Concept:
A pitched roof is a sloping roof structure commonly used in buildings to facilitate drainage of rainwater and snow.
Timber pitched roofs are constructed using wooden members and are classified according to their shape and construction method.
Some common types include:
• Gable roof
• Hip roof
• Mansard roof
• Batten roof
Step 1: Analyze each option given in the question.
• A. Open Newel roof -- This term is associated with staircase construction, not pitched roofs.
• B. Mansard roof -- A recognized type of pitched roof having double slopes on each side. \checkmark
• C. Fox tail roof -- Not a standard type of timber pitched roof.
• D. Batten roof -- A type of timber roof construction using battens for supporting roofing materials. \checkmark
• E. Deck roof -- Generally refers to flat roof construction rather than pitched roof systems.
Step 2: Identify the correct combination.
The valid types of timber pitched roofs are:
\[
B \; \text{and} \; D
\]
Therefore, the correct answer is:
\[
{B\; \text{and}\; D\; \text{only}}
\]