Evaluating Homes Built Using Alternative Building Methods

by Nick Gromicko, CMI® and Kenton Shepard

What do you say when you get a call to inspect a home built using a method with which you’re not familiar, such as rammed-earth, earth-berm, "earthship" or strawbale? How about structural insulated panels (SIPs) or insulating concrete forms (ICFs)?

What do you charge to inspect something you don’t know how to inspect?

Do you charge less because you don’t know about this construction method, or do you charge more because you charge according to your level of fear?

The advantage you have in this situation is that when it comes to homes built using these unusual methods, few other inspectors know how to inspect them, as well. Once you’ve learned the secrets of these homes, you’ve added another niche to your business.


You should charge more -- considerably more, even double. Explain to the client that inspecting unusual homes means taking on additional liability. We’ll talk more about that in a moment.

You can also explain that research requirements are greater, which is true.

Lastly, once you’ve done an inspection like this, you’ve usually done more than anyone else around, and so you’ve suddenly become the most experienced inspector in dealing with these unusual homes.


Although, at first, it might seem that inspecting a home built using a method with which you’re not familiar would present high liability, in almost all of these types of homes, understanding them and finding key problems would require you to have been there during construction.

You can’t tell what forming methods were used to form and tamp the walls of a rammed earth home once it’s complete. You don’t know what soil mixture was used.

You can’t tell by looking at the interior wall coverings of a strawbale home whether plumbing pipes were routed through the bales, or installed in a chase beneath the lowest course of bales.

You can’t tell by looking what structural and waterproofing methods were used to seal a concrete dome covered with 3 feet of soil.

These are the reasons that you disclaim those parts of the building that are hidden or which require specialized knowledge. In wanting to provide our clients with good service and value for their money, some of us are hesitant to disclaim important home systems.

You have to be honest with your client and with yourself. Trying to guess your way through an inspection can cost your client a lot of money if you make a mistake -- and maybe not just your client.


When you inspect a home built using unusual methods, give yourself as much time as possible before the inspection. You are going to do some research, and you should include your time in your fee.

Most inspectors do little or no research when they prepare to inspect a conventional home.  Here are some ways to proceed.

  • Do some online research. No matter how unusual the home is, you can usually find information about their construction online. In addition to articles about their construction, you may find contractors willing to discuss the ways that they can fail.

Explain to these specialized contractors that people are hesitant to buy homes built using methods for which there are no qualified inspectors. Educating inspectors can actually increase the contractor’s business.

  • You may get lucky and find information on how to inspect them. InterNACHI has a well-researched article on inspecting strawbale homes.
  • People who build these homes are proud of them and often take photographs during construction. Try to get copies of those photographs, and a set of plans, if possible. Even better is being able to find and speak with the original builder while looking together at the photos and plans.

Ask about any unforeseen problems they had to solve. They often remember the major ones, especially if the success of their solution might not be apparent over the short term.

  • Ask the local building department how they deal with homes built using this method.
  • Some of these homes were sold as kits. Try to find out if the company who manufactured the kits is still in business. If they are, contact them and ask what to look for. They’ll have the same motivation as contractors to talk to you.

Contractors and sales people are so used to talking about how great their methods are that it’s sometimes difficult to get them to understand that you need to learn how these homes are most likely to fail. Even when they understand, they often just can’t bring themselves to admit to any types of failure. Sometimes, you have to talk to three or four people before you get someone who can really be helpful.

Most home buyers will know next to nothing about these homes, but they like the idea of these unusual homes, and that some types can be interesting, comfortable places to live. Sometimes, you’ll have a client who has done some research, and they may have good information, or they may know just enough to be dangerous.

The goal is for you to do enough research that you know more than your client. You want to know more than enough to be dangerous!

If your client is especially knowledgeable, they’ll appreciate the fact that you’ve taken the time to learn the basics. If your client is not especially knowledgeable, it won’t take much to make you look like an expert.

The Inspection

You may want to consider having a specialist contractor accompany you on the inspection. Remember, in addition to the unusual part of the home, there are still the typical systems -- the electrical, plumbing, heating, kitchen, interior, exterior, and so on -- that need to be inspected.

Contractors are not trained as inspectors, so, although you’ll have help with an unusual component, you still need to complete the majority of the inspection yourself.

As you move through the home, also bear in mind that the laws of physics don’t change.

Failure in a specific material will have the same look no matter what form that material is in. Rigid materials that fail by cracking will show cracks. Those that are able to bend or sag will do that when failing because materials that absorb moisture will display moisture intrusion in the same way, whether it's wet drywall, wet concrete, wet soil, etc.


Earth Berm


One InterNACHI inspector was called to inspect an earth berm home, pictured above.  His first questions were:

  • When was it built?

Answer: 1977.

  • What is the square footage?
Answer: 2,800 square feet.


  • Was it a kit or a custom?

Answer: It was a kit. The company was still in business after 32 years. This is always a good sign. It doesn’t take many building failures to put a company out of business. The fact that this company was still around meant that their designs had a good track record, and the inspector could contact them with questions. The main question? “What should I look for?”

  • Were photographs of the original construction available?
  • Were the original plans available?
Answer: Some were available. Neither the photos or plans were complete, but the plans had some of the structural pages showing cross-sections that allowed the inspector to see how the system was designed to work.

Although the information was limited, the inspector was able to get a feeling for the skill level of the builder and his crew by looking at the form and steel work, their equipment, and even the number of people onsite.

Once you know what basic system is being used, the shape in which it’s assembled is less important than whether the workmen were familiar with the materials, and knew how to assemble that system capably and in ways that avoided premature failure. 
The inspector for this berm home did some additional online research, and the inspection proceeded without problems. His fee was $500, and the home took about four hours to go through.



Bales in place

One inspector became interested in developing methods for inspecting strawbale homes, and when he brought up the subject of the lack of inspectors and fire insurance, everyone he met on the jobsite was very helpful.  This home (pictured above) was being built in the inspector's town, so he was able to photograph details and talk to workmen at every phase.


Window detail

If they’re built poorly, strawbale homes can be very unhealthy places to live. Although they first became popular in the early '70s, it wasn’t until the mid- to late '90s that sound construction methods were settled on, good engineering studies were made available, and methods for building them well became better understood.


First coat of mud applied

Although methods still vary, tenets like “no flat roofs” are understood by anyone who has taken the time to research them.  Organizations such as the Colorado Strawbale Association are good sources of information.


Window finish details

This particular home (pictured above and below) had some natural limestone finishes, and it was interesting to learn more about how durable they can be, as well as the fact that the walls of strawbale homes stand up very well to fire. Most strawbale homes lost to fire burn during construction.


The finished exterior walls

These homes can represent high liability for inspectors. Unless you know the contractor and have a lot of faith in them, it's advisable to keep your prices high and take your time with the inspection.  To learn methods for inspecting strawbale homes, read InterNACHI's article on Strawbale Home Basics.


Although inspecting homes built using alternative methods may seem daunting at first, most homes are still built using materials with which you’ll be familiar.

Do your homework, be honest in describing your experience with any particular home type, and disclaim parts of the home that you don’t understand well enough to feel confident inspecting.

Exercise diligence, and these homes can be profitable and interesting to inspect.