Q.
a. With the aid of a diagram, label the elements of timber pitched roof. (10 marks)
b. Using diagrams, explain the differences of following types of pitched roof:-
i. Couple Roof
ii. Closed Couple Roof
iii. Collar Roof (15 marks)
(25 marks, 2018 Q4)
A.
a) Timber pitched roof
b) Different types of pitched roof was asked in earlier question but not the exact types here.
Refer to
i) Couple roof
ii) Closed couple roof
This type of roof structure is similar to couple roof (above) but with the legs of two rafters connected with a tie beam. This tie beam hold on to the rafters and preventing them to spread out overturning the walls.
iii) Collar roof - when the tie-beam is raised up to higher level of a closed couple roof.
(Or scissors roof if the collars cross each other)
Ref:
M. Zameeruddin & M. Saleemuddin, Super-structure: Roofs. From Slideshare: