Fiberglass Insulation: DIY Vs Professional Installation


Insulation is an important part of any home construction. It helps to control the transfer of heat from inside the house to the outside and vice versa. While there are heating and cooling systems today, they will need to work overtime without the help of insulation.

Insulation helps to keep heat in the house during the winter and heat out of the house during summer. While this may be the purpose of all insulations, there are different types that offer a variety of features and benefits. 

The most common type of insulation is fiberglass. When it comes to inexpensive options and easy installation, it is tough to beat fiberglass. But there are still some hazards when installing fiberglass, yourself.

Keep reading to find out the hazards to be aware of with fiberglass and whether it would be better to hire a professional or to DIY.

How Does It Work?

Fiberglass is a composite material made up of a plastic matrix reinforced with tiny strands of glass woven into it. Because glass reflects light and heat it has proven to be the go-to for insulation material for centuries.

Fiberglass insulation can either come as bats and rolls or blown-in. Because of this, it is ideal for all types of spaces to include walls, attics, ceilings, flooring, and crawl spaces. If it’s being blown-in it can even fit into irregularly shaped spaces as well.

One of the biggest draws to using fiberglass is the ease with which it can be installed. 

Installing Fiberglass

While fiberglass batts are the easiest and cheapest insulation to install, it doesn’t take much to poorly install it, greatly affecting its efficiency. To avoid these types of issues be sure to fill every void and split the electrical cables.

Filling All the Voids

This may seem obvious, but it doesn’t take much to accidentally leave a gap or two. When filling stud cavities be sure to push the insulation all the way back. Then gently pull the insulation forward until it is flush with the studs. This will ensure the whole cavity is filled.

When it comes to windows and doors be sure to fill the gaps around those as well. Cut out skinny strips of insulation and use a 3-in wide putty knife to stuff the insulation into the cavity. 

Splitting Electric Cables

Placing fiberglass insulation completely behind or in front of the cables leaves gaps. To mitigate these gaps the insulation will need to be split. To do this, start at the bottom begin tearing the batt in half like you were opening a book. Place one half of the batt behind the cable and the other in front. Sandwiching the cable in between.


Because this type of insulation is made with strands of glass there are some hazards to be aware when installing. This material can be irritating to skin, eyes, lungs, and even cause cancer if not handled properly.

Skin/Eye Irritation

Because the glass is so small it can easily get into your eyes. These glass particles are no bigger than dust particles. When installing or removing insulation the particles can easily break off into the air and travel into the eye. To avoid this wear protective goggles and dampen the walls before removing the insulation to lessen the particles chances going airborne.

Likewise, these particles can also get into your skin through your pores, causing irritation. These particles are also capable of scratching the skin causing rashes. Wearing work gloves, long sleeve shirts, and pants will keep this from happening.

Respiratory Irritation

Much like the skin and eyes, those tiny glass particles can also make their way into your lungs. When this happens nosebleeds, severe coughing, and lung damage can occur. When blowing insulation always wear a respirator.

Potential Cancer

All manufacturers are required by OSHA to place a cancer warning label on all fiberglass products. This is because too much of the particles in the air can become severely harmful. Wearing proper safety gear can help avoid complications from coming in too much contact with the particles. 

Professional Installation

Because of the hazards associated with fiberglass, it is best to have a professional install it. Especially if this is your first time installing insulation.

The risks for skin and eye irritation are bad enough. Add to those respiratory problems that can lead to cancer and hiring professionals seems like a great idea.