Cob Hybrid in the Caribbean ?

As the subject says I'm looking to build a Cob Hybrid of some sort in the cayo district of Belize and they get alot of rain there along with a temperature of about mid 80 all year round so I just seeing what you guys think as far as straw bale and any other tips and hints to keep it cool without AC.

Hi Christopher,

Cobb is plausible for your region and part of the vernacular as well. Straw bail (SB) maybe a challenge in getting appropriate straw species and then the potential for tropical termite infestation and fungal buildup. One of my main concerns with straw outside of arid regions is fungal decomp from high internal humidity. A "light clay straw" infill application may be feasible also. I have had this conversation with several folks, including a student for southern Belize, my question still is, what is the indigenous vernacular for architecture there? Find out and you will most likely have a model format to build from.

Hi Christopher,

Cobb is plausible for your region and part of the vernacular as well. Straw bail (SB) maybe a challenge in getting appropriate straw species and then the potential for tropical termite infestation and fungal buildup. One of my main concerns with straw outside of arid regions is fungal decomp from high internal humidity. A "light clay straw" infill application may be feasible also. I have had this conversation with several folks, including a student for southern Belize, my question still is, what is the indigenous vernacular for architecture there? Find out and you will most likely have a model format to build from.

Thank you for your quick response. As far as the architectural vernacular I believe all the earthen house building materials are here. I'm just lost on design should I put SB on only the north face or all the way around to keep insulated to prevent the need of ac and for the straw it's self are you worried about a fungus that could exist before or after construction? If standards are met there should be no infestation of any kind.

Have you considered tabby? It's a good material in humid climates, and if you have a ready source of seashells around, you are half way there.

I'v looked into it but don't really like the look of tabby.

Tapia (tabby- thank for suggesting that John) and bousillage are both better alternative than SB in your region. As for aesthetics, they look pretty much the same when finished, as all can and should receive a finish plastering of earth and/or lime. Traditional tapia has indigenous vernacular examples wherever there are large shellfish stock (especially oyster shell) but it is very labor intensive, which if locally sourced and augmented with modern tooling could be feasible in your application.

I am a very big fan of SB architecture, however, I see so many folks jumping on the "bandwagon" of its application that I don't believe they are asking all the questions they should about the application. Mold spore occurs everywhere naturally and all it takes is a humid environment to trigger a response, (like an internal wall void in a 90% humid climate combined with "conditioned air" that can cause condensation.) That still does not speak to the insect infestation that is found in the tropics, that can find there way into a cavity such as SB. Again, I like SB, but am concern with it's application outside of certain environments, especially high humidity tropical ones. It may work with enough planning and forethought but it will not facilitate as well as other wall matrix.

A mass wall structure of some form, with perhaps a timber frame supper structure, and large roof eave overhangs I believe is still going to serve you best if you plan on some form of mechanical "air conditioning. This is perhaps the most applicable style past light timber frame with think woven walls, or mass local masonry walls. Do not use concrete as this has a very large carbon footprint and hold moisture like a sponge, among other issues.

Keep us informed of you progress.

Regards,

jay