/ Field knowledge · IMC 805.7
A look-alike box is not the listed shroud.
A decorative box on the elevation can become a change to the venting system once it surrounds a factory-built chimney termination. The shroud has to be listed and labeled for that specific chimney system — not a generic UL logo, not a look-alike from another model.
Educational 2024 International Mechanical Code (IMC) 805.7 from Daily Code Talk. Confirm the adopted edition. Distinct from factory-built chimneys (805) and insulation shields (802.8 / 805.8). Install under Section 304.1. This is not a shroud design.
- Decorative shrouds at factory-built chimney terminations are prohibited unless the shroud is listed and labeled for use with that specific chimney system.
- A listing for another model or another system does not establish compatibility. Architectural approval, a generic UL mark, a supplier letter, or a large visible opening does not prove the assembly is the one that was evaluated.
- A cover can change discharge area, wind interaction, heat dissipation, surrounding space, and maintenance access. Verify the approved combination while dimensions and fabrication can still be changed.
On the set: architectural elevation, roof plan, mechanical termination, shroud shop drawing, and chimney submittal must name the same configuration. Custom-fabricated boxes need the actual geometry covered by a documented listed option before the fabricator releases material.
The look-alike from the last roof
Search the architectural set for caps, decorative enclosures, metal hoods, and rooftop boxes. For each factory-built chimney, ask where its specific shroud compatibility is documented. Keep the approved detail in the owner’s record so a future roof repair does not swap in a look-alike.
Source: Daily Code Talk — IMC 805.7 · factory-built: 805 · door swing: 802.9 · heights: 802.5–802.6.
What to send
The architectural elevation with the box, the chimney model, and any shroud cut sheet or shop drawing. If there is none, say so.
If the elevation shows a decorative chimney box
Send the elevation and the chimney listing. Masterbuild will say whether 805.7 even has a listed combination — before the fabricator cuts metal.
Send Project Background+1 (786) 398-6940 · osmany.portal@masterbuildconsulting.com
Masterbuild provides engineering services under a written scope. Nothing on this page is project-specific engineering advice, a code interpretation for your project, or a representation about permit approval. Confirm the adopted edition. This page is 2024 IMC 805.7 education from Daily Code Talk — not a shroud specification. Do not invent a universal shroud-height or opening-area rule. This page is not legal advice.