Attic R Factor In Nc

It also happens if you place batts rated for one thickness into a thinner cavity such as placing r 19 insulation rated for 6 1 4 inches into a 5 1 2 inch wall cavity.

Attic r factor in nc.

Insulation levels are specified by r value. 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. Insulation which is compressed will not give you its full rated r value. Add the right kind of insulation.

Based on your zone use the table to find out how much insulation you need to add if you. This can happen if you add denser insulation on top of lighter insulation in an attic. R value is a measure of insulation s ability to resist heat flow. Recommended home insulation r values.

The fenestration u factor column excludes skylights. Insulation level are specified by r value. The recommended level for most attics is to insulate to r 38 or about 10 to 14 inches depending on insulation type. The prescriptive r values for a new house in the new 2018 nc building code are as follows.

For example if you have a type of insulation that has an r value of r 5 per inch of thickness you will need a depth of 6 inches of this insulation installed in your attic to reach r 30 if you live in zones 2 or 3. R value is a measure of insulation s ability to resist heat traveling through it. 10 13 means r 10 continuous insulated sheathing on the interior or exterior of the home or r 13 cavity insulation at the interior of the. 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.

Notes from previous r value chart a. U factors and shgc are maximums. If you think you re among the 90 of us homes that are under insulated 1 performing a simple insulation inspection will help you determine your insulation needs. 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 higher the r value the better the thermal performance of the insulation. Wake county is 4a zone so walls floors ceilings and slab insulation values are unchanged from the 2012 code. The building code requires certain r values for the state based on different locations and climates. Recommended insulation levels for retrofitting existing wood framed buildings.

The shgc column applies to all glazed fenestration. These r values are a sum meaning this should be the total r value once you add up the entire depth of insulation. R 19 on floor system garage ceiling. Having the correct amount of attic insulation can help you maintain a comfortable temperature throughout your home and help save money on your energy bills plus prevent major issues like ice dams in the winter.

Roofs or ceilings need to be insulated to a minimum of r 38 in zone 3 or r 49 in zone 4. The map below shows the most cost effective levels of insulation for the different climate zones in the u s.