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Flashcards in 11 Roofs Deck (77)
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1

Roofs are water proof and can hinder ladder pipes. If it collapses into the structure it can

Cover fire preventing water from getting to it

2

Three styles of roof

Flat
Pitched
Curved

3

Low slope roof

3/12 pitch, slopes up 3 units for every 12 horizontal

4

Medium to high pitch

4/12 and 12/12,
12/12 is 45 degrees

5

Some bull dings have pitches greater than 18/12 which is too steep to

Work on from a roof ladder

6

Shed roof

Pitches with single sloping aspect, half gable

7

Gable roof

Two inclined surfaces that meet in the middle forming a ridge

8

Hip roof

Same as gable except the gable ends pitch in to meet the ridge line, slopes in fours directions

9

Gambrel

Style of gabled roof where each side slopes at two different angles, used on barns or similar.

10

Mansard

Similar to gambrel and hip. Slopes of two different angles, all sides slope down outside wall. Can have flat roof, modern mansard. Projects beyond wall creating void. Paris style roofs

11

Butterfly

V shaped roofs, like two shed roofs connected at lower edge. Inverted gable looking

12

Monitor roof

Similar to exaggerated lantern, raised section along ridge line providing natural light and ventilation. Large coupola in middle of ridge line. Once common on factories.

13

Clerestories

Vertical walls of coupola of monitor roof, normally operable windows.

14

Sawtooth roof

Common industrial. Used for light and ventilation. Alternating vertical walls with windows and sloping roofs. Windows should face north. Mostly eliminated from modern lighting systems.

15

Curved roofs

Form made from structural systems supporting them. Frequently arches and bowstring truss

16

Lamellas

Vary from 2x8", 3x16", and lengths from 8-14' used to form arched roof

17

Lamella arch

Short lamellas bolted together diagonally using lamellas washers and curvature formed by inclining the ends. Common with gym, auditoriums, sports domes, exhibition halls.

18

Geodesic domes

Formed suing three dimensional triangles

19

Flat roofs are supported by

Joists, I beams, box beams, open web trusses. Of either wood steel, possibly concrete.

20

Inverted flat roof

Main joists at level of ceiling, framework constructed above them to support roof deck. Creates tall void space

21

Rafter(ed) roof, or rafters

Inclined joists used to support pitched roofs. Though trusses can be used

22

Trusses fail under fire load because

Of the reduced mass of their components and interdependence on them to support themselves. Open design allows 360 fire exposure. Plus void space for extension.

23

Fink truss,

pitched residential type truss

24

Monoplane truss

All Chords and diagonal members lie on the same plane.

25

Lightweight wood truss are composed of

Gang nail gusset plates, individual wood members of 2x4 or 2x6, trusses spaced 2-4' on center.

26

Bowstring truss utilizes what for top chord

Curved. Often laminated, top chord.

27

Fink or Pratt style truss

Most common for pitched roofs, made in wood or steel.

28

Tie rod failure of arch

It rod connects between two ends of bottom of arch, failure will result in ends of arch pushing out and failing

29

Wood panel roof decking has minimum thickness of

1/2"

30

Wood plank roof decking has minimal thickness of

1"