bcn5618 su12 module4

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Master of Science in Construction

Management – UNIBE

BCN 5618 Fundamentals of Construction Estimating

Module 4

José A. Faria, Ph.D.

1 BCN 5618 Fundamentals of Construction Estimating

DIV. 5 METALS

Metals

• Includes– Structural metal framing– Metal joists– Metal decking


g– Metal fabrications– Ornamental metal– Expansion control assemblies

• Materials:– Iron, steel, aluminum, brass, bronze, etc.

Structural steel

• Has replaced much of the structural concrete in multi‐story buildings.

• There are three structural categories:H t t l t l


– Heavy structural steel

– Light‐gauge structural steel

– Miscellaneous steel

Heavy structural steel

• Minimum of ¼” thick.

• Wide‐flange structural steel beams (W, WF), structural narrow‐flange beams (I,S), miscellaneous or junior structural beams (M), channel steel (C),


angle iron (L), structural tubing (TS), Pipe (Pipe) and plates

• Need to count pieces, their weight and then calculate total weight. This is for purchasing purposes and to select the crane size.

Heavy Structural Steel

• Denomination of beams, channels and tees is the letter followed by nominal depth and weight per foot– W12x40 is a Wide Flange beam with a nominal


– W12x40 is a Wide‐Flange beam with a nominal depth of 12inches and a weight of 40lb/ft

– S18x70 is an American Standard beam with nominal depth of 18” and a weight of 70lb/ft

– C12x30 is a Standard Channel wit h nominal depth of 12 in and weight 30lb/ft

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• Angles are designated by an L followed by the longest leg, the length of the other leg, and the thickness of the angle– L5x3x1/2 is an angle with one leg measuring 5in


– L5x3x1/2 is an angle with one leg measuring 5in, the other leg measuring 3inches and a thickness of ½ inch


• Structural tubing used for columns and cross bracing in the construction of steel trusses designated by TS followed by the length of the longest cross sectional axis the length of the


longest cross sectional axis, the length of the other axis, and the thickness of the wall– TS4x4x1/2 is a structural tubing with a cross section of 4”x 4” and wall thickness of ½”


• Pipe is typically used for columns. Designation is “Pipe” followed by the nominal diameter of the pipe and the type of pipe– Pipe 4 std is a pipe 4” in diameter and standard


– Pipe 4 std is a pipe 4 in diameter and standard weight.

– The 4” standard pipe has a wall thickness of 0.237 in, a weight of 10.79 lb/ft, inside diameter 4.026 in and outside diameter of 4.5 in


• Plates are used as base plates and connectors, the designation is the thickness

• Weight is 490 lb/cft



• Joists are designated by the depth followed by a letter (K is the most common) and the section number. The larger the section number the strongest the joist


number the strongest the joist– 24K3 is 24” depth K series joist with a section number of three


• Girders are designated by the depth followed by the girder series, number of spaces and load on each panel point– 24G5N8K is a 24” deep joist girder with five


– 24G5N8K is a 24 deep joist girder with five spaces and each panel supports 8k (8000) pounds

• The number of spaces is one more than the number of joists that are supported by the girder

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Steel symbols and shapes


Light‐gauge structural steel

• Structural light‐gauge steel refers to metal studs and joists ranging in thickness from 18 gauge to 12 gauge. The smaller the gauge the thicker the steel


• Punched studs are used in areas where it might be necessary to install other materials, plumbing or electrical work.

• Unpunched studs are commonly called joist, used for floor and ceiling and roofing.

Light‐gauge structural steel

• Steel decking is also part of the light‐gauge steel. It is available in several patterns .


Miscellaneous steel

• The most common is the open‐web steel joist constructed with a combination of structural iron and tubular steel pieces welded or bolted together


together.

• These are very common in large flat roof construction for industrial and commercial applications.

Open web joist


Costs

• Cost of the structural steel at the mill

• Freight

• Cost of shop drawings


• Cost of assembling and fabrication including templates, bolts and welds

• Cost of painting

• Cost of labor and equipment to erect the steel

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Steel Shapes


W S C WT

PLATEPIPETSL

Weight of Beams and Columns

• Weight = Length × Weight Per Length

• Approximate weight is 490 lb/cft

• Multiply the cross sectional area by 1ft to b i h i h li f


obtain the weight per linear ft

• Aluminum and steel are sold by weight, the takeoff is made in pounds and converted to tons (1ton = 2000lb)

• Cost about $30 / 100 lb

Connections


Productivity and cost

• Bolts– An iron worker places about 150 – 200 bolts per 8hr day

– Need compressor and operator


– Cost about $3.70 per bolt

• Welding– Depends on wall thickness, location, ease of access, etc.

– Need to go to tables or ask a contractor

Steel Joists


Joists and Joist Girders

• Joists are counted items• Joist girders are counted items


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Metal Decks


Metal Deck

• Metal deck is a sheet good


Trusses and Handrails

• List components– Include welding and bolts


Roof Frame Plan


Steel Joists


End Anchorage


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Erecting Steel

• Crane

• Operator

• Iron worker


• Cost about $47 / ton


DIV. 6 WOOD, PLASTICS, AND COMPOSITES

Subdivisions

• 06 00 00 Wood Plastics and Composites• 06 10 00 Rough Carpentry• 06 20 00 Finish Carpentry• 06 40 00 Architectural Wood Work

BCN 5618 Fundamentals of Construction Estimating 2

• 06 40 00 Architectural Wood Work• 06 50 00 Structural Plastics• 06 60 00 Plastic Fabrications• 06 70 00 Structural Composites• 06 80 00 Composite Fabrications

Wood• Has been used for thousand of years as a source of

heat and as a construction material for millions of items• It is an abundant renewable resource• Good resistance to compression• Available in different shapes colors treatments


Available in different shapes, colors, treatments, • Wood for construction is commonly known as lumber in

America. The sawn planks ready to be used are known as timber

• Engineered wood is a group of wood based products that are glued together to form a more efficient composite product.

Plastics• Is a synthetic or semi-synthetic solid that is

moldable. Usually organic polymers of high molecular mass derived from petrochemicals.

• Usually classified by their chemical structure: acrylics, polyesters, silicones, polyurethane,

d h l d l i


and halogenated plastics.• There are many other classifications depending

on their physical characteristics, chemical content, molecular structure, thermal response, and others.

• Their use is very wide in our society due to the low cost and high versatility

Composites

• These are engineered materials that are made as a combination of other materials to obtain desired physical characteristics


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Wood uses in Construction

• One of the most common applications of wood in construction is the wood frame construction


construction.• See the handout "Details for conventional

wood frame construction by the American Wood Council"

Measurement of Wood Items

Platform frame constructionLi


•Linear•Area•Volume

Floor Systems

• Sills are a linear component– Must be a naturally durable or pressure-treated wood

• Posts are a counted item• Girders are a counted item


Girders are a counted item• Joists are a counted item• Rim joists are a linear component• Blocking is a linear component

Heavy timber construction

• Commonly used as shoring for miles, rail ties, poles, support for wooden bridges, etc.

• Some buildings such as barns or barn-like


• Some buildings such as barns or barn-like use heavy timber beams and columns.

• In other applications heavy timber can be used as decoration to provide a rustic look

Fabricated structural wood

• Glue-laminated wood beams are used to replace large timber beams.

• A smooth finish beam is called architectural beam when a semi-smooth finish is used


beam, when a semi-smooth finish is used the beam is called structural beam

• Solid truss is common in residential applications

• Open web joist similar to metal ones can be made with wood

• Wood structure


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Wood treatment

• There are three typical wood treatment:– Fire retardant– Termite protection– Moisture resistant


Moisture resistant

Sill plates

• Whenever wood meets masonry or concrete or where wood is used below grade a sill plate is required, it could be redwood or treated lumber


redwood or treated lumber• Sill plates are most commonly 2 x 6, 2 x 8,

and 2 x 10 and are typically placed around the perimeter of the building

Floor Systems

• Engineered I-Joists often require web stiffeners at bearing points


Floor systems

• Floor joists• Header joists

• Joist hangers• Bridging


Floor framing• Girders• When the building is of a width greater

than which the floor joists can span, a beam of some type is required.


• A build up wood member, referred to as girder is used.

Girders


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Floor Systems• Openings require:

– Doubled trimmers if over 4 feet wide– Framing anchors on joist headers if over 6

feet wide


Floor Systems• Floor sheathing is a sheet good• Wood decking is a sheet good• Separate each item into the various

length and sizes required then convert t th d t th d f t b d


at the end to thousand feet-board measure (mfbm)

Where:N= Number of feet-board measureP = number of pieces of lumberT=thickness of lumber in inchesW = width of lumber in inchesL = length of pieces in feet

One board foot is equal to the volume of a piece of wood 1 inch thick and 1 sqft

Walls

• Top and bottom plates are linear goods• Studs are a counted item

– Two extra studs are needed at corners– Two extra studs are needed at intersections


– About two extra studs are needed for door openings– Up to seven extra studs are needed for window openings

eight feet or less in width

Walls

• Headers are a counted item– Headers constructed of 2× materials require

a ½ inch plywood spacer (for 2×4 walls) or two ½ inch plywood spacers (for 2×6 walls).


p y p ( )• Hold downs are a counted item• Blocking is a linear component• Wall sheathing is a sheet good• Nails are estimated by weight

Nails


Nails


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Wall Opening


Wall Opening


Typical Wall Section


Roof Systems

• Rafters are a counted item• Trusses are a counted item• Roof sheathing is a sheet good


Typical Wood Truss Shapes


Roof Systems

• Soffit is a sheet good


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Finish Carpentry and Cabinets

• Trim is a counted item• Shelving is a counted item• Paneling is a sheet good

Cabinets are a counted item


• Cabinets are a counted item


DIV. 7 THERMAL AND MOISTURE PROTECTION

Subdivisions• 70 00 00 Thermal and Moisture Protection• 07 10 00 Damp-proofing and Water-proofing• 07 20 00 Thermal Protection• 07 30 00 Steep Slope Roofing• 07 40 00 Roofing and Siding Panels


g g• 07 50 00 Membrane Roofing• 07 60 00 Flashing and Sheet Metal• 07 70 00 Roof and Wall Specialties and

Accessories• 07 80 00 Fire and Smoke Protection• 07 90 00 Joint Protection

Thermal and Moisture Protection

• Include all materials used to seal the exterior of the building to prevent moisture, heat and air penetration


heat and air penetration


• Thermal protection– Include insulation materials to reduce the

transmission of heat through the exterior envelope.


p• Moisture protection

– Waterproofing and dampproofing: Include coatings below and above grade to prevent moisture migration


•Insulation and Damp-Proofing - membranes used to keep heat and moisture outside of the building

•Roofing – uppermost surface of structure•Siding – vertical surfaces of structure•Flashing - thin metal or plastic sheet installed to prevent the passage of water into the structure


•Caulking and sealants to seal areas•Skylights , roof accessories, gutters, downspouts•Fireproofing - application of materials that make the structure more resistant to fire

•Joint Sealants and Caulking - materials used to seal joints or seams in various structures or piping

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Masonry veneer

• Water penetration in masonry veneer construction can occur at the base of the wall. Ideally, flashing should be installed continuously along the base of the wall


continuously along the base of the wall. This would eliminate the need to lap the flashing. However, this is rarely possible, so laps must be made. Flashing should be lapped a minimum of 6 inches.

Masonry veneer


Masonry veneer

• The cavity can include insulation, which is typically in the form of rigid foam, increasing the thermal performance of the wall


wall.

Information

• Look at architectural drawings for details– Roof sections for flashing, sheet metal,

insulation, and accessories– Wall sections for insulation, air barriers and


vapor barriers– Building sections for floor insulation – Walls and foundations

Waterproofingcost per sqft

• Methods:– Integral method: additives mixed with concrete– Membrane: synthetic material applied to the

surface (include lap as additional material)


( p )– Metallic or trowel-coat waterproofing: requires

surface preparation, cleaning, repair and application.

– Liquid membrane: requires surface preparation, cleaning, repair and application.

Dampproofingcost per sqft

• Typically applied below grade not intended to resist water pressure

• Methods:Spraying


– Spraying– Painting– Troweling a bituminous coat on areas– Parging: plastering a cement based mixture on

areas– Liquid-applied

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Roofing

• These are the materials included to cover the roof deck. Including:

– Bituminous materials placed over the deck– Flashing


Flashing– Shingles and nails (allow one extra course of

shingles at the eaves)– Include 5 – 8% waste and consider 1-1/2 to 3 lb

of nails per 100 sqft

Insulationcosts typically per sqft

• Need to specify R value (higher values of R provide better protection) and width

• Blankets or rolls of insulation called battsare installed between the studs.


• Rigid insulation required in some cases to maintain shape. Need to include fasteners, glue, and caulking.

• Some insulation comes with vapor barrier• Loose-fill insulation measured in bags

Vapor Barrier

• Calculated per sqft and separated by different thickness

• Consider laps, add 5% - 10% of overall area


area.

Air infiltration barriers

• Calculated per sqft of wall area and converted to rolls

• Installed at exterior of sidewall, under the siding


siding.• Popular with changes in energy codes

Vapor Barrier

Example


Exterior siding

• Available in different materials accounted per sqft

• Include trim and accessories accounted per lft


per lft• Include soffit and fascia accounted per sqft

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RoofingMajor components:

– Insulation– Waterproofing membrane– Protective surfacing– Flashing and counterflashing– Metal perimeter termination

Types– Built-up– Single Ply– Metal– Shingles/tiles

Take off quantities:


qRoof insulations and felps: per sqftBitumen: weight per sqft converted to total weightMineral surfacing: weight per sqft convereted to total weightFlashings, counterflashings, gravel stop and wood: per lftSealant material: per lftTrim pieces: by lftShingles and tiles: Gutters and downspouts: by lftStucco: by sqft may be converted to sqyExterior Insulation and Finish System (EIFS): bysqft

Firestop systems and sprayed fireproofing

Firestop systems• Materials used to fill the

space around penetrations through

ll d fl

Sprayed fireproofing• Material is directly

sprayed on a building’s structural component to

hi fi d


walls and floors• Measured in cft

achieve fire endurance rating

• Measured in cft


DIV. 8 OPENINGS

Subdivisions

• 08 00 00 Openings• 08 10 00 Doors and Frames• 08 30 00 Specialty Doors and Frames• 08 40 00 Entrances, Storefronts, and


Curtain Walls• 08 50 00 Windows• 08 60 00 Roof Windows and Skylights• 08 70 00 Hardware• 08 80 00 Glazing• 08 90 00 Louvers and Vents

Openings

•Openings consist of:– Doors– Frames– Glazing


Glazing– Hardware to cover the openings

For both interior and exterior openings

Doors

• Include residential prehung doors, commercial wood and hollow metal doors

• Most plans have a door schedule with an ID


ID• Each door has a unique identification,

each type of door typically has a unique identification too.

• Doors are counted items

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Door types

•Doors typically are swing or sliding•Glass residential sliding doors are provided by window suppliers, and are accounted under windows


under windows.

Doors

• Doors can be classified as panel, flush or slab and combinations of them.

• Doors can be made of metal, wood or plastic


plastic.• For metal doors, there is a metal frame

welded together and installed during the rough framing or masonry installation. The door can be installed at a later day.

Doors

• Doors can be manufactured in standard size or custom made

• Doors are counted items


Door Hardware

• Hinges• Locksets• Cylinders,

Sometimes the door comes with frame and all hardware. If not you need to include:


• Doorstops• Thresholds• Weather stripping• Closers• Panic hardware

Windows

• Windows can be classified as fixed glass, sliding glass, single or double hung, awning, hopper, casement, projected, jalouisie or a combination of them


jalouisie or a combination of them.

Awning Windows

Casement Windows

Double Hung Windows

Fixed Windows

Bay WindowsJalousie Windows

Hopper Windows

Windows

• Include windows and sliding glass doors• Each window has a unique identification,

each type of window typically has a unique identification too


identification too.• Windows are counted items

bcn5618 su12 module4

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