Then use the numbers in the chart at right to estimate its r value.
Compressed insulation attic.
Compressing r 19 insulation typically 6 thick into a 2x4 stud cavity that is 3 deep.
If it is cold storage just compress the insulation the difference will not be noticeable.
Then there are lots of questions that need answers about permits structure air barrier insulation and roof venting.
Simple thermal analysis reveals that if you have 5 missing insulation in an attic bare sheetrock you ll have a slightly more than a 54 drop in r value.
If your new subfloor is part of a plan to make the attic into living space.
For wool types of insulation fiberglass mineral wool steel real wool etc while it varies based on material this is typically much denser than we are able to get it via compression on the job site.
When you compress fiber glass batt insulation the r value per inch goes up but the overall r value goes down because you have less inches or thickness of insulation.
Grab a tape measure and a flashlight to see what kind of insulation you already have in the attic and how deep it is.
Some types of insulation are found in older homes and some of them may no longer be used.
There are different types of attic insulation and they each have their pros and cons.
These thermal defects undermine the r value of your attic insulation.
Pull up and dispose of any material that s compressed water stained or moldy it s useless.
Always wear a mask.
R value simply means resistance to heat flow.
If you want to know how to get raccoons out of the ceiling the same sort of principles apply.
This guide to proper attic insulation includes tips on vent areas gaps right side up puckers loose or compressed insulation animal nests mold mildew and rusty nails.
We can compress insulation and increase the performance of it right up to the point where the main mode of energy transfer is through the material of the insulation itself.
Install the r30 unfaced batts insulation for your attic projects.
When compressed to less than its labeled thickness glass fi ber insulation will experience a reduction in r value.
Courtesy of department of energy.