The Tiny house Blog

Non-Toxic Healthy Home Building - Tiny Homes - Ben Garratt

Updated on:
June 9, 2023
Ben Garratt outside of a tiny house

Ben Garratt from Tiny Healthy Homes shares the best practices to use if you want to build a non-toxic, low EMF (electromagnetic frequency) tiny house and how you can still incorporate repurposed and salvaged materials with these methods.

Ben: But yeah, I hope everyone is doing well with this lockdown. I'm pretty stoked for this event, I run an event or co run an event up here called the Small Home Expo in Vancouver, Canada where I live. And obviously, that's not going to happen this year. So, it's awesome that the guys have organized this festival online. So yeah, I'm going to talk today. I'll just go through what I'm going to chat about quickly. And these are just kind of as Paula Laport would say, in her book, prescriptions for a healthy home. And the way that I've seen it after building, whatever 50 or something homes. So, we'll talk about these things.

My background is actually my first trade as an electrician. And then I traveled over to London and worked as a carpenter, and came back to Australia where I'm from, started flipping houses, blah, blah, and then ended up marrying a Canadian to move to Canada. I was doing some house flipping here and some commercial work. And then I got really sick. And I've always had skin issues in the form of eczema. And I had this toxic shock event and my wife said not to put the photo up because it's triggering for some people. But essentially, it was a two-part paint job on one of the job sites and my face exploded into a Freddy Krueger style picture and ended up in hospital. And then after that, any small exposure to VOCs paint kind of usually pays and then my skin would crawl and my body would go try and go back into this toxic event to protect itself.

So that flipped things around for me a little bit as far as the materials I used the kind of jobs I did. So I went into natural building, and was working with some amazing natural builders up here in the Pacific Northwest. And, and then through that someone asked me if I could build a non-toxic Tiny House for them, then I built that and then you move into a space and that what happens. So that's my background. That's why I'm here. And so that first Tiny House that I built was when I started getting into like the real nuts and bolts of what a natural material or non-toxic materials of lightweight.

As I started building more, it was really apparent that a non-toxic home is different for everybody. Some of my clients are EMF sensitive, talk about that. Fibromyalgia seems to be a really common one. I work with a couple of people who have got Lyme disease. So, try to build a home that has the least amount of ingredients as possible that you've already had a chance to test on yourself, which is a hard part at the start. If you've already got some existing allergies or sensitivities before you just engage a builder to build something it is really a good idea to test the materials and be clear about what those things are that you're impacted by and then having the least number of materials is a good idea. Because then if you are reacting to something then you've only got let's say five to 10 materials that you can say that's triggering me. But a healthy home ideally is something that can keep your health at a neutral level so that when you come home you've got something that you can relax into. What else?

Yeah, and then I guess the other thing is for a healthy home for some people maybe they don't have, maybe don't have sensitivities, or allergies or anything like that. But you've got your politics you want to do eco sustainable, both of which I've got question marks on the slide because they are kind of buzzwords. I mean sustainable for some people is buying takeaway Starbucks coffee every day. For me that's not sustainable. And then a lot of the stuff that I do in my design my first point of contact for designer's permaculture and sustainability is in business might be a triple bottom line of profit, people planet profit. And permaculture’s third one is sharing the surplus and the difference between profit and sharing the surplus is worlds apart and I think where our planet needs to heal. Salvage up so called upcycle. I'll talk about that at the end.

I think just looking at the time, I'm going to have to plow through these. One of the things that I noticed almost every Tiny Home doesn't have that I incorporate is this and I'm not sure if you can see my mouse. Let's see, I used to do a quarter inch, so I had to change it. We do a half inch air gap between the metal trailer frame and the sub floor. And so, the way that I do that, and this image may not show in the most clarity, it's a little bit hard, but the ribs of the trailer I usually have at the bottom. And then that leaves space from the ribs at the bottom of the trailer to the frame, where I'll put a sub floor attached to the trailer frame. And between the wood and the metal, I use a sill gasket or a foam gasket. And then I'll have that sub flow of sticking up a half inch above the top of the frame. And then I'll install myself on the plywood subfloor. Now what that creates is an air gap, which means that we don't have thermal bridging between cold metal on the outside. And a warm subfloor on the inside that metal is going to transfer moisture. That's just what it is. And so, what I want to do is make sure that my shit does not touch the wood of my subform. Because moisture and wood equals mold, and mold is the enemy.

Little bit here on thermal bridging as well as steel studs versus wood, I see I've been attending the conference all weekend. And it's been awesome. And the steel stud versus wood thing is for sure. Steel stud is lightweight. But it does have a thermal bridge. So, if it's done right, it can work for sure. And if you really want to use spray foam, then it would have to be made into a steel stud not wood. So, the idea with steel stud is that you'd thermally break your heat transfer from the outside of your cold transfer before the start. And then you're not going to get this heat transfer.

The image here is showing a window. It's a cross section of a window. And what it's doing is showing where the glass comes up and how we've got these small points of cool air coming in at the joint, which makes sense. The other thing about thermal bridging is I try not to have any plumbing inside any exterior walls it can go through. Sometimes that again, with a hot and cold pipe running through a wall, it's going to sweat. And it also has a chance to freeze which is bad news.

I was talking a little bit earlier about the vapor barrier on the left-hand side. Here is a home that I'm building or I was building a while ago. I use Intello. There are a few other breathable vapor barriers around. I like Intello from 475 versus the plastic vapor barrier. The thing about the Intello and the plastic is the best analogy I can think of is a plastic vapor barrier would be like $1, store puncho. And then Intello vapor barrier would be like an octet six technical running jacket. So, if you go for a five-kilometer run, then you can imagine which one your body is going to sweat the most; it's going to be the plastic. And so that moisture does happen inside the wall, and sometimes on the inside of the house. And anyone who's done any renovations would recognize this picture including the indoor rain event. Let's say you've got three or four people around in your Tiny House. And Tiny Houses are particularly prone to this because they're so small breathing in and out five gallons of moisture every day.

So, the indoor rain event is when all of that moisture goes to the wall or behind the wall and it drops down a plastic vapor barrier. There's nowhere else for it to go and it accumulates behind the baseboard. And that's when we can get mold. And mold really is the enemy; for health. Generally, whether you've got sensitivities or not, you do not want mold. It never ends up with a good result.

The other one is using a humidistat. Another way to mitigate mold, especially in the bathroom. So, you've got a switch, regular light switch and a fan switch can change out your fan switch and put in what's called a humidistat control. And as soon as the humidity in your bathroom goes above 60, it will just turn on and sometimes that's going to happen, not just when you're having a shower or bath. Sometimes it will just turn on because it's the middle of winter. And that's the humidity of your Tiny House. So, trying to keep it below 60 is good.


Windows, I usually use vinyl windows. Aluminum, probably the most- well would be the most nontoxic and then aluminum in the sense that it's a stable, inert kind of product. But aluminum does sweat things. You can buy them thermally broken, which are quite nice and lightweight. But vinyl is one of my Eco compromises. It's not the cleanest product in the world. But as far as a window material goes, it really does perform well with thermal bridging install cost the whole lot. Yeah, woods very nice, too expensive. I've done quite a few with wooden windows. But this picture here in the corner is the kind of thing that I'm worried about. This is single glazed windows, that's where the swellings are coming from.

Insulation, usually I'm using mineral wall rock soil. Wall is another thing that I use in natural building or use straw bale. Minerals quite nice, in the sense, it's just extruded minerals. So they don't have to add fire retardant to it not for the rocksall. So, if you're looking at a fiberglass bat, from Home Depot or something, it will have a fire retardant in it. And the fire retardant is usually where you'll get some sort of chemical off gassing had bad making, making a break for it, which is good, was nice, very expensive gootecks wood fiber is it's a natural breathable version of what you'd use, sometimes an XPS foam or something. Again, if using steel studs, then this would be a way to thermally break the cold temperature outside to your steel studs.

Sips panels have seen a little bit of talk about these panels today as well, which is great. I don't mind them. But you would definitely have to use a ventilation system on the inside to make sure that the off gassing that's going to occur is taken care of, spray foam, XPS reflectix, people use reflectix a lot in Van conversions Schoolies. It's not technically in its insulation and anywhere where you've got non porous material touching another non porous material like the exterior of a car, or an interior wall of a car it will sweat and that moisture has to go somewhere.

Okay, here's my quick spray foam spiel. It doesn't work with wood, I'm afraid. And this is maybe the only negative part of the talk that I'm getting to. But I really feel called to kind of warn people about this. I know that a lot of people use it. Spray foam is a dead material. And it's salty by the same companies that drop bombs on other countries, chemical companies. They've got a huge lobby behind them saying that it's great. And it is for the first year. After that it becomes more and more rigid. And the wood doesn't. The wood is still expanding and contracting each season with moisture. So as the wood expands, it pushes the foam out of the way. After it's older, it cracks like you see in this picture here. Then it contracts again in summer, and now you've got micro cracks between each side of your stud around your whole house. And in those micro cracks can be moisture. They say it's a micro crack because there's not enough space to release that moisture. So, it starts breaking down the spray foam and the wood material and making way for mold to grow. Because they say it's a vapor barrier that mold and that breaking down a spray foam just comes right into your living space. If you have to use it, use the vapor barrier. So, the ovals sequester any of that kind of action away from your living space.

Okay, how’s my time?

Ventilation systems. Okay. Again, there's been such great information this week. And there was some talk about propane. I can't remember who was talking about it. Propane does create moisture. It also creates carbon monoxide. So, if you're using propane, and it's super common, I mean I use it all the time for my heating loads. If you want to be off grid, it's kind of what you have to do. Make sure you use a carbon monoxide detector. Any Tiny House below let's say will definitely use a cover monoxide Detector. Ideally, you're going to get a direct vent system. And you can see on this little slide here, that means that it's taking its combustion air from outside, not inside. So, they're definitely safer for you in the sense that it's not pulling your oxygen to burn the propane.


Now this is my favorite one and again, super happy that a lot of builders have been talking about it this weekend. But it's called a heat recovery ventilator. And the one that I use is Alunos. There are a few others out there. There's a short and a standard. And I'm just showing them how efficient they are. Now, the way that it works is it breathes out. It comes into two, two fan systems. So, there's one fan at each end of your Tiny House, ideally, one high one low, but you've got a whole bunch of stuff that you've got to get around, so it doesn't matter too much. But as far apart as they can get, so you've got cross ventilation. Now that is what it is, it's the lungs of the house. So, one fan will breathe out the warm stale air as it breathes out and heats up that core that you can see just after the fan, it's like a porcelain baffle, it heats it up. And then the fan changes direction and breathes back in the outside fresh air. It goes through the core; it heats up that outside air. And now you've got 84% efficient heat loss and airflow. Then when it takes care of the warm, stale air, it's also taking out some of the moisture. So, it's a really nice system. Really easy to install, it's about between 1000, 1500. So around two, two and a half to install. It runs on 12 volt. And yeah, amazing. Amazing.

Okay, EMF, the slide that you see, that's a WiFi router in a home and the green spot is, is where you've got the EMF radiation emitting from the Wi Fi router. In our place, we turn the WiFi off at night. We're getting bombarded across the street here anyways. But we're not getting bombarded with the green there, we're getting bombarded with more like a red, you can see it but it's not too strong. That's what a cell phone would do to an adult brain. Child's skull, the signal from a cell phone goes all the way through. So, these things aren't very well tested in humans as far as long-term effects still. So, I always use these headphones, that's an easy thing for me to do with a cell phone. And then you can buy some meters, so I'm not going to suggest any but if you've got worries about it, that's something you can do.

All of the drawings that I do, and I spend 60% of my time doing drawings or checking drawings, other builders, and doing designs for clients. Not just with a non-toxic theme, but just generally Tiny House design. This is something that I include on all of my electrical drawings, which is a note that I played off, please avoid installing electrical wires within this area. So, this is the loft of a Tiny House and that's where the bed would be. So, especially in a Tiny House and any house really tiny bit of extra AC wiring that your electrician needs to go around to avoid, especially your pillow area, let's say three feet around your pillow area, there's no reason to have any electrical outlets there. What you're going to get is this radiation field that you can see in the middle photo there in the powerlines. That's exactly how an A/C wire looks emitting.

Now I should have shown it on this one and I might have it on another but on the lower part of that on the loft deck there that you can see is where you'd have lighting for your bathroom or your kitchen or your living room, which is right at your bed as well. So, I kind of recommend using LED wiring for that. And not the kind of led wiring where you've got regular LUMIX 110-volt wire going to a lighting position, and then having a transformer and then that's dipping down to 12-volt DC. I'm sorry, from getting a little bit technical here. But what I suggest in areas again around the sleeping spaces, or an area where you're going to be a lot of the time is that you put LED lights that have the wiring of 12 volts running away to a transformer that's out of that space, because the Transformers do the same thing of emitting radiation as well. 10 minutes and then we've got these different kinds of lights. I always go for the one wire.


If I'm really getting into a nice LED light and I'm looking for a high percentage CRI a color rendering index, which is the percentage of the spectrum that you get of daylight So from morning to evening, and it's not saying that that light is going to change in real time with the spectrum, but it's going to try and pick up as much of the light spectrum that we have during the day. So, a nice CRA level is 90% or above. And I always try and get the LEDs, DC, LEDs that are dimmable because there's it's just, it's just super nice to dim lights. Okay, so material choices. This is really the best one, if you really want to get into it, then the Living Building Challenge. It's called the Red List. And that, that has a lot of information for you guys that are getting really into spreadsheets out the materials that you're going to put into your Tiny House or trying to take care of your toxicity.

The main one material choice if you're walking around Home Depot looking for glues, silicone paint is a huge one, even flooring materials. Like we're looking for, we're looking for the items that are the big ones and flooring is huge. So, if you look for something that's going to low VOC. The VOCs is kind of what the off gassing is. If you walk into a house that's just been painted, you can smell the paint and the smell that gets right up your nose and into your brain and lasts for half an hour after you've left. That's going to be the VOCs.

Okay, we made it. There are some details there for me. These are a couple of homes that I did on the left-hand side. It was the first time that I had an MGO board on the walls. It had a clay plaster after that. The whole house was built from one poplar tree, which was milled and milled up into the different us and stuff, materials that we needed TNG stuff, materials, all of that stuff was a beautiful home. And then on the right-hand side is the most recent Tiny House that we did. And Bryce did a pretty kick ass video, which was great on his YouTube channel.

But just in the last few minutes here, and maybe I'll roll through a little bit, we'll see how we go. I’m totally happy to answer any questions.

What do I think of bamboo? I love bamboo. I think it's a little heavy, but super solid. It's pretty, it's a really sustainable product, like it grows fast. There's quite a lot of glue in it. But again, there is quite good glues coming out. Now what was the- Oh, yeah, there's a plywood that they sell at Home Depot and the names just jumped out of my head. But that uses almost the most nontoxic formaldehyde free glue there is. I saw a question floating by about formaldehyde. Yeah, formaldehyde has been phased out. For sure. Well, you have to look at Home Depot for the plywood.

Let's see here. I know I'm sorry for the spray foam Dave-Dave. I mean, let's say this is my opinion. And it's anecdotal in the sense of that's what I've seen happen. There are some bigger insulation companies that do that same sort of spiel on spray foam, and they usually get sued immediately by DOW or BASF or those companies.

“Is there a cheaper way to achieve good ventilation?” Yeah, no, it is an expensive appliance. I didn't really talk about ceiling fans too much. Definitely put a ceiling fan over your cooking area. Definitely put a ceiling fan in your bathroom. I didn't get to talk a whole lot about- I mean, a ceiling fan is also great. A lot of people say well just open a window and winter in Canada that's a really nice idea, but not many people do that. If you've been spending money or time trying to heat your house if you got a wood burning stove.

“Essential Oil mold spray in glass spray bottle combined with 10 drops of oregano oil time clove oil” that's the one from old for sure, clove oil. “Good ingredients”. Yep. Thanks, Loretta. About wall insulation. We talked about wall insulation earlier just before the call started. Yeah, it is amazing, it's the most natural, let's say straws, also an installation, but you're not going to use it in a Tiny House, it's expensive. The install feels a bit funny if you're a builder and used to installing VATs wool takes about three times longer. So, there's definitely a cost to wool, both on the material cost itself, but then also the installation. I learned the hard way with that a couple of times. But if you're doing it yourself was great. If you're really doing a van conversion or something like that, a Skoolie or a, like a sprinter van or something, then wool is really a great solution there because unless you're going to spray foam it out to create a tight seal along the metal edges where it's going to sweat, then wool on that edge is less likely to mold and it can deal with the moisture. Like it's not going to change the R value too much, the insulation value when wool is wet, whereas other installations will just be destroyed forevermore. And I guess I did say that with spray foam and to put a positive spin on the spray foam, if you're doing a shipping container, or if you really want to get into it with a van conversion, then spray foam is the one anything that you've got a dead material that you're using steel studs, spray foam, shipping container, or the interior of a car wall, then spray foam is great. And then the only thing that I'd say about that would be to make sure that you've got good ventilation; just so as the spray foam goes through its natural off-gassing cycle, you're replacing that air in your house every couple of minutes with fresh air. Having air quality inside the same as outside is the key.

They reprise the videos on my website in the portfolio section. They've done a few of mine which is great.

“We've been friends for a while we met at Burning Man in New Zealand”. Thanks, Terry. Nice to meet you.

I was wondering the same Ellie, let me scroll and have a look here with the questions. “What is the best? So, what is best after wool insulation, Dave-Dave?” I use rock soil. It's the best. It's low toxicity. It's easy to use. It's stable, doesn't like slough down on the wall and it's available everywhere. And pretty cheap. Yeah, that's a good compromise that won't break the bank. But I guess alcohol stoves I don't have any experience apart from just looking at biogas digesters and stuff. Slowly making their way to market in an effective way.

“Radiant floor heat in a Tiny.” Yeah, Rebecca Well, I'm doing one at the moment, which is like an electric heat mats. I think we've got 1-5 heat mats in the design. It's a little bit of a power hog. But floor heating is the most natural way to heat a house for sure. Forced air is blowing air all over the place. It's not normal. If you go outside, we just have ambient heat, which is what radiant floor gives you. So if you can make it work awesome. Awesome. Awesome. Awesome.

Terry, “Wondering the same”. Okay, what time's almost up and I'll have a little chat after if anyone has got burning questions. But thanks so much for stopping by my house and the festival. And hopefully there was information that gave you guys some confidence to move forward. Stay safe in your houses. And yeah, please check out my feeds, my show, Instagram, Facebook. And if you need help with design, then that's what I do.

I'm not sure who was next up, let me see who was next. Oh, Lindsay, awesome. Listen to Lindsay as well.

Terry's question was asking if you consult other builders. I have done a fair bit of consulting with mint Tiny House they're just down the road here. Really A great builder. Like, just really nice people in the office, they're cranking out like one Tiny House a week. So, there's been a few Tiny Houses that I've designed that people want me to build that look exactly like a Mint Tiny House. So, in those cases, it's really if it looks like a Mint Tiny House, then they should build it. So, in those cases, I have talked to my client, I've talked to Mint and, and we find a nice medium. So I like working with other builders, because then I get to kind of do a little bit of education. There are some ideas about what I think a tiny like a healthy home is. So, Mints getting quite good at it. If it looks close to one of their models, then I'll get them to do it. A lot of the stuff that I'm doing knows a bit more custom. So yeah, I do consult and I do plans for the builders too. I have a look at their electrical plans and tweak them a little bit. And not just for Tiny Houses. I do houses around Vancouver and this and that as well. I do some natural building designs for people. Straw Bale and [inaudible].

Yeah, thanks, Ellie. Oh, man, 140 people.

“Can you talk more on water system rainwater collection, compost, etc?” Gaby Hey.


Oh, yes. Water system rainwater collection. Depending on your climate, you can get enough water off a Tiny House roof.

Usually, let's say we're here in BC you can be on the coast, Ryan, it's essentially a rainforest. What about it? If there's water coming off the roof, then I'll use a rainwater diversion, first flush diverter before it goes into the tank, so you could look that up. It's a nice little system that the first flush means that the water is coming- the rains hitting the roof. And that first flush of water off the roof goes separately to a pipe that drips away. That pipe fills up and then it continues on to the tank. And what that does is get rid of like the bird poop, the leaves the dust that stuff off the roof. So that's a nice system. Usually, I'm going to put in a bigger tank as I think I can collect water in because we do have now in this rainforest, at least a month every year where it doesn't rain at all. So, the bigger your tank, more collection you can get in the winter, the better. If you can bury the tank or coat the tank, if you're in the country, it's a very good idea. I'm from Australia, and one of the most devastating things apart from fire itself and I'm sure the same happened in California and rural areas is you see all these melted water tanks everywhere. It's exactly what you need at that time of year. So, if you can get fireproof it's good.

Compost, yes. Compost, I can talk about this stuff. Compost systems, so that 's a big thing with Tiny Houses we've got, we've got a greywater and we've got our blackwater. So usually, I'm putting in a composting toilet, usually it's separate. And so, the separate has a urine diverter that goes to gray water, the poop goes into the bucket, you got to deal with that separately. But then we've got another input there, which is the kitchen sink. If you're into permaculture you're into gardening, and you're interested in being part of the ecosystem, then a permaculture is a great system to run your kitchen water through before it goes to gray water. If you run your kitchen water as part of the gray water system and you're just dumping it into like an outlaw, drain or French drain into the ground. It's going to stink up after a while because of the fats and the food particles in that kitchen from that kitchen sink. So, if we can run it through a worm bin first, the worms will clean up all the fats, they love it. You get some compost tea as a result. And then the water going into gray water is much better to dump into the ground. I don't think I can actually suggest dumping water directly into the ground but a lot of people do it.

Terry's question was if “you consult other builders?” Yeah, got that one. I think.

“Rainwater collection composts”. Great information. thanks Wendy.

The rock sall. Yep. Terry.

“Any chance to be able to do a sauna or steam room with a bathroom with HRV or an extra one?" Oh, Lunas has another system which is a bit more robust. I think it's not the E two, but it's designed for bathrooms that the Lunas fan system, the E two isn't actually designed for bathrooms. And that's just got to do with the internal workings of it and the way that it drops moisture and this and that. Lunas does have a very efficient HRV system that might work in a sauna. You definitely need heat recovery if you want to have a proper sauna. You want to waterproof that's really carefully, for sure.

Thanks, Zack.

[inaudible] Thanks, Lisa.

Okay, I should probably clear the way for the other speakers, but please feel free to email me through my website, Instagram, Facebook, all that stuff. I'll just maybe take one more question here.

Nah. Francis is saying thanks. Thank you all.

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