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Chapter 13
Exterior Wall Finish
Cornice
Definition: the overhang of a roof at the eave.Includes the fascia board, a soffit, and any moldings.Provides a finished connection between wall and roof.
Rake
Definition: Part of a roof that overhangs a gable.Projecting roof boards support trim for boxed rake section.Roof framing is extended when the rake projects a considerable distance.
Framing a Cornice
1. Install ledger strip along wall2. Mark points with level that match up
with bottem edges of rafters3. Nail on the ledger strip4. Cut the lookouts5. Toenail one end of the lookout to the
ledger and nail the other end to the overhang of the rafter
6. Apply the soffit
Prefabricated Cornice Materials
Various systems available
Ex. 3/8” laminated wood-fiber panels
Fasten with 4d rust-resistant nails spaced about 6” along edges and intermediate supports
Nail main supports first and then along edges
Always leave space for expansion
Metal Soffit Material
Provided in rolls and sheets in several widths Aluminum systems are suggested Widths vary from 12 – 48” Edges are held in runner guides that are attached to fascia and walls Consists of 3 basic units:
1. Wall hanger strips (frieze strips)2. Soffit panels3. Fascia covers
Hanging Metal Soffit
1. Snap a chalk line along the side wall, level with the bottom edge of the fascia board
2. Attach metal U-shaped wall hanger strip along line
3. Attach hanger strip flush with the bottom fascia or nail the metal soffit panels to the bottom of the fascia board as panels are installed
4. Insert the panels5. Cut metal or vinyl fascia cover to fit and
install it
Soffit (Cont.)
Horizontal wood siding
One of the most common materials Usually applied over a base of sheathing and a house wrap Bevel siding is most common
Available in various widths
Made by sawing plain surface boards at an angle
Wood Siding (Cont.)
Channel Rustic siding has shiplap type joints
Drop siding usually has tongue-and-groove joints heavier, has more structural strength
Wall Sheathing and Flashing
Siding can be applied over various sheathing materials. Solid wood, plywood, or nail-base fiberboard is nailed directly to the material at about 24” intervals. Gypsum board and regular fiberboard sheathing cannot be used as a nail base and the siding should be nailed through the sheathing and into the frame.
Sheathing Substitutes
An insulation board of rigid polystyrene (13-17) can take the place of sheathing and sheathing paper Metal flashings must be applied
(13-18)
Installing Horizontal Siding(Preparing a Story Pole)
1. Lay out the distance from soffit to 1” below top of foundation.
2. Divide distance into spaces equal to the width of the siding minus the lap.
3. Adjust the lap allowance so spaces are equal.
4. Mark position of top of each siding board on the story pole when layout is complete.
Installing Horizontal Siding(Continued)
1. Start application of bevel siding by first nailing a strip along the foundation line equal to the thin edge of the siding.
2. Apply the first piece.3. Allow the butt edge to extend below the strip to form
a drip edge.4. Inside corners can be formed with a square length of
wood or metal corners. Outer corners are usually made of metal. Install.
5. After the corner boards are in place, fit the siding tightly against them.
6. Wood siding can be given a coat of water-repellent preservative before it is installed, or it can be brushed on after installation
Nailing
To fasten siding, noncorrosive nails are recommended. Horizontal siding should be face-nailed to each stud. For narrow siding, the nail is generally placed about ½” above the butt edge. Different types of wood siding require different nailing patterns. (Fig. 13-26)
Estimating Siding
Increase the footage to make up for the difference between nominal and finished sizes. The net square footage of the wall surface to be covered should be multiplied by the factor in the chart to your left.
Vertical Siding
Commonly used to set off entrances or gable ends. Also for main wall areas. May be plain-surfaced matched boards, pattern matched boards, or square-edge boards covered at the joint with a batten strip. Made from solid lumber, should be no more than 8” wide.
Wood Shingles
Sometimes used for wall covering, and a large selection of types is available. Very durable and can be applied in various ways to provide a variety of architectural effects. Most shingles are made in random widths Shingles in side walls are frequently laid in double coursing
Double coursing- when you use a lower grade shingle under the shingle exposed to the weather. The exposed single butt extends about ½” below the butt of the under course.
Single Coursing of Side Walls
Similar to roof application—difference is in the exposures employed. Present less weather-resistance problems than roofs. Weather exposure of shingles should never be greater than half the length of the shingle, minus ½”. Should have concealed nailing.
Shingle and Shake Panels
Shingles and shakes for side wall application are available in panel form. Usually western red cedar. Standard size = 8’ Applied by following the same basic precaution and procedures described for regular shingles. However, takes less time.
Plywood Siding
Uses Provides a vertical
treatment to gable ends. Provides emphasis as
fill-in panels above and below windows.
Establish a continuous decorative band at various levels along an entire wall.
Must be made from exterior type plywood.
Most common- Douglas fir
Panel sizes are 48” wide by 8’,9’,10’ longBecause large sheets of plywood and hardboard siding provide tight, draft-free wall construction, it is important to have an effective vapor barrier. This should be between the insulation and the warm surface of the wall.
Joint details for plywood siding:
Aluminum Siding
Factory finished with baked on enamel and provides appearance that resembles wood siding Offers low maintenance costs For use on new or existing construction Can be applied over structurally sound surfaces
Vinyl Siding
Definition: a rigid polyvinyl chloride compound that is tough and durableInstalled with a backing or insulation boardPanels have interlocking joints that are waterproofNo movement during expansion or contraction
Installing Vinyl Siding and Soffits(Preparing the old siding)
Nail loose boards & trim-replace rotted boards Remove old caulk from windows and doors Remove downspouts, lighting fixtures and moldings that interfere with new siding Tie back shrubs and trees that can be damaged
Installing Vinyl Siding and Soffits(Continued)
Allow a ¼” expansion gap where siding meets accessories when cutting Do not drive nails tight against the siding, leave a gap of about 1/8” See fig. 13-61 for Installing Starter Strips and Trim
Installing Siding Panels
The first siding panel snaps into the bottom of the starter strip. Work toward the front of the building, finishing each side before starting the next Always cover largest areas first; smaller panels can be used up on the smaller surfaces, such as dormers Overlap each panel 1”, face butt edge away from the main traffic areas.
Stucco
Base consists of wood sheathing, sheathing paper, and metal lathApply second coat when first is dry to give a smoother “pebbled” finishTypically, the finished stucco wall is 7/8” thick
Exterior Insulation Finish Systems
Definition: also called “synthetic stucco” and are similar in appearance to stucco. Available either as polymer-based (soft-coat systems, typically 1/8” thin) or polymer-modified (hard-coat systems, about ¼” and are mechanically attached.)
Installation: Can be installed over wood,
concrete, concrete block, and other substrates.
Base coat should be at least 3/16” thick, apply two layers
Mesh is installed with laps offset from edges of openings, joint, grooves, and corners.
If base coat is required before applying the finish coat, it should e applied in 2 thin layers (1/16” each)
Brick or Stone Veneer
Veneer Wall- masonry wall, a wall framed in wood or metal to which stone, brick, or even concrete bock—are attached rather than siding
Tools
Trowel is the most used tool in the mason’s tool kit.
Toe (or point) – pointed end of the trowel
Heel – the wide end of the trowel
Mason’s level is also an important tool.
Has both vertical and horizontal vials, read from either side.
Aluminum or wood with metal edges.
Two rules, 6’ folding with a 6” sliding scale the other a 10’ steel tapeJointers or jointing tools are used to compressA brick hammer is used to drive nails, strike chisels, and break or chip masonry units
Masonry Materials
Bricks are structural units made to several sizes from clay or shale.
Material mixed with water then dried in large kilns
Building or Common Brick A strong general purpose
brick intended for use where strength is more important than appearance
Three grades: SW grade resists
freezing MW grade is used
where there may be exposure to below freezing temp. but in dry locations
NW grade is used to back up interior masonry
Masonry Materials (Continued)
Facing – used where appearance is important Three types:
FBX is for general use in exposed interior or exterior walls or partitions. Color and size are uniform
FBS is for general use in exposed exterior and interior walls and partitions where wider color variations and sizes are permitted
FBA is used to produce architectural effects produced by lack of uniformity in size, color, and texture
Mortar is mostly portland cement with the addition of hydrated lime and sand.
Designed to bond bricks and block into a strong, waterproof wall.
Blinds and Shutters
Installed at sides of window unitsConsist of frame assemblies with solid panes or louvers Used to protect the glass, provide security when locked. Serves decorative purpose nowAttached to exterior wall with screws or other fasteners