Energy Flashcards
Efficient and wise use building materials:
- R_____ and r_____ waste materials
- Products from renewable, recycled, and reused or salvaged materials
- Made with an _______ manufacturing process
- Low manufacturing distance from ________
Efficient and wise use building materials
- Reduce and recycle waste materials
- Products from renewable, recycled, and reused or salvaged - materials
- Made with an efficient manufacturing process
- Low manufacturing distance from building site
What are the three forms of heat transfer? say something about them
- Conduction - Heat transfer by contact.
Thought to move from warm to cool, towards an equilibrium. - Convection- Heat transfer via fluid movement.
Gravity causes cooler, denser fluid to sink and warmer, less dense fluid to float. - Radiation
Heat transfer via electromagnetic waves.
Energy particles moving through space. Or through a room.
What are three ways that a house loses heat?
- Heat transmitted to the exterior through floors, walls, ceilings, windows, doors & penetrations
- Indoor air leaking through cracks in the home’s envelope
- Through air that is deliberately exhausted by bath fans, range hoods, dryers
- When warm water goes down the drain
- When combustion gases from a furnace, boiler, water heater exit via a flue
What is the purpose of insulation?
Works by:
Separating cool and warm surfaces (_______)
Stopping/slowing fluid movement (_________)
Reflecting/absorbing radiation (_______)
(Refers to the three forms of heat transfer
Insulation – Purpose is to slow the transfer of heat
Works by:
Separating cool and warm surfaces (conduction)
Stopping/slowing fluid movement (convection)
Reflecting/absorbing radiation (radiation)
The Number used to rate insulation according to its effectiveness.
What type of value is this called?
R-value
Number used to rate insulation according to its effectiveness.
Stated as R/inch or R/product
R= Resistance to heat flow
Air is an excellent insulator, but the air must not be ___________!
Insulation materials, such as ____glass, are designed to _____ air into small ______.
The more the air pockets and the smaller the size, the ______________
Air is an excellent insulator, but the air must not be able to move!
Insulation materials, such as fiberglass, are designed to trap air into small pockets
The more the air pockets and the smaller the size, the better the insulation
Heat is measured with in ________ .
Higher R numbers are __________
Lower U numbers are __________
Heat is measured with a BTU – British Thermal Units (about the energy in a large kitchen match)
Higher R numbers are better insulators
Lower U numbers are better insulators
THERMAL ENVELOPE
Boundary between conditioned and unconditioned spaces, must be _______ to be effective
Thermal envelope
Boundary between conditioned and unconditioned spaces.
Must be continuous to be effective
Building Thermal envelope consists of what 6 things?
Fenestration ceilings floors walls slabs crawlspaces
Measure of the difference between the average daily outdoor temperature and a specified indoor design temperature, 65 F. What does the above refer to?
A measure of coldness is related to what kind of day?
A measure of how warm it is refers to what kind of day?
degree day
Heating degree day
Cooling degree day
Quantifying Heating Load
The process is continued for every day where average _________________ is below 65F.
Sums of these numbers are often into the _______
Note 75 F is used for design temperature when calculating __________.
Monthly degree-day
- Sum of the degree-days for __________.
Seasonal degree days
- Sum of degree-day for ________
The process is continued for every day where average outdoor temperature is below 65F.
Sums of these numbers are often into the thousands
Note 75 F is used for design temperature when calculating cooling load.
Monthly degree-day
Sum of the degree-days for a month.
Seasonal degree days
Sum of degree-day for a year
BTU = ________________
- Heat needed to raise one pound of water ________
- About the heat in a large kitchen match.
Conductivity
- Measure of a material’s ability to ___________. In terms of Btu’s per hour per SF per 1° F difference.
U factor
- Conductivity through ______________, (i.e. a window)
- A thermo-pane window has two layers of ______ and an ____/___ layer as well as some coatings
R value
- _______ of U factor = a measure of thermal ________
What is the R valve of a material with a U factor of 0.25?
BTU = British thermal unit
Heat needed to raise one pound of water one degree Fahrenheit.
About the heat in a large kitchen match.
Conductivity
Measure of a material’s ability to conduct heat. In terms of Btu’s per hour per SF per 1° F difference.
U factor
Conductivity through multiple layers of materials, (i.e. a window)
A thermo-pane window has two layers of glass and an air/gas layer as well as some coatings
R value
reciprocal of U factor = a measure of thermal resistance
What is the R valve of a material with a U factor of 0.25? 4
Energy code prescribes U-Factor and R-values for seven sections of a building which are?
Energy code prescribes U-Factor and R-values for seven sections of a building.
Glass (skylight & windows are different)
Ceiling
Exterior wall
Floor
Basements
Slabs
Crawl spaces
Not all structures will have all of these areas.
Ceiling SDD < 6500 R – \_\_\_ 12” fiberglass 11” cellulose SDD > 6500 R – \_\_\_\_ 15” fiberglass 14” cellulose
Note if insulation is ___________ at the ceiling/wall intersection R-49 requirement may drop to R-38.
Ceiling SDD < 6500 R – 38 12” fiberglass 11” cellulose SDD > 6500 R – 49 15” fiberglass 14” cellulose Note if insulation is full thickness at the ceiling/wall intersection R-49 requirement may drop to R-38.
Exterior wall
SDD > 6500 R - ___
2x4 studs
2” XPS
3 ½” HD fiberglass (R-13)
R-____
2x6 studs
½” plywood
6” fiberglass (R-19)
R-____
2x6 studs
1” urethane
6” fiberglass (R-19)
R-_____
SDD > 6500 R - 21
2x4 studs
2” XPS
3 ½” HD fiberglass (R-13)
R- 23
2x6 studs
½” plywood
6” fiberglass (R-19)
R- 19.6
2x6 studs
1” urethane
6” fiberglass (R-19)
R- 24.6
