Cement/plaster alternative for walls

[paulindr]

Hi.

Thanks to those who welcomed me to the site. I´ll post a website link once I create a website but, for now, I want to check out views on a particular need.

Again, I live in the Dominican Republic sub-tropics (1200 metres altitude) where days can be hot, nights are cold, there´s plenty of rain for 6 months and then it´s relatively dry.

I´m hoping to build a house and want to reduce the cement content and end up with something very natural looking. I´m thinking of using the very old system of wooden lathes (any type of thin wood strips or thin wooden stems/branches that are interwoven to form a wall full of holes). In England, these were typically covered with lime plaster. Cement will also work but both solutions are not particularly environmentally friendly.

Earth here is not particularly sticky though i may have access to clay (not sure but I think so, though at unknown cost). The finsihed wall must be visually appealing. (Think of hobbit houses as per the film "Lord of The Rings" - though my ideas for the house actually originate about 25 years ago!) I´ve mentioned lathe to local environmental experts and they are worried that such walls may not be sufficiently hurricane-proof to withstand our occassional hurricane interludes (we most get side-swiped but once every few years we get a real hit.

So, any ideas of what would be a good material to cover the lathes (lathes have two sides, inside where it´s mostly dry and outside where it´s often wet!) and any ideas on how to make such walls more hurricane-proof? (The roof is planned to be a wooden structure, lined above with treated wooden tiles and then with a plastic sheet so as to allow local wild grass to be the final cover. The walls will be tied to tree trunks, probably heart of pine, that will be set into the ground - regrettably this probably needs a little concrete as footings but I can´t really see any sensible alternative as contact between wood and earth would surely cause rot.). If the solutions also enhace the hurricane-proof capability of the roof or the house in general, that would be great!

Incidentally, the idea is to create a house based on roundish pods. Each room will be a roundish object, added to the rest realtively informally (there will not be any professional architectural plan). If I need to ascend to a higher level, another round pod can be added if the tree-trunk infrastructure is sufficiently high to support the weight. The land will probably be sloping so a split-level design is anticipated.

Thanks for any suggestions.

[okra]

http://www.cat.org.uk/

[okra]

Hi
had not finished the post, try the link above for The Centre for Alternative Technology, they have an Eco Building section and offer a free consultancy service.

[grahamhobbs]

How were traditional houses in the area built? Did they use any sort of plaster traditionally? If limestone or clay is readily available locally then I am sure they would have used them unless there was good reason not to. I guess you can use cow dung as a binder but I guess you wouldn't really want to.
One thing about lathes is that you need lots of nails and you need wood that splits easy. The plaster for lathes also needs reinforcing, traditionally with 2" long hairs, usually horse hair because they are suitably strong and were readily available. This sort of construction is labour intensive and requires a lot of skill, you could drive yourself mad trying to split those lathes and getting the plaster to 'stick'. My impression is also that people in the sub-tropics do not like cavity type constructions - breeding ground for insects.
Setting timber in concrete will not automatically protect it against rot, the detail needs careful consideration so that water cannot get in.
If there was no suitable soils for building with, I imagine traditionally houses were built completely of timber, then along came corrugated iron. Lately concrete block and plaster have probably started to be used on more expensive properties, possibly using imported cement, etc. This seems the way in the tropics.
As I say, look closely at traditional houses in the area, if they are on 'stilts' then how do they do it. If they dont use plaster, what did they use, perhaps nothing, perhaps in the better houses, tongued and grooved boarding.