Problems with natural earth roof touching ground?

Hello there,

I am currently in the design phase for a 900 square foot timber framed home with cordwood walls and a natural earth roof. My wife is really into having it look like the home is "part of the landscape" by having a roof that touches the ground. I cannot immediately see a problem with this, and google isn't giving me much information besides a bunch of examples in iceland of traditional homes that basically do this. Are there any issues with running the roof all the way to the ground, or a way to replicate this look without running into structural/drainage issues? What ideas do people have for how to realistically do this/explain it to our architect who is drawing up the plans that need to be approved? Thanks for your help.

Hello Joseph,

I will help wherever I am able....

Can this be done? Yes

Is it easy? Well....

First, I don't mean this in a negative way, nor am I soliciting, but if you have an architect and they don't have well versed experience in this type of architecture...well...professionally I think they should have recused themselves for taking this job and your money. If they are doing it for free and the experience...that's a little different.

Yes, there are many ancient vernacular systems from the Athabascan culture and others that have built fossorial architecture as this project is aiming for. As a designer and builder of natural and/or traditional vernacular structures, I have been studying these systems for decades, and find many of the traditional modalities much better and more enduring than the modern. None are easy or inexpensive. I would, even with my experience, see myself having to be very up front with a client about these challenges and probably dissuade them if I could if all I felt was a "romantic attachment" for this modality of building coming from the client. Quite often this style of building is better suited for the wealthy, or the experienced builder...or the very patient and enduring DIYer with serious motivation.

Wofati architecture is the modern interpretation of this and some of done things your size for under a few thousand. These are highly creative, and resourceful folks, that are will versed in salvage and modifying their designs to the offerings of what they can create with two hands, and a sharp mind...with...lots of patients. Earthships are another form. Will these last the centuries and/or millenia that the vernacular forms can...we will see...yet I am doubtful many will, as they rely on to many "experimental concepts" in means, methods and materials. And perhaps too much technology as well, that just don't have a proven track record. I think some will do much better than others, yet these seem to be the ones that are more "old school" than the modern reinterpretations.

Feel free to PM me or send me an email if you would like to delve into this more, or post here. I do insist that I am allowed the ability to bring details back to this thread for others to benefit from, and photos of you progress and sharing blueprints would be really helpful to others as well. I am sure that others here, that actually have built this way and/or live in such homes will share their experiences...at least I hope they will. Please take all advice (including mine) with consideration of the source and the experience of the sharer...there are many "opinions" on this subject...vet the information well...

Regards,

j

Thanks for the reply.

Yes, we have a friend who works in sustainable architecture and is working on us to design our home, and to find the right person to help us with our project, free of charge.

The thing that i'm mostly wondering is what happens when you take a traditional home and extend the roof down to the ground. More than building into the side of a hill as it seems like the wofati design is, I just wanted to do a traditional post and beam home and then extend a natural earth roof down to the ground. Mostly because it looks a bit silly to me to have an earth roof that isn't actually connected to the earth around it. But I'm having trouble conceptualizing this, and also having trouble thinking of what problems we could run into along the way here.

there is one question that leaps to mind for me. The rafters will go to the ground in order for the roof to reach the ground. Each of the rafters will need to be set on a foundation to avoid the problems that come from wood touching earth. How will your design address that issue?

I guess I can perhaps simplify my earlier response (which will have to get detail quick if you actually build something like this) and also address Peter's wise query.

Yes you can build a roof to the ground.

Yes there are traditional modalities of this.

No, it is not easy at all.

Yes, you can do it with modern materials, but durability of them and the methods are questionable.

If facilitated in a traditional format there will be serious stone work and timber framing. Could (can) modern and traditional modalities be mixed to achieve this?

Yes, and again it will require serious stone and timber framing skill sets, plus you are adding "unknowns" with the modern materials augmentation. I lean toward only natural and traditional. If there is augmentation of modernity of any kind, it must be completely independant of the traditional and natural materials, in as such, if these modern materials fail the architecture will not then fail but rely on the "known traditional systems" to work accordingly. It is also very wise to design for "repair and replacement." One of the huge stumbling blocks of most architectural design today is..."entanglement"...

We build too many modern systems in foundation, walls and roofs, from insulation to mechanicals with little thought to "what if" so when one element goes down (heat recovery ventilation as an example) then there is a cascade effect in the other systems failing, often very slowly over time, and not knowing it is taking place...All being exacerbated by lack of easy or convenient replacement through access and modularity.

Much of the ancestral (traditional) systems (ie. stone, clay, timber frame) are the antithesis of "modularity" and "dis-entanglement." Whatever modality of construction is selected:

Look to the vernacular systems for a given area that utilize building resources the most efficiently...

And

Design for serviceability though the process of "modularity" and "dis-entanglement."

Joseph, great question I know I was wondering about this. My dream home has a living roof. It can be seen on youtube, do a search for "cob home" debt free living". There are lots of great ideas in this video, about 4 minutes in a hone with a living roof. It is set on a downhill and has fence which is probably smart, you don't want any 1000 pound cows grazing up there.

Thanks for the tip, what is shown in that video is exactly what i was talking about! Now to just figure out how they get away with that...