Just realized I've swept 1,500+ chimneys this year and only 3 had proper liners

2 comments

2 Comments

The liner situation is way more common than people realize, especially in older homes. Proper stainless steel liners make a huge difference in draft and safety, but most folks just don't know they're supposed to have one. Those unlined clay tile flues can start cracking after a few years of use, and that's when carbon monoxide becomes a real risk in the house.

umac719d agoMost Upvoted

Honestly, clay tile flues actually aren't as bad as some people say if they're in decent shape. But you're right that stainless steel liners are way safer for modern appliances since they seal everything up. The main issue with unlined clay tiles is the mortar joints can crumble over time letting gases escape, not so much the tiles themselves cracking. Still, that's what makes the carbon monoxide risk real when they get old and leaky.