3D printed homes could be coming your way but are you trading value for a shiny new object? I’ve been a builder for over 30 years and a prefab & ADU builder for close to 13 years now and it always amazes me when there’s some new technology that creates a paradigm shift in building. Just when you think there’s no way we can improve on a product or method, someone comes up with a brilliant new way and things are never the same again.
Every year at the local and national Builder shows there are tons of new ideas and we spend the better part of each year trying to understand which one’s really make sense. Every new idea is backed by plenty of pretty photos, product literature and a sales force that believes their product will revolutionize the way we build.
Unfortunately most of these products have not been tested in real world environments and that could spell trouble for the consumer once installed. As a prefab builder I can tell you that there are a lot of products out there that have hidden issues that the sales person or glossy sales brochure won’t cover or don’t even know about. For instance, Manufactured homes are a great alternative to site built homes since they are built off-site greatly reducing time and cost of construction. That being said, they are not appraised like a traditional site built home and most lenders do not have the same types of residential home loan packages for them once they are installed. This could leave the home owner with something that’s valued significantly lower than a home that was site built. But, if you use a manufactured home as an ADU it does not have the same negative value issue with lenders since most lenders focus the value on the building method of the primary home. Something you’d like to know before you purchase right?
Another example is Structural Insulated Panels or SIP’s. These are wall panels that consist of high density foam core sandwiched between two pieces of structural sheathing. The panels are built off site and can quickly be assembled to make walls, floors and roof systems at a relatively good price compared to conventional site building, while providing a better insulation & energy performance. What we found out after a wildfire destroyed so many homes is that the foam can melt at high temperatures even if the structure doesn’t burn causing the wall to lose its structural strength. First it’s hard to determine how much of the wall is damaged and then once you do figure that out the walls that are damaged would need to be replaced at a significant cost.
The reason I’m bringing all this up is because 3D printed homes are making their way to the prefab building world and companies are starting to market them as the solution for the 21st century. They might very well be, but we should also think about some of the possible down sides to this before we scrap every other method currently in use. Pulling from the issues associated with Manufactured homes I’d be concerned about how an appraiser views a 3D printed home. Appraisers have a tendency to value things based on the next closest technology, method or product. Will they see it as a sunroom since they are the closest plastic type product in the building world or worse yet not value it like a home at all since they have no working reference of a similar building technology. Something you’d like to know for future resale or refinancing.
How do you run electrical, plumbing and insulation in a 3d printed home since there’s no open framing to hide these items? If they are not printed with the home then the local inspector needs to be involved in the process. When and how will this be incorporated into the build process and is it something the inspector will know how to address? These types of issues are not common so they often end up adding delays to the project while the inspector tries to figure out their role in the inspection process.
How will this hold up over time? Will the years of hot summers and cold winters affect the core product and everything attached to it like windows & doors, roofing and even the foundation. How does it react to extreme heat of a fire, earthquake, flood or wind and will your insurance company provide insurance coverage?
It is important for us to continue to look for ways to improve on the products and processes in the building industry, but not at the expense of providing a sound solution to the homeowner. Sometimes the questions you’re not asking can ultimately be the ones that have the largest impact on the outcome of the chosen solution. Be smart, look for reviews and try to imagine what’s the worst thing that could happen. If you do this you might find enough information to make an educated decision.