build, so it must be right!! The curved ply is very strong! Three coats of spar is good for protection too!

[JunkMan]

Speaking of roof framing, does anyone have any close up pics of how the roof and side walls mate up when you build using a sandwich type wall? What I am trying to figure out, is if you make the outer skin larger than the inner skin. Also wondering if you do anything special to attach the inner ceiling to the walls other than just attaching it to the cross members. I'm thinking that there needs to some type of "edge" on the inside of the wall to attach the ceiling to.

Jeff

[Steve Frederick]

Jeff, I'm a heretic! I build the roof so that if interlocks the walls.
I build the wall so that there is a ledge at the roof line. Fasten the roof liner on top of that ledge, frame the roof on top of that, Insulate, and skin the roof. You'll get a nice joint at the wall cieling line. You won't torture yourself trying to get that headliner up inside the cabin...It' just a nicer way! IMHO!!

This is a view before skinning the forward section of the cabin cieling. See how the headliner rests on the framing of the insulated wall. I glue and screw the roof struts to the same ledge, no screws from the outside, nice for a woody! Also, the seam in the headliner falls on the forward closet wall.

[JunkMan]

Steve,

That is exactly what I was thinking of. Glad to hear it works! I have looked at a lot of pics where it looks like the interior ceiling went on after the framing (usually on a 3/4" plywood side wall, not a sandwich wall), but your way looks easier, and you don't have to be as exact on the cut .

What do you put over the insulation and roof struts, 1/8" or 1/4" plywood? I'm thinking about 2 layers of 1/8", glued together, so it will roll easily, yet still be strong.

Jeff

[Steve Frederick]

2 layers of 1/8", glued together, so it will roll easily, yet still be strong.

Exactly! 2 layers, glued together. I went nuts though, and covered the roof in Cedar!!

[JunkMan]

Steve,

The cedar looks great. I would love to build a "stripper" kayak some day. Having a matching "stripper" TD would be excellent.

Jeff

[Scooter]

Steve, I agree your tear looks great. It's on my short list of tears I'd most like to see in person someday.