CLTD Roof & Wall Number

Instructions:

Review the methodology to ensure it aligns with your project's requirements.

Roof:

1. Enter the Roof Type

2. Enter the Mass Location

3. Enter the Insulation R-Value

4. The CLTD Roof Number will be shown in the CLTD Roof Number box. 

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Wall:

1. Enter the Wall Material

2. Enter the Mass Location

3. Enter the Secondary Wall Material

4. Enter the Insulation R-Value

5. The CLTD Wall Number will be shown in the CLTD Wwall Number box.

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Methodology:

This calculator is based on the 1997 ASHRAE Handbook, Fundamental, Table 31, page 28.42 for Roofs and Tables 33A, 33B, and 33C for Walls.