WHAT ABOUT HEMP CANVAS?
In 2004 I made my first Hemp Tipi, in response to my growing awareness of the toxicity of the treated cotton canvas which I had been using exclusively since I began making Tipis in 1997. I had become especially concerned about the flame-resistant chemicals in this canvas.
I discovered in my research that the whole cotton industry is one of THE most toxic industries on the planet! (In the top 5). The cultivation of cotton requires enormous quantities of toxic chemicals, in the form of pesticides, herbicides, fungicides and fertilizers. This cotton is sourced from India, so in order for me to provide a cotton canvas Tipi to you, the soil, air, water and people in India are being polluted. Not only that, the finished canvas is then imported to Georgia, where it goes to the “finishing plant” to be “treated” with another array of toxic chemicals to provide a canvas that is resistant to water, mildew and fire. Again, the soil, air, water and people are being exposed to this pollution. And then in order to turn the canvas into a Tipi, I am also exposed to these chemicals while I work. And then the question arises......how does this affect the folks who use the Tipi? These facts and questions were the main motivators in my seeking a more Environmentally-friendly canvas. In researching Hemp fiber, I discovered its remarkable qualities and felt it was a promising alternative. I now have 10+ years experience using this fabric for Tipis, and the results are mixed.
Foremost, I absolutely LOVE working with Hemp! It is beautiful, easy to handle and makes a superior Tipi. The quality of light that you experience inside a Hemp Tipi is so ALIVE compared to the treated cotton. However, it is not suitable for certain climate conditions, unless treated and painted.
Hemp is highly absorbent but mildew resistant. What happens when the Hemp Tipi gets rained on? The fibers immediately swell up, making the canvas tight so that it sheds the rain. It does feel damp to the touch, but the rain does not leak through. This is great! But it can be troublesome if you have bedding, clothing or books touching up against the Tipi wall or liner, because the moisture will “wick”, or transfer to your stuff. It's not so much of a concern if you are in a dry climate and rain comes infrequently. The Hemp dries out quickly when the source of moisture goes away, & it's easy to keep your things a few inches away from contact with the canvas. However, in a high-humidity environment the Hemp doesn't have much chance to completely dry out, and although it is known to be “naturally mildew-resistant”, if it is under constant exposure to moisture it will begin to mildew, especially where it is in contact with the poles.
This dilemma led me to search for a non-toxic way to treat the Hemp canvas to repel water. I found “CottonProof®”, sold by a company called NikWax. It is a liquid concentrate that you dilute with warm water and apply to the dry canvas, best applied with a long-handled paint roller. This is done outdoors during warm, dry weather, with the Tipi cover/liner/door spread out flat on large tarps. An 18-foot cover takes 2 people about 2 hours to treat. The canvas is then left to air-dry for a day and it is done. I recommend following with a thinned (50/50 with water) coat of exterior latex paint, within one year. Otherwise, you need to re-apply the treatment again in 4 years.
The other major influence on the viability of Hemp as a Tipi fabric is the effect of UltraViolet rays. Indeed, I consider this to be the main impact on the life expectancy of a Tipi, whatever fabric is used. So, unless your Lodge is made from PVC-coated polyfiber, (which I don't offer), it is going to be impacted by the sun. In fact, I have heard a significant increase in feedback about UV deterioration in the past year, coming from customers who purchased Tipis in 2010/2011. This was not limited to those who purchased Hemp. Is our atmosphere changing? Has the fabric quality diminished? I can't make any declarations here, but something's up. The “normal life expectancy” of a Tipi has been lessened for some reason. Case in point: My personal Tipi was made in early 2002, which means 13 “seasons” of use, to date (2/15). Two years ago it began to show signs of UV damage. This Lodge has gotten very heavy use, put up and taken down multiple times per season and left up all thru the winter months two times. Aside from a repair due to a young deer who ventured inside and then kicked its way out, the canvas has held up remarkably well. This was made from 10-ounce Sunforger, a lighter weight than I use nowadays. Tipis made from this weight of canvas can now be expected to last only 5 to 7 years. I now use only 12.65-ounce Sunforger Marine. ( & Only non-fire-resistant, after finding out that the FR chemicals increase the rate of UV damage).
All these factors can be addressed with one solution. To prolong the life of the canvas, whether Hemp or Sunforger, give it a coat of very thinned exterior latex paint. This is the best protection from UV rays, mildew and water. It will also help you develop a closer relationship with your Lodge.
*The liner is highly prone to rot along the bottom where it contacts the ground. This is true even for treated cotton, so I always recommend a thinned (50/50) coat of exterior latex paint on the lower 12” to 18” of the liner. This simple step will significantly prolong the life of the liner.
*The poles should also be treated if you live in a damp area, even if you have a treated cotton Tipi. In damp conditions, untreated poles will begin to mildew and transfer that mildew over to the canvas wherever they contact. This will also help retain the beautiful color of freshly peeled poles. I use HempShield® Deck Oil, which is easily applied with a fleecy paint-mitt from the hardware store.