Insulation level are specified by r value.
													
																	Minimum r value for attic. 
									
	
		
	
																	R value measures how well certain building insulation materials can resist heat. 
																	The second r value for mass walls applies when more than half the insulation is on the interior of the mass wall. 
																	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. 
																	In zone 2 the average minimum requirement for attic insulation is 9 inches of r30 fill. 
															
													
									
	
		
	
																	The recommended level for most attics is to insulate to r 38 or about 10 to 14 inches depending on insulation type. 
																	The higher the r value the better the thermal performance of the insulation. 
																	Insulation r values are minimum acceptable levels and must be determined according to ftc rule. 
																	Find out why in the seller s fact sheet on r values. 
															
													
									
	
		
	
																	The higher the r value the greater the insulation performance. 
																	Under insulated here means when compared to the minimum prescriptive wall and ceiling insulation r values found in the 2006 international energy conservation code iecc savings vary. 
																	2015 code requires walls to be insulated with a minimum of r 20 or r 13 5 13 5 means r 13 cavity insulation plus r 5 insulated sheathing. 
																	R value is a measure of insulation s ability to resist heat flow. 
															
													
									
	
		
	
																	When determining how much insulation you need don t guesstimate calculate. 
																	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. 
																	Recommended home insulation r values. 
																	If structural sheathing covers 40 or less of the exterior continuous insulation r value shall be permitted to be reduced by no more than r 3 in the locations where structural sheathing is used to maintain a consistent total sheathing thickness. 
															
													
									
	
		
	
																	In zone 1 the average minimum requirement for attic insulation is 9 inches of r30 fill. 
																	Consequently the thickness which fluctuates according to the type of insulating material must be suitable to meet the needs of r value. 
																	R value is a measure of insulation s ability to resist heat traveling through it. 
																	The average recommended level is 14 inches of r49. 
															
													
									
	
		
	
																	The higher the r value the better the thermal performance of the insulation. 
																	Know exactly how much you need with our project calculators.