Earth Sheltered homes are “non-standard”. In many ways, this is a good thing, but, unless you are out in some “wild-west” part of the country where there are no building inspectors, you will still need to meet standard codes. Many existing earth sheltered homes are built to code, so it is doable, but it does take some care to understand those codes and to understand their intent.
I think I am prepared, but I am just getting started, so I may be naive. I will be back to discuss lessons learned working with my building inspector. So far, things have gone a bit smoother than I expected.
Also understand that the codes make allowances for new ideas or “alternatives” if the building inspector can be convinced that they will be sufficient. To find these exceptions, pull up a PDF of your codes (plumbing codes or mechanical, etc.) and search for the word “alternative”.
You will find sections like this that I found in the mechanical code…
105.2 Alternative materials, methods and equipment. The provisions of this code are not intended to prevent the installation of any material or to prevent any method of construction not specifically prescribed by this code, provided that any such alternative has been approved. An alternative material or method of construction shall be approved where the code official finds that the proposed design is satisfactory and complies with the intent of the provisions of this code, and that the material, method or work offered is, for the purpose intended, at least the equivalent of that prescribed in this code in quality, strength, effectiveness, fire resistance, durability and safety ~ Mechanical Building Code
This means that it is up to the inspector to carefully consider your proposed design and approve it if it complies with the intent of the building code, which is generally safety. They shouldn’t just refuse your permit or ask you to make changes because they haven’t seen it done that way before or because it is not specifically in their code books. However, it may be up to you to provide the proof that your design is a good one. In my particular case, my inspector didn’t feel like he was qualified to decide if my shotcrete structure was adequate or not, so he asked me to provide engineered drawings. You will find sections of the code (such as 304.4.3 of the Mechanical code) that allow for alternatives if they have been “specially engineered.”
Researching and/or meeting up with the local building inspector is a great idea before buying land to build your earth sheltered home on. I met with my inspector and showed him my rough drawings before I bought land in his township. He seemed open minded to the earth sheltering idea and told me that he saw his job as making sure my home was build safely and that my contractors didn’t cut corners. He clearly put himself “on my side”. He even told me about other earth sheltered homes that had been built in the area. Had I anticipated an uphill battle against a negative mindset, I would have moved on and looked for land elsewhere.
If your inspector will not let you use a good design that you can show is “safe”, then they are being “arbitrary“, which is a legal term that gives you the right to appeal. The appeals process doesn’t need to involve lawyers or lots of money or time, but make sure that you bring the evidence that what you are doing is safe…
And stay polite… You need show that you know what your are doing so you can remove the impasse and continue with your build, but you don’t want to poison your relationship with the inspector, and possibly everyone in his office. Often the threat of an appeal will be enough to convince your inspector to more carefully re-consider your supporting evidence.
In many cases, you will find that “code” is well short of the kind of home you would like to bring your family into. Earth sheltered home owners should be interested in going beyond code in a number of different areas, including electrical and waterproofing. More on this later.