Construction and Building Materials Multiple Choice Questions & Answers (MCQs) on “Types of Pitched Roofs”.
1. In __________ roofs, the common Rafter are provided to itself without any intermediate support.
a) Single
b) Double
c) Purlin
d) Trussed
Answer: a
Clarification: Lean on roof, couple roof, couple close roof, collar beam roof and collar & Scissors roof are the some varieties of a single roof.
2. ______________ is the simplest form of a pitched roof and it is also known as pent roof.
a) Collar beam roof
b) Collar and scissor roof
c) Couple roof
d) Lean on roof
Answer: d
Clarification: In Lean-on roofs, one wall is carried up sufficiently higher than the other one to give necessary look to the roof. The Rafters are suitably secured on the wall plates and eave boards, battens and roof covering are provided.
3. In ________________ roof, the common rafter slope upward from the opposite wall and they meet on a Ridge piece in the middle.
a) Couple-close roof
b) Lean-on roof
c) Collar beam
d) Couple
Answer: d
Clarification: In Couple roofs, the common rafters are firmly secured in position at both the ends, one in being on the ridge piece and the other on the wall plate. Such a roof is not very much favoured because it has the tendency to spread out at the feet.
4. __________________ roof is just similar to a couple roof except that the legs of the common after are connected by tie beam.
a) Collar and scissor
b) Collar beam
c) Couple-close
d) Couple
Answer: c
Clarification: In Couple-close beam, the tie beam prevents the tendency of rafter to spread out and thus the danger of overturning of the wall is avoided. The tie beam can also be used as a ceiling joists when required.
5. __________________ roof is a variation of a couple close roof.
a) Collar beam
b) Collar and scissor
c) Tie beam
d) Lean on
Answer: a
Clarification: The tie beam is then known as a Collar or collar beam. A collar beam roof is adopted to economise the space and to increase the height of the roof. The collar beam is usually fixed at one third to one half the vertical height from the wall to the Ridge.
6. ____________________ roof is similar to the collar beam roof accept that two collar beams which are crossing each other to present an appearance of scissors are provided.
a) Collar and scissor
b) Collar beam
c) Tie beam
d) Lean on
Answer: a
Clarification: Whereas, Lean-on roof is generally used for sheds, out houses attached to main buildings, varandahs, etc. It is suitable for a maximum span of 2.4 metres.
7. In order to reduce the size of rafters, the intermediate support, called the ___________ are introduced under the rafters.
a) Couple roofs
b) Purlins
c) Tie beam
d) Collar beam
Answer: b
Clarification: When the span exceeds about 2.4 meters, the necessary size for the rafters become economical. Hence double or Purlin roofs are provided in such cases.
8. When the span exceeds 4.8 M and when there is no inside supporting walls for Purlins, the frame structures adopted, known as the _____________
a) Single roofs
b) Purlin roofs
c) Double roofs
d) Trussed roofs