Yes, it will be more expensive to build a tiny home that is off-grid. This is for two reasons:
1. Determining your off-grid needs and designing a utility system that fits your house, your layout, and your unique utility access will take more time than designing a simple plug-and-play on-grid utility system. This means figuring out where and how water holding tanks, batteries, or solar panels will be configured, accessed, and protected from the weather. For some clients, this could be as easy as plopping the units in plain sight and going from there, but for others, this requires careful design and cabinetry to contain the units creatively and utilize every square inch of your tiny house.
2. Going off-grid will plainly mean buying more materials! Solar systems will start at $5,000 and increase based on how much power you need. A solar system that will allow you to be 100% off-grid will likely be over $10k. Holding tanks for water systems will require additional pumps and plumbing pieces that can quickly add up if you will need separate tanks for fresh, gray, and black water. If your off-grid system is being built-in to your tiny house, extra building materials to contain and organize the units will also need to be considered.
Compare all this to an on-grid utility system, which just requires pieces to plug into the electrical grid (basically one large plug) and a hook up for a pressurized water line. Beyond that, all the parts needed to be on-grid will also be needed for off-grid, so there isn’t much difference in design from there.
Check out our website and blog for more detailed information about going off-grid: www.tinyhousecrafters.com/blog