What R-Value should be in ceiling?

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.

What is an R-Value and what value should be in the attic?





Recommended insulation levels for retrofitting existing wood-framed buildings

Zone Add Insulation to Attic
Uninsulated Attic Existing 3–4 Inches of Insulation
1 R30 to R49 R25 to R30
2 R30 to R60 R25 to R38
3 R30 to R60 R25 to R38

What should attic insulation level be?

The higher the R-Value, the better the thermal performance of the insulation. The recommended level for most attics is to insulate to R-38 or about 10 to 14 inches, depending on insulation type.

Why is a higher R-Value needed in the ceilings?

R-value measures how well building insulation can prevent the flow of heat into and out of the home. Higher R-value means greater insulation performance, and thus more savings on your next heating and cooling bill.

Can you have too much insulation in your attic?

It’s possible to over-insulate an attic as too much will cause moisture buildup and eventually result in mold. Eventually, adding more insulation leads to diminishing returns in trapping heat as well.

Is R30 insulation good for attic?





The average recommended level is 14 inches of R49. In Zone 2, the average minimum requirement for attic insulation is 9 inches of R30 fill. The average recommended level is 17 inches of R60. In Zone 3, the average minimum requirement for attic insulation is 9 inches of R30 fill.

Is R60 attic insulation worth it?

Recommended R-Value Varies by State
You need exactly as much as the area you live in determines. Here, where temps get pretty hot for much of the year, attics should have from R30 to R60 (average is R38). Those living up north want anything from R49 to R60. This helps insulate against the extreme cold weather.

Does stacking insulation increase R-value?

DIY Frequently Asked Questions / Can I stack insulation to get a higher R-value? Yes. For example, two R-19 batts can be stacked on each other to create R-38 insulation. You also can add loose-fill insulation on top of a bottom layer of batts.

How many inches is R38?

Fiberglass Chart

R-Value Thickness Bags / 1000 Sq Ft
R49 16.25” 22.6
R44 14.75” 20.1
R38 12.75” 16.8
R30 10.25” 13.0

Will adding more insulation attic make difference?



According to the Department of Energy, properly insulating the attic can save 10 to 50 percent on a typical heating bill. In the Washington area, there are many styles of homes and roofs, but typically most have some degree of attic space, either walk-in or crawl space.

Should you insulate the attic ceiling?

Proper attic insulation can also keep your roof in better condition by helping to prevent ice dams and condensation. Your building codes may require you to have a certain quality of insulation. However, installing even better insulation is to your advantage and your roof’s advantage.

Should I insulate between the rafters in my attic?

Insulating between rafters will do no good, because the attic should be ventilated, and the rafter insulation would be between two unheated spaces. You can add insulation to the floor; the more the merrier. Just don’t put it in the eaves. Also, make sure the attic is well ventilated.

Should I insulate my attic floor or ceiling?



roof insulation is no-contest. The floor wins every time. Insulating the floor is standard practice for an unfinished attic space. The exception to this rule takes place when families opt to convert an unfinished attic space into something usable or livable.

Is it better to insulate ceiling or roof?

If you are deciding between insulating the roof deck or the ceiling, Insulating your ceiling should be the priority. Not only is it easier but ceiling insulation is beneficial in a number of ways: Keeps the temperature in the building regulated. Saves on energy costs.

Can you put insulation directly against roof?

All About Roof Flashing
Experts usually advise builders that you can’t install fiberglass insulation directly against the underside of roof sheathing.

Should attic insulation touch the roof?

Attic insulation should not touch the roof. Although it can be tempting to over insulate, resist the urge. Too much insulation hinders airflow and can keep excess moisture from escaping, especially in attics.

How much space should be between ceiling and roof?



Builders aren’t bound by standard rafter spacing measurements. But they do tend to space rafters in one of several industry-standard increments, typically either 12, 16 or 24 inches apart.