Buried Monolithic Cabins

[K Harrison]

Been doing some research and a question to ask.

Buried Domes are usually quite large in square footage, but a smaller footplan (and structual integrity of the Monolithic Cabin offered by the smaller footprint perhaps offers a more practical option).

The 'muse' of buried interconnected Cabins (perhaps 3 in total) is a possibility for a future home. But the future site is Texas is the middle of an 'expansive soil' area (in fact Henderson County, Texas). Planning permission/Coding isn't a problem (sometimes Texas is a fantastic place to be, other than the 110 degree summer days).

I've seen threads here about burying the 'domes' (and the problems involved), but has anyone seen the Monolithic cabin buried under 'nice insulating' earth. Coming originally from the UK, I've seen 'buried' Quonset huts (except we call them 'Nissen Huts', lasting 60 odd years since their original construction date). The Insulation provided along with the longevity of the building caused buy burying the thing seem to appeal.

Pretty much looking at an Direct Exchange Heat pump setup buried below the site to help with cooling.

BTW looking at purchasing the 'standard' portable Cabin from Monolithic direct and placing them on site. Beginners/Dreamers question I know, but hopefully some light in the tunnel

[timbau]

Wow

You've a ton of questions. First, I'm a laymen and don't own a dome. However, I've been to many and through the years gleaned some info from my most learned colleagues. Burring a regular dome isn't that big of a deal as long as it's not too deep. They can be engineered to be buried at greater depths by increasing the wall thicknesses. The cabins on the other hand don't have the same thickness of concrete in the walls as the regular dome. I would think this would limit the depth at which they could be buried . I guess it comes down to how deep are your pockets as most anything can be achieved with enough time and resources (money).

I live in Texas and understand your plight of the moving soil. My stick built home had to be renovated because of the soil conditions and a sewer line leak. Dome foundations tend to be the least affected by soil conditions. That doesn't mean that soil conditions don't have to be taken in consideration when building. I do believe that you could work with Jim (Cloud Hidden) or David South to assist you in your endeavors. You may find out that it would be better to use IO20's instead of the cabins for your project.

I hope I was able to shed some light on your inquiry. At the very least given you some place to start and some things to ponder....

[TCLynx]

With the cabins I think the biggest issue would be how to connect them together structurally so that the "tunnel" between them didn't collapse or leak or whatever.
Also keep in mind that doing anything underground is going to add to the price tag a bit simply because building in a big hole will require extra use of digging equipment but there are also added complexities to the structure engineering, plumbing, drainage, and very importantly ventilation. Add to that the loss of windows and natural light. Spend a few weeks with plywood over all your windows and then decide if you really want to live under ground. Some people are fine with it but others are not. With Monolithic domes already being so very energy efficient and durable, burying them doesn't really gain you much in energy savings and what little is gained is probably offset by the additional need for electric lighting and ventilation. So, if you really want to bury the dome home, make sure the other reasons for doing so really do outweigh the reasons not to.

Every situation is different and careful thought to design is essential, don't get too caught up by a single idea that it closes you off to other options. Start off by listing what you need from a home, then add what you want from a home. Draw a word picture about what your home should be for you. Working from there, when you have a site you then figure out how the site and your wants/needs from the home and site can best work together with your budget. Once you have a site and budget is often a good time to work with a designer to work up your word picture about your home and a designer can help clarify those things into a design that could work for you. Insisting they must do it underground might be counterproductive.

[K Harrison]

Well the intention isn't to dig a big hole.

Actually looking at three cabins, and 'mounding' earth over the back and sides as well as the top (Fire Regs mean you have to have outside access). Leaving one wall of each Cabin exposed to the air (westerly facing). The Site has a Creek at the botton, so burying downwards isn't an option. Seen an old home in the UK (now sadly demolished) where a Nissan Hut was buried under about 3" soil that had been piled on top. The owner was pretty sure the longevity of the structure was due to this earth cover (and it was extremely cheap to run). Probably the highest utility bill is down to the AC, so any thermal insulation is a good thing.

The Expansive soil element means a larger than normal pad needs to be poured, which is the perfect time to add the piping for a heat pump. Looking at a low impact/maintainance housing option, and having been in Texas a few years now seen the 'havok' caused by the various lifeforms that seem to be trying to reclaim the state (Fire Ants, Termites, etc).

Was looking at the Cabin for a smaller residence, it merely has to offer 2-3 rooms for a couple getting on in years. But with it being smaller, I'm not sure how thick the poured walls are (remembering to calculate the weight of wet earth if placed on top of the structure). I'll just have to pop over I suppose and see for myself

[TCLynx]

Monolithic construction is certainly well suited to expansive soils and earth berm construction but I think it might be better off applied to a site built structure with the engineering to meet the situation/design you are talking about.

That is not to say you can't berm up around the monolithic cabins, I just don't know what the engineering ramifications would be, like what sort of tie in the cabins would need to the pad to keep the berm from shifting them, etc.

[K Harrison]

Well looking at using the crane lifting lugs to form the tie to the Pad.

French Drains between the Cabins to stop water pooling, the interconnecting corridors probably poured concrete over a form with Silicone sealant for the joins. East Texas usually only suffers 'torrential' rainfall for about 2 months of the year. The expansive soil tends to absorb a lot of mosture, yet dries out fairly quickly. So the challenge is dealing with erosion of the berm, the expansive soil has a tendancy to shift.

Really looking at the possibility of a quick build as cheaply as possible (arn't we all). An alternative to a Trailer and a bit more perminant with lower maintenance. Was looking at a concrete option as any earthworks over the ground level can end up as a giant Ants nest.

But it seems no-one has tried yet (from the first feedback here), so a bit more thought.

[TCLynx]

If you are really after quick, He cabins minus the berms will be quick, energy efficient, and long lasting. Far better than normal manufactured homes.

If you are more interested in the berm part of things, a site build standard model monolithic home with the concrete thickness and rebar upgraded a size might be a better choice.

[timbau]

I have to agree with Lynx, a single dome of appropriate size would be better in the long run that trying to engineer a cluster of the mono-cabins. A 32' dome could be designed with ample space for your requirements. The dome could be buried without adding to the cost of the dome.

Just a thought ....