While most people would be throwing some OSB on the roof at this point, Faith and I really wanted to leave the rafters exposed on our frame. In order to do this, we needed to install the finished ceiling on the rafters first before we added rigid insulation and the shingles.
In most timber frames today, enclosure methods are commonly dried-in with insulated panels that are prefabricated. While there is much to be said for this method, they are certainly not cost effective. Some people go through the effort of making their own panels, but that requires very accurate rafters and it’s difficult to get a tongue and groove finish on the ceilings when it’s all said and done.
I decided that I would simply build up the roof starting with the tongue and groove, then adding rigid insulation, then a layer of OSB, and finally the shingles. This isn’t the time effecient method, but it is certainly the cost effecient one.
I ordered the tongue and groove planks from Home Depot seeing as their price was significantly lower than any other source I found. At the time of this writing, one 1″x6″x8′ piece sells at $4.25. So in the tongue and groove, I had around 1200 dollars.
This is half of what I needed, sitting in my woodshop.
It was important to keep the stuff very dry. The planking was kiln dried, so any moisture from rain would really make the pieces swell and would make fitting them near impossible. This also proved to be troublesome when it came to installing the planks because the process was so slow. With the large amount of rain we had in the past couple weeks, I was covering my progress with tarps almost every day.
Another challenge posed to me was the pitch of the roof. As I’ve said before, the roof is on a 12/12 pitch and is impossible to scale without additional support. I had to work from the top, down so that my pieces at the top would run parallel to one another. If I had started at the bottom, and didn’t stay perfectly square, the pieces at the top would have to be ripped at unequal proportions. Working from the top down kept everything symmetrical and gave me a place to put my footing as I came down the roof.
To scale the roof at first, I placed 2×4’s on the outside of the rafters spaced as far as I could stretch and climbed up. I removed them as I came down the roof with the planking. I had a safety harness for this endeavor, but I still had plenty of uncomfortable moments. Unfortunately, I didn’t get many pictures of the process since I was more concerned with keeping my balance.
As I got towards the bottom, I found out quickly that I was going to need a scaffolding running the length of the eaves to make things a little easier. Pa helped rig one up on each side with two inch rought cut poplar. It makes things significantly more efficient.
Since my rafters are four inches wide, I was able to have plenty of room for error when installing the pieces. The butt joints were on the outside of the rafter, so the planking looks seamless from the inside.
Faith and I liked the look of the solid piece with no bead on the underside of the plank better, so we put the extra bead pattern on the outside. Looking so nice in the end, it was a shame to cover even that side up, but the underside looked incredible.
I have a couple places at the ridge of the roof where there is a bit of a gap, but I’ll cover those with some corner trim in the end.
Once I had the planks up, I was able to lay a layer of felt roofing paper to give me a temporary roof and to give a black back drop in case any holes or gaps were showing in the tongue and groove. This, too, proved to be difficult since I had no place to get my footing now that the 2x4s were gone. So I fabricated a “chicken ladder” out of 2x4s that hooks over the top of the ridge so that I could scale the roof with ease.
When the weather stays consistently dry, I’ll start with the rigid insulation, OSB, and shingles. In the meantime, I’ll be framing windows so that I can close in the walls.