During an inspection of an existing building, you find that the combustion air ducts are not insulated. What is the minimum R-value required for these ducts, according to Section M1501.3.2 of the 2024 International Residential Code?

ICC M1 exam practice question · Combustion Air

During an inspection of an existing building, you find that the combustion air ducts are not insulated. What is the minimum R-value required for these ducts, according to Section M1501.3.2 of the 2024 International Residential Code?

AR-3
BR-5
R-7
DR-9

Exam tip

Remember that the R-value for combustion air ducts is different from other ducts in the building.

Why C is correct

The correct answer is R-7, as per Section M1501.3.2 of the 2024 IRC. The other options are incorrect as they do not meet the code requirements for insulated combustion air ducts.

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During an inspection of an existing building, you find that the combustion air ducts are not insulated. What is the minimum R-value required for these ducts, according to Section M1501.3.2 of the 2024 International Residential Code?

During an inspection of an existing building, you find that the combustion air ducts are not insulated. What is the minimum R-value required for these ducts, according to Section M1501.3.2 of the 2024 International Residential Code?

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