We earn commissions from product referrals and completed forms.

DIY Attic Insulation: How Do You Do It?

Poorly insulated attics are one of the most common problems with homes. Home inspectors often note a lack of proper insulation. This not only makes the home less valuable, it also reduces the utility of your square footage. Without proper insulation, your attic is good for little more than storage space. 

With the addition of insulation, you can use your attic for many other purposes. Perhaps an attic conversion will add utility to your home by repurposing your attic from storage area to sitting room, bedroom, or office. If you are interested in your attic being used for something other than boxes of old books and seasonal item storage, you will need to insulate it. For the DIY crowd, there are multiple options for insulating your attic.

For most DIYers, fiberglass rolls are the most practical option. These are the long rolls of pink insulation many people are familiar with. Fiberglass rolls are not the ideal material. You may get better results with blown insulation, though this may require hiring a contractor.

If you want to DIY with fiberglass rolls, be certain to wear protective gear. The fiberglass insulation can give off tiny particles that are damaging to the skin, lungs, and eyes. Wear safety goggles, rubber gloves, and a fiber insulation respirator mask.

The job of insulating an attic can be a difficult one. It requires rolling the insulation across the entire attic and fitting it into narrow spaces.

6 Steps for Rolled Fiberglass Insulation Installation:

1. Collect Tools and Materials:

  • Putty knife
  • Utility knife
  • Rubber gloves
  • Duct tape
  • Boards
  • Fiberglass insulation
  • Respirator mask

2. Stage the Insulation

Prepare the insulation by staging it in the attic space.

3. Install Soffit Baffles

A common mistake is covering soffit vents with the insulation, which restricts air flow. By stapling the baffles to the soffit, you will avoid this mistake.

4. Laying the Insulation

Start at the area furthest from the attic access. Use the utility knife to cut the insulation to size.

5. Work Around Obstacles and Tight Corners

When you run into obstacles, such as a pipe, roll the insulation around it. Be careful to avoid stuffing insulation into tight corners, as this reduces its effectiveness.

6. Work Around Recessed Lighting

Keep insulation at least three inches from and recessed lighting.

Other Insulation Material Options – Why Blown In Insulation Is The Best Option

You have many choices when it comes to insulation. Each option has its advantages and disadvantages. Before choosing, consider why blown in insulation is so often the best choice of DIY attic insulators.

If you can afford spray foam insulation, you should probably go with that choice. This option is not for DIYers. You will have to shell out some cash for a contractor to spray foam insulate your attic. However, if you can afford it, it’s worth considering. It’s hassle free and highly effective.

Spray Foam Insulation

Spray foam provides the benefit of moving the home’s conditioned area from the living space up to the attic, just under the roof decking.  This helps tremendously if your HVAC equipment is located in the attic because your equipment and duct runs will now be protected from extreme hot and cold temperatures by the extended conditioning envelope.  

There is one caveat: If you have a roof leak, you run the risk of trapping moisture around the roof deck. This can lead to expensive repair work. However, if you can manage this risk, foam is a fantastic option, though you will pay double to triple the cost of other insulation methods. 

Fiberglass Batt Insulation

Fiberglass batt insulation consists of woven rolls of fiberglass that are easy to install.  You simply cut it open and roll the insulation out.  The disadvantage of fiberglass batt insulation for attic installment is that it has a tendency to leave gaps between the rolled pieces, so you won’t get complete coverage. This leaves areas of your ceiling with no insulation.  For this reason, I have to give fiberglass batts a thumbs down.  There are much better options.

Blown-In-Fiberglass

The majority of homes have blown-in fiberglass insulation. Blown-in fiberglass uses small pieces of fiberglass, which come in a bag and are installed with a blower machine.  The blown-in fiberglass is far more effective versus fiberglass batts, as there are no gaps in the coverage.

Blown-in fiberglass is a good option, but cellulose is often a bit better for several reasons.  

Firstly,  it does a better job at restricting airflow when you have a lot of it.  While neither material is a true air barrier (meaning it blocks airflow completely), cellulose does a better job of stopping air transfer between the living space below and the attic, provided you blow in a thick blanket of the stuff.

Secondly, Cellulose does not cause itching. Other types of insulation can cause skin irritation, which you will be glad to avoid. 

Blown-In-Cellulose

Cellulose continues to gain more popularity for new house construction.  The R-value is about equivalent to blown fiberglass, and the cost is also similar, but, as mentioned above, cellulose won’t irritate your skin. For these reasons, I recommend using blown-in cellulose.

Note: It will not hurt anything to mix the two different materials.  Don’t worry about blowing in a new layer of cellulose insulation over old fiberglass.

Insulating your attic is one of the best ways to increase the value of your home. Several methods exist that are friendly to DIYers. However, if you have the funds available, a professional spray-foam job should be considered. Spray foam provides excellent coverage while lasting a long time.

For DIYers who want the best results, cellulose often provides the best results. Besides not irritating your skin, it is DIY friendly and provides full coverage. Even if you do not convert your attic to living space, you will benefit from the drop in utility bills.

Some homeowners save as much as 50% on heating and air conditioning. That makes insulating your attic one of the most attractive DIY projects.

Leave a Comment

Your email address will not be published.