Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Home Inspection > Envelope > Flashcards

Envelope Flashcards

1
Q

Radon action levels

A

200 Bq/m3

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

How do you calculate total R value when there are some in series and some in parallel?

A

Each section of materials in parallel should be treated as a layer, and its overall R-value calculated. Then all layers can be summed for the total R-value.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Air has a high resistance to this, and a little resistance to this

A

High resistance to heat conduction
Low resistance to heat convection

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

When conduction, convection and radiation occur at the same time, the overall thermal resistance of air spaces becomes this

A

Virtually independent of gap with when it is greater than 1 inch

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

It is most effective when adding layers of insulation in

A

Series, not in parallel. Because in parallel the materials used to divide air spaces might cause what are called thermal bridges.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

The density of material is, the better it will

A

Conduct heat

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Metals and glass have little resistance to

A

Convection

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Describe convection

A

Transfer of heat between objects that are not touching each other. Transferred by means of a fluid such as water or air movement is called convective current.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Difference between permeance and permeability

A

Moisture transmission rate of a material is permeability. (Perm inches)

Permeance is dependent on thickness

Divide permeability of material by its thickness gives materials permeance in perms

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Metric measurement for insulation

A

RSI

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

The three effects of air movement in homes

A

Wind affect
Stack affect
Combustion and ventilation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Will hot or cold water, lower viscosity

A

Heating material lowers viscosity. They permeate faster than cool liquids.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Fungal growth range

A

19- growth continues but can’t start
26- saturation point/growth

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Describe framing factor

A

The extent to which wall roof or floor framing reduces R-value

Wall R-20
Framing factor 25%
=R-15

More framing= higher framing factor

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Two types of building insulation

A

Bulk
Reflective

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Permeance

A

The degree to which material transmits another substance

17
Q

Radon

A

Radioactive gas formed by decay of radium

18
Q

First way heat is transferred

A

Radiation. It can occur in a vacuum unlike convection.

19
Q

What kind of heat flow does radiant heat barriers reflect

A

Reduce downward heat flow because upward he flew tends to be dominated by convection. (better used in hot climates for roofs.)

20
Q

Radon can be breathed into the lungs with a break down further and emit

A

Alpha particles

21
Q

How to calculate, parallel R-value

A

U1= 1/R x area fraction = x

U2= 1/R x area fraction = x

U3= 1/R x area fraction = x

U4= 1/R x area fraction = x

Add them together for total U

R= 1/U

22
Q

Describe R-value

A

Ratio of temperature difference across an insulator and the heat flux (heat transfer per unit area per unit time)

23
Q

Low emissivity windows will transmit these waves, and reflect these waves

A

Transmit light and short wave infrared in
Reflect long, wave infrared radiation

24
Q

Four laws of thermodynamics

A
  1. Heat can either be created or destroyed.
  2. Entropy.
  3. 100% efficiency is impossible
  4. No heat flows between objects at the same temperature.
25
Q

What is U factor?

A

Heat transfer coefficient that describes how well a building conducts heat. Measures rate of heat transfer.

The inverse of R

26
Q

An assembly using foil faced isocyanutate a rigid insulation is classed as

A

Vapour impermeable

27
Q

OSB sheeting and plywood sheathing, covered with building paper or housewrap and vinyl siding are classed as

A

Vapour semi permeable

28
Q

Is lower or higher permeability better

A

Lower

29
Q

Vapour permeance, characteristic of sheathing, cladding assembly is defined by the effective

A
30
Q

4 principle control layers

A
  1. Rain control.
  2. Air control.
  3. Vapour control.
  4. Thermal control.
31
Q

What would a COP3 stand for?

A

coefficient performance times three

3x heat out : heat in

32
Q

Equation for permeance

A

Divide perm inches (permeability)
By thickness
=permeance

Home Inspection (13 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions