Best R Value Insulation For Attic

The higher the r value the better the thermal performance of the insulation.

Best r value insulation for attic.

Achieving greater r values in exterior walls. Loose fill cellulose is rated between r 3 2 and r 3 9 per inch making it one of the least efficient insulation materials available. 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. You can achieve better thermal performance in your attic by adding an additional layer of insulation.

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. Therefore it needs to be fireproof. Let s say the insulation you ve selected has an r value of three per inch and. 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.

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. There are many ways to retrofit a home with fiberglass and. In particularly cold climates you might go up to r 60. It is manufactured from recycled paper.

Add insulation to attic. You will need a higher r value of insulation if you live in the northeast than if you live in southern california. Your home s age if your home is more than 10 year old you likely need more insulation. Recommended insulation levels for retrofitting existing wood framed buildings.

Where you live different climates require different insulation r values. Recycled glass or sand that s melted and spun into fibers. Cellulose has an r value of 3 5 inch thickness. However cellulose is inexpensive environmentally friendly and easy to install behind finished walls.

Before you ever get insulation anywhere near the attic though make sure that you get the air leakage sites sealed up. In general an attic s r value should be between r 30 and r 49. Here are the most common insulation materials listed in order of lowest to highest r value. 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.