Interior Flashcards
1
Q
Is air a good insulator
A
Yes but only if it does not move. Heat moves with air
2
Q
What is R-value
A
Resistance to heat transfer per 1 inch thickness
3
Q
Recommended insulation R-values in attics walls and overhead spaces
A
R 40 - 60 in attics
R-17 in walls
R-27 in overhead spaces
4
Q
What is cellulose fibre
A
Paper shredded and chemically treated insulation. It absorbs water easily
5
Q
What is plastic board insulation
A
Poly styrene or polyurethane
6
Q
Describe vermiculite insulation
A
Mineral made from MICA (loose fill)
Small rectangular pieces
Noncombustible
Brand Zolonite contained asbestos
7
Q
What are the less common insulation materials
A
Leather, gypsum, slag and cork
8
Q
What temperature should the attic be
A
Same as outdoor temperature
9
Q
What is the problem with uninsulated ductwork in attic space
A
Heat loss and condensation problems as it cools
10
Q
When should you insulate the roof in an attic
A
Only when air leakage cannot be easily controlled
11
Q
What should be done to skylight well walls
A
Well insulated and has air vapour barrier on warm side
12
Q
What should be done to exhaust ducts in attics
A
Insulated
13
Q
Is all ductwork non-insulated
A
No. Some comes pre-insulated not visible
14
Q
Insulation is not effective when
A
It is wet
15
Q
Why does compressed insulation lose effectiveness
A
Air is removed
16
Q
What can happen when the bathroom exhaust fans connected to uninsulated ducts in the attic
A
Warm moist air from the bathroom condenses on the inside of the ductwork. It runs back down and drips past electric motor
17
Q
What happens when recessed lights are covered with insulation in an attic
A
Can start a fire. Barriers with 3 inches of clearance should be provided
18
Q
What is an insulation short circuit
A
Insulation added to the exterior of wood frame wall without adding insulation in the stud cavity allows heat to escape through the top of the stud wall due to convective currents
19
Q
Masonary walls usually have what between layers or in the course of the block
A
1 inch space
20
Q
What is most heat loss due to
A
Air leakage
21
Q
What is sometimes added against outside of foundation walls
A
Moisture barrier
22
Q
What is added to the inside of foundation walls
A
Air vapour barriers
23
Q
Does the insulation in the basement or crawlspaces go all the way to the floor and why
A
No it stops 8 inches above the floor to ensure the foundation wall does not freeze
24
Q
Does fibreglass insulation have a higher value in bat form Or loose fill
A
Batt form
25
Insulation let’s some air and heat through. What do air barriers on either side do
Reduce air movement and prevent wind washing
26
How do vapour barriers reduce vapour movement
Vapour diffusion
27
What is vapour diffusion
Tendency of water vapour to move from areas of high humidity to low humidity
28
As air temperature drops what Happens
Relative humidity goes up
29
In cold climates what is required on the warm in winter side of insulation and why
A vapour barrier to stop vapour moving from the house to insulation
30
What is housewrap designed to do
Reduce windwashing
31
Air barrier is also called
Membrane
32
What does a membrane or air barrier do
Stops air but allows migration of moisture (vapour diffusion) Towards area of lower vapour pressure
33
Do vapour barriers need to be continuous
No
34
What are common as air barriers and vapour barriers
Clear polyethylene sheets
35
What are often installed as air barriers
Synthetic house wraps. They allow vapour to pass through so they can be on either side of insulation
36
What can replace sheathing paper
Synthetic house wraps
37
Many oil based paints, varnishes and shellacs act as
Vapour barriers
38
Why can vinyl wallpapers be a problem in warm climates
They are vapour barriers the wrong side of insulation
39
What does aluminum foil on insulation do
Acts as a vapour barrier and a radiant barrier to reflect heat
40
Some types of plastic insulation are
Vapour barriers. Foamed in and rigid boards
41
Can insulation boards be Air barriers
Yes. If joints are well taped
42
Potential air leakage locations in attic’s
Around chimneys and ducts, access hatches, wall or ceiling intersection, exhaust fans and duct partitions, light fixtures
43
Recommended attic ventilation rate
One square foot of ventilation for every 300 ft.² of attic floor
44
Describe roof vents
Account for 50 to 80% of total venting
Screens for insects and birds
Located high on downwind side of house to create a draft up through eaves
45
What are baffles used for
To keep soffit vents clear of insulation
46
If there is no air vapour barrier and no soffit vents in the attic what is the minimum ventilation rate
It is doubled to one square foot for every 150 ft.² of attic space
47
Why are turbine vents not recommended in attics
The only work on windy days when they are not necessary
48
Why are power vents installed in Attics
For some are used to remove hot attic air.
49
Why are power vents not recommended for cold weather
They put attic under negative pressure and draw more warm moist air from the house
50
Ideally where are vents located in the Crawlspace
Within 3 feet of the corners
51
Earth floors in crawl spaces should be
Covered with a sealed plastic sheet
52
What are heat recovery ventilators also called
Air to air heat exchangers
53
What do heat recovery ventilators do
Transfer some heat From stale exhaust air to incoming called outdoor air
54
Why are exhaust ducks sloped down from heat recovery Ventilators
To drain condensation
55
Where is air usually taken from in heat recovery ventilators
Kitchens and bathrooms because they are stale and humid
56
Where should intake and exhaust hoods be with heat recovery ventilators
6 feet apart in 3 to 4 feet from corner of the building
57
Where should Intake hood be on heat recovery ventilators
18 inches above grade and 3 feet away from metres and Vents
58
What should be below concrete floors to allow water to drain
4 to 6 inches of gravel base
59
Are most concrete floors part of the structure
No. They are installed after Home is completed usually
60
What is a hardwood parquet
6 inch squares with checkerboard effect
61
Describe hardwood strip flooring
Tongue and groove, nails driven diagonally
62
Bottom of laminate floors maybe
A paper or melamine backing
63
Engineered wood floors are similar to laminate flooring, except
Top layer is hardwood
64
What kinds of soft wood floors are used
Pine is most common. Fir and cedar are also used
65
What is carpet made of
Wool blended with a synthetic material
66
What is brittle floor tiles cracking usually caused by
Floor system that is not stiff enough
67
 Why should you be careful with ceramic tile floors
Some are only intended for a wall use
68
What is the difference between plastered and drywall
Plaster is applied with a trowel on site (made of gypsum)
69
Older plaster and wall systems have wood lath bases which are called
Yardsticks
70
Drywall is also called
Wallboard, sheet rock, plasterboard and Jip rock
71
Removing plaster from inner face of exterior brick wall does what
Reduces insulating value
72
When does nail popping happen in wall finishes
Stud shrink in nails Pop out
73
Kinds of trim
Baseboard, quarter round, Cherry Hill, plate real, cornice molding, door and window trim
74
What are cornice mouldings
Mouldings at ceiling/wall intersections
75
What is broadloom carpet
Wall-to-wall
76
What are pieces of Glass in the window called
Panes, Glazing, or lites
77
Panes of glass are held in a
Sash
78
When panes of glass are divided in a sash, what are the pieces called
Muntins
79
This separates two or more windows where they open
Mullion 
80
What is added in between panes of glass
Gases with lower thermal conductance
81
Describe tempered glass
3 to 5 times stronger by heating it and cooling it very quickly
Safer because it breaks into rectangular pieces
82
What happens when sash chords on single and double hung windows are painted
They become in operable
83
When may double or triple glazed windows collect condensation
When a seal has failed
84
Why are window sashes and frames susceptible to condensation problems
Because medal is a good thermal conductor
85
Window systems with a primary and storm window have what below outer pane
Drain holes
86
Common problem with manufactured window systems
Poor connection at sil/jamb
87
What does caulking on the inside and outside of windows do
Outside prevents water penetration
Inside prevents air leakage
88
What are acrylic panes of glass sensitive to
Scratching damage from cleaners or branches
89
Why do skylights installed on curbs 4 inches or higher above platform perform better
Better flashings
90
Why are skylights prone to leakage
They are often installed after construction so holes are cut and there are structural considerations
91
Solarium glass used in anything other than a vertical plane should be
Strengthened by tempering or laminated
92
What are transom lights or fan lights
Fixed windows above doors
93
Which type of doors expand and contract the most
Fibreglass
94
How is condensation reduced in modern sliding glass doors
They include a thermal break between inner and outer halves of the metal frame which keeps the inside of the frame warmer
95
Describe the French doors
Hinged on outside, mostly glass, broken up into several panes by muntins
Meet in the middle with no mullion or frame
96
When sliding glass doors are installed in a new wall opening, what is required
A substantial header Above the opening to carry the wall load
97
Garage man doors should
Protect from fire in fumes and have an automatic closer
98
What is the problem with adding a storm door to an insulated metal door
The space between doors can become overheated and plastic mouldings made deform and the doors may buckle
99
What are staircase components called
Stringers, treads, risers
100
Describe stair nosing
Front of tread extends 1 inch beyond riser below
101
Maximum rise for stairs
8 inches
102
Maximum run for stairs
8 1/4 inches
103
Minimum width for stairs
36 inches
104
Minimum headroom above stairs
6 1/2 feet
105
Doors at top of stairs should
Open away from them
106
Where is rot common on staircases
Bottom of stringers
107
Types of tread/stringer connections
Rooted, cleats, notched
108
Why are fireplaces not always energy efficient
They provide radiant heat into a room but consume warmed house air for combustion and draft. Warm house air goes up the chimney
109
A fire can draw how much air out of the house per minute
300 to 400 ft.³
110
Describe woodstoves
Enclosed units and more energy efficient than fireplaces
111
What problems do chimneys have that are exposed to cold outdoor weather face
They have trouble establishing good drafts
112
What is creosote
A tar like substance build up in chimneys that is a fire hazard
113
Do all natural gas fireplaces require a chimney
No. Some modern ones do not
114
What kind of mortar should the mortar joints in fire brick be
Special refractory mortar
115
Why is no mortar required in the fire brick on the hearth
Bricks are not likely to move
116
Fireplace components
Cap, liner, smoke chamber, smoke shelf, damper, throat, firebox, hearth, Ash dump, Ash pit, Chimney clean out
117
Metal fire boxes can fail by Bowing or buckling which is a result of
Inadequate clearance between metal and masonry
118
A metal fire box should not be confused with
A zero clearance fireplace or fireplace insert
119
Should dampers be kept open
No. They should be kept closed When the fireplace is not used to minimize heat loss
120
Clay tile liners are section 2 to 3 feet long with
Mortar joints
121
Fireplace mantels should not have combustible materials within
6 feet
122
Heat circulators are also called
Heatilators
123
How do heat circulators work
Used masonry channels or a crude duct system to draw cool air from low and out through vents higher
124
Masonry fireplace problems
Cracked hearths, Deteriorated fire brick, inadequate clearance From combustibles, openings, Creosote
125
How far should hearths project
16 to 20 inches in front of firebox and 8 to 12 inches beyond either side
126
Causes for poor fireplace draw
Chimney too short, flu too small, opening too large, poorly shaped firebox, damper too small or far back, poorly shaped smoke chamber, excessive offset in flue
127
Metal fire boxes should be half an inch away from masonry with
Noncombustible insulation
128
Can a wood burning fireplace share a chimney flue with any appliance and why
No. Products of combustion may enter the house through the idle appliance flue
129
Can a furnace in the basement share a flue with a fireplace above
Yes
130
A masonry façade may pull away from the wall due to
Floor sagging from the weight
131
What should you check at the top of the chimney for
To make sure the divider is intact. Exhaust products could get back into the house
132
What do zero clearance fireplaces have
A damper but usually no smoke shelf
133
What are required with fireplace inserts
Stainless steel continuous liners
134
What are gas fireplaces that are designed to fit into masonry fireplaces called
Inserts
135
Fireplaces in bedrooms or bathrooms must be
Direct vented
136
Where gas logs are installed in an existing fireplace, The damper must be
Permanently opened for exhaust to go up the chimney
137
What floors do woodstoves sit on
Concrete floors or protected wood floors
138
Can woodstoves share a flue with appliances
No
139
What are breechings in fireplaces
The pipes that join the stove to the chimney
140
Requirements for flue pipes or breechings
No more than 10 feet of horizontal run, no more than 2 90° elbows, supports every 3 feet, joints that allow condensate drain into stove
141
Minimum flu slope from stove to chimney
Quarter inch per foot
142
What is a flu/chimney connection made with
A thimble or flue ring
143
creosote Can be more of a problem in
Woodstoves due to the slow burning
144
Does more efflorescence on concrete floors mean more water leakage
No. More deposits come from drier air and greater rates of evaporation
145
Efflorescence in basements may be the result of
Outside the water passing through the wall, condensation, or water wicking up through the wall by capillary action
146
What happens with exterior drainage tiles when basements are lowered
They become ineffective. Interior drainage tile should be provided below the new floor
147
How much of basement leakage problems are caused by groundwater and how much by surface water
10% ground water. 90% surface water
148
What is the problem with P traps outside
They can freeze in the winter
149
Where good grading cannot be achieved what are used
Catch basins
150
What do catch basins do
Carry water to drainage systems. They clog and are susceptible to heaving
151
What is the best material for patching cracks in concrete
Epoxy
152
Why is interior patching not effective for hollow block walls
Too many paths for water
153
What prevents leaks on the outside of the foundation
Dimpleed plastic membrane, drainage tile and gravel fill
154
What kind of fabric wrapped around drainage pipes keep soil out in let’s water in
Geotextile fabric
155
Where do drainage systems ideally discharged to
Storm sewers
156
What is damp proofing
Parging concrete block walls with quarter inch layer of mortar extending down to the footing, which is coved (sloped) To direct water to drainage tile Then a damp proofing layer is applied to the wall
157
Houses are not built below water tables but what happens with rainfall
they may rise
158
Where should smoke detectors be provided
In all sleeping areas of the home and on each floor
159
Where should CO detectors be
In every room with a wood-burning appliance And ideally on every floor
160
Detectors should be tested how often
Monthly and batteries replaced annually
161
How often should detectors be replaced
Every 10 years
162
Chimney flue liners are what material
Metal or clay tile. They are continuous and airtight from heat source to outside
163
Exterior chimney inspections focus on
Flashing and mortar joints
164
Interior chimney inspections focus on
Chimney pad, settlement and structure
165
Are masonry chimneys usually part of the foundation
No. Footing is independent of foundation
166
Uneven settling of chimneys may cause gaps. What should be done
Filled with in elastomeric caulk
167
Exterior cracking in a chimney can lead to
Flu cracking – fire hazard
168
What does a lot of efflorescence at the top of the chimney suggest
Water has been running down the inside for years because a mortar cap has failed
169
Chimneys must be 3 feet above
Roof on the chimneys upslope face
170
What do mortar caps do and what are found often in them
Shed rain. Cracks often form
171
Should you vent a fireplace and furnace or any heating appliance in to the same chimney flue
No. Carbon monoxide from furnace could enter living spaces
172
Peaked rain caps are also called
Wash caps
173
Wash caps are often installed above mortar caps for what purpose
To keep Creosote from running down the flue
174
Codes may require what on top of Chimneys
Spark arrestor’s
175
Most Chimneytop dampers are operated by
Steel cables that hang down the flue
176
How often should chimneys be cleaned
Once a year
177
How is flashing done on Chimneys
Counter flashing is tucked into mortar joints and base flashing is free from nail holes
178
What is often used to patch Chimney bases
Asphalt roofing cement
179
What do parge corbelled bricks do on fireplaces
Protect mortar and facilitate cleaning
180
What can smoke stains indicate with fireplaces
Poor draft or someone left a damper closed during a fire
181
What are some smoking fireplace fixes
Smoke hood, fireplace doors, convection ducts, purging, burn Drywood, Clean fireplace and chimney, rebuild firebox
182
Black drafting in fireplaces in air tight homes happens when
Fans are used. When a damper is open, then air rushes back down the chimney causing smoking
183
No combustible material is allowed within how far of a fireplace
6 feet
184
Are all gas fireplaces vented
No
185
Is it safe to burn anything other than gas in a gas fireplace
No
186
Vented gas fireplaces have what piping
Concentric vent piping whose outer pipe draws in outside air for combustion and it’s inner pipe vents combustion gases outside
187
What do unvented gas fireplaces have
Thermal sensors and oxygen depletion sensors
188
Why do dampers in vented gas fireplaces have to stay open
To prevent CO in living area
189
What should be installed in rooms with gas fireplaces
CO monitors
190
What may be the cause of a woodstove leaking creosote from stove pipe joints
An installer may have crimped the male pipe and toward the chimney symbol rather than the collar
191
What is a collar also called in fireplaces
Takeoff
192
Why must woodstoves be air tight
Gaps could leak combustible gases into living spaces
193
Describe a fireplace insert
Wood burning stove inserted into a fireplace, metal flue pipe installed in chimney, terminating above roof.
194
Wood stoves should be at least 36 inches away from combustible surfaces, but can be 12 inches away if this is installed
A metal shield with a 1 inch air gap
195
Can a stove pipe connecter pass through walls
Fuck Nah
196
What are the differences in how drywall and plaster feel
Drywall smooth plaster has a slightly gritty feel
197
What may be the cause of nail or screw pops in drywall in gaps at the tops and bottoms of walls
Green lumber may have been used rather than kiln dried lumber
198
What might be the cause of isolated bulges in walls
Studs have twisted due to green lumber being used
199
What might be the cause of widespread nail or screw pops in ceiling
Attic joist flexion from undersized joists
200
What is common along wall – ceiling joints on exterior walls if a roof is framed with trusses
Cracking during seasonal fluctuations
201
Diagonal cracks from windows or door corners indicate what
Structural movement
202
Large cracks that slope Towards the base of the wall indicate
Inadequate support beneath wall
203
Condensation and water stains around windows indicate
Interior moisture or insufficient ventilation in the attic
204
What is the issue with cracked heat exchanger’s and leaking furnace ducts
They can dump water vapour which is a byproduct of combustion into living spaces
205
Plaster that uses through a lath is called
A key
206
Purple – pink blotches on wallpaper indicate
Mold. Mould loves wallpaper
207
Where is a good place to look for water stains, cracks, lead paint etc.
Closets
208
When was Lead paint banned And is it a problem to have
1978. If it is not flaking or peeling, there is little chance of inhalation
209
What is interior trim also called
Casing or moulding
210
Should there be gaps at the corners of interior trim where pieces meet
Yes. Because wood shrinks
211
Why are gaps under baseboard trim common
For expansion and contraction
212
We’re trim tilts downward in one direction and is accompanied by diagonal cracking at door and window corners, what does this indicate
Structural distress
213
List interior trim names from top to bottom
Crown molding, picture molding, chair rail, baseboard
214
What are usually the last materials to be installed in the house
Flooring and base moulding
215
How should you ascertain the thickness of wood flooring and sub flooring
Remove a forced hot air register and look at the exposed cross section of flooring
216
What should a home inspector do if carpet has been newly installed over wood flooring
Ask homeowners to verify in writing that floors are in good condition
217
What does cupped hardwood flooring indicate
Underside has absorbed moisture
218
What does flooring that bows in the centre of the room indicate
May have been installed without a gap in its perimeter to allow for expansion
219
What does localized springiness in floors indicate
Undersized footing pad or deteriorated or Absent post beneath the girder
220
What does widespread Floor springiness indicate
Joists too small for span or field or absent girder
221
Flooring that crowns above a girder indicates
Failure of the perimeter foundation
222
Why is carpet installed over slab problematic
Moisture can wick through concrete
223
Why is sagging on the open side of a staircase common
Because there are no wall studs to bolt to
224
What do cracks at the top or bottom of the staircases indicate
Centre of carriage has pulled free from doubled header
225
What are headers and what are they supported by
Lentils are bearing beams that are supported by King studs which are full length and a shortened Jack stud
226
What do cripple studs do
Transfer loads from walls top plate to Header
227
What are cripple studs also called
Dragon’s teeth
228
What are jack studs also called
Trimmer stud
229
How high should interior and exterior doors be
6’8”
230
What is a Mullion
Vertical divider
231
How much overhang should be over exterior doors
At least half the distance from doorsill to eaves
232
To minimize warping, Panel doors have
Engineered wood cores
233
Average R value of doors
Wood= R-2
Steel doors= R-5-6
Fibreglass= R-8
234
What is a “kerf”
A slot milled into the door frame for weatherstripping
235
What is weatherstripping at the bottom of the door called
Shoe or sweep gasket
236
What can be retrofitted over door threshold in areas with lots of precipitation
Water return thresholds
237
water return threshold components
Drain pan, weep holes, Vinyl seal, metal door shoe, strip bar
238
Windows at the bottom of the staircases must be
Tempered glass
239
Where does rot usually start on windows
At the bottom of the sash- windowsill juncture on wood frame windows
240
If an egress window has security bars what must they also have
Release mechanism inside
241
All kitchen outlets should be
GFCI protected
242
Kitchens should have how many small appliance circuits
2×20 amp
243
How often should there be outlets at kitchen countertops
Every 4 feet
244
Does a bathroom heater need its own circuit
Yes
245
Should major appliances be GFCI protected
No. Large motors may cause a nuisance tripping because they have large starting loads
246
What do flickering lights indicate
An overloaded circuit
247
Rangers need 120/240 V sometimes. what is the wiring for that
Too hot wires, neutral and ground
248
Older dishwashers vent through
A chrome cap above the sink
249
New dishwashers have anti-backflow or
Airgap devices
250
What is the problem with an oversized hood over a range
They can expel so much air that they create back drafting. Negative in-house air pressure draws furnace or fireplace exhaust from chimney
251
Range hoods also exhaust what
Airborne grease that might otherwise cause mold
252
Exposed wood cabinet should be how high above heat sources
30 inches
253
Smoke alarms should be kept how far away from cooktops
12 feet
254
What do GFCI’s detect
Current leaks and short to ground
255
What is likely when a bath fan draws well but mould persists along ceiling
Duct ends in un heated attic
256
What should be done with bath fan ducts
Should extend through the roof to outside air and be insulated
257
What should shower doors have on their stamp
It should say tempered or safety glass
258
What are lavatories
Bathroom sinks
259
Why should a faucet spout not terminate below a filled sink
Because waste water in the sink could siphon into drinking water
260
What should water supply lines have
Metal sheath burst proof flexible connecters
261
What is the likely cause of the sink that gurgles and smells like sewage
Flushing toilet sucks water from the sink due to faulty venting
262
Are corrugated drain approved for lavatories
Hell to the fuck nah
263
If water drips from a toilet in warm weather what is installed
A sweat stopper inside the tank
264
Is vinyl exhaust approved for driers
Nah son
265
When rocking a toilet, if it moves a lot and smells, what is the problem
Nuts are loose and wax ring failed
266
Why do some older driers not have a ground
The neutral served as equipment ground
267
Dryer receptacle wiring
4 pole 4 wire
268
Gas piping must be supported every
6 feet
269
What kind of Piping is approved for venting in addicts or crawlspaces
Smooth wall metal piping
270
What should be used to connect driers to wall
Flexible vent pipes
271
What should washers on top of wood have
A catch pan that runs to the drain pipe
272
Washer drain pipes should have what kind of trap
A P-trap. Never an S trap
273
Washer drains should have a trap where
Above floor level
274
Is a staircase landing required if the door swings away
Nope
275
Where are CO detectors required in regards to bedrooms
Within 10 feet of each bedroom
276
Are inspectors allowed to turn gas and pilot lights on
No
277
What is asbestos
A fibrous rock that is resistant to heat and chemicals
278
Describe radon
 produced by the decay of uranium and radium
Levels fluctuate the weather
Fans cannot be in the living areas
279
Can unvented heaters be the sole source of heat
No
280
What do you use to measure humidity what ranges are good
Around 40% is good. 60% and up is not good
281
How should you check for vapour barriers
Take receptacle covers off on exterior
282
How much more resistance than to airflow than straight pipe does flex duct have
Twice
283
What is static pressure
Measurement of airflow resistance
284
When HRVs are interconnected with forced air heating/cooling systems how should testing be done
Coordinated together
285
How does heat move
Hot air rises. Heat travels from hot to cold
286
If you have AC do you want a vapour barrier inside or outside
You don’t want a vapour barrier Inside
287
What is entropy (thermal dynamics)
Heat tried to even out. Depends on the speed of heat flow
288
The three mechanisms for heat transfer
Radiation, conduction, convection
289
Describe radiation heat transfer
The first way heat is transferred (ie body heat)
Differs from convection in that it can occur with a vacuum
290
Describe conduction heat transfer
When two bodies come into physical contact. (Thermal bridging)
291
Describe convection heat transfer
Transfer of heat between objects that are not touching. (By means of a fluid such as water or air)
292
Movement of convection heat transfer is called
Convective current
293
When does an insulator lose value
When it becomes wet
294
Addicts in the US we should be what R rating
R38 minimum
295
How do bulk insulators block conductor of heat transfer
By creating a space
296
How do bulk insulators block convective heat transfer
By holding air still
297
Why does air make a good insulator
Because air has low density
298
Air has a high resistance to what type of heat transfer is the lower resistance to what
High resistance to heat conduction
A little resistance to radiation and convection
299
When conduction convection and radiation occur at the same time, when does thermal resistance of air space become independent of gap width
When it is greater than 1”
300
What is often used in reducing downward heat flow
Reflective radiant barrier’s
301
Upward heat flow tends to be what type of heat transfer
Convection
302
What is the stack effect
Convective heat flow
When outdoor temperature is colder than inside, hot air rises to press through openings in upper floors
303
Water runs off of Rock wool. What is this called
Hydrophobic
304
What three things do you look for on windows
U factor
Solar heat gain coefficient
Air leakage
305
What is the U factor of a window
How will it performs in the winter. The lower the better. Heat loss
306
What is solar heat gain coefficient
Percentage of the heat from the sun that gets through
307
Low E glass reflects what kind of infrared waves and what doesn’t transmit
It reflects long wave infrared. Transmits light and short wave infrared
308
What are the thermal performance factors
Framing factor (25%)
Thermal bridging at frame/studs
 Wind washing
Gaps in insulation
309
What is the framing factor of the wall R value and frame and studs called
opaque wall
310
Some radiant barrier’s will preferentially reduce the flow of infrared radiation in comparison to other wave lengths. What is this called
Spectrally selective
311
Describe R-value
Ratio of the temperature difference across an insulator and the heat flux. (Heat transferred per unit area per unit time)
312
What is thermal bridging
A good insulator with a good conductor. Heat transfers from the conductor
313
What is a thermal break
Thermal bridge is broken into separate pieces with insulation
314
What is framing factor
Wall, floor, framing reduces R-value
315
If you have the same amount of insulation but it is not evenly distributed, what happens
Reduce R-value
316
Is drywall a good air barrier or vapour barrier
Good air barrier, not vapor. Some paints are good vapour barriers
317
What are the three methods of air infiltration into buildings
Wind pressure, stack pressure, mechanical pressure
318
Why is direct venting better than flues
Stack affect can happen
319
Should return air ducks be in the same cavity As combustion flus
No sir
320
How many safety stops to an automated garage door have
Two
321
What does the E in the low Ewindow systems mean
Emissivity
322
What are the purposes of an energy recovery ventilator
Recovers heat and moisture from exhaust
323
On a frosty day what do long narrow frost lines running up the roof indicate
The effect of the trust cords or rafters which are slightly insulating
324
Do standards expect you to inspect every window
No. Just a representative sample
325
Is a check valve on the floor drain an indication of water penetration into basements
No
326
What are common problems with exterior trim
, deteriorated caulking, paint or stain needed
327
What is emissivity in low E window systems
Reflect heat. Improves thermal performance
328
Sequence of gas furnace
Call for heat, since the pilot, turn on gas, sense, temperature of air at heat exchanger, turn on the blower, thermostat satisfied, turn off the gas, since the temperature in that heat exchanger, turn off the blower
329
What is a barometric damper?
Admits dilution air into the exhaust gases to aid in the draft
330
What does a thermocouple do you?
Senses, pilot flame
331
Heat exchangers do this
Separate combustion air from house air
