Now it may vary with city or state but the last few home sales I worked all require this.
https://www.google.com/#q=carbon%20monoxide%20detector%20law seems to be a good search on this.
I am planning to get a ulc fire alarm monitoring system which also includes a smoke detector. But is it necessary to install a carbon monoxide detector along with smoke detectors. When I spoke executives from fire monitoring of Canada, they said its always better to keep one. Does any of one of you have carbon monoxide detector installed at your place? Is it mandatory??

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