Achieving greater r values in attics the higher the r value the better the thermal performance of the insulation.
Insulation value for nc attic insulation.
R 15 on exterior walls.
Type and material of your insulation.
Square footage of your attic.
Recommended insulation levels for retrofitting existing wood framed buildings.
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.
Wake county is 4a zone so walls floors ceilings and slab insulation values are unchanged from the 2012 code.
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.
Floors over unheated spaces need to be insulated to a minimum of r 19 in zones 3 and 4.
Contractor or insulation installer s fee.
Your attic should have a certain amount of insulation in it and the recommended level of insulation for your attic is dependent on where you live.
Houses in a cold climate should have a minimum of r 49 in the attic which is equivalent to approximately 16 of fiberglass insulation.
The prescriptive r values for a new house in the new 2018 nc building code are as follows.
The main factors that impact the cost are.
Existing 3 4 inches of insulation.
R value climate zone chart for wall attics and floors.
R 38 for the ceiling attic.
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.
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.
Add insulation to attic.
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.
Warmer climates only require an r 38 or higher or about 12 or more.
Many homes have no insulation at all because building codes didn t even require insulation prior to the mid 1970 s.
According to home advisor insulating your attic can cost between 1700 to 2100.
Inspecting your attic insulation.