Adding electric lights to a model house will add to the value and enjoyment of your model. The glow of lights will add a sense of realism that will make the exacting care and time you've put into your project even more worthwhile. With the right materials and techniques, you can easily add safe and effective electrical circuits to your model house.
Sketch out the circuits you'll need. If your system is simple, you may have only one light in the house. A large dollhouse, however, might have multiple lights, all located in different rooms. Determine if it's important to have individual control over the lights in separate rooms, for example.
Measure out the amount of wire you'll need for your circuits, and determine where you'll be placing the bulbs in your lighting set up. Light location can be important -- a bare bulb visible through a window can ruin the effect you're looking for. When possible, place the bulbs in spots that are shielded from view yet illuminate the rooms well. A little testing ahead of time can pay off in the end result. As you determine where you'll run the wiring, look for routes that hide the wires from view.
Batteries or power supply? This is an important decision to make. Model house, or doll house, lighting is almost always DC (direct current). These bulbs are small, and the voltage is low. Batteries can be used to power these lights, but they must be replace as necessary. A DC power supply is a better option for most users -- it converts your wall socket's AC current to the DC you'll need for your electrical circuits. If you use a DC power supply, be sure the power output matches the power requirement of your bulbs. Too low and the lights will be dim. Too high and the bulbs will burn out prematurely.
Shop for your supplies. There are several specialized sources for the supplies you'll need for your project. Start with Dollhouse Collectables (http://yhst-4107290884353.stores.yahoo.net/electrical.html), or try Crafts, etc. (http://www.craftsetc.com).
Plan ahead for your wiring needs and save extra shopping trips and frustration