Earth Rammed Tyres Links & Thoughts

Over the last few days, having seen so many useful websites on how to build using the methods I am using, I’ve been thinking about how I can make this website more informative for people who are looking to learn more about eco-building.

I’m trying to collate all the information I have gathered into simple posts, so people can hopefully find this one post, and all the links I have, and save themselves a fair bit of time.

I’ve tried to put useful comments by each link so you can get an overview of whats on the page. If you find this page and use it, It would be good to know if you find this useful, please leave a comment!

Please also see my Pinterest page for links to interesting articles.

Earthship Wiki on Tyre Ramming
This page is a pretty filled out resource which details everything you need to know, like selecting tyres, and techniques to follow when laying the courses.
http://www.sustainablebuildingresource.co.uk/wiki/index.php/New_build:earthship:_tyre_ramming

Bristol Green House
I linked to this website on another page, but there is this section, which links to the specific page on tyre ramming. It it a pretty good account of a real tyre ramming project, where the wiki page above documents methods in a more theory based way.
http://bristolgreenhouse.co.uk/tyrewalls.html

My Experience
As I work on my walls, I’ll document more on my experience and post it here.

Ideal Tyre Size Selection:
Currently, I am using 175s (width of the tyre) to build my walls. While the wiki linked to above recommends 195s, am finding that once filled, the tyres bulk out to much wider than their normal width, and the 175s tend to be reliably high profile, so I can get plenty of earth into the rim. For building work, I would heartily agree with the website – 195 is nice and big for holding a lot of weight and take a reassuring amount of ramming to get solid.

My main lesson I have learnt when completing my largest wall – make sure all tyre sizes are the same.

I have collected from a number of garages for this building, and in their eagerness to get rid of their tyres, they have all tried to give me sizes that are close to what I am looking for. E.g. I’m collecting 195/65/15 and they want to give me 195/60/15 or 195/65/16. Initially, I accepted these sizes, but if I were to do the building again, I would refuse. It causes you headaches if your tyres creep out of alignment, which will happen if you do not stick to the same sizes!

Tyre Settlement:
In the process of completing a course of tyres, I have noticed that given a few days of warm or wet weather, the rims of the tyres might settle a little. This could be down to me not ramming enough, or perhaps the type of soil I’m using. Either way, once I have finished a line of tyres, I find it useful to go along the completed row, checking the rims and doing a little bit of extra ramming where needed. Bear this in mind if you have the spare time, as it might help out in the long run.

Cardboard Base:
I only tried this later on in my build, but after seeing a few people use a cardboard insert as a base for the tyre, I think it is the best way of ramming. If you don’t, then as you ram, you get earth falling out the bottom into crevices. This is both difficult to tidy up, and also can cause the tyre to get earth underneath it, upsetting its level. By using cardboard, you get a flat bottom which will be easier to level with other tyres, and tidier to plaster later!

Weather:
While a rammed tyre stands up to rain quite well, and lets it wash off the top, I have found that if you are halfway through a tyre, you will have real problems finishing it, if it has been rained on. The water gets in, and has trouble getting out, and a few whacks with the sledgehammer brings out the muddy mess that has soaked into the earth inside. Try and avoid this by either covering half finished tyres, or by not leaving any tyres unfinished overnight!!

When you build a wall for a building, you need to ensure that it is waterproof, so you should look into installing a membrane behind the wall. This way, you can plaster the interior when you are done and have no issues with water seeping through and getting damp on your lovely walls! This is not so common with the original earthships in Texas, because the ground is so dry, but in wetter climates, it is essential.

In the long run, if you are building a wall which will be exposed, you should make sure that there is something covering the top, to stop any water getting into the tyre, or rain hitting the tyres and wearing away the earth inside over time. I’ve got no evidence myself to prove that this will be a problem, but I’d rather be safe than sorry. Putting a membrane behind the wall and under the first course of tyres also allows you to plaster the wall without any worry that the plaster will get wet from behind.