Insulation

Insulation is ultimately the most important component of any heating system. Whether you’re using a furnace, electric wall heaters or radiant heating panels, a properly insulated space is going to make your heaters work a lot better and ultimately save you money.

Understanding R-Values

Insulation r-values can be confusing if you don’t understand them. Put simply, r-values are a rating of how much thermal resistance insulation has. Insulation with a high r-value rating will resist heat rather than conducting it. What this means in layman’s terms is the higher the r-value ratings on your insulation, the better it will retain heat and maintain temperatures.

How Much do I Need

When it comes to insulation we typically tell people that more is better. Having more insulation and higher R-values will help retain warm temperatures in the winter and cool temperatures in the summer so you’re saving money on energy costs year-round.

Click here to find the insulation minimum requirement in your state and county.

45In the average American home, 45 percent of the utility bill can be attributed to heating costs. With proper insulation, you can decrease your heating bill while increasing the warmth and comfort in your home.

There are some general guidelines that outline how much insulation you should have in your space. Things like your location, elevation and average temperature range will play a big factor into how much you should insulate. A home in Phoenix, AZ is going to require less insulation than one in Buffalo, NY. The following map and chart from the U.S. Department of Energy provide a good guideline for how much insulation you will need in your area. You can also click here to find the minimum insulation requirement in your state and county.
Insulation Chart Map

 

Types of Insulation

The market is so flooded with options for insulation that deciding on one can be a daunting task. However, exploring the features and benefits of each can help narrow the choices down. Ultimately, it will come down to what will fit in your space, your budget and what R-values you need. Generally speaking, we suggest getting the most insulation you can. When it comes to insulation, more will always help maintain your desired temperatures and keep your heating bills down!

BattsBatts – Batts are one of the most common types of insulation due to their ease of installation and relatively low cost. They are made to fit between joists and rafters. Batts insulation typically comes in blankets or will and can be made of a variety of materials such as fiberglass, wool, cotton and even soy. It’s a great choice for DIY projects.

R Values – 3.0-4.0 per inch (Depending on Material)

Common Uses – Walls, Foors, Ceilings

 

Blown In InsulationBlown-In – Blown-in or loose-fill insulation consists of fiberous strands of fiberglass or cellulose that are blown into ceilings or walls with a special machine. This type of insulation can be installed as a DIY project with rented equipment or you can hire a professional.

R Values – 2.2-3.8 per inch (Depending on Material)

Common Uses – Walls, Ceilings

 

 

Spray InsulationSpray Foam – Spray Foam insulation is a type of liquid that expands into a foam when applied. It can be sprayed into walls, floors and ceilings and will fill those hard-to-reach nooks and crannies. While spray cans of foam insulation can be bought for insulating very small areas, such as around pipes and windows, professional installation is needed for larger applications.

R Values – 3.5-6.5 per inch (Depending on Material)

Common Uses – Walls, Foors, Ceilings

 

SIPSStructural Insulated Panels (SIPS) – SIPS consist of an insulating material, such as foam, sandwiched by particle board sheets. These sheets typically come in 4’x8’ configurations and are most often used for new construction. They are great due to their ability to insulate an entire wall, but can be expensive to install and to not lend well to remodels or retrofits.

R Values – 3.8-7.7 per inch (Depending on Material)

Common Uses – Walls, Ceilings

Savings Calculator

To get an idea of how much you could save by adding insulation plug the variables for your space into the calculator below. Adding insulation almost always pays off in the long run and you’ll enjoy a warmer home to boot!

NOTE: This calculator is based on an equation from the U.S. Department of Energy. It has been modified by Gary Reysa, an engineer who runs Build It Solar. It is intended to be a general estimate based on average variables so your results may vary.

Area to be upgradedSquare FeetEnter the total surface area of the area where insulation is to be upgraded.
Heating Degree DaysHDD (Fahrenheit)Copy and paste the annual total HDD for your ZIP code from the bottom of this page
Current R ValueUS R Value
New Total R ValueUS R Value
Pick your fuel type below — Then, enter the correct fuel cost for your area, and furnace efficiency for your particular home.

(Note fuel costs vary greatly. Contact your local fuel provider for current prices and change the default amount for the most accurate estimation of potential savings.)


Natural Gas

Fuel Oil

Propane

Electricity
%
Click Calculate button to update fuel saving
$ Saving per yearDollarsThe dollar saving in fuel cost for the
first year.
$ Saving for 10 yearsDollarsThe dollar saving in fuel costs for the
first 10 years, assuming a 10% increase in fuel cost each year.

Where to Insulate

For optimal efficiency, your home should be insulated from the attic ceiling to the basement floor. For tips on where to concentrate insulation consider this graphic from the Department of Energy.
where_to_insulate

  • 1: Unfinished Attic – Insulate between and over the floor joists and around attic access door (1a).
  • 2: Finished Attic – Insulate between studs of knee walls (2a), between studs and rafters of exterior walls (2b), and ceilings with cold overhead spaces (2c). Extend insulation into joist space (2d).
  • 3: Exterior Walls – Insulate walls between rooms, garages, storage areas (3a); above ground level foundation walls (3b); foundation walls in heated basements (3c).
  • 4: Floors – Insulate floors above cold spaces such as vented crawl spaces and unheated garages. Also insulate floors cantilevered beyond the exterior wall below (4a); slab flors built directly on the ground (4b); foundation walls of unvented crawl spaces (4c). Extend into joists (4d).
  • 5: Band Joists
  • 6: Windows & Doors– Seal and caulk around windows and doors.

Seal Air Leaks

Another key component to properly insulating your home involves making sure it’s well sealed. Air leaks around plumbing vents, doors, windows and other culprits allow cold air to enter, and heated air to escape your home. By sealing these areas, you can improve your heating efficiency. The following image from energy.gov shows some areas prone to air leaks.

Sources of Air Leaks in Your Home. Areas that leak air into and out of your home cost you a lot of money. The areas listed in the illustration are the most common sources of air leaks.

Do a Blower Door Test

diagnostic_toolsYou can test for air leaks in your home by doing a blower door test. A professional energy auditor will place “blower door” in your doorway. This is an instrument containing a fan that pulls air out of your home and a series of gauges to measure air pressure. This creates a pressure gradient between your home and the air outside, which allows the auditor to pinpoint air leaks in your home. This is illustrated by the graphic to the right, provided by energy.gov.