Compressed Attic Insulation

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.

Compressed attic insulation.

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. There was no plywood up there plus it looks like the insulation is not uniformly compressed. Of ventilation air space between the insulation and roof deck.

R value simply means resistance to heat flow. Insulate the skylight passages. Begin by sealing all air gaps in your attic. There is a path down the center of the attic that has the top 6 inches of insulation above the joists that appears to have been compressed by either some one crawling across the attic or laying a piece of plywood across the joists.

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. Install the rafter vents. 0 75 6 25 0 12 or 12 compression. These thermal defects undermine the r value of your attic insulation.

Use spray foam in large. 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. 6 25 batt 5 5 cavity depth 0 75. The chart below indicates the compressed r value of standard building insulation products.

Loose fill insulation fibers are packaged in bags and blown in place to the desired depth and density using special. Designed to eliminate r value loss caused by compressing standard r 38 products in 2x12 cathedral ceiling construction. Choose your insulation type and material 1. Insulation will not slump within the cathedral ceiling cavity.

Protect the heater flue. Caulk the gaps and wrap the water lines. Check the lighting and prevent fire hazards. Step 2 take that resulting figure and divide by the thickness of the batt to determine the percent compression.

Achieving greater r values in attics the higher the r value the better the thermal performance of the insulation.