Compressing Insulation In Attic

Blow in insulation until the hopper is empty.

Compressing insulation in attic.

Subtract the cavity depth from the thickness of the batt in inches. 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 installed in framing cavities with a depth that is less than the labeled thickness of the insulation. Then pivot in place and do the same thing to the other side.

If you know you aren t going to convert the attic in the future that leads you one direction compressing the insulation is fine maybe you don t care so much about head height and can add some more thickness to improve the insulation etc and if you know that an attic conversion is viable and that you are likely to want to pursue that in the future you can plan accordingly. 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. Let s look at an r 19 batt in a 2x6 cavity step 1. 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.

When compressed to less than its labeled thickness glass fi ber insulation will experience a reduction. Yes the compressed r value can be estimated using the following method. Lay a two by four on top temporarily compressing the insulation to a manageable. For every x the insulation material is compressed the r value decreases by approximately one half of that percentage or x compressed.

To cut blanket style insulation place the product over a piece of plywood with its paper or foil side down. These thermal defects not only undermine the r value of your insulation but they also make rooms uncomfortable and increase your utility bill. Achieving greater r values in attics the higher the r value the better the thermal performance of the insulation. There was no plywood up there plus it looks like the insulation is not uniformly compressed.

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. More insulation installation tricks and tips work from the perimeter of the attic toward the door or hatch so that you don t trample all over the insulation you just. The chart below indicates the compressed r value of standard building insulation products. R value simply means resistance to heat flow.

For the center areas hold the hose level and blow in insulation evenly until you ve reached your level lines photo 6.