Tour of my Non-Toxic Tiny House


Non-Toxic Windows and Window Coverings

Window Frames

Metal - Steel or aluminum windows with a baked on enamel finish are the greenest, safest option. It is what I used in my tiny house (pictured left). On the interior they are framed out in wood so they appear to be wood framed windows.

What is used in the windows as a thermal break is blocked by the glass and metal so there is no need to worry about any offgassing.

Wood - Wood windows are usually treated with fungicides. You could use a sealer that seals in VOCs like AFM Safecoat Safe Seal,  AFM Safecoat Transitional Primer, or B-I-N Shellac Base Primer & Sealer. You could go with custom wood windows to avoid fungicides, but they are more expensive and you still have to consider what kind of sealer you can tolerate on the inside and outside. Finding a suitable sealer for outdoor wood is tricky. AFM Safecoat Duro Stain or AFM Naturals Clear Penetrating Oil are two options. The outside would need to be re-stained on a regular basis.

Consider also the glue that is used in conventional wood windows could be irritating for the sensitive person. If you are having custom windows made see my post on safer wood glues.

Fibreglass - Fibreglass offgasses VOCs and most sensitive people do report reacting to it.

Vinyl - Vinyl offgasses VOCs and is not a healthy choice.

Gas filled - Windows filled with argon or krypton gas have a higher insulative value and both gases are considered non-toxic.

Sealing Windows

Silicone - My top choice for silicone is Eco-Bond but I review a few different options in this post.

Sealing around windows and doors - Wool products can be used instead of polyurethane foam. Some options are available at Loghome Wool.




Window Flashing

I used NovaFlash which is a zero-VOC product.

Window Coverings 

Source: Blinds Chalet
Screens - Conventional screens are very smelly at first. They can be left outside to offgas or aluminum screens can be used instead. Marvin is one brand that makes the aluminum options.

Fabrics - Fabric curtain are usually treated with wrinkle-free chemicals and flame retardants. Natural fabrics do break down in UV light but are a better option.

Blinds and Shutters - Green versions include naturally finished wood shutters, metallic venetian blinds, and bamboo roll down blinds.

Between the Glass - Between the glass is a really cool option. Here is an example.

Non-Toxic Blackout Shades - This is a hard to come by product. Blinds Chalet blackout liner is PVC- free and they claim that it is environmentally friendly. Blinds Galore has a natural blind with a cotton/polyester blackout liner. (They have a .com as well as .ca)

Avoid vinyl roller shades and vinyl miniblinds, and conventional blackout curtains.

Natural Wall Systems

The following are concrete and earth based wall systems that do not offgas toxins and are suitable for the chemically sensitive. Something a little different from the standard timber frame, spray insulation and gypsum boards:

lowcostgreenhome.com
Pumicecrete Walls

A mix of pumice and concrete are poured into forms to create these non-toxic walls. They can be made load bearing with a concrete beam. Test pumice for radioactivity and for odours that it may have picked up prior to installation.








Wikipedia.org
Hemp Crete

An interesting material making a comeback, Hemp Crete is blocks made of hemp and a lime based binder. The blocks are used to form the walls and act as insulation. They are not load bearing so are used with a timber frame.











faswall.com
Wood Insulated Concrete Forms

Forms are made of a mix of remineralised wood and concrete. Inside, rebar is used as reinforcement and then they are filled with concrete. Insulative fibers can be added or they can be filled with part concrete and part clay or a non toxic insulation. Brands include Durisol and Faswall.








aerconaac.com
Aerated Autoclaved Concrete

Concrete based blocks made from quartz, lime or cement, and aluminum powder. Test thinset mortor for sensitivity.









Is Concrete Non-Toxic?

Portland Cement should be used and it should be confirmed that it is free of admixtures such as air
entrainment and water reducing agents, accelerants and retardants, and super plasticizers. Ceramic Cement (Magnesium Cement) is also a good option according to George Swanson.


 Which Concrete Aggregates are Chemical-Free?

Natural non-toxic mineral aggregates should be used. Toxic aggregates include crushed brick, crushed 
sandstone, concrete slag, fly ash, cinder, and volcanic materials other than pumice. (Prescriptions for a Healthy House).



Wall Boards

Magnesium Oxide Board is the cleanest option. I talk more about it in my post on Bathrooms.

A FAQ is whether there are non-toxic drywalls. Of the wall boards out there DensArmor Plus is recommended by some - it is low-toxin, but not non-toxic. I do not know of any zero VOC conventional drywalls.


Natural Building: Earth Based Walls

Cob, Adobe, Light Clay-Straw, and Straw Bale and Rammed Earth

Adobe house from trails.com
These are all different types of walls made of clay, straw, and sand. But instead of giving a comprehensive overview I will comment briefly on the suitability of these building materials for the chemically sensitive. Houses made of all natural materials feel great to be in and there is no need to worry about any offgassing. However there are precautions that should be taken to avoid mould. These types of builings might be best suited to dry climates so that there is no chance of mould forming. Some people seem to be doing very well in adobe houses in the south-western US.

If straw is used in the walls it should be carefully sourced to be free of mould and pesticides. When building with cob, adobe or light clay straw there needs to be a dependable dry season of three months for the walls to dry out properly. They are particularily suited to be heated with wood stoves as that dries out the walls well in the rainy and damp seasons (source: Econest). An above grade stem wall and proper drainage around the house is also very important to keep the walls from getting damp.


Rammed Earth from sirewall.com
Another natural wall system worth mentioning in a little more detail, Rammed Earth, uses sand, gravel and clay has had an interesting development recently. Foam has been added for insulation and steel for support, and 5-10% cement is added to the clay mixture. It's called Stabilized Insulated Rammed Earth.

Water does not penetrate the walls.






Paula Baker-Laport has more tips for mould free construction of earth based walls in her book Prescriptions for a Healthy House: A Practical Guide for Architects, Builders & Homeowners

Avoiding Flame Retardants in the Home

Flame Retardants in Mattresses and Furniture

Most couches and mattresses in North America will likely have flame retardants (FRs) unless stated otherwise. Espeically those containing polyurathane foam. (Same goes for polyurathane pillows including nursing pillows).
Polybrominated diphenyl ethers (PBDE)

Dr Mercola says, "be especially careful with polyurethane foam products manufactured prior to 2005, such as upholstered furniture, mattresses and pillows, as these are most likely to contain PBDEs. If you have any of these in your home, inspect them carefully and replace ripped covers and/or any foam that appears to be breaking down. Also avoid reupholstering furniture by yourself as the reupholstering process increases your risk of exposure." (source).

A Common Question: Does IKEA use Flame Retardants?

IKEA (US) states "unfortunately we do not currently offer upholstery without flame retardants as the foam in the cushions is what is treated." They claim to use unspecified organic phosphorous/nitrogen-containing compounds, however, one blogger who sent in a sample to Duke University found that the sofa still contained the supposedly phased out chloronated tris.


chlorinated tris (TCPP)
For their mattresses they state on their Facebook Page that the  SULTAN line is "all natural", and in an email confirm that the "SULTAN HEGGEDAL is able to meet the necessary standards without the use of flame retardants." (sources: onetwo and three

As for IKEA Canada: "with foam furniture... reps say unspecified organic phosphorous/nitrogen-containing compounds or melamine or chloro-phosphorous compounds are used. " (source)
With their mattresses things are a little better, in an email from IKEA in 2014 they stated  "mattresses currently sold in IKEA stores in Canada have not been treated with flame retardants." (personal correspondence with IKEA).

Sultan Heggedal via www.ikea.com
In both Canada and the US it seems that the SULTAN HEGGEDAL (made of 85% natural latex with no polyurethane or FRs) is a fairly safe mattress. (The only chemical component is 15% synthetic latex). As for their upostered furniture, I would stay far far away.

See my post on furniture and mattresses to source natural versions that do not offgass any harmful chemicals. There are 100% natural options for mattresses that can come fairly close to the IKEA price point on the sultan line ($850).
Carpets

There are many companies making organic or natural fibre carpets, such as wool, and for rugs, cotton, rattan or jute. Carpets should explicitly state that they use all natural materials. Conventional types from big box stores contain a long list of chemicals including flame retardants.

Be careful when removing old carpets as the FRs can become scattered as dust. Do not do this yourself if you are sensitive, and have all the dust cleared before reentereing the room.

Curtains

It's hard to know which curtains contains FRs as they will not be labeled. I would assume that curtains from hardware stores and conventional stores do contain toxins unless you check with the manufacturer. I would go with an organic brand like these hemp fabric curtains



Flame Retardants in Insulation

Ridged Foam insulation 


HBCD is typically used in polystyrenes, in concentrations of up to 1% in EPS, and up to 5% in XPS. TCPP is typically used in polyisocyanurate foams (up to 10%).  (source )

There is no EPS or XPS insulation without flame retardants on the market currently. (source)

The only ridged foam insulation I know of without flame retardants is JM polyiso foam backed with foil.





Spray Foam Insulation

Almost all spray foams made in the US contain FRs according to Treehugger, usually TCPP (source)

Natural insulation options in my post on Insulation.


Retardants in Electronics

Apple phased out brominated flame retardants (BFRs) in 2008 but uses "safer" unspecified flame retading chemicals. Motorola is BFR-free and Sony has phased it out of some products (source). How much these can leach out of electronics is not clear. With furniture it is when the particles become dust bound that they become the biggest problem.


Cleaning up Flame Retardants in the Home


IQAir filter
Flame retardants become mobile in dust as opposed to gas. So keeping a dust free home is of utmost importance. David Suzuki says, "household dust is now recognized as one of the most significant sources of childhood exposure to toxic substances."

HEPA Vacuum is the best way to deal with the dust if you have conventional furniture, carpets and curtains. 

Dust also contains phthalates, metals like lead, mercury and arsenic, and pesticides (Suzuki). The best way to remove particulates and (and VOCs, and mould) from the air is a HEPA air filter. The best one of the market is the IQAir. A decent one that is a more affordable is this Honeywell.

Emergency Housing for MCS

Here are list of some housing ideas for those with environmental sensitivities needing immediate or temporary safe housing:


KOA Cabins


koa.com
KOA cabins are located across the US and Canada. The cabins are made from mostly safe materials (mostly wood) and have been reported to be good places to stay for those who are environmentally sensitive. Ask if the wood has been stained recently. The bathrooms are separate and may or may not be mould-free depending on the location.

For a list of good locations to try see this post.







Renting a Natural Home 

The Sanctuary at OUR Ecovillage is a good place to stay
Staying in a cob house (or straw bale, adobe, light straw-clay house) can be a really good option

Ecovillages may rent out rooms in natural homes and there is a possibility of getting in on the communal meal plan as well. Search for some in your area and ask about monthly stays.

The location you choose is also important as the outdoor air can be as important as the indoor air.

For a list of more locations and rental possibilities
see this post. I have seen some natural homes listed on AirBnB as well as on lists of intentional communities/ecovillages. 

Always ask about propane, natural gas, cleaning products, and water damage. 


Reflectix Dome Tent


from: www.miketyka.com/projects/desert-dome/
Regular tents are difficult because of the chemicalss used on the fabrics, the lack of insulation and the tendency for them to go musty very easily and be a lot of work with the airing out and drying out. 

Reflectix has a very high R-value and reflects light so that should work in a lot of different climates though the seams will reduce the insulative value - there are simpler designs for the structure that will reduce seams.

You can't buy these - you would have to look online for the metal structure, then buy the Reflectix, foam, aluminum tape and duct tape and then have someone make it for you. See this post for the instructions

I would also make at least one triangle out of polyethylene or an EVA Shower Liner so that you have some light. But have a flap of reflectix over it that you open and close over this "window".

For the base you could put styrofoam down and cover that with reflectix, mylar blankets or polyethylene  For something a little more permanent you could get MgO board and put it on concrete blocks. You could put styrofoam in the spaces underneath - or do MgO/styrofoam/MgO. 


Bubble Tent


source http://dornob.com
Made of thick polyethylene, these cute domes might inspire you to go glamping. They are available in the UK (Ebay) for 999 Pounds.  Hopefully they will come to North America soon.

They include a fan that circulates fresh air.
Though they would still be impractical for hot or cold weather. 





Tenting

There is no perfectly chemical-free tent as far as I know, but i have heard good things about cheap tents from Walmart, Big Agnes tents, others report LL Bean and Colmen as having been tolerable. 

For more information please see these excellent articles by EI Wellspring on Safer Camping and Safer Camping Equipment


Metal Shed in Backyard

homedepot.ca
Steel sheds can be bought from hardware stores for 700-1000 dollars. You will also need to build a foundation, pay for labour to set it up, caulk the whole structure and likely put in some insulation. For everything you need to know about setting up a shed to live in see this post by EI Wellspring.

Sheds are as not easy to take down as you would expect.








Back of a Pick-Up Truck

Try and find an aluminum canopy. The bedliner should be offgassed or can be covered with reflectix or mylar. If ordering a brand new truck you can request no liner.

Cargo Trailer

Details on making a cargo trailer safe in this post. 


Creating a Safe-Room in Your House with Tuf-Tuf 

To create a non-toxic room in your home you can use Tu-Tuf (or denny foil, or aluminum foil) on the walls/ceiling/floor. These materials block all VOCs (chemicals/toxins including mould). In terms of eyesore, Tu-Tuf is absolutely preferrable.

You want to use green Painting Tape for this as it will not damage the walls and is easy to remove - a healthy person could rip off/take down the whole room is probably 20-30 min (small room). The blue tape is toxic so I wouldn't use that. You could use aluminum tape but it is very sticky and will leave a residue/be hard to take off. 

Leave an air gap between the barrier and the wall/ceiling/floor, so it will look puffy, that will help prevent condensation. This method still may produce condensation on the other side of the barrier but with the green tape it is easy to remove a part of it and check. I would only do this in a rental or somewhere that you know you will move from in a year or less. Or just do this for a couple weeks to test how toxic your environment is. 

I have used this successfully on areas that were off gassing (a new door) with no condensation issues. 

Cover outlets, window frame but not the window. As for light fixtures I would go around them.

The only thing in the room should be clean bedding i.e. a new non toxic mattress or camping cot (etc). New non-toxic bedding and pillow. Be careful with bringing in EMFs producing devices if you use foil (that is also why Tu-Tuf is preferable). Practice decontamination and isolation - i.e. by new clothing for the bedroom and shower before entering. This will be a safe clean non-toxic place to sleep. It should help insomnia immediately. But be careful that when you open the window or the door that the air coming in might not be good, so this won't be a long-term solution. 


Other Emergency Housing

We should have emergency and long-term safe housing for people with MCS. Unfortunately this is not available in Canada. But check out the Environmental Health Association of Qu├ębec if you are a Quebecer. 

In Canada there is a national Housing Connection service connecting people renters with housing. More info here

If you are in the US, join Re|shelter's underground network

When I come across places on AirBnB that look safe I list them here

How-To: Staining Wood with Natural Pigments

Alex used natural milk paint pigments from Homestead House to stain the poplar floors and stairs in my tiny house. These pigments were extremely difficult to work with and I did not end up liking the result. But I have a few tips on how to get a better result.

The first tip is you can not go too many shades darker with these pigments. You can go one or two shades darker at most. Here you can see what happened when we stained the very light popular floor dark brown. It turned out very patchy and uneven. (Partly this was due to a soft wood and the way poplar absorbs things, but I think it would come out uneven on any type of wood).

We had to go back over the floors and sand part of it off. Then go in by hand and sand the darker bits. It still isn't where I want it to be.


The stairs went a little better as we did not attempt to go too dark there:























Applying the stain is also a difficult procedure. If you just paint it on with a paintbrush or with a cloth it will go on even more blotchy than this, and you will see all the brush lines. or lines from the cloth, because it dries in a few seconds.

Here's how to apply it:

1.  Tape off the wood along the seams in 3 or 4 inch sections length-wise. Do not tape it off width-wise or you will have a dark looking seam there.

2. Continually mix the stain/water solution so that you get a consistent amount on the brush. (2 or 3 people are needed)

3. One person paints on the stain with a brush and keeps moving down the length without stopping because it dries in a few seconds and you will have marks of where you stop if you stop. Overlapping the stain will also leave a noticeable splotch.

4. The second person follows, rubs in the stain/removes the excess with a cloth to even it out.

This has to all be done very fast.


A Note on Sealing 

On top of the stain we put hemp oil which now I know is not ideal for floors as it picks up grime from feet that can only be cleaned by sanding. The picture on the right is grime from the landing floor. This is just hemp oil with no stain.

You cannot see the grime on the dark floors, but it is there and so it feels less than perfectly clean.

A better sealer for floor and stairs is ECOs clear varnish. It's zero VOC and smells very benign to me.


Tiny House Systems for the EI

Tiny House Systems: Power, Water and Wastewater with a Focus on Reducing EMFs 

Type of Power

My tiny house is 100% electric. I could have gone with a propane on demand hot water heater and possibly with a propane powered fridge. Since these vent fully to the outside they should be safe. I decided not to because I would then have to deal with buying, transporting and hooking up propane. House insurance is also a little bit higher with propane hooked up. If you want to reduce the number of amps you are using then you will need some propane powered systems. I would not use a propane stove though as the fumes are very toxic. If you can afford solar it might be a good idea but it won't power much and then you have the added EMFs of the inverter.

Power Supply for a Tiny House

A regular house has 200 amps so what I did was take 100 amps off the house on this property with my own 100 amp panel. My tiny house is probably running on just over 60 amps so we went with 100 to be safe (we did not actually do the math on this one). Often rural properties in BC have 2 x 200 amps if they have a barn or small cottage on the land. Therefore it is not too hard to find someone that has the amps to spare. A lot of people here use wood heat and gas stoves so they can spare the electricity even on the main house.

The picture (right) is my submeter. I'm about 300 feet from the house that I hooked up to (I'm also losing some amps there from the distance but we did not measure how much) My submeter just measures how much power I am using. None of this was done through the power company nor were they informed of this. I am not on a separate bill - I just use the meter reading to know how much of the main house's electric bill I need to pay.

Between the submeter and my house the electric and internet cables are buried underground.

A mobile home park supplies either 60 or 100 amps and trailer parks provide 15 - 60 amps, depending. They would also supply fresh water and a hook up to sewage/septic.

Costs of using all Electic

In the winter when I crank the heat I was paying about $130 a month. Now it's about $50 per month (Spring).  It's better to take your electricity off a old cottage or barn that is not being used much because if you have a two-tier payment system for electricity you are paying double the rate - as you will push the usage over to the second tier every month. This is a pretty major consideration as it can cost you up to 60$ a month extra.

Tiny House Panels

Here are my panels in my utility closet. I have two panels -  one for essentials that is always on and one that can be turned off at night.  As you can see in the pic what goes off at night is the oven, lights, sockets and bathroom. What stays on is the heat/AC, hot water, fridge and mechanical room. The panel that can be turned off is controlled by a fob (a garage door opener that can be used from the comfort of my bed).

The same effect can be had from going out to the panel and turning off the unessential switches at night. But this involves going outside twice a day.

Two tips, if you have a composting toilet you are going to need that on all night (otherwise it smells) so make sure you put that on the right panel. One more tip is to have the default position as "on" for the subpanel. When my power goes off I need the fob to bring that panel back on.

There are also two sockets outside one that is connected to the permanent panel and one that can be switched off.  It's been very handy to have these two outlets in the shed for internet, heat tape (below) and for plugging in my travel trailer).

Reducing EMFs

The utility closet is separate from the house and on the opposite side from the bedroom in order to reduce EMFs. You can put foil or another EMF barrier in that wall and that will slightly shield you as well.

Having a sub panel you can switch off make more sense in a big house where you can get some distance from the kitchen, heating system etc. I don't currently turn off the non-essential subpanel at night, as it does not make a difference for me.

One thing you can try is switch off the individual breakers to your bedroom and other non essentials at night (and definitely switch off the wi-fi and put cell phone on airplane mode) and see if that helps you sleep better.

I also keep my modem out there in the utitlity room and it works perfectly fine in the humidity and in -10 C weather. This way it as far from the bedroom as possible. I keep the wi-fi off at all times. My house is wired with ethernet cables and there are three different outlets so that I can use the internet anywhere in my house. Wi-fi definitely affects my heart rate and sleep.  (Note this is not the usual way to wire internet  - you want the thick black cable to hook up to a modem outside and only have the ethernet cables running inside.)

The cable company was nice about running the cable 300 feet from the house out to my trailer where I am essentially squatting. The part where it had to be buried was up to me to do.

Water - Incoming


Here on the right is my 40 litre electric hot water tank. It's pretty small but works great for two people. It did not freeze in -10 C weather even though it is outside. If it does freeze it will crack and have to be replaced.

My water source is a hose that runs 100 ft above ground from an outdoor faucet. My hose has a heat tape on it which is that white cord coming off the pipes. Over the heat tape is insulation. This kept is from freezing in -10. The heat tape is plugged into one of the outlets in the utility shed only when it's below freezing out.



Wastewater

Here on the left is a not so great picture of where my greywater goes. (I have no blackwater because I have a composting toilet.) All the water from the shower and two sinks goes into a pit that is just outside my house. It is so overgrown with plants that it is very well disguised and impossible to take a picture of. In the winter though you can see it and if you are trying to avoid inspectors seeing it you will need to come up with another way to hide it in winter.

The red rectage shows how big it is. It is not very big at all, about 1 ft x 4 ft. I keep thinking it needs to be bigger but it has not caused me any problems as it is. I have had to go out and remove the sludge that builds up a couple times in the last 8 months. I don't have any filter on it that prevents oils/grease/food particles/hair conditioner from going straight into the pit.


Heating and Cooling

Lastly, my heating system is tucked in in the top part of my utility closet and is hard to take a picture of. It is a mini-split heat pump which provides heating and cooling. It has a dehumidifying mode but it does not pull moisture from the air - it is simply an adjusted AC setting. I also have two extractor fans, one above the stove and one above the shower to remove excess moisture from the air and that works well to keep my humidity levels in the safe zone.

The heat pump is 12,000 BTUs which is more than the company recommended but I am glad I went with it anyway. In the winter I often had it on full blast with 2 space heaters going as well and on the hottest days (up to about 30 degrees C) the AC is needed on full force especially with cooking and showering all in this small space.

Sneak Peak and Q&A

I made a short video-tour of my tiny house and will follow with some Q&As below!


 


What are the dimensions

The whole trailer is 20 x 8, the washroom is 30 inches x 8 feet and the kitchen is 7 feet long. Therefore the living room is around 10 x 8 feet.

What kind of wood is that and what are the walls made of

Poplar is the wood used throughout. The walls are MgO board with clay plaster.

What would you have done differently

I would not have used poplar - I would have used maple because it's a hard wood that is low odour (low terpenes). I would have used cedar for the framing because it's so rot resistant.

I would have used lime plaster and not clay throughout (and not used wheat paste under it as it is susceptible to mould).

A vapour barrier was not installed on the warm side and this was a major oversight. The insulation will need to be redone next summer. I would not have used cotton as well since it's to mould prone and smells like sizing chemicals.

I also would have planned the washroom dimensions around ready-made shower enclosures and the size/requirements of the composting toilet. Installing a custom shower and composting toilet after the fact raised the costs - this should have been planned for and installed during the build. I would have left out the grey and black water tanks as they are not necessary. And again not have used cotton insulation in the bathroom walls especially without a vapour barrier.

The bathroom also has no heat source and gets extremely cold without a space heater.

The heatpump, despite it's robust size is not adequate for the winters - I have three space heaters at the coldest time - and for me is barely adequate as AC in the summer. The condensation tube is also too small and plugs up easily.

What aspects are you happy about

I'm really happy with the design and layout - it definitely serves my needs. I am exceedingly happy with the window alongside the bed. Since I am disabled I spend a lot of time lying in bed but now I can watch the birds and look at the trees and mountains.

What do you do for laundry

That's something I would have done differently -put in a combo mini washer/dryer under the stairs instead of storage (I do it all by hand now).

Where is the rest of your stuff

I have a few things in plastic bins under my house and in my car. There is room for more storage in the house: there is space for shelving above the toilet, a deep closet at the back of the landing as well as hooks behind the front door. In the corner where I have my laundry hanging there could be a bookshelf instead. There could also be sleving on the back wall of the kitchen. I chose not to put in these additional storage spaces because I do not need them.

Building a Non-Toxic Tiny House: Some Considerations

Some preliminary considerations if building a tiny home with all natural materials:

1. Choosing Plans

my house
There are not a lot of companies selling technical drawings for non-toxic tiny homes. I only know of one: Tiny Green Cabins. Because I wanted a more modern style, I bought conventional plans from Leaf House. I wanted to change the layout to make the living room bigger, which entailed changing almost every other aspect of the design. In a tiny house, one change in the floor plans can change everything. This ends up costing a lot more not just in time spent redrawing plans, but in recalculating all the supplies: lumber, the electrical system, the plumbing system, (custom) window sizes etc. A lot of time (months) was spent calculating and ordering supplies. A week was probably spent on window placement and sizes alone. In order to reduce costs you might want to start with pre-fab window sizes (or salvaged windows) and design around that. But it's way more efficient cost-wise to buy plans that are almost exactly how you want things to look.

the floor plan for my house
Just the change over to non-toxic materials  demands the following: changes to the framing in the flooring, changes to the thickness of the walls, ceiling, and floors (since insulation will be thicker), and changes to the weight. Not to mention non-toxic material are generally twice the cost of conventional! You will also need to recalculate quantities of materials if using conventional plans, as you change from plywood to MgO board, and from foam (or SIPs), to cotton or wool insulation.

Here is my builder's photo blog where you find a lot of tips on chemical-free modifications such as sequestering pipes, building a floor without plywood etc.

2. A Builder who Understands Chemical Sensitivities

I can't even imagine building with someone who did not have experience with natural building as well as a complete buy in to the idea. The amount of time it would take a conventional builder to learn about non-toxic building would not make this a financally wise decision. It would also add a lot more work to your side and a lot more stress. Some tiny house builders I recommend are Ben Garrett, who built my house (BC, Canada), Jim from Tiny Green Cabins (MN, USA), Swanson Associates (TX, USA), Safeshelters (CA, USA).

3. Trailer Weight

the beginning of my house
A big SNAFU was that the plans we bought were designed for a trailer rated at 10,000 lbs, but when you switch from conventional to natural materials you add a lot of weight. MgO board is much heavier that drywall and plywood; MgO siding or HardiePlank is heavier than wood siding; cotton and wool are heavier than foam insulation; and tiles or hardwood are heavier than vinyl or laminate flooring. A composting toilet is also fairly heavy. Because of this we were not able to put the other side of the walls on.


4. Metal v. Wood

my poplar frame, should have used
cedar or maple
Metal versus wood framing is a really important consideration. To oversimplify the issue, metal framing involves using a thermal break of either foam or bubble wrap. It gets a bit more complicated than that, but this discussion by Tiny Green Cabins should help. Another possibility to to build the walls out of metal. For someone that cannot tolerate wood or MgO board this is an interesting new option. Check out this Facebook page and upcoming book to learn more about that. Consider that having metal walls, including foil inside your walls can aggravate EMF issues.

If you can afford it consider Timbersil for the framing, it is an excellent material that solves the usual problems of wood and metal.


5. Mobile Home v. Travel Trailer Registration

MgO walls going in
This was one of the most confusing aspects of the build. Regulations vary from Province to Province and I'm assuming from State to State as well. In BC to get your house registered as a mobile home you have to have it built by a certified mobile home builder. Now, how exactly you get certified is not something you can easily find out, and multiple calls to government offices only resulted in completely different accounts, most of it wrong information. I am assuming that it is only large companies that can afford this paperwork and fees which means you are not going to be able to build a non-toxic mobile home in BC which is ridiculous. If you can find the work around here please let me know, and this is something we all need to work to change. Not getting mobile home certification means not being able to park and live at a mobile home park which is unfortunate. I will write a full post on where you can park a tiny home in BC.

You can easily get certified as a travel trailer in BC (Ubuilt Travel Trailer is the specific designation) and this will also cause a lot of confusion at ICBC). You must find out the requirement before building, though there are not many requirements, i.e. one is the height, and another is a light on the back. There is an inspection sheet that is filled out at a mechanic that is certified to do this. Then you take that sheet to ICBC and hope that someone there figures it out (took me 5 trips to ICBC in total). You can then get house insurance as a mobile home or as a travel trailer.

The requirements for a mobile home are much more thorough (if you are a mobile home certified builder) and must be contemplated before building. For example, with travel trailer certification, there was no requirement about grey water and black water tanks (and it turned out we did not need those tanks at all). No rules about composting toilets, nor was there any kind of meaningful inspection of the electrical system. Please make sure you do get the checklist for travel trailer before you build. It does have to be able to be moved so there are requirements for having it on the road.

If you are having someone in the US build it get them the checklist for your province though it will likely be the same as the requirements in the US. You can import a travel trailer which is a bit of paperwork and might involve you going down to the border to do the paperwork.

6. Choosing Materials

Poplar wood on the interior too (should have used maple)
It's hard to overestimate the time it takes - not just to re-draw plans to accommodate chemical-free materials - but to source and order those materials. I think we spent two months sourcing just the basic materials. You will have to do the leg work here as it's not possible to generalize where to procure non-toxic materials in every area. (Here is the sourcing for many of my materials). Every area will have a different supplier for MgO board, lumber, natural insulation, and the list goes on.

Factor in another couple of months to order samples and test materials for your own sensitivities. If you get sick easily, this will be a long and protracted stage as you find out what you can't tolerate by getting sick over and over. There needs to be time for recovery between testing. Definitely err on the side of caution as your sensitivities will increase once in a clean environment. It was a happy mistake that the finishing was left to me after delivery. the testing of wood stains/sealers/paints/tiles/tile sealers/shower materials has been a very long process and it has been much easier to do this slowly over time. Materials that I didn't react to when testing but now do include: cotton batt insulation (if you react to new clothing you will react to that), MgO board (I am on the fence about it - a couple extremely sensitive people have said there is a slight reaction to it) and I have become much more sensitive to all paints and wood glues.

7. Time to Offgass
the view from my kitchen

Many materials and appliances will need to offgas before use. I didn't do that well in my house for the first couple months so I would say even with the best materials there is wiring, there is plumbing and plumbing glue, there is wood glue, there will be some silicone in the walls - these all need some time to offgas. We left the appliances running for a month before use.






Separate posts on: low EMF electrical system, materials list, where to park your tiny home, composting toilet and grey water, custom non-toxic shower...

More pics of my house here.

A Non-Toxic Shower (Mobile & Non-Mobile Homes)

It took four people, five months to design, make and install a totally toxin-free shower, that will:

-never get mouldy
-last a lifetime
-and hold up in a tiny mobile home (that flexes when it moves)!

But we did it! We were this close to giving up and building an outdoor shower. In the end the shower enclosure was made of aluminum and stainless steel with a zero VOC adhesive.

The details are below, but first, some plans that didn't work (but may work in a non mobile home).





What didn't work for me:

Tiles

My first plan was tiles, but grout without additives (plain Portland Cement) will not hold up in the long-run to mould or to cracks in a mobile house. Even with Kurdi barrier underneath, I still felt like the area around the drain would be susceptible to cracks when the house moved. And I could not find a zero-VOC grout sealer to waterproof it.

Tadelakt

A non-toxic waterproof finish, tadelakt was also considered. However, all the plaster in my house has cracked. Some ideas to give it a little flex include - adding glue to the plaster and maybe a mesh underneath on the wall, but no one has tried this yet in a mobile home so it was a fairly big risk.  In a regular house (not on a trailer) this would be my first choice. (For the base/floor you still need tiles, fibreglass or metal).

Fibreglass

Will last a lifetime without getitng mouldy but companies need to use their own adhesive, which is hugely toxic. Fibreglass offgasses styrene and most highly sensitive people say they react to it. If you found a used one or let one offgas and then installed it yourself with your own non-toxic adhesive this could work.

Other Options 

In a regular house, polished concrete might work really well, if you can find someone who can do that finish on walls and tight spaces. Glass walls are something to consider. An outdoor shower could be made of cedar, glass or concrete. More discussion on these materials in my post on bathrooms

My Chemical-Free, Mould-Free Shower! 

A basin with 2 inch sides is made of stainless steel and the pipe in the center is welded in so will never leak around the drain (Stainless is going to hold up better than alum in the basin).

I would have done more of a grade and a higher lip on the basin if I did it again. Underneath we used pieces of arylic and Butyl Sealant Tape to support the grade.

There are two sheets of thin aluminum panels that wrap around the three wall shower enclosure. The first piece of aluminum wraps around the three walls (no seams in the corners) and overlaps with the basin at the bottom (will never leak at that point).

The second piece of aluminum overlaps over the first piece and goes up to the ceiling. A vent is right in the middle of the shower on the ceiling to reduce moisture. I am wondering if I should have had a piece of aluminum made for the ceiling as well.


The shower curtain is this EVA non-toxic one (had a slight plastic smell but was fine for me) (other curtain options to try are polyester or polyethylene - or, even better make a glass door). My curtain has magnetic pieces that stick to the walls - to prevent water from splashing out onto the tiles which are not 100% waterproof (magnetic strips from Bed Bath.......and Beyond!)

After testing many adhesives with no luck I finally found Almighty Adhesive by AFM and had no reaction at all to it even when wet! The problem of finding an adhesive was holding up the project for months and I was so excited to finally find this. It is also the only adhesive (including silicones) I have ever smelled that really is non toxic. Even a regular non-toxic white glue smells more than this stuff.





Around the edge of the aluminum will be sealed with AFM silicone which does take about a week to offgas. That is the only part with any toxins. I don't think it is entirely necessary......but I really want all the edges to be sealed. Strangely (happily) I no longer find this caulking to be problematic.



So there you have it! A shower that will never leak or become mouldy and with no toxins! 
TA DA

my bathroom
I have to thank the guys at BathMaster because they spent weeks problem solving this, designing the shower, and getting it custom made. They were willing to do whatever needed to be done to get me a shower I could tolerate.

Notes:

Once thing I would have done differently is not use any batting insulation in the bathroom walls. If moisture gets into the walls then it's over in terms of mould. I would have used only hard foam.

Another thing to consider is to weld all the parts together. See Tiny Green Cabins stainless steel showers if you are interested in that route.

The custom aluminum and stainless cost 800 CAD + installation which took 2 people all day. (We had to re-do some plumbing though which took longer than expected)