Yes, windows being painted shut is a fire hazard. Because windows painted shut may have locks that stick or cannot be opened easily in an emergency, this becomes an immediate fire hazard that should be dealt with.

No. Removing the cause of concern will only lead to deeper concern. You cannot use any fire-powered appliance like a fireplace or furnace without an escape route for the smoke and fumes. If you remove the flue intending to repair or replace it, you should only use the fireplace, wood stove, or furnace once the flue is in working order. If you cannot replace the flue you have removed, call a chimney repair professional immediately.

Smoke detectors come in two different options: hardwired or battery-operated. While hardwired units are attached directly to the home’s electrical system, a battery-operated smoke detector only needs a simple battery for operation and can be placed virtually anywhere in your home. Some homeowners may mistakenly think their battery-operated units are hardwired in because all their units are interconnected, but many battery-operated units can operate within a smoke alarm network in your home.

You might be able to turn a normal door into a fire-rated door, but you’re better off purchasing one that meets all NFPA 80 standards. If you want to DIY a normal door into a fire door, you’ll need a self-adhesive intumescent seal, metal hinges, fire-resistant glazing, and a self-closing device, but you’re always better off buying a certified fire door.