Fiber Cement Siding R Value

Foam thicker than a half inch will yield even higher r values.

Fiber cement siding r value.

Standard vinyl siding has an r value 6. Adding foam back vinyl siding leaves fiber cement in the dust as that has at minimum 1 8 r value. Asbestos lagging and paste will have a lower value. That s a little less than you ll get from vinyl siding which is rated as r 0 61 but the.

As we said before the r value measures the thermal resistance of a material. Hardiepanel siding cempanel siding. This means as a stand alone product fiber cement isn t going to add much insulation to your home. Underlayment material even a foam board doesn t offer much extra and would be applicable to both materials.

Asbestos loose packed fibers powder. Fiber cement siding doesn t add much insulation to your wall system measuring in at a mere r 0 50. R value see table 2. Esr 1844 noncombustibility see page 1 section 3 1 flame spread and smoke developed see page 1 section 3 1 1 hour fire walls see page 2 section 4 3 design wind loads see page 4 5 table 4 r values see page 3 table 2.

Thermal conductivity k 0 15. When vinyl siding is optionally insulated it can achieve r 2 values and even greater. Asbestos cement board r value. Because vinyl siding is thinner than fiber cement siding it can better accommodate insulation beneath its surface.

Half inch thick rigid foam insulation has an r value of r 2 to r 3 5. While fiber cement siding is energy efficient vinyl siding has the potential for this too. Asbestos cement shingle siding. Adding inch of rigid foam insulation r 2 in this example will increase a 2x6 stud wall from an effective r 15 to an effective r 17.

According to table 5 1 of the ashrae fundamentals handbook fiber cement has an r value of 15 better than brick and stone but lower than vinyl at r 60 wood at r 81 and insulated vinyl siding at r 2 0 3 5. For instance if you have a material with an r value of 12 attached to another material with an r value of 3 then both materials combined have an r value of 15. That means you ll need to use a superior grade of insulation inside of your walls attic and crawl space to ensure that your home is up to code in this regard. This beats fiber cement which has an r value of 5 at most.