R19 Or R30 In Attic
Drill holes in the sheathing and blow insulation into the empty wall.
R19 or r30 in attic. Wall insulation whenever exterior siding is removed on an. So if r 19 is designed for 3 1 2 and r 30 is designed for 5 1 2 and you still need an inch or so for ventilation of the plywood you need to have at least 10 rafters. In florida 2 000 sq ft ceiling r19 to r30 reduces btus by 2 002 btus with r4 duct in the attic. Find your zone on the map and then use the chart to determine the level of insulation you need to properly insulate your attic walls floors and crawlspaces.
I believe crushing the insulation together decreases it r value. Don t stuff r 30 into a space that just fits r 19 5 1 2 because you will lose efficiently if you do. If you use the attic for living space you should insulate the ceiling of the attic if not then do the ceiling of the house itself. That said use as much as you can.
R19 r30 r21 fiberglass insulation insulation the home depot.