Expert advice from Bob Vila, the most trusted name in home improvement, home remodeling, home repair, and DIY.

roofing, hvac

Back to Basics: Types of Insulation in Your Attic

By Remodel It! Columbus Ohio's Best Home Remodeling Contractor on Dec 04, 2013

Being warm blooded, we always have to regulate the temperatures around us to feel comfortable. Whether you live in hot clammy states or cooler, snowy states, the fact of the matter is, we all use in-home heating and/or cooling. But without a good R-value insulation (R-value refers to the capacity of an insulating material to resist heat flow, so the higher the R-value, the greater the insulating power), your hard earned money is practically leaking out of your home in the form of hot air in the winter or your house gets “baked” in the summer increasing your cooling costs. There are so many ways to insulate your home, but up to 85% of heat loss in the winter could be through your roof as warm air rises, so seal up that attic.

There are so many different types of insulations you can choose from. Each has its own pros and cons. The 5 most common Insulation materials are:

1. Mineral wool

It is made up of volcanic rock and recycled slag melted at extremely high temperatures and then the fibers are spun together. It works great as a permanent insulation that does not need to be replaced, does not absorb water and is an excellent fire retardant. The installation of Mineral wool is definitely a job for an experienced installer though as proper gear and precautions need to be used during installation. If you do not, you’ll be in for a lot of itchiness and discomfort that’s hard to shake plus eye, skin and respiratory irritations. The R-value per inch is 3, so even though it does not need replacing, you would need around 10-15 inches to reach your area’s R-value (depending on where you live, of course)

2. Cellulose

This is the green option as it is made up of around 75% post-consumer recycled newspapers, it’s efficient, non-toxic and affordable. Cellulose is also an excellent air-blocker, which is great if you have any cracks or little holes where warm air can escape from. The R-value is between 3.5 – 4.0 per inch thickness, depending on if it is loose fill or dense packed material. Specialized equipment and experienced contractors are required for this installation.

3. Fiberglass

Probably the most well-known insulation material. It is made up of glass that has been spun into fibers then woven and coated with a binding agent. It has to be installed perfectly to retain its rather lower R-value compared to other insulations. But even with a perfect insulation, if there are any gaps whatsoever or if it gets wet or is too tight or too loosely packed it can lose up to 50% of its R-value. It needs to be installed in a place that has no air leaks at all and where no moisture can reach it. R-value between 2.5 and 3.8 per inch of thickness depending on loose fill, blanket/batt or high performance fiberglass insulation.

4. Polyisocyanurate

Polyisocyanurate is a closed-cell, rigid foam board insulation. Because it has such a high thermal performance in the home building market, it is the product of choice for energy-aware homebuilders and consumers. You can easily identify it as it has one or both sides of the insulation wrapped in foil. It has the highest R-value ranging between 5.8 and 7 per inch of thickness yet still remaining cost effective and eco-friendly.

5. Other Foil insulation

Also known as reflective insulation. It is basically an insulation that uses a foil finish to deflect hot air from coming in (summer months) or going out (winter months) through your roof. There are many types and brands, each offering something slightly different from the big box store to higher quality ones only sold and installed by dealers. The questions you should ask with reflective insulation is the R-value and permeability (can it “breathe?”). Permeability is important so moisture does not get trapped to create mold. One of the most popular reflective insulators at present is eShield which also has high density encapsulated fiberglass that produces a system R-value of 11.6 with 2 layers of reinforced reflective insulation. It is said that it reflects 97% of heat that comes into contact with it. This way, hot air isn’t trapped in your attic, but reflected back out in the summer and warm air from the house is reflected back down into the house in the winter. The trick with this kind of insulation is, it needs an air pocket or other insulation in the attic to work optimally. EShield also has a permeability rating of 13. Reflective insulation is a great add to your existing insulation to improve your R-value. Refer to your area as to what R-value is recommended for optimal energy efficiency.

With the winter coming up, I hope this list will aid in your decision as to what kind of insulation you’ll be getting to keep your family warm this winter. Please feel free to comment

Visit Remodel It! Columbus Ohio's Best Home Remodeling Contractor »

blog comments powered by Disqus