In article , wrote:
My house is elbow shaped. Kitchen, den, living room on one side of the
bend and bedrooms, baths on the other.
The floor joists under the bedroom side are 2x8 12" on center. I am
cutting a 23" wide roll of insulation in half lengthwise to insulate
under the house. This gives a tight fit to the insulation.

However under the den side of the house, the joist spacing is 20" on
center. I have a 19" space to fill and insulation at Lowe's, Home
Depot only comes in 15", 16", 23", and 24" widths. I don't
particularly want to use the 23" rolls since that would be a waste of
4" from each roll.

Does anyone have any ideas of how to efficiently fill this space?

4x8 foot sheets of solid insulation. Cut them across the 4 foot side
in 19 inch widths. This will give you five pieces of 4'x19" insulation.
Tape the joints with aluminum tape. I used two inch thick foam with
aluminum on both sides when I remodeled my kitchen. Cuts easily with
a handsaw or a radial arm saw. Dust is nasty so wear a mask if you
use a power saw.


--
"De inimico non loquaris sed cogites."