When using fiberglass insulation the pink stuff the attic roof rafter will need to be at least 16 deep.
Attic insulation in 2x4 ceiling joist space.
How to reinforce an attic floor with sister joists.
Also remove any blocking or bridging between the joists as applicable.
Enjoy better floor to floor climate control in your home by installing ceiling insulation.
Sistering 2x6 joists next to your current 2x4 joists will simply give you a new floor height of 5 1 2 inches as opposed to the current 3 1 2 inches.
How to increase the interior ceiling joist for r38 insulation.
Always cover the tops of the ceiling joists to make sure the insulation is deep enough to reach your target r value and to prevent thermal bridging the heat loss that occurs through the wood framing.
Current insulation code requires r 49 insulation in the ceiling.
Pull out all insulation and any debris from all of the joist spaces so you can see the full length of each joist including where it meets the exterior walls.
Now that you understand insulation r values you can make sure your home is properly insulated.
They are directly below the roof sheathing and are were insulated with fiberglass batts stapled between the 2x4 rafters.
There are some unfinished crawl space areas in the corners on the upper floor.
I have a 1925 bungalow in michigan climate zone 5.
Work from the perimeter of the attic toward the door or hatch so that you don t trample all over the insulation you just put in.
Option 2 has the benefit of preventing any thermal bridging via the ceiling joists.
Over the past several years there has been an increased focus on making insulation codes more stringent.
Put insulation meant for 2x4 framed walls between the joists which will be the same height as the joists then lay a perpendicular layer of attic insulation maybe r 30 on top of them.
Clear the joist spaces.
If you want to put down flooring in your attic and want more insulation underneath that floor then you need to increase your joist size.