wood construction

Question 1

difference between softwood and hardwood

Answer 1

softwood - large vertical cells - small % of radical cells

hardwood - small vertical fibers -large % of radical cells

Question 2

considerations of sustainability in wood construction

Answer 2

• wood is the only major structural material that is renewable
• basic form of forest management
• — clearcutting and replanting (biodiversity ecology problem)
• — sustainable forestry (most recommended

Question 3

FSC-Certified

Answer 3

forest stewardship concil

Question 4

drying wood

Answer 4

klin - using large amount of fuel - high energy consumption - faster process

air - uses sunlight and wind - removing moisture at a slower pace

Question 5

construction process - site waste

Answer 5

• design with full standard sizes of lumber and wood panel materials
• prefabrication

Question 6

indoor ari quality (AQ)

Answer 6

• adhesive and binders cause serious VOCs such as formaldehyde
• some paints, varnishes, stains, and lacqers emit fumes unhealthful
• in damp locatioiins, mold and fungi may grow

Question 7

building life cycle

Answer 7

• fire: provide smoke alarms, sprinkler systems, and easy escape routes
• recycled with demolition

Question 8

seasoning

Answer 8

seasoning means when the wood is dried in order to reduce shrinking in the field

Question 9

grading lumber

Answer 9

2 types

• appearance - what is visible to the eye. visual test
• structural - visual and machine test

Question 10

wood chemical treatment

Answer 10

• fire-retardant treatment - elongates time before catching on fire - combustibility
• preservative-treated - decay and insects

Question 11

exterior wood products

Answer 11

• decay-resistant and moisture resistant wood planks
• fasterners much be hot-dip glavanized or stainless steel to avoid corrosion
• always have open spaces joints to allow for drainage of water and expansion

Question 12

wood fasteners

Answer 12

face nails - very strong
end nail - weakest fastener
toe nail - weak

Question 13

fire-resistive heavy timber construction

Answer 13

firecut beam so that when building catching on fire the whole thing doesn’t all fall at the same time, rather it is separate

-key in preserving old buildings

Question 14

difference between platform and balloon frames

Answer 14

plateform - new - continuous height studs - firestop - studs rest at each floor

balloon - old - by level studs - no fire stop - joists rest on ribbon

Question 15

walls - framing systems

Answer 15

• walls are frmaed with reptitive verticcal studs that are connected at the top and bottom by horizontal platese

Question 16

floors - framing systems

Answer 16

-floors are framed with repetitive joists that are connected at their ends by headers

Question 17

roofs - framing systems

Answer 17

-roofs are framed with rafters. every surface is sheathed with wood panels

Question 18

sitecast concrete or concrete block masonry

Answer 18

-typical details for a sitecast concrete foundation and basement for platform frames buildings

Question 19

firewall

Answer 19

firewall consists of light-guage mental framing, noncombustible insulation, and gypsum board
-common in commercial

Question 20

roofing underlayment

Answer 20

• aka building felt

- cellulose fibers with asphalt

Question 21

wall moisture barrier

Answer 21

-repel water and restrict the leakage of air (vapour retarder is placed on the warm side of thermal insulation

Question 22

ventilated roofs

Answer 22

-ice fams form because no insultation and no ventilation
optimizing snow melting; insulation, attic ventilation, vent spacers, and ice barrier
types of vents : soffit, gable, and ridge

climates like Canada

Question 23

unventilated roof

Answer 23

simplicity of detailing
no risk of windblown water entry
arixona climate

Question 24

drainage

Answer 24

• no fascia or gutter works best for steep roof with a sufficient overhand to drain water
• rule of thumb : wall is twice as tall as the depth of the overhang
• short downsprout problems : to close to foundation wall and cause soil erosion

Question 25

board siding

Answer 25

nailed over wall sheathing and house wrap

vertical wood spacers called furring strips

Question 26

shingle siding

Answer 26

sheathing must allow for drip
closing the open vertical jonts with the wall
each course covers the open joints in the course below

Question 27

masonry veneer - siding

Answer 27

brick or stone
metal ties prevent masonry from falling
weep holes allow for drainage of accumulated water in cavity

Question 28

insultating the buuilding frame - 6 types

High R-value = good insulation
low R-vlaue =bad insultation

Answer 28

1. batt or blanket - rock wool: low cost, fairly high r-value, easy to install
2. high-density batt - glass wool, low in cost, fairly high r-value, easy to install
3. loose-fill - rock wool, good for retrofit insulation in an older building
4. loose fibers with a binder- glass wool: low in cost, fairly high r value
5. foamed in place - polyurethane: high r-value, high cost, seal against air leakage, vapor impermeable
6. rigid board - high r-value, vapor permeable, moderate cost

Question 29

thermal bridging

Answer 29

occurs where solid framing members interrupt the thermal insulation layer, creating wall areas with lower thermal resistance than surrounding areas, reducing the insulation efficiency of the wall as a whole

thermal bridging = one big piece of wood

Question 30

thermal bridging alternative - 2 types

Answer 30

1. insulated space between header and members of a window

2. spacer provides full nailing around the opening