1.   And would putting new plasterboard over the rigid insulation be OK?

2.   Another technique is to install the rigid insulation as sheathing, not using wood sheathing at all.

3.   Cut out the ceiling and put in rigid insulation.

4.   For the bottom of the sloped ceiling, you could put the rigid insulation on that knee wall and finish off with plasterboard.

5.   If you can see the space, you can cut the rigid insulation to fit and slip it in place.

6.   Other areas are highly insulated, too, including the studded basement walls, and rigid insulation under the concrete basement slab.

7.   Rigid insulation is good in certain applications such as places where fiberglass or cellulose is not practical to install.

8.   Rigid insulation is also a vapor barrier.

9.   This is usually done by installing a type of rigid insulation that is sold in home centers and building materials dealers.

10.   Would rigid insulation on that slanting ceiling be adequate?