Zero Clearance Fireplaces

Another issue is that several of these designs provide a nesting place for birds. Occasionally, screening can be added to prevent this.
Another aspect of these types of fireplaces is that the refractory panels, which form a protective barrier between the fire and metal firebox, can develop cracks in these panels. I might mention that if these cracks are hairline, they are usually not an issue. But most manufacturers of these type fireplaces recommend replacement of panels when crack is large enough to put a coin into crack.





