As a company trying to improve the health of our built environment, we field many questions about non-toxic insulation and how to build a non-toxic home or reduce the toxicity of an existing one. Luckily we have a good friend Corinne Segura of My Chemical-Free House who is an expert on chemical sensitivity and how to create healthy homes.
What follows below is a conversation with Corinne to understand her journey and her impartial, objective approach to a non-toxic, chemical-free home.
Thanks so much for joining us, Corinne. Please tell us a bit about yourself and how you became interested in healthy, chemical-free building.
Hi Philip, Thanks so much for having me.
My journey started out with me having extreme multiple chemical sensitivities (MCS) as well as extreme mold sensitivity. I started out choosing materials for a chemical-free tiny house since that was my best option for healthy housing at the time. After that, I became very interested in researching and testing healthy building materials since there wasn’t enough guidance or information out there when I was building. From there I became certified as a Building Biologist and have started the blog My Chemical-Free House.
Ok so what are the most dangerous chemicals out there and what materials are they in?
I would say the number one building material to avoid is two-part polyurethane spray foam. This is usually used in attics or roofs but sometimes it’s used in the crawl space and sometimes it’s used throughout the whole house, in all of the walls. This is one product, where in my experience, there’s a big discrepancy between what the company’s numbers are, in terms of the VOCs that off-gas from it, and what it’s really like in the field – in real life. In my experience, it’s far too high in VOCs for the first few years at least. And sometimes it goes terribly wrong which is a really big disaster.
In terms of materials on the inside of the house the next two highest off-gassing materials are vinyl sheet flooring, and rubber flooring which is usually used in gyms.
There are a few other smaller materials like glues that I would like to avoid if it’s possible.
I have a blog post that is on the highest priority chemicals to avoid if anyone wants to go further into this topic. See HERE
Tell us about the impact of toxic chemicals from everyday materials in our lives.
Well, there are certainly lots of studies on the health impacts of specific chemicals, for example, formaldehyde and phthalates are two that are quite well known. But there are many other chemicals where we don’t have a very clear scientific consensus yet on the health effects, and yet we’ve gone ahead and added them to products anyway.
If possible we would avoid all added VOCs as well as all harmful persistent chemicals that are semi-VOCs. The semi VOCs are not usually in gas form and those include flame retardants, many antimicrobials, and plasticizers.
Then of course there are non-volatile chemicals like toxic metals and heavy metals.
For the non-volatile and semi-volatile chemicals we usually just have to go based on what we know about them since they usually don’t have an odor or much of an odor, and those of us who are extremely sensitive may not have a short-term reaction.
Transparency from the companies is extremely important so we can start to make our own decisions on what chemicals we want and don’t want to bring into the house. For those of us with chemical sensitivities, we usually can gauge the health impact of VOCs based on our own reactivity but it’s really important to hone this ability.
In order to become our own best guide to what is good for our bodies, we have to start with a really clean slate, a clean environment in our home, so that our bodies can show us when something new comes into the environment that isn’t good for us.
I do think those with multiple chemical sensitivities are actually a really good canary in the coal mine into what chemicals may be harmful and how harmful they are.
It’s often difficult to just look at chemicals on paper and get a sense of just how high of a priority they are to avoid. Some of the certifications out there are in theory there to help us decide which chemicals have a negative impact on our health but they are very imperfect.
Some of them can even be very misleading like when you see a Prop 65 warning for cancer for something that would have to be in dust form and inhaled into your lungs to be harmful when in reality the product would never be in dust form.
What are some of the common misconceptions you hear from folks about building a chemical-free house?
To start from the beginning, I would say that a lot of people are rushing the research and testing materials stage.
Before you engage with the builder and certainly before you actually start building you definitely want to have your main materials list sorted out. Depending on each person this could be fairly easy or this could be a very detailed process.
Getting samples of the materials to see them yourself is very very important for sensitive folks. Going into it blind is almost never a good idea.
I help people one-on-one to make their materials list so that we can go through the top choices available based on data from those who are sensitive, look at the pros and cons of those materials, and sift through the information much more quickly.
The second thing that most people underestimate is how much building science really needs to go into building a mold preventative building, even if it’s a tiny house.
The only way I can try and back up that assertion in a short sentence is to say that for those who are severely mold sensitive you know how difficult it is to find an existing house or trailer that is free of mold, and so to build something different you’re going to have to go above and beyond what is the norm.
What about cost? Often healthy building materials have a higher “upfront” cost than conventional materials. How do you address this issue with your community?
For most people that I work with, health is the top priority.
There are a lot of materials where we don’t need to spend more money on them, there are even a couple where we could go for something cheaper than the norm.
There are only a few materials that are going to cost more.
Wool insulation is one that does cost more than some of the standard options, but for those who want to go all-natural, there isn’t really a comparable non-toxic insulation option. So when that’s the top priority it’s not usually a difficult decision for folks.
There are also some who have tested the other insulation types and have not found them to be good enough for them and so their health really guides them towards wool.
Your overall budget for healthy materials is very likely going to come in at a higher price point than your average American home but there are some ways that we can cut costs in other areas.
The obvious one is to make the house smaller but there are less obvious ways to make the house simpler in terms of construction.
It’s really important to know what your priorities are and keep them front of mind. I sometimes do meet with clients who are set on having a three-bedroom house when they have a one-bedroom budget and they do not want to compromise on that. So that’s where it becomes really important to make sure that when you do have an environmental illness you’re putting the health impacts first otherwise what good is a three-bedroom house when you’re still feeling sick from off-gassing and/or mold?
How can people find out about the chemical composition of materials and /or test them?
In an ideal world, all of the companies would tell us what all the ingredients are. We are making some progress in this field.
With your company, one thing that people like is that they know everything that is in it.
There are also a few companies now that use the Declare label, like you, which discloses all or almost all of the components and ingredients.
Most materials don’t provide this though nor do they provide a detailed line-by-line VOC test result.
I would say that most of the certifications are useless or almost useless especially for those who are extremely sensitive.
So my method of finding out what’s in materials has to do with putting together multiple sources in order to come up with the common ingredient list in a product.
For example, if I’m looking at caulk and somebody sends me the SDS. The SDS likely only shows the filler ingredient and a couple of the much smaller additives. It usually does not show me the main polymer or the main solvents.
In order to have an idea of what all the ingredients are I look for those few companies that actually outline all of them. I look through patents for materials, I read industry documents and books from that industry on how materials are made, and I often sniff test them side by side to compare it against one that has a declared ingredient. Like a dog trained to sniff out different chemicals, I can compare them that way and usually figure out what the main chemicals are.
So that’s the background information that I’m using and that way I can use an SDS sheet that only has a couple of axillary components listed and then figure out what category of caulking it falls into and what additives that one likely has.
How important is non-toxic insulation for a healthy home?
Choosing the insulation is one of the first items that we will go through when working together on a healthy materials list.
It’s one of the main materials and it’s obviously quite foundational to the structure so we need to make sure that the builder has the information early on. The same would go for a renovation of course.
It’s also really important to factor this in even in the design stages of both a new build and a renovation.
For example to avoid spray foam inside a roof or ceiling we often need to change the design of the roof or approach it totally differently.
Even in the walls, the type of insulation can affect the moisture management system. If it’s a renovation of an old building we need to know what was in the walls before so that we don’t fundamentally change the moisture management system that was working.
You also need to think about whether you want or need insulation between interior rooms. For example, the bathroom and bedrooms often have insulation in those walls.
Your website has a lot about mold and its effects. Why is mold so harmful?
Mold is the underlying toxin injury behind multiple chemical sensitivities. Without getting to this source problem we’re not going to be able to help someone get out of the loop of extreme chemical sensitivity and avoiding minute amounts of even everyday toxins.
It’s a cycle that needs to be broken. For those that are the most extremely sensitive they often skip on building materials that are essential to the moisture management system, meaning they have compromised the structure in terms of moisture and eventually mold. That will guarantee that they are going to go in circles and not break the cycle of multiple chemical sensitivity and get better.
Once folks try out this hypothesis it will become obvious quite quickly as long as they were successful in getting out of mold.
Chemical sensitivity is not a lifelong sentence. Most people recover when they get the mold component in place and try some detox for the body.
Are there any new products that you are particularly excited about?
I’m excited about having more options to replace vinyl flooring. Both sheet vinyl, which is high in VOCs, and luxury vinyl plank which is not high in VOCs but contains plasticizers that are not likely to prove healthy in the end.
There is a biopolyurethane sheet flooring that can replace vinyl sheet flooring and is far healthier. In terms of click-together flooring that is waterproof, there are some polypropylene options that are improving.
There are also some woods that are treated and ways that are not toxic and this can be useful for wood that holds up better as siding, decking, and for windows. Accoya is the best-known brand but there are quite a few options now.
I also like the new plaster-paint products that can look like plaster but go on more like a paint. There are some that are lime wash and there are some that are thicker troweled on paint. They are very low in synthetic additives and very low in VOCs and they look cool too.
What are the best ways for people to find out if they are chemically sensitive?
You don’t have to wait for a doctor’s diagnosis. I have a lot of people who contact me for a consultation and they say – I don’t have chemical sensitivities but I feel sick around air fresheners, smoke, etc.
That is chemical sensitivity. You don’t have to have a diagnosis, it’s all about listening to your own body. If you do find that you have those sensitivities to fragrance or any harsh chemicals then you’ll want to start to see where you fall on the spectrum by testing out some less potent chemicals.
Taking a camping trip to a pristine area is always a good idea to help your body form a baseline.
Clearing your house of chemical cleaners and synthetic air fresheners is also a good idea even if it’s just for a while to again establish your baseline. The more your baseline environment is a clean environment the more your body can clearly tell you which compounds are bothersome. If you try that for a while you might find that then, when you try febreeze or other more typical chemicals, that they don’t feel good for you.
That doesn’t mean you need to avoid everything that could be potentially harmful, but you can
decide where you want to go from there.
Corinne, thanks so much for your time. This was a great conversation and once again, we’ve learned a lot!
Terry Meredith
We have Havelock wool insulation in half of our house. We did a renovation and took it down to the studs. How can I put it in the rest of the house without removing allthe sheetrock?
Philip Walsh
Ah, that’s a tough one. The industry calls it a “drill and fill” and it can be hard to understand its effectiveness as a consumer as you can’t see the job performed. Overall we do not recommend it.
If a DIY we’d buy a $40 digital endoscope on amazon, be prepared to drill 2 holes (to later be patched) in each stud bay and be prepared for some trial and error. It can be done but lots of variables exist. If old wiring then we’d tear the walls down and rebuild. The joys of a remodel
LNC
We are doing a major renovation, but keeping our plaster walls intact as much as possible. The plan from our architect is to drill and fill, as already mentioned. Then, check for problem areas with a thermal imaging camera, and then add more insulation in any spots that did not get filled.
Kim Goodwin
Corinne’s comment “a lot of people are rushing the research and testing materials stage” is the biggest issue I also run into with consultations, as well. People really do want to rush this part, and seem to think that if something has a “safe” label, it will be fine for them. Taking the time to order samples of materials and see how one does with them, is often overlooked as unnecessary. My husband and I are currently building our own home, and I started sourcing materials, getting samples, and making sure they didn’t bother me three years ago. That seems like an excessive amount of planning to many people, but it reduces surprises. For instance, I ordered wool insulation samples from three companies, and only found Havelock’s agreeable to me. I couldn’t have guessed that ahead of time. Thanks for the wonderful interview. Very informative.