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.
Insulation value for nc attic insulation.
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.
Wake county is 4a zone so walls floors ceilings and slab insulation values are unchanged from the 2012 code.
First things first you need to go up into your attic inspect the condition of the insulation and calculate the current level of insulation.
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.
R 15 on exterior walls.
Achieving greater r values in attics the higher the r value the better the thermal performance of the insulation.
Type and material of your insulation.
The main factors that impact the cost are.
According to home advisor insulating your attic can cost between 1700 to 2100.
Add insulation to attic.
R 19 on floor system garage ceiling.
Almost all insulation products have to tell you their r value pipe and duct insulation are the only exceptions.
The prescriptive r values for a new house in the new 2018 nc building code are as follows.
Square footage of your attic.
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.
Recommended insulation levels for retrofitting existing wood framed buildings.
R 38 for the ceiling attic.
Houses in a cold climate should have a minimum of r 49 in the attic which is equivalent to approximately 16 of fiberglass insulation.
Many homes have no insulation at all because building codes didn t even require insulation prior to the mid 1970 s.
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.
R value climate zone chart for wall attics and floors.
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.
Inspecting your attic insulation.