Week 10 Moisture Flashcards
_______ protects the roof sheathing from moisture until the roofing shingles are applied. Once the roofing is applied, the underlayment provides the sheathing with additional protection from ________.
Eave Flashing
Eave flashing is required whenever there is a possibility that ____ might form along the eave and cause melting ice and now to back up under the roof shingles.
Drip edges of corrosion resistant metal are applied ______ underlayment along rake, and directly to the roof deck along the eave.
Underlayment protects the roof sheathing from moisture until the roofing shingles are applied. Once the roofing is applied, the underlayment provides the sheathing with additional protection from wind-driven rain.
Eave Flashing
Eave flashing is required whenever there is a possibility that ice might form along the eave and cause melting ice and now to back up under the roof shingles.
Drip edges of corrosion resistant metal are applied over underlayment along rake, and directly to the roof deck along the eave.
On normal slope roofs, eave flashing consists of two layers of ____lb felt or a single layer of ____lb smooth roll roofing extending from the eave up the roof to a point 24” inside the interior wall .
On low slope roofs, an additional course of underlayment is placed and extended to a point ___” inside the interior wall line.
Normal slopes are ___:12 and up
Low slope roofs are ____:12 to ___:12
On normal slope roofs, eave flashing consists of two layers of 15lb felt or a single layer of 50lb smooth roll roofing extending from the eave up the roof to a point 24” inside the interior wall .
On low slope roofs, an additional course of underlayment is placed and extended to a point 36” inside the interior wall line.
Normal Slope 4:12 and up
Low slope roofs are 3:12 to 4:12
Wood Shingles
Wood shingles and shakes are normally cut from red cedar, although white cedar, redwood, and red cypress shingles may be available. ________ has a fine, even grain and is naturally resistant to water, rot, and sunlight.
What is the difference between wood shingles and woodshakes?
Wood shingles and shakes are normally cut from red cedar, although white cedar, redwood, and red cypress shingles may be available. ________ has a fine, even grain and is naturally resistant to water, rot, and sunlight.
Wood shingles are sawn. Wood shakes are formed by splitting a short long into a number of tapered radial section, resulting at least one texture face.
Use only _____ resistant nails, such as hot dipped galvanized steel or aluminum-ally nails. ____ fasteners per shingle are required.
Spaced 1x__ or 1x__ sheathing provides ______ for the shingles. Board spacing is equal to the single ______
26-gauge galvanized steel or 0.019” ______-resistant flashing: provide underlayment under flashing in _____ climates.
___” minimum to each side of valley centerline with ___” wide underlayment for roof slopes of ___:12 and over
In areas subject to wind-driven snow and roof ice buildup,______ over solid sheathing is required.
Use only corrosion resistant nails, such as hot dipped galvanized steel or aluminum-ally nails. Two fasteners per shingle are required.
Spaced 1x4 or 1x6 sheathing provides ventilation for the shingles. Board spacing is equal to the single exposure
26-gauge galvanized steel or 0.019” corrosion-resistant flashing: provide underlayment under flashing in severe climates.
1” minimum to each side of valley centerline with 36” wide underlayment for roof slopes of 3:12 and over
In areas subject to wind-driven snow and roof ice buildup, eave flashing over solid sheathing is required.
Composition Shingles
Composition shingles have either an ______ fiberglass base or an ______ felt base surfaced won the weather side with colored mineral or ceramic granules.
Most composition shingles have tabs with __________ or locking tabs that make them wind resistant . Wind resistance is important when shingles are used on low-lope roofs and in areas subject to high winds.
One square = 100sf
Most common asphaly shingle type?
Minimum recommended slope?
Composition shingles have either an inorganic fiberglass base or an organic felt base surfaced won the weather side with colored mineral or ceramic granules.
Most composition shingles have tabs with self -sealing adhesive or locking tabs that make them wind resistant . Wind resistance is important when shingles are used on low-lope roofs and in areas subject to high winds.
One square = 100sf
Three-tab square butt
4:12
What is slate?
What range can slate shingles weight per square of roof area?
Slate is an extremely durable, fire resistant, and low maintenance roofing material. Slate shingles are split, trimmed and drilling to receive copper nails or wire ties. The principles governing their application are similar to those of wood shingles.
800 to 3000lb. Heavier than normal roof framing or decking is therefore required.
Tile roofing
Tile roofing consists of clay or concrete units that overlap or interlock to create a strong textural pattern. Like slate, roofing tiles are fire resistant, durable, and require little maintenance. They are also heavy (800 to 1000lb per square) and require roof framing that is strong enough to carry the weight of the tiles. True or false?
True
Mission or Spanish tiles are tapered, semi-cylindrical roofing tiles laid convex side up to overlap flanking, similar tiles laid concave side up. True or false?
What is their minimum recommended slope?
True
4:12
Corrugated Metal Roofing
Corrugated or ribbed roofing panels span between roof ______ or _____ running across the slope. The roofing panels may be of:
Aluminum with a natural mill or enameled finish
Galvanize steel
Fiber glass or reinforced plastic
Corrugated Structural glass.
What is the minimum recommended slope?
Roofing panels may be factory-cut to the _______ of the roof from ridge to eave.
Purlin spacing=span of roofing: ____’-_____’ typical
Preformed closure strips ______ the openings of ribs or corrugations against wind driven rain and insects.
Corrugated or ribbed roofing panels span between roof beams or purlins running across the slope. The roofing panels may be of:
Aluminum with a natural mill or enameled finish
Galvanize steel
Fiber glass or reinforced plastic
Corrugated Structural glass.
3:12
Roofing panels may be factory-cut to the full length of the roof from ridge to eave.
Purlin spacing=span of roofing: 2’-6’ typical
Preformed closure strips seal the openings of ribs or corrugations against wind driven rain and insects.
Any insulation should be integrated within the _____ of the roof structure.
Mechanical fastenings are made through the ____ portion of the _______ or _______. Washers and gaskets are generally _______.
Any insulation should be integrated within the depth of the roof structure.
Mechanical fastenings are made through the top portion of the corrugation or ribs. Washers and gaskets are generally required.
Sheet metal roofing
A sheet metal roof is characterized by a strong visual pattern of interlocking seams and articulated ridges and roof edges. The metal sheets may be of copper, zinc, alloy, galvanized steel, or teme metal, a stainless steel plated with an alloy of tin and lead.
Horizontal and valley seams are ____ and usually ______
Vertical seams are spaced from ____” to _____”
What is the minimum slope?
A sheet metal roof is characterized by a strong visual pattern of interlocking seams and articulated ridges and roof edges. The metal sheets may be of copper, zinc, alloy, galvanized steel, or teme metal, a stainless steel plated with an alloy of tin and lead.
Horizontal and valley seams are flat and usually soldered
Vertical seams are spaced from 12” to 24”
3:12 may be less if locked and soldered seams are used.
The seams on prefabricated batten roofs are spaced from ___” to ___”
The seams on prefabricated batten roofs are spaced from 24” to 36”
______ seams are made by folding up the adjoining edges against each other, then folding their upper portion over in the same direction a number of times.
______ seams are made by turning up the adjoining edges against a batten and locking them in place with a metal strip placed over the batten.
______ seams are joints between two pieces of sheet metal in the direction of fall of a curved or sloping roof, made by turning up the adjoining edges against each other, then bonding them around to form a cylindrical roll.
______ seams are made by folding up the adjoining edges against each other, folding them over, and flattening the interlock.
Standing seams are made by folding up the adjoining edges against each other, then folding their upper portion over in the same direction a number of times.
Batten seams are made by turning up the adjoining edges against a batten and locking them in place with a metal strip placed over the batten.
Roll seams are joints between two pieces of sheet metal in the direction of fall of a curved or sloping roof, made by turning up the adjoining edges against each other, then bonding them around to form a cylindrical roll.
Lock seams are made by folding up the adjoining edges against each other, folding them over, and flattening the interlock.
Roof drainage
The amount of rain or melting snow a roof and its drainage system must handle is a function of:
1. The roof area leading to the roof drains or gutters
2. The frequency nd intensity of the rainfall for the region
Rainwater shed by sloping roofs should be caught by _____ along the eave to prevent ground erosion. ______ empty into ____ downspouts or leaders that in turn, discharge into a dry well or storm sewer system.
____ are typically of vinyl, galvanized steel, or aluminum, although copper, stainless steal, teme metal, and wood ones are also available. Aluminum ____ can be cold formed on site in continuous runs without joints.
Place _____ below the roof slope line so that snow or ice can ____ free.
Rainwater shed by sloping roofs should be caught by gutters along the eave to prevent ground erosion. Gutters empty into vertical downspouts or leaders that in turn, discharge into a dry well or storm sewer system.
Gutters are typically of vinyl, galvanized steel, or aluminum, although copper, stainless steal, teme metal, and wood ones are also available. Aluminum gutters can be cold formed on site in continuous runs without joints.
Place gutters below the roof slope line so that snow or ice can slide free.
FLASHING
Flashing refers to thin continuous pieces of sheet metal or other impervious material installed to prevent the passage of water into a structure from an angle or joint. Flashing generally operates on the principle that, for water to penetrate a joint, it must work itself upward against the force of gravity or, in the ace f wind-driven rain, it would have to follow a tortuous path during which the driving force would be dissipated.
Flashing may be _______ or ________. _______ flashing is usually of a sheet metal such as aluminum, copper, painted galvanized steel, stainless steel, zinc alloy, teme metal, or copper-clad lead.
Flashing _______ with a construction assembly may be of sheet metal or a waterproofing membrane such as bituminous fabric or plastic sheet material, depending on climate and structural requirements.
Flashing refers to thin continuous pieces of sheet metal or other impervious material installed to prevent the passage of water into a structure from an angle or joint. Flashing generally operates on the principle that, for water to penetrate a joint, it must work itself upward against the force of gravity or, in the ace f wind-driven rain, it would have to follow a tortuous path during which the driving force would be dissipated.
Flashing may be exposed or concealed. Exposed flashing is usually of a sheet metal such as aluminum, copper, painted galvanized steel, stainless steel, zinc alloy, teme metal, or copper-clad lead.
Flashing concealed with a construction assembly may be of sheet metal or a waterproofing membrane such as bituminous fabric or plastic sheet material, depending on climate and structural requirements.
