40 Hour Property and Building Inspection Practice Test

True or False: Purlins are very rarely made from 2 x 4 or 2 x 6 lumber.

1. True

2. False

3. Only for large structures

4. Depends on the climate

The correct answer is: False

Purlins are horizontal beams used in roof construction that support the roof deck and are typically made from structural materials that allow them to effectively carry the loads of the roof above. While purlins can be made from various materials, including steel and engineered wood products, using 2 x 4 or 2 x 6 lumber for purlins is not uncommon. In residential construction, especially for simpler structures like sheds or small garages, it is common to see purlins constructed from dimensional lumber such as 2 x 4s or 2 x 6s. This makes these sizes a viable choice for creating purlins where the roof load and spans are not excessive and can be adequately supported with smaller lumber. The application of dimensional lumber for purlins might be less common in larger commercial buildings or structures with more significant load demands, prompting the use of more robust or engineered materials. The assertion that purlins are very rarely made from 2 x 4 or 2 x 6 lumber is not accurate, as there are many situations where these lumber sizes are used effectively. Hence, the correct answer is that it is indeed false that purlins are very rarely made from these sizes of lumber.