Insulation is a key factor in how energy efficient your home is. But are we insulating our homes at the cost of our health?
Many types of insulation contain questionable chemicals that can pose a health risk to you and your family even while they protect you from the elements. So we examined the different types of insulation on the market to find the healthiest insulation out there.
What we found surprised us! Keep reading to find out why, and what the safest home insulation options are.
5 Healthiest Insulation Options For Your Home
Let’s be honest- insulation doesn’t have a reputation for being the healthiest building material on the market. In the past, we have used cancer-causing asbestos and formaldehyde-based binders to help insulate our homes. Luckily, times have changed, and we don’t use these products anymore.
But what about the products that are available now? As people strive to find greener and healthier insulation options, new products are popping up all the time. We scoured the internet, examining all the products out there, and narrowed our list to the five best types of insulation for your home based on minimal health risks, ease of installation, and cost.
When it comes to healthy insulation, cork tops the list, at least according to a report done by Energy Efficiency For All. EEFA’s report focuses on insulation options for affordable multifamily homes, so they do exclude some of the more costly or experimental options out there. But all in all, when you figure in both health and cost, cork is an excellent choice.
Let’s start by talking about what cork is. Cork comes from the exterior bark of a specific type of oak tree found in the Western Mediterranean region and North Africa. Because only the outer bark is used, no damage is done to the trees during harvesting. Cork producers can harvest bark from each tree as many as 15-20 times during its lifetime of several hundred years! That makes cork a super-sustainable option for home insulation. But cork is amazing in other ways, too.
No artificial binders are needed to make cork insulation, meaning that the product is chemical-free–completely natural. To make rigid cork boards, manufacturers use leftover cork granules from the wine cork industry. The granules are steam heated and then pressed into rigid boards. During this process, the granules expand and release a natural binder. It’s like magic!
The rigid boards are available in varying thicknesses depending on what R-value you need for your region. You can expect these boards to last 50 years without the R-value degrading, so if they are more expensive upfront than synthetic insulation options, they will still pay off over time. An added bonus is that when the boards do reach the end of their life, they can be composted or recycled.
Which brings us to the original question, though: is cork insulation healthy? And the answer is an unequivocal yes. No chemicals are used, so there aren’t any concerns about off-gassing. It’s naturally antimicrobial and antifungal. It’s as healthy as insulation gets.
Fiberglass insulation is the most popular insulation on the market because it is easy to install and cost-effective. But fiberglass might not be what comes to mind when you think of healthy insulation options. So is fiberglass insulation healthy or not? Let’s find out.
Fiberglass is made by spinning molten glass, usually from recycled bottles, into small thin fibers. These fibers can cause skin irritation when you brush up against them. You might know this first hand from trying to stroke a roll of seemingly soft, pink insulation–not a good idea. But just because fiberglass is a skin irritant doesn’t mean it’s unhealthy in other ways.
Many people were concerned about the link between fiberglass and cancer, fearing that fiberglass was another asbestos. But that doesn’t seem to be the case. While there were some studies suggesting that fiberglass could cause cancer in animals, the current scientific opinion is that fiberglass is not a human carcinogen.
The other main concern about fiberglass was the use of formaldehyde as a binder. However, since 2015, fiberglass manufacturers no longer use formaldehyde in residential insulation. Now other healthier types of binders are used instead, leading to improved air quality in your home.
Overall, when installed properly, fiberglass is a healthy option for your home and your family.
Another popular insulation material is cellulose. Cellulose insulation is particularly popular as it is one of the most cost-effective insulations on the market. It is also an eco-friendly option. While different forms of cellulose insulation have been around for years, modern cellulose insulation generally refers to a product that is made from recycled newspapers.
Newspapers are shredded into small fibers that can then be packed or blown into wall cavities. However, newspaper, as you know, is flammable. So, in order to make the material more fire retardant, chemicals are added to the paper fibers.
So, is cellulose insulation still healthy? Yes. The chemicals commonly used as fire retardants are primarily borates, pretty much the same as the Borax you buy to wash clothes. There’s no evidence of toxicity. The only other area of concern is the inks on the newspaper, but nowadays, everyone is using soy-based ink. So that’s nothing to worry about either.
If you are looking for a healthy, cost-effective insulation option, cellulose is not a bad choice. It’s widely available, and it’s what we decided to go with when we renovated our First Attainable Home.
Another healthy insulation option is recycled cotton. Technically, this is another form of cellulose insulation as cellulose can be anything made from plant-based fibers. Still, we are going to handle it separately as the manufacture, cost, and installation process is different than traditional cellulose insulation.
Cotton insulation is made from the by-products of the denim industry and other recycled clothing. Rather than going to the landfill, these bits of material are being recycled into a healthy, eco-friendly insulation that is growing in popularity. The cloth is broken down into smaller fibers that are then bound into batts, just like fiberglass. You can install these cotton batts between your wall studs, easy-peasy.
While cotton is not naturally fire-resistant, the same fire-retardant chemicals used for cellulose insulation are used on the cotton batts. So you don’t have to worry about any toxic additives.
The main downside to cotton insulation is that it is not resistant to moisture or mold in the way other insulators, like cork or sheep’s wool, are. But it is a viable insulation option if you are looking to minimize your carbon footprint and be healthier.
Sheep’s wool is great natural insulation if you can afford it. The cost often deters people, but while it is more expensive than other options on the market, sheep’s wool offers many advantages.
First, sheep’s wool is eco-friendly and renewable. I mean, come on, we don’t even have to harm the sheep to harvest it. They grow a new coat every year. It doesn’t get much more sustainable than that!
But beyond that, Mother Nature imbued sheep’s wool with many insulative qualities to keep those sheep warm and healthy through the winter. And those same qualities will keep your family warm and healthy in your home.
Did you know, for example, that sheep’s wool can actually filter out dust and harmful chemicals from the air? It’s true. So unlike many types of insulation where you have to worry about potential off-gassing, sheep’s wool makes your air cleaner.
If that weren’t enough, wool can help manage moisture levels. It absorbs water and releases it to keep a relative humidity of 65 percent. Plus, it is naturally resistant to mold growth.
Sheep’s wool comes in batts, or it can be blown in, just like synthetic insulators. And the R-value is comparable to insulators like fiberglass as well. So if you are looking for a healthy insulation and can afford the cost, sheep’s wool is an amazing choice.
While foam insulation is very popular, coming in at a close second after fiberglass, most foam insulation on the market is made from petrochemicals. It also contains fire retardants that can be highly toxic. If you’re worried about toxic substances, you especially should avoid the use of spray foam insulators. Spray foam insulation contains asthma-causing chemicals and releases many VOCs during installation.
There are new products on the market that are using soy-based and castor-based oils to create more environmentally-friendly and healthier foam insulation. If you are dead set on using foam, check out one of the plant-based products.
And plant-based products aren’t the only innovations out there in healthier insulation. People are doing amazing work with hemp and hempcrete, making bricks out of mushrooms, and even making aircrete. Keep an out for more healthy insulation options in the future!
We’ve come a long way from deadly asbestos insulation. Nowadays, there are a number of healthy insulation choices, no matter what your budget is. Even previously unhealthy fiberglass insulation has had a change of heart and removed the formaldehyde. So now you can wrap your home up in a soft pink blanket and not worry about your health.
However, if you are looking for a more innovative and natural solution, look into cork or sheep’s wool. These products are naturally mold and moisture resistant. While natural insulation may cost more, it offers a chemical-free solution for your home.
You should, on the other hand, avoid most forms of foam insulation if your goal is to stick to healthy, natural substances. Unless you are using an innovative new plant-based product, chances are it’s going to be full of chemicals that can off-gas in your home and potentially endanger your family’s health.
Want to learn more about insulation? Check out our Ultimate Guide.