chapter 43 common commercial construction materials

Chapter 43

Common Commercial Construction Materials

Introduction• Most materials in commercial construction

can be used in residential construction– But are not because of cost and cost of labor

• Wood and lightweight steel are the exceptions

– Common materials include:• Wood

• Concrete block

• Poured concrete

• Steel

Wood• Platform construction

– Walls• Type IV and Type V commercial projects

– Roofs• Many small commercial projects

• Heavy timber construction– Structural framework of a building

• Size and location of beams and posts are specified on floor or framing plans

Wood (cont’d.)• Laminated beams

– Smaller members laminated together to form the larger beam

• Common material for buildings requiring large amounts of open space (e.g., gymnasiums)

• Common types: single span, Tudor arch, and three-hinged arch

– Beams can be represented using different methods

Concrete Block• Used to form the wall system for many types

of buildings– Durable and inexpensive to install and maintain– Sizes listed are width × height × length

• Typically manufactured in 8 × 8 ×16 modules

– Type, size, and reinforcement are specified on plan views

• Bold lines to represent edges of masonry

Concrete Block (cont’d.)• Steel reinforcement

– Reinforced masonry structures are stable • Masonry, steel, grout, and mortar bond

– Considerations:• Reinforcing bars• Steel placement• Rebar representation• Locating steel

Poured Concrete• Composed of sand and gravel bonded

together with cement and water– Most common is Portland cement

• Pulverized particles of limestone, cement rock, oyster shells, silica sand shale, iron ore, and gypsum

Poured Concrete (cont’d.)• Cast-in-place concrete

– Introduced as method of forming residential foundations and retaining walls

• Commercial application casting size and reinforcement varies

– Often used for walls, columns, and above-ground floors

– Poured using ribbed and waffle floor methods

Poured Concrete (cont’d.)• Precast concrete

– Consists of forming walls or components off-site and transporting to the job site

• Parts typically have an exposed metal flange• Many products are prestressed

• Tilt-up– Preformed wall panels are lifted into place

• Panels are formed at the job or off-site

Steel Construction• Lightweight steel framing

– Structural members include studs, joists, open-web trusses, space frames, and decking

• Space frames– Three-dimensional spatial grid that can be

used to span distances up to 80'

Steel Construction (cont’d.)• Prefabricated steel structures

– Structural system comprises a frame • Supports walls, roof, and externally applied loads

– Tapering members • Allows minimum material used

– Wall system• Made of horizontal girts attached to vertical frame

– Drawings • Show exact locations of members and connections

Steel Construction (cont’d.)• Steel-frame buildings

– Require engineering and shop drawings– Structural steel

• Identified as a plate, as a bar, or by its shape• Produced in the shapes

– Plans show location and size of each steel column, girder, beam, and joist

• Details show each intersection of structural members, and connection methods

Common Connection Methods• Nails

– Common connector for wood-to-wood members with a thickness of less than 1 1/2”

– Common types:• Common• Deformed• Box• Spikes

Common Connection Methods (cont’d.)

• Staples– Connect asphalt roofing and attaching

sheathing to roof, wall, and floor supports

• Power-driven studs– Anchor wood or metal to masonry

• Screws– Flathead, roundhead, lag screws

Common Connection Methods (cont’d.)

• Metal framing connectors– Used at many wood connections to strengthen

nailed connections• Joist hangers, post caps, post bases, and straps

• Bolts – Anchor bolts, carriage bolts, and machine bolts

• Washers keep bolt head and nut from pulling through the lumber and also spread stress

Common Connection Methods (cont’d.)

• Miscellaneous bolts– Stud, drift, expansion, toggle bolt

• Welds– Welding provides a rigid connection between two

or more pieces of steel• Fillet, square-groove, V-groove, beveled, U-groove, J-

groove weld• All-around or weld length and increment are used to

clarify placement