1. Walk through your home and locate the areas where you want to mount smoke alarms. Smoke alarms should be mounted only inside bedrooms, outside of bedrooms and in hallways leading to bedrooms.
2. Grab your ladder and mount smoke detectors high - on a wall or on the ceiling - though the ceiling mount is preferable, as they will go off sooner.
turn, mount ceiling detectors 4 inches from the wall. Smoke rises, so if you have a odd-shaped ceiling, opt for the highest point on the ceiling to place the detector.4. Avoid mounting smoke detectors near windows or doors, where smoke can escape before reaching the detector.
5. Avoid mounting smoke detectors in kitchens, dining rooms or living rooms. Smoke and steam from cooking, fireplaces, candles and so on can cause false alarms. Basements and garages should be avoided also. Water heaters, fumes from solvents, paint or gasoline, and dust from forced air heaters can set off alarms.
6. Follow the directions on the package for mounting the smoke detector once 
you've chosen the area for the device. You'll most likely need a drill and a screwdriver.
you've chosen the area for the device. You'll most likely need a drill and a screwdriver.7. Make sure a qualified electrician mounts the device if you choose to go with a detector that will be hardwired to your home's electrical system.
You will find every thing you need for installing a Smoke Alarm at your local Expert Hardware store.
