Have you had a new roof put on your home or are you getting one soon? Roofers can create a little-known, but potentially deadly, risk of carbon monoxide poisoning or fire if furnace exhaust vents are not checked immediately after the work is completed. Many homes are space- and water-heated by forced air furnaces or hot-water heaters that burn natural gas. The hot, poisonous fumes from these appliances often are vented outside through sheet metal ducts routed through the attic and roof. A roofer can unknowingly cause these vents to separate when working on the roof above. Often these pipes are just loosely connected; as many as seven of 10 come apart when new roofs are installed. Yet many roofers do not check the attics when they're finished, thus putting the homeowners at risk of deadly carbon monoxide poisoning or fire when hot gases are exhausted near a combustible material. So, if you have a new roof, check old vents to be sure. And that's the On The House tip for today.