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Chris Friesen

wrote:

The problem is that the 2' x 4' rafters aren't deep enough for adequate
insulation. So here are my choices, and I need some advice from someone
knowedgable.

Do you have a flat or cathedral style ceiling?

If you have a flat ceiling, what about just putting R38 worth of
insulation in the ceiling and having it stick up into the attic area?

With a cathedral ceiling you have a bit more hassle, since you don't
want to put insulation right up against the bottom of the roof--you
generally want airflow there. You can add furring strips to the rafters
(to allow for thicker batts), add rigid foam, or use a combination of
the two techniques.

In any case you'll want to vapour-barrier the warm side of the
insulation, and ensure that the attic has sufficient venting/airflow so
that the roof itself stays cold in winter. This will minimize the
chances of ice dams.

Chris