Between the trend of older parents moving in with adult children and short-term rental earning opportunities, many homeowners are expanding with small detached guest houses that make the most of limited residential space. However, running utilities like electricity to a detached building requires a little extra planning and care due to the unique demands of the space. You'll also need to check local electrical and building codes before deciding how to handle the electrical supply. Use these tips to make the right choices when planning out the wiring and installation with your electrician.
Calculate Required Wire Gauge
Before requesting quotes from any local electrical contractors for running the new wiring, check out some of the raw material costs by pulling up a wire gauge calculator. Since resistance increases over the distance between your home and the detached guest house building, you'll need a higher gauge wire if the structure is far away from the home. Even if you're only running a short distance of wire, you'll also need a higher gauge if you're adding a lot of high amperage circuits to the guest house. Use a calculator that considers both factors to get an estimate of just what you'll spend on wiring before adding in any labor costs.
Consider Buried Installation
It's possible to hang a new main supply wire between your home and the detached guest house, but you may not like the look of a low hanging wire crossing the back or side yard. Burying the wire, especially if you protect it with metal or PVC conduit, clears your view while supplying as much power you as you need for the structure. You can also have trees cut down or trimmed around your property without having to worry about damaging to hanging wires.
Install a Separate Subpanel
Subpanels allow family members or guests to reset their own breakers when they accidentally trip a breaker. It is also the best way to preserve space in your home's main circuit breaker. Check with your local code enforcement office about permitting and inspection requirements for the installation of a new subpanel.
Request a Second Electrical Meter
When you're using a detached guest house as a short-term or long-term rental, you may want a separate electrical meter. This allows the renter to pay their own utility bills, or it at least gives you a chance to keep the costs separate for tax and business account purposes. Your utility company can advise you on the costs and installation requirements for separate metering.
Contact an electrical contractor for more help.