Type and material of your insulation.
Insulation value for nc attic insulation.
Houses in a cold climate should have a minimum of r 49 in the attic which is equivalent to approximately 16 of fiberglass insulation.
Square footage of your attic.
R value climate zone chart for wall attics and floors.
Achieving greater r values in attics the higher the r value the better the thermal performance of the insulation.
Warmer climates only require an r 38 or higher or about 12 or more.
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.
According to home advisor insulating your attic can cost between 1700 to 2100.
R 15 on exterior walls.
Contractor or insulation installer s fee.
Almost all insulation products have to tell you their r value pipe and duct insulation are the only exceptions.
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.
Wake county is 4a zone so walls floors ceilings and slab insulation values are unchanged from the 2012 code.
All new construction in the usa and canada today must meet certain minimum r values depending on what climate area of the country you live in.
Floors over unheated spaces need to be insulated to a minimum of r 19 in zones 3 and 4.
Existing 3 4 inches of insulation.
Recommended insulation levels for retrofitting existing wood framed buildings.
First things first you need to go up into your attic inspect the condition of the insulation and calculate the current level of insulation.
Walls need to be insulated to a minimum of r 20 if the insulation is between the studs or r 15 r 5 if the insulation is a combination of insulation between the studs and a continuous layer of exterior insulation in zones 3 or 4.
The prescriptive r values for a new house in the new 2018 nc building code are as follows.
Many homes have no insulation at all because building codes didn t even require insulation prior to the mid 1970 s.
The main factors that impact the cost are.
Add insulation to attic.
R 38 for the ceiling attic.
Inspecting your attic insulation.
Duct wrap is covered so if you re looking at insulation with an r value of 38 from company a and insulation with an r value of 38 from company b you ll know the two products offer the same level of insulation.