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Keep Your Home Warm And Energy Efficient: Install Wall Insulation

Has your house been feeling a bit drafty lately? Are your heating bills skyrocketing? If so, you may have an insulation problem. Proper insulation is necessary to maintaining a warm and energy-efficient home. In particular, is it important that both your interior and exterior walls are well-insulated, to prevent you from feeling cold during those winter months. Wall insulation is fairly straightforward to install, so, if you feel like saving a little money and spending a little time working with your hands, you may benefit from installing your own wall insulation. Here are some of the basics that you will need to know when it comes to installing wall insulation.


Choosing the Right Insulation

The most important part of insulating your home is making sure that you choose the correct home insulation. The right insulation will reduce those drafts and keep the heat in your home.

All types of insulation are measured according to R-value. R-value is a measurement of how heat resistant a certain insulating material actually is. The higher the R-value of your insulation, the better defense you will have against drafts and heat loss. Contrary to popular belief, R-value is not based on the thickness of your insulation, but instead, is based on the density of your insulation. When insulating your walls, you will need an R-value of at least R-11. However, R-values do depend upon the state in which you live, so be sure to check local building codes.

Types of Insulation
There are actually five main types of insulation to choose from. Some of these are harder to install than others and certain types are more suitable to specific areas of your house.


  • Batts and Blankets: Batts and blankets are the most popular type of home insulation. They are usually made of fiberglass or mineral wool, that has been spun into a long mat. They are often used for ceiling, attic, and basement insulation, because they are easy to install and provide excellent R value. Fiberglass insulation batts usually come in pre-cut pieces that range from four to eight feet in length. Insulation blankets come in long rolls and are cut on-site to fit certain spaces.
  • Loose-Fill: Loose-fill insulation is a fluffy, granular material made out of cellulose fiber, fiberglass, or mineral wool. It looks a lot like snow, and is blown into cavities in your house using special equipment. It is often used in attics and ceiling cavities and is beneficial because it doesn’t have to be cut to fit tricky spaces.
  • Spray Insulation: Spray foam insulation is made out of urethane or cellulose and is also applied using special equipment. This type of insulation is usually used for open attics and is best applied by a professional.
  • Foam Insulation: Foam insulation comes in rigid boards and offers good resistance to cool and hot air. It can be installed in walls and floors, but it does contain chemicals known as CFCs, which are damaging to the environment and ozone layer.
  • Reflective Insulation: Reflective insulation is made out of separate layers of specialized foil materials. These foil layers are installed to create a reflective space in walls and attics, which helps to keep heat in your house. Foil insulation is not commonly used and requires special installation.


When installing your own wall insulation, it is usually recommended that you use batt or blanket insulation.

Vapor Retarders
It is necessary to protect against future moisture development when you install wall insulation. The air inside and outside of your house can create moisture droplets inside of your walls, which in turn can affect the performance of your insulation. For this reason, you will need to install a vapor barrier on all of your exterior walls. Vapor barrier is simply a plastic sheet, usually 6 millimeters thick, that you cover your insulation with. In cool climates, vapor barrier is installed on the heated side of the wall; in humid climates, the vapor barrier is installed against the unheated surface of your wall.


Preparing To Insulate

Before you can begin to insulate your walls, you will need to get together the right tools for the job. You will also have to do a little bit of preparation work before you install that insulation.

Tools for Insulation
Be sure to collect all of these tools before you begin to insulate:


  • utility knife
  • straight edge (to cut the insulation against)
  • staple gun and staples
  • duct tape
  • tape measure


You will also need safety equipment:


  • safety goggles and gloves
  • long sleeved shirt
  • hard hat or baseball cap
  • dust respirator


Preparing the Walls
You will need to check all of your exterior walls for any cracks or crevices before installing the insulation. Heat can escape through these cracks making your insulation less effective. Check for cracks around all pipes, wiring, and ductwork. Repair cracks with a simple epoxy filler as recommended by your local building code.


Installing the Insulation

Once you have chosen your insulation and collected your materials, you can begin to install the insulation. It should take about three hours to install 100 square feet of insulation. These steps will take you through the proper installation of batt or blanket insulation.

1. Put on all safety equipment before opening the insulation from its packaging.

2. Measure the spaces between individual wall studs. You will cut your insulation to fit into the spaces between the wall studs.

3. Lay the insulation, facing side up. Using your straight edge and utility knife, cut the insulation to size. It is a good idea to cut insulation one inch wider and longer, in order to ensure a tight fit in the walls.

4. Peel back the facing at the top and bottom of the cut insulation about one inch. This will allow you a place to staple the insulation in.

5. Push the piece of insulation into the wall, starting at the top of the stud. The insulation should fit snugly. Staple in place.

6. Continue cutting each piece of insulation and install them into the walls.

7. When inserting installation behind pipes, do not stuff the insulating in. Instead, cut the insulation so that it is less thick. This will prevent any heat buildup that may result in a fire.

8. If there are any heat-producing elements in your walls (such as electrical outlets) cut the insulation so that there is at least three inches of space between the insulation and the element. This is required by code, to prevent fires.

9. Once the insulation has been installed, install the vapor barrier. This vapor barrier can be stapled to the top of the insulation, and should completely cover all insulation. If any rips or tears pierce the vapor barrier, cover them with duct tape.