First you ll have to maneuver batts of insulation around the clutter of wires pipes and cross bracing in a typical basement ceiling.
How to install insulation in ceiling joists.
Hold the batts in place by stapling their paper faced vapor retarders to the lower edges of the joists.
Measure the depth of the existing insulation between the ceiling joists in the attic.
Purchase rolls or packages of insulation that will fit in the spaces between the ceiling joists.
Make sure each run contacts the insulation you installed at the header band joists.
Leave an air gap between the roof sheathing and the board.
When the basement or crawl space.
The standard width for joists is 24 inches.
If there is already insulation between the joists increase the r value by installing unfaced roll insulation right on top.
Run the unfaced strips perpendicular to the.
If your attic floor has no insulation install faced batts or faced rolls between each joist with the moisture barrier facing down against the drywall or plaster ceiling below.
Multiply the depth in inches by 3 14 to determine the r value of the existing insulation.
The ceiling joist system is typically constructed from substantial two by tens or larger dimension boards but some older homes have smaller joists.
Joist bays the open spaces between floor joists are prime hosts for insulation under specific circumstances.
If you want to install standard r 38 insulation.
Align the front of the board with the face of the rafter or joist.
Press the cut insulation board to fit between the rafters or joists.
How to install insulation between floor joists.
If using faced insulation keep the paper vapor retarder facing up and against the subfloor.