Roof Construction Concepts and Techniques

This video tutorial covers the process of laying out and cutting rafters for a lean-to roof. It explains the concept of a lean-to roof, also known as a shed or mono pitch roof, and how it can be attached to an existing structure using a ledger. The tutorial provides detailed instructions on calculating the roof's pitch, total run, diagonal length, and rise using a calculator. It emphasizes the importance of understanding the height above plate and accurately installing the ledger. The video concludes with a demonstration of cutting and laying out rafters using a framing square.

What is another name for a lean to roof?

• Gable roof

• Hip roof

• Shed roof

• Mansard roof

What is the purpose of a ledger in roof construction?

• To act as a decorative element

• To support the roof tiles

• To attach the new structure to an existing one

• To provide insulation

How much does the roof rise vertically for every 12 inches of horizontal run in the given example?

• 8 inches

• 6 inches

• 4 inches

• 2 inches

What is the total run of the new structure after deducting the thickness of the ledger?

• 42.5 inches

• 44 inches

• 45.5 inches

• 40 inches

What is the diagonal length of the rafter for a 42.5 inch run and 4 inch pitch?

• 50 inches

• 40 inches

• 44 13/16 inches

• 48 inches

What does the rise on the drawing represent?

• The rise up to the theoretical measuring line

• The total height of the roof

• The height of the ledger

• The height above plate

What is the height above plate for a 4 inch pitch and 4.5 inch seat cut?

• 8.14 inches

• 7.14 inches

• 6.14 inches

• 5.14 inches

Why is it important to consider the height above plate when installing the ledger?

• To reduce construction costs

• To make the roof more aesthetic

• To avoid incorrect height of the ledger

• To ensure proper insulation

What is the unit run for a common rafter?

• 10 inches

• 11 inches

• 12 inches

• 13 inches

What is the purpose of the birdsmouth cut?

• To provide ventilation

• To add decorative elements

• To fit the rafter onto the wall plate

• To attach the roof tiles