Best R Value Insulation For Attic

In particularly cold climates you might go up to r 60.

Best r value insulation for attic.

You only need four inches of r 3 5 cellulose in a wall cavity to exceed the recommended insulation level of r 13 for walls located in zone 4. The higher the r value the better the thermal performance of the insulation. Cavity wall insulation technique determining what is the best house insulation polyurethane foam has the highest r value 6 5 inch thickness of all the spray in insulation but it is also the most expensive. But newer homes in central and southern arizona are insulated to ratings of r 30 to r 38 while newer homes in northern arizona generally have attic insulation at r 60 because of colder winters.

Recommended insulation levels for retrofitting existing wood framed buildings. In general an attic s r value should be between r 30 and r 49. Therefore it needs to be fireproof. Before you ever get insulation anywhere near the attic though make sure that you get the air leakage sites sealed up.

Existing 3 4 inches of insulation. You will need a higher r value of insulation if you live in the northeast than if you live in southern california. Depending on where you live and the part of your home you re insulating walls crawlspace attic etc you ll need a different r value. Add insulation to attic.

Here are the most common insulation materials listed in order of lowest to highest r value. You can achieve better thermal performance in your attic by adding an additional layer of insulation. If you put an air permeable insulation material over a hole in your ceiling you may have comfort indoor air quality durability and efficiency problems. Recycled glass or sand that s melted and spun into fibers.

Typical recommendations for exterior walls are r 13 to r 23 while r 30 r 38 and r 49 are common for ceilings and attic spaces. However cellulose is inexpensive environmentally friendly and easy to install behind finished walls. Lighter in weight than cellulose or mineral wool but it settles more than those materials so you ve got to put in a thicker layer to get the protection you need. There are many ways to retrofit a home with fiberglass and.

Cellulose has an r value of 3 5 inch thickness. Let s say the insulation you ve selected has an r value of three per inch and. Achieving greater r values in exterior walls. It is manufactured from recycled paper.