It's a fact, smoke detectors save more lives every year from fire. You should also install them near furnaces, hot water heaters and gas heaters. Install them in the hall near the bedrooms and kitchen.
Smoke detectors come in many styles and two different types.
There is the smoke detector that works off batteries, which have to be replaced every 3 months to make sure the batteries are fresh and the smoke detector is in tip-top shape. Then there is the smoke detector that hooks up to your electrical wiring in your home. This one is great because you don't have any batteries to change, but if there is a storm and you lose power, you also lose the power of the smoke detector. You can have your electrician install the wired smoke detector. The battery smoke detector just requires a plate attached to the ceiling and either 2 AA Batteries or a 9 Volt, depending on who manufactured yours.