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Construction Documents and Detailing > Foundations and Footings > Flashcards

Foundations and Footings Flashcards

1
Q

Foundations

A

part of structure that interacts with the earth and supports the entire building

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2
Q

Cutting and Filling

A

Soils have multiple properties that when loads are placed upon them, they react differently

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3
Q

concrete is a mixture of:

A

Portland cement- 7% to 15% in Vol.
water- 14% to 21% by Vol.
aggregates- 60% -75% (gravel/ coarse or sand/fine)
admixtures - speeds hydration to get design strengthen faster, for color, air enhancement(creation of air bubbles which improves insulation and reduces weight)

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4
Q

Portland cement is composed of:

A 
lime
iron
shells
slag
shale
silica sand
alumina
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5
Q

Portland cement is used for?

A

mortar, grout, stucco, concrete

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6
Q

1 pound of cement contains 150 billion grains that forms a paste when mixed with water. This reaction is called?

A

Hydration

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7
Q

How many days after is full strength attained?

A

28 days

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8
Q

Types of Portland cement:

A

Type 10(GU,GUL)- general purpose cement - most commonly used
MS- Moderate sulfate resistance- used for concrete in contact with soil where there is little sulfate present
MH,MHL- Moderate Heat-
HE,HEL- High early strength, longer term strength- most commonly used in pre cast
LH,LHL- Low heat - not common today, used in dams, stronger after 24 months
HS- High sulfate resistance- concrete in contact with soil or groundwater, higher sulfate content, more common in canada and western us

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9
Q

What is the purpose of water?

A

to produce the chemical reaction with cement, must be free of any impurities, 1/3 is required for the chemical reaction

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10
Q

Shrinkage cracks and how to reduce it

A

result of excess water evaporating while the concrete dries.

add control joints

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11
Q

Types of aggregates:

A

Structural lightweight- shale, slate, clay, slag
Insulating lightweight- perlite, vermiculite, pumice, and scoria
Heavyweight- ferrophosphorus, barite, goethite, hematite, steel shot

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12
Q

Strip Footings

A

used under foundation walls, 2 to 3 times wider than the foundation wall, they transmit the loads of the structure to the soil.

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13
Q

Formsworks

A

are put on the side of the footing before pouring the concrete and is removed after the concrete has set
to maintain the size and shape

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14
Q

8” deep and 2’-6” or 3’-0” square and is used to provide support for columns

A

Pad footing

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15
Q

footings that go around the perimeter

A

Strip footings

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16
Q

Softwood lumber - always used for framing in Alberta
comes from coniferous trees
SPF stands for?
Hardwood - comes from deciduous treed and is used for more finish work

A

Spruces, pines, firs

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17
Q

Lumber is graded from four things:

A

Species- SPF
Structural properties- strength
Moisture content- s-dry(moisture content less than 19%
s grn- (moisture exceeds 19%)
Lumber used for grading-(structural construction) - must
have moisture content less than 19%

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18
Q

N.L.G.A Lumber grading mark 5 things

A 
certifying agency
mill number(00)
Species- SPF
Moisture content( kiln dried or heat treated)
Grade(No. 1)
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19
Q 
Nominal sizes:           Actual sizes?
2x2
2x4
2x6
2x8
2x10
2x12
A 
1 1/2" x 1 1/2"
1 1/2"x 3 1/2"
1 1/2"x 5 1/2"
1 1/2" x 7 1/4"
1 1/2" x 9 1/4"
1 1/2" x 11 1/4"
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20
Q

Pressure treated lumber is used on top of the? if it comes in contact with the?

A

concrete

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21
Q

a piece of wood that sits on top of the concrete foundation wall used to attach the floor joists to

A

sill plate

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22
Q
  1. used in residential construction - are usually wood that is laminated or build up
  2. typically steel and are adjustable
A

Colums

Beams

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23
Q

used for residential floor framing, can be dimensional lumber or engineered joists(I- joists)
spans btw your beams and foundation walls to support the floor

A

Wood Joists

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24
Q

are structural - can be used for large spans(commonly for floor framing
lightweight
dimensionally stable

A

Engineered wood joists

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25
Q

Floor opening framing, what happens to the joists?

A

joists are doubled up around the opening

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26
Q

is laid on top of the joists to finish off the floor framing?
5/8” t&g is more commonly used
comes in 4’x8’ sheets
joints are laid to align over joists
is laid perpendicular to the floor joists

A

Plywood Subfloor

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27
Q

What is required between joists to help distribute load from one joist to the next and prevent twisting and warping?
What are the three types:

A

Bracing and Bridging

Solid blocking, x type bridging, metal bridging

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28
Q

runs perpendicular to the joists ad can be : dimensional lumber, i-joists,LVL(laminated veneer lumber)

A

Header

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29
Q

functions of wall framing?

A

distribute load from the roof to floor above to below

resist wind forces

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30
Q

continous walls from foundation to roof
not common method anymore,
advantages- easier to insulate where the floor meets the wall
disadvantage- requires fire stop between floors

A

Balloon framing

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31
Q

walls rest on top of each floor and go up to the underside f the next floor,
common framing method today
Advantage- easier to construct, suport is solid, more stable, shorter straighter less expensive lumber
disadvantage- difficult to insulate where the floor meets the wall

A

Platform framing

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32
Q

Wall framing components:10 0bjects

A 
top
bottom plates
sill plate
jack stud
king stud
cripple stud
lintels 
headers
sheating
stud
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33
Q

vertical members of the wall (now 2x6s used to be 2x4s(fit more insulation and stronger? What are they spaced between every how many inches?
nailed to the jack stud?
under the lintel or header(above an opening) and supports it?
short studs that continue the the studs above or below an opening?

A

studs, 16” or 24”
king stud
jack stud
cripple studs

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34
Q

Walls are built no longer than? long lumber is expensive

A

16 feet

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35
Q

are typically doubled, transfer loads from above

the second top plate never has joints or splices

A

top plates

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36
Q

typically single
transfer load onto the rim or header joist in the floor
horizontal structure above an opening

A

bottom plates

lintel

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37
Q

lintel is made by nailing together what?

A

2 or 3 pieces of lumber side by side
2-2x10 or 3-2x9 lintel(2 ply 2x10 lintel)
it has rigid insul in the middle

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38
Q

lumber goes up only from?

A

8ft to 16ft

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39
Q

typical height of wall is actually? because of the additional top and bottom plates

A

8’-1 1/8”

40
Q

Rough opening of a window is actually:

A

37” x 49”

41
Q

framing is called ?

A

rough carpentry

42
Q

applied to the outside of the wall studs, to the top of floor joists and to the top of the roof trusses?
for subfloor thickness: 3/4
for walls and roof: 1/2

A

Sheating

43
Q

most common plywood for house construction?

common sheating product for houses ?

A

Veneer core plywood

OSB

44
Q

installed as 8’ - 0” and the edges are perpendicular to the floor joists

A

T&G subfloor

45
Q

Roof pitch or slope?

ratio?

A

rise over run.

3/12,4/12,12/12,5/12

46
Q

What type of slope or roof?
3/12
1/4”/12”

A

low slope roof

flat roof

47
Q

individuals boards are cut and nailed to form the top of the roof
rarely used nowadays
disadvantages: requieres more lumber, needs a skilled carpenter, requires multipled bearing points
advantages: can create more space in attic, can be faster for smaller projects

A

Stick framing

48
Q

most common framing method today
small boards are cut and connected using gang nail plates to create the roof and ceiling structure.
advantages: designed by engineers, quicker to install, use less lumber, can span distance up to 40 ft
disadvantage : can be expensive to transport, need to be ordered early

A

Roof trusses

49
Q

Parts of roof truss

A 
top chord
ottom chord 
truss webb
truss plate
overhang 
heel
50
Q

Ridge – the intersection at a peak of opposing roof planes
Soffit – the underside of the roof overhang
Fascia – the edge of the roof (rough fascia and finished fascia)
Eave – the roof overhang assembly (components include the edge of the roof, the fascia, and the soffit)
Valley – the intersection at the base of opposing roof planes
Dormer – a window or protrusion through a roof, an independent roof that is a part of the roof assembly

A
51
Q

applied in rows starting at the bottom of the roof
Advantages: Light, Easy to install, Variety of colors and designs.
Disadvantages: Can be peeled off in high winds Only last about 15 - 20 years

A

Asphalt Shingles

52
Q

Made from cedar, redwood, southern pine - most common and durable is cedar
installed over 1x6 strapping
Advantages: Light, Distinct look, Can last up to 50 years.
Disadvantages: must be on roofs with a minimum slope of 4/12, expensive, harder to install

A

Wood Shakes

53
Q

Made from real slate (rock)
Split to thickness and trimmed to size
Advantages: Fire resistant, Warrantied to last at least 75 years.
Disadvantages: heavy, roof structure must be built stronger
expensive, harder to install

A

Slate Shingles

54
Q

Portland cement and fibrous materials combined
Advantages: Fire resistant, Last at least 50 years.
Disadvantages: heavy, roof structure must be built stronger
expensive, harder to install

A

Cement Fiber Shingles

55
Q

Units overlap and interlock
Advantages: Fire resistant, variety of colors and profiles, Last at least 50 years.
Disadvantages: heavy, roof structure must be built stronger, expensive, harder to install, roof slope must be at least 4/12

A

Clay or Concrete Tiles

56
Q

Advantages : fire resistant, variety of colors and profiles, last longer than asphalt shingles,
Disadvantages - a bit more expensive, can be dented in hail storms

A

Metal Roof:

57
Q

Advantages: more flexible than most other roofing products, relatively inexpensive, lightweight, can be manufactured from recycled tires

A

Rubber Roofing

58
Q

expensive, integrated solar panels into shingles - to try to offset the cost of solar panel, still relatively new

A

Photovoltaic Panels:

59
Q

What is the building envelope?

A

The building envelope is the exterior perimeter of a building and is made of materials to keep the outside out and the inside in:

60
Q

Why Insulate?

A

Not only does it help to keep a building warm in the winter, but it also helps to keep it cool in the summer

61
Q

Where is the insulation in a building?

A

We can add insulation in the empty spaces within a wall, between the studs

62
Q

All materials have a thermal resistance value, which is a measure of how hard it is for heat to go through it.

A

R-Value of Insulation:

63
Q

The imperial unit for this resistance value is called R:
Typical R value for the insulation in a 2x4 wall is R12, and for a 2x6 wall the R value is R19
The metric unit for thermal resistance is called RSI:
R12 is equal to RSI of 2.11, and R19 is the same as RSI 3.35
The conversion factor is: 1 RSI = 5.67826 R

A
64
Q

Insulation Types

A 
Batt
Loose Fill
Rigid or Boards
Semi-Rigid
Foamed in Place or Spray Foam
65
Q

Batt insulation is packaged into bags of individually cut batts of insulation.
For a 2x6 wall with studs spaced 16” O.C., a batt is: 5 1/2” thick by 15” wide by 47” tall:

A
66
Q
  • Batt insulation is made with thin strands of glass or glass fibres randomly orientated in layers making an individual batt
  • Wearing a dust mask is a must when working with batt insulation, the fibres are tiny like dust and can easily be breathed in
  • Glass is not a good insulator, but all the trapped air between the strands of glass is. Air is a good insulator.
  • Batt insulation should not be compressed, cut a piece just slightly larger than the space it is to fill
A
67
Q

Loose Fill Insulation or Blown-in Insulation
• not to be confused with spray foam insulation
• loose dry bits of insulation are sucked up by a truck vacuum and air blown into an attic (or walls)
• common loose fill insulation materials are fiberglass or cellulose (shredded paper, shown in image above)
• can settle over time which causes a slight loss in R value
• easy to apply and fill awkward spaces (like attics)

A
68
Q

Rigid or board Insulation:
• is sold in rectangular boards, typically: 2’-0” x 8’-0” but are sold in other sizes too
• have a better R value per inch than batt insulation, loose fill, or semi-rigid insulation
• comes in different types - some are good for below grade installation, and some are not
• expanded:
• polystyrene - think of the white Styrofoam coffee cups
• open cell - pockets are connected
• R1.2 - 2.5 per inch thickness
• extruded:
• higher R values (R2.5 - 5.1 per inch thickness)
• closed cells - pockets not connected

A
69
Q

• again, it isn’t the material that is the main insulator it is all the tiny air pockets

A
70
Q

Semi-Rigid Insulation:
• like batt insulation in that they are precut to rectangular pieces designed to fit between studs (batts)
• more dense / stiffer and better R value than fibreglass batt insulation
• common brand is ROXUL which has now changed it’s name to Rockwool
• rock based mineral fibre - Basalt rock and recycled Slag (instead of glass based)
• it has a better fire resistance rating than the other types of insulation
• is also resistant to mold growth and rot
• does not irritate the skin like fibreglass batt insulation
• easy to cut

A
71
Q

Spray Foam or Foamed in Place Insulation:
• very good R value per inch, like Rigid insulation
• can fill awkward spaces; it expands and hardens to fill and seal tightly
• if there is structural movement, this insulation will not flex - gaps will appear
• some act as a vapour barrier too (closed cell)
• must wear protective equipment when spraying
• building should be left to vent or air out for several hours after spraying
• spray foam must be covered with a fire retarding barrier after it has hardened
• covering with wall or ceiling gypsum board achieves this barrier
• spray foam releases toxic fumes when it burns
• very expensive - so usually used in smaller harder to insulate areas (rim and header joist areas, for example)
• some studies have found that spray foam loses some R-value when it gets cold

A
72
Q

Vapour barriers are needed to prevent air movement between the inside and the outside:
• a vapour barrier is anything that prevents the movement of water vapour through it:
• typically, these also prevent the movement of air through them
• usually 6mil Polyethylene (plastic roll sheeting) is used
• 6mil is an Imperial measurement meaning 6 thousandths of an inch thick (0.006”)
• we cannot allow the warm moist air in a building to move through the wall
• if we did, in winter the moisture within this air would condense to liquid water within the wall, causing rot and mold
• just like insulation, vapour barriers must be continuous:
• the below image shows the poly on the inside of the exterior walls and connected to the poly on the ceiling
• the poly here stops and is sealed to the top of the subfloor, it will start up again below the subfloor

A
73
Q

• vapour barriers are ALWAYS on the warm side of the insulation
• warm side meaning toward the heated part of the building
• heated space is also called conditioned space, because we are trying to maintain a condition (temperature, humidity, air movement) in that space
• vapour can move two ways through a wall:
• diffusion: moisture wants to move to where there is less moisture to try to balance or equalize the moisture content
• air transport: air leakage or air movement. There is usually different air pressure inside a building vs outside, which can cause air to want to move through the envelope of a building.
The closed cell type does not require a vapour barrier.
Insulation is great, but without a vapour barrier, we would be worse off than if we had no insulation at all!

A
74
Q

A “Frost Wall” is….
• an insulated wall framed on the inside of a foundation wall
• this is to continue the insulation from the walls and floor above, down below the ground level outside
• a bit of space is left between the frost wall and the foundation wall…
• so, the moisture in the concrete wall does not get the insulation in the frost wall wet
• to provide a straight and level wall for the basement
• it is called a “frost wall” because it needs to be insulated from the underside of the floor to below the “frost line” outside
• What is a “Frost Line”?
• each geographical location has a different frost line depth
• Whitehorse will have a deeper frost line than Edmonton
• Edmonton’s frost line is about 4’-0” deep
• this means the ground is expected to freeze to a depth of 4’-0” throughout the course of the winter
• this can vary and most builders assume a deeper frost line or depth
• foundations must be at least to this depth and so does the insulation in the basement frost walls

A
75
Q

What is the purpose of a Frost Wall?

A

To continue the insulation of the house down below the grade level outside.

76
Q

Gypsum board:
• the system of using gypsum board, tape and mud (joint compound) forms a smooth interior wall surface called drywall
• gypsum board is a core of gypsum sandwiched between two thin coverings
• gypsum is a soft sulfate mineral composed of calcium sulfate dihydrate (CaSO₄·2H₂O)
• main ingredient in sidewalk chalk and plaster
• is fire resistant
• particles smaller than smoke
• there are many different types of gypsum boards - different thicknesses and coverings
• some are more “moisture resistant” and some are more “fire resistant”
• the most common thickness for residential buildings is 1/2”
• the typical covering is a smooth white paper on the front face and a basic brown paper on the back side
• these boards come in a variety of sizes: 4’x8’, 4’x9’, 4’x10’, 4’x12’ and also 54”x8’, 54”x10’, 54”x12’
• the larger the sheets the fewer the seams and the smoother the wall finish
• gypsum boards usually are nailed along the perimeter and screwed in the “field” or in the middle
• drywall mud is:
o a creamy mixture of water, limestone, expanded perlite, ethylene-vinyl acetate polymer, attapulgite, and other ingredients
o gets spread on the joints and nail / screw heads of the gypsum boards (spreads like thick toothpaste)
o hardens and is sanded smooth (usually 3 layers are applied to achieve a smooth seam)

A
  • gypsum board used on the ceilings usually needs to be a bit stronger, because:
  • roof trusses usually are spaced further apart than wall studs, typically at 24” O.C.
  • they need to support the weight of the insulation
  • they are horizontal - gravity is working against them
  • the edges of gypsum boards are a bit thinner (tapered) to allow for tape and mud to cover the seams between boards (see images)
77
Q

Tyvek is a very common house wrap brand, what is a house wrap for?
they act like a Gore-tex jacket for a building:
• they allow air through, but very slowly (hence the name air retarder)
• they do NOT allow liquid water through, but they do allow water vapour through (smaller molecules than liquid water)
• available in long 9’-0” wide rolls; the seams are taped together to continue the seal
• a building’s walls need to breath:
• if moisture gets into the wall, it needs to be able to dry out
• most of the moist air from inside the house should be blocked by the vapour barrier, but nothing is perfect
• there are two purposes for a house wrap:
• to drastically slow air movement through a house wall:
• which is what the vapour barrier does as well
• this prevents heat and moisture loss through air movement between inside and outside
• but to still allow water vapour to move through
• to be a secondary or backup liquid water (rain) barrier (a primary water barrier would be siding, for example)

A
78
Q

There are other types of house wraps:

A

Black building paper (image above):
• Kraft paper saturated with asphalt
• very common until 1970-80s
• a bit better as an air barrier than Tyvek
• tears more easily than Tyvek
Self Adhered Membranes:
• Torch on or self-adhesive SBS Modified Bitumen Membranes.
• Self-sealing seams
• Very thick and strong
• Flexible
• The Cadillac of air retarders – commonly referred to as an “Air-Seal Membrane”
Liquid Applied Membranes:
• Rubberized coatings, quickly gaining popularity
• Soprema calls for them in their roofing designs
• EIFS (Stucco - Exterior Insulated Finish System) installers use them
• Applied by roller or spray – less effective at joints (difficulty spa

79
Q

Exterior Finishes: Siding

A

Horizontal Vinyl Siding:
• vinyl is very a common siding material:
• advantages:
• reasonably durable
• resilient or flexible
• mostly maintenance-free
• easy to install
• variety of colors and textures available
• relatively inexpensive
• disadvantages:
• some people do not like the appearance
• sustainability concerns with the material (difficult to re-use or recycle; production takes energy)
• melts relatively easily (i.e. BBQ too close)
• not as durable as other siding (can be damaged by hail)
• expands and contracts with temperature changes
• start at the bottom of each wall one row at a time
• each row interlocks with the row below

HardieBoard Siding (image below):
•	lightweight concrete panel siding
advantages:
•	very durable
•	fire resistant
•	variety of colors and textures available
•	low maintenance
•	very little expansion or contraction
disadvantages:
•	expensive
•	harder to cut and install
•	start at the bottom of each wall one row at a time
•	each row is nailed to the wall overlapping the row below (no interlocking)

Cementitious Stucco:
“Cementitious” or “old fashioned” stucco (vs. the new acrylic based stucco - more on this in future courses)
a mixture of cement, lime, sand, and water, and may include a pigment for color
mixed on site and hand troweled on to the wall
usually about 1/2” to 3/4” thick
3 coats: scratch coat, brown coat and finish coat

 
Exterior Finishes: Parging
a thin coat of a cementitious or polymeric mortar applied to concrete
typically about 1/8” to 1/4” thick
provides a simple, inexpensive finish to concrete walls
troweled on to the wall in 2 coats: scratch and finish

80
Q

What is an Eave?

A
  • the eave is the whole construction / details of the roof at the low end - its how the roof starts
  • after the roof is framed and sheathed, the following materials are added in order:
  • the soffit is installed
  • the 2x2 backing is not required with modern aluminum soffits - they use “J” or “L” tracks here (see image of “J” track below)
  • then the finished fascia (called “fascia cover” in image above)
  • then the metal drip edge
  • now the roof is ready for membranes and shingles
81
Q

Aluminum Soffits:

A

it has holes or perforations in it to help vent the attic space (more on this in a bit)

82
Q

No Soffit:
a horizontal soffit is not required, as long as the attic insulation is blocked from falling out and there is venting to the attic at the eave

A
83
Q

Gable End Vents:

A

Ventilation is required at the eaves, like we have seen with the soffits, but is also required to be near the peak of attic spaces too.
vents in the wall near the peak of a gable end wall can be a part of this ventilation

84
Q

Roof Vents:

A

a standard roof vent is shown below - no moving parts
these are usually used near the peak of roofs, but they sometimes are used near the eave to help with the lower roof ventilation requirements as well

85
Q

Whirlybird Roof Vents:

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a whirlybird roof vent (shown below) is one that spins due to outside wind and from warm air leaving the attic through it
these have fan blades built into them, so when they turn they force more air to leave the attic
these may require maintenance to keep them moving - sometimes they can squeak when they rotate

86
Q

Attic Insulation Stops:
• the tape measure in the image above is pointing to the brown cardboard insulation stops
• these are installed prior to blowing insulation into the attic (as well as ceiling vapour barrier and gypsum boards)
• these prevent the blown in insulation from completely filling the heel height and soffit with insulation
• notice the stops form a vertical wall and a sloped wall just below the underside of the roof sheathing
• there needs to be a minimum of a 1” space between the insulation and the underside of the roof sheathing
• this allows air to move from the soffit vents (low vents) to the roof vents (high vents), venting the attic space

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87
Q

No Attic Insulation Stops:
• insulation stops are not required, but there still must be a 1” space between the insulation and the roof sheathing
• they are used when the attic insulation is the blown in type because they make it easy to maintain that gap
• if fibreglass batt insulation is used in the attic, the batts can be cut to maintain that gap, without the use of insulation stops
 

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88
Q

What Causes Ice Damming:
• the attic space is too warm in the winter
• this melts a thin layer of snow, immediately above the shingles, turning it into water
• this water slowly flows down the slope of the roof towards the eave
• the roof above the overhang is not heated so this part of the roof usually stays cold in the winter
• the water reaches the overhang and freezes, slowly forming a sheet of ice and icicles (image above)

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89
Q

Damage from Ice Damming:
• as this sheet of ice or ice dam forms it expands up the roof wedging itself between the shingles - shingles are not designed to prevent movement water up the roof slope
• now when the temperature outside is warm enough to start melting this ice dam, water flows under the shingles
• this can get into the attic and onto the ceiling drywall causing mold, rot and water damage

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90
Q

How to Prevent Ice Damming:
the best way to prevent ice damming is to keep the attic at the same temperature as the outside air, by…
• having proper insulation with no gaps right to the outside face of the wall framing
• having proper attic ventilation:
• with adequate soffit and roof venting - both low and high vents are required

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  • having at least 1” space above the attic insulation at the eaves
  • lots of attic insulation and no venting will still cause ice damming (no matter how good the insulation, heat will get through it)
  • sealing and insulating the attic hatch
  • this is why roofers install the ice and water shield over the lower portion of roofs - to help prevent water migration if there is an ice dam
  • after a snow fall, roofs should be evenly covered with snow, if part or all of the roof is bare shortly after the snow fall, there is a problem with the attic temperature
91
Q

Other Ways to Prevent Ice Damming
• shovel off the snow covering the lower portion of the roof
• install heat tracing wires to melt the snow and ice from the lower portion of the roof
• these are addressing the symptoms but not the problem!

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92
Q

Metal Flashings are Required at Changes in Roof Materials:
• flashings for a shingled roof usually work like a shingle - they fit over top of the lower course of shingles and fit under the course above
• step flashings are common; they are used when the roof meets a wall going up the roof - i.e. a dormer, chimney or side of a skylight (see image below for step flashing)
• there is usually some part of the flashing is visible when the roof is complete

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93
Q

Gutters or Eavestrough:
• the gutter is the horizontal trough that catches the water flowing off the roof
• a drip edge supports the ends of the shingles and ensures the water will drop into the gutter
• the gutter is sloped so the water in it flows to one end of the gutter
• at the end of the gutter or eavestrough there will be a hole cut in the bottom of it to allow the water to drain out of it

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94
Q

Downspouts:
a downspout is mounted to the hole in the eavestrough to funnel the water down to the ground
the end of the downspout should extend several feet away from the building near the ground
a large amount of water is drained from a roof during a rain storm, it is critical to get this water away from the building
the ground should be sloped away from the building to shed the water away
a downspout is required every so many feet of eavestrough (about every 30 - 40 feet)

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95
Q

No Gutters and Downspouts:
• without gutters and downspouts the water falling from the roof overhang to the ground will dig a trench
• this will likely flow towards the foundation wall causing water to enter the basement
• weeping tile around the perimeter of the house is not designed to handle water from the roof, just from heavy rains that hit the ground

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96
Q

Lookouts are usually 2x4 lumber spaced at 24” o.c. and rest on top of the gable truss or gable end wall, perpendicular to it.

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Construction Documents and Detailing (1 decks)

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