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Flashcards in MOISTURE + THERMAL Deck (66):
1

What is the difference between dampproofing and waterproofing?

Dampproofing is protection from water that is not under hydrostatic pressure and waterproofing is protection from moisture and water that is subject to hydrostatic pressure

2

Name five types of dampproofing

Admixtures, bitumous coatings, cementitious coatings, membranes, and plastics

3

What do admixtures do?

Fatty acid, mineral oil, and powdered iron… They may reduce the strength of concrete but they make it much less permeable to water

4

How does powdered ironwork?

Used in admixtures and cemented just coatings, it expands when it oxidizes, making a tighter seal

5

How do you protect waterproofing?

A leak in waterproofing from backfilling is not good… you lay a protective board before backfilling

6

What do you use to seal construction joints?

Waterstops

7

The perfect insulation would be a

Vacuum

8

Most insulation is designed to…

Create air pockets that are small enough to prevent convection but large enough to prevent the direct transfer of heat by conduction between the materials

9

Definition of a BTU

Hey British thermal unit, the amount of heat required to raise the temperature of 1 pound of water by 1°F

10

What does the K value or basic unit of conductance represent?

The number of BTUs per hour that pass through one square foot of a material 1 inch thick when a temper differential is 1°F

11

The long term thermal resistance value (LTTR) is specifically for

Foam insulation

12

What is thermal drift?

The long-term changes in the thermal resistance of foam insulation over time… Measured by LTTR

13

Lues – fill insulation is used for places where…

It is difficult to install other types of insulation, like cells of concrete blocks, plumbing chases, and attic… Also in retrofit applications

14

One of the downsides of loose fill insulation is that it always…

Settles

15

What is rock wool?

A fibrous material formed by blowing molten basalts rock under pressure… Slag wool being the most common, from blast furnace flag

16

Vermiculite may contain…

Asbestos

17

In addition to holding the insulation and place the craft paper on batt insulation does what?

Acts as a vapor retarder

18

Because if it's superior water resistant qualities, extruded expanded polystyrene is the only insulation recommended for what two kinds of spaces?

Protected membrane roof systems and below grade insulation

19

What are insulated concrete forms?

Interlocking foam insulation blocks that serve as formwork for pouring concrete walls and remain in place to insulate the wall and serve as a backing for the chipboard

20

What is a SIP?

Structural insulated panel, to outer skin is bonded to an inner core of residents living material usually expanded polystyrene

21

What is the dewpoint?

The temperature at which water condenses from vapor

22

3 kinds of roofing tile

Slate: expensive, durable, fire resistant

Clay: lots of shapes, durable, fire resistant, also expensive

Concrete: less expensive than clay but also durable and fire resistant

23

5 kinds of metal roof

Copper, galvanized iron, aluminum, terneplate, Monel metal

24

What do you need between the metal roof and the asphalt roofing felt on terneplate roofs and why?

A rosin paper to keep the asphalt from oxidizing the tin

25

Describe ponding

When some build up of water creates deflection, in turn allowing more water to pond

26

What is a built-up roof?

A layer cake of overlapping layers of felt and asphalt or coal tar with a final layer of gravel on top

27

What is a cricket?

A saddle shaped projection around an obstacle to divert drainage

28

What is a pitch pan?

Small metal enclosure around a roof mounted projection filled with bitumous material

29

What are modified bitumens?

A type of single-ply roof made of chemically enhanced bitumen with a reinforcing fabric

30

What are thermoset plastics?

A type of single-ply roof material that softens when hot and regards a when cold

31

What is EPDM?

A manufactured thermoset plastic membrane that can be mechanically fastened, used in a membrane roof, taped together, etc

32

What is the difference between PVC and TPO roofs?

Both white-colored single-ply roofs, TPO is cheaper

Because they are white they reflect back 78% of heat

33

Where do you use elastic liquid roofing?

Over roofs with complex shapes (as well as below-grade waterproofing)

Neoprene is one

34

Some materials you can make flashing out of

Galv. Stl, S.S., alum, copper, plastic

35

How often do you need expansion joints in roofs?

Every 100-150 ft in masonry
Every 200 ft in concrete

36

Why are expansion joints critical in roofs?

Extremes in temperature

37

What are smoke vents?

They allow smoke to escape in a fire

38

High-performance feeling allow what percentage of movement? Low performance sealants only allow what percentage of movement?

High: 25%
Low: about 5%

39

What is EIFS?

Exterior insulation and finish system, a cladding assembly with a wet cementitious finish over a rigid insulation board attached to building sheathing

40

What are the 3 1/2 types of EIFS?

(PB): polymer-based, where the EIFS is basically glued to the building sheathing

(PM): polymer modified, which is mechanically adhered to the sheathing

(MB): mineral-based, where the system uses Portland cement stucco as the topcoat

(A high impact PB system includes a heavy duty fiberglass mesh an additional layer of base coat... But in general the PM system is better at taking impact)

41

What is the difference between permeable and pervious?

Permeable is capable of being penetrated by water without causing rupture displacement. Pervious permits leaks or flows of water through cracks or other openings.

42

What is the difference between water-resistant, water-repellent, and waterproof?

Water-resistant has capillary pores that permit leakage of water. Water-repellent cannot transmit water by capillary action, but it still made transit water under pressure. Waterproof means it is completely impervious to water, under pressure or not.

43

Three damp proofing materials

Asphalt base coatings (in two coats), cement plaster (troweled or pneumatically applied), and liquid silicones or plastics

44

What is the most common form of waterproofing? What form does it usually take?

Membrane waterproofing, usually several layers of asphalt saturated felt, hot mopped together with tar or asphalt pitch

45

Where do you install water stops?

In construction joints below grade

46

A range for tile and slate roof pitch

5:12 - 8:12

47

A range for shingles and metal roofs pitch

4:12 - 8:12

48

Hey range for a bitumous roof
Pitches

0:12 - 3:12

49

What is a square in regards to a roof unit of measure

It equals 100 ft.²

50

What is under the gravel coat in a built-up composition roof?

The flood coat

51

What does shake mean in regards to wood shingles?

Hand split

52

What does 16 – inch 5/2 random shingles mean?

The shingles are 16" long, of random width, and 5 of the butt ends stacked on top of each other are 2" tall

53

Metal roofing materials include what 4 metals? And to a lesser extent what additional three?

Galvanized iron, copper, aluminum and terneplate… Also lead, zinc, and stainless steel

54

Three kinds of roofing tiles

Clay tiles, cement tiles (less expensive), slate tiles (quarried from natural rock)

55

Relative humidity

Expressed as a percentage, this is the ratio of humidity to maximum humidity

56

If air at 50% relative humidity is cool…

It's relative humidity increases

57

What can you do to air to give it excellent insulation properties?

Enclose it

58

Define an insulator in terms of thermal conductivity

A material with a K value of 0.5 BTU per hr per ft.² per °F or less...

59

What are two advantages of placing them insulation above the membrane?

You protect the membrane from temperature extremes and the membrane, being on the warm side of the inflation, acts as a vapor barrier

60

Where to put flashing

Joints exposed to the weather, intersections of different materials, expansion or contraction joints

61

If it's not exposed, you can make flashing from the following:

1. Sheet metals
2. Bitumous-coated fabrics
3. Plastic
4. Other waterproof membranes

62

Provide expansion joints and Masonry walls every ___ feet

125

63

In roofs, concrete structures, and steel structures, expansion joints should occur at ___-foot intervals

200

64

A gravel stop has a higher portion at the perimeter with a minimum of how many inches?

Gravel stop have to be at least 4 inches wide

65

How big are expansion joints?

1/2 to 1 inch in width

66

Four ways to waterproof expansion joints

What are stops, elastic joint sealants, metal flashing, or caulking