Mechanical Estimating Manual Episode 3 docx

Detailed estimating BUDGET ESTIMATES A conceptual budget estimate is a quick, approximate price without extensive quantity surveys or pricing calculations of the specifi c of items tha

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28 Mechanical Estimating Manual

Quantity Takeoff Sheet

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Sample HVAC Estimate and Forms 29

Estimate Summary and Extension Sheet

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Bid Recap and Markup Sheet

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Calculating Labor Costs Per Hour

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Telephone Quotation

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Bidding Record

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Section II

Budget Estimating

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There Are Three Basic Types of Estimates

1 Conceptual or budget estimating

2 Semi-detailed budget estimating

3 Detailed estimating

BUDGET ESTIMATES

A conceptual budget estimate is a quick, approximate

price without extensive quantity surveys or pricing

calculations of the specifi c of items that comprise a bid.

Contractors use conceptual budget estimates in the

following ways:

• To help determine if they should bid a job or not.

• To know approximately what the total price of a project

should be before preparing a detailed estimate.

• Quick pricing for customer, general contractor or A/

E.

• As a check of your estimate after you’re done.

• For budgeting purposes, comparing design costs,

feasibility studies.

• As a check on current market pricing.

• For negotiating.

• To check incoming bids and quotations.

There are two basic types of budget estimates, one

for budgeting the overall price of the project or trade, and

the other, the semi-detailed one, for budgeting individual

component parts and totaling for the job.

The conceptual estimate issued for overall pricing,

is a rough approximation based on some unit of

measurement of the building or system:

— 10,000 sq ft Offi ce Building @ $7.00/sq ft for

HVAC = $70,000

— 100 Tons of Air Cond in a Store @ $1500.00/Ton

= $150,000

— 100,000 sq ft High School @ $9.00/sq ft for sheet

metal = $900,000

Conceptual pricing should normally not be used

for bidding with any fi rm commitment on the price Your

price may be reasonably accurate, even right on, but it

also can be off the mark 20 to 25% one way or the other

due to variations in design, scope, etc.

You may look at an offi ce building, fi gure $7.00/sq

ft, fi nd out later, upon closer inspection or doing the job,

that this particular offi ce building runs $8.00/sq ft and

you lose $20,000 on a 20,000 sq ft job.

SEMI-DETAILED SCOPE BUDGET ESTIMATES Semi-detailed budget estimates, the second basic approach to pricing construction work is far more accurate than a conceptual one It is “on” more frequently and only has a potential inaccuracy of 10 to 15% while still being a very speedy way to price without the tedious, length takeoffs and extensions.

In semi-detailed estimating you break the job down into component parts, as you would a fully detailed one, listing all the individual items on a summary and extension sheet But instead of a long exact take off on each and extensive pricing, the quantities and the prices

of the various components are budgeted; i.e., they are approximated in some expedient manner.

A thorough preliminary survey is made, again, as you would on a fully detailed bid, to insure covering and knowing the entire scope of the project and so that spec requirements are met.

Ductwork Budgeting

Ductwork weight is approximated by using

an average weight per square foot of building, or by measuring the total linear footage with a measuring wheel, and multiplying it times the approximate average weight per linear foot.

Ductwork costs for the project are then found by multiplying the budget price per pound or per foot, based

on inspection and judgment, times the approximate weight or linear footage.

Piping Budgeting

• Main Piping Runs Per Foot

• Piping Assembly Hookups To Equipment Per Assembly Price

Equipment Pricing

Equipment costs are determined in one of two ways

If the equipment has been sized and specifi ed suppliers can furnish approximate pricing The second pricing is budgeting by the cost per CFK square foot, linear foot, etc or by the size Equipment labor is determined either

by the average size or the specifi c sizes.

Again, as with conceptual budget estimates, it is very risky business bidding fi rm quotes based on semi-detailed estimates However, you can chance it, when the situation demands it by adding 10 or 15% on top to cover the possible range of error.

Chapter 4

Budget Estimating

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DETAILED ESTIMATES

The only truly reliable estimate is the fully detailed

one which absolutely minimizes the risks of being far too

low or high, where the odds are greatly in your favor that

the estimate is a true representation of the job.

Budget Estimating HVAC Costs and Engineering Loads

Per Square Foot of Building and Per Ton

—————————————————————————————————————————————————

COOLING LOAD LOAD SUPPLY WEIGHT SELLING PRICE

Btu Per Sq Ft Btu Per CFM Per lbs Per Per Per

Sq Ft Per Ton Sq Ft Sq Ft Sq Ft Sq Ft Ton

—————————————————————————————————————————————————

Offi ce Bldgs: Low Rise 35 340 35 1.1 5 to 8 10.36 3,522

—————————————————————————————————————————————————

1 Cooling load based on is temp differences, 50% RH, 400 CFM per ton.

2 Heating load based on 70 temp differences and is the output Btu.

Apply ineffi ciency factor to heating equipment for input Btu.

3 Price includes all HVAC material, labor and subs and overhead and profi t.

*R-11 wall and R-19 ceiling insulation

In a detailed estimate the systems and work are broken down into the smallest type components and sizes

in which they can be priced with reasonable accuracy and practicality All items, are components, are taken off and priced separately by specifi c sizes, types, accessories, etc.

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Budget Estimating 39

Budget Estimating Galvanized Ductwork

Per Pound and Per Foot

Standard Low Pressure HVAC Rectangular Galvanized

25 Percent Fittings, New Construction, 10 Foot High, 1st Floor

——————————————————————————————————————————

—

PERIM LB/FT SQ FT/FT Furnished & Installed

——————————————————————————————————————————

*Selling price based on $.42 per pound for galvanized, $39.00 per hour for labor, a 30 percent markup on direct costs for

overhead and a 5 percent markup for profi t The price includes material and all labor for the fabrication, installation,

drafting and shipping

CORRECTION FACTORS ON SELLING PRICE OF GALVANIZED DUCTWORK

1 Percent fi ttings by weight,

15% 0.09 25% 1.00

35% 1.08 45% 1.15

2 Different wage rates (incl base pay, fringes, payroll taxes, ins.)

$12.00 (per hour) 0.66 $22.00 0.89 15.00 0.77 26.50 1.00

18.00 0.80 30.00 1.08

3 Overall residential factor for 15 percent fi ttings, $12.00 per hour gross wages and lighter gauges 0.50 times cost per lb

or per foot

Example: 24” x 8 $4.15/lb equals $2.08/lb

$31.90/ft equals $15.95/ft

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Installed Price Per Square Foot for Different Types of Ductwork

Average Size 24”x12” in a Typical Mix

25 Percent Fittings by Square Feet

Installed price per square foot includes material, shop labor, fi eld labor, shop drawings, shipping and

a 35 percent markup on costs for overhead and profi t Labor is based on $39.00 per hour.

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Per Square Foot Ductwork Cost Comparison

Average Size 24”x12”

25 Percent Fittings By Square Feet

per ft hr per per ft hr per 30% O&P per sq ft per hr sq ft per hr sq ft per sq ft

———————————————————————————————————————————————— STAINLESS 24 gauge with cleats $3.18 30 0.03 17 0.06 $8.81

18 gauge welded seams

————————————————————————————————————————— ALUMINUM 20 gauge 032” thick

————————————————————————————————————————— FRP 3/16” thick coupling

1-3.32

————————————————————————————————————————— PVC 1/8” or 3/16” thick

fl ange or slip connections 5.12 23 0.04 16 0.06 12.03

————————————————————————————————————————— PVC (PVS)

COATED 22 gauge with cleats or

————————————————————————————————————————— BLACK IRON metal fl anges, bolted,

—————————————————————————————————————————

————————————————————————————————————————— angle fl anges, bolted

—————————————————————————————————————————

16 gauge, kitchen exhaust welded connections, NFPA 96 1.42 16 0.06 10 0.10 10.09

————————————————————————————————————————— FIBER 800 board, stapled and

————————————————————————————————————————— GALVANIZED low pressure, unlined 0.74 38 0.03 22 0.05 4.60

————————————————————————————————————————— low pressure, 1” lining, 1-1/2 lb 1.47 22 0.05 21 0.05 6.62

————————————————————————————————————————— SPIRAL pipe and fi ttings, medium

pressure, slip connections sealed 0.75 47 0.02 24 0.04 4.17

———————————————————————————————————————————————— Sell budget prices include material, shop and fi eld labor, shop drawings, fi eld measuring, shipping, and a 30% markup for overhead

and profi t

*Material costs includes sheet metal, connection materials, hangers, scrap hardware

Labor rate $39.00 per hour

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Budget Estimating Insulation and Lining Per Foot

Standard HVAC Rectangular Ductwork

25 Percent Fittings by Square Footage

————————————————————————————————————————

PERIM SQ FT/FT Furnished & Installed

(w & d) Waste

————————————————————————————————————————

12x6 18 3.5 7.70 5.64

————————————————————————————————————————

72x30 102 19.6 43.14 36.81 72x36 108 20.7 45.55 38.86

84x36 120 23.0 50.63 43.19 84x42 126 24.1 53.04 45.26

————————————————————————————————————————

96x24 120 24.2 53.27 45.44 96x36 132 25.3 55.69 68.01 96x48 144 27.6 60.75 51.83 96x72 168 32.2 70.88 60.46 96x96 192 36.8 80.99 69.12

————————————————————————————————————————

1 Lining is based on 1 inch thick 1-1/2 pound density fi ber glass blanket at

$1.48 per sq ft installed Installed selling prices based on $39.00 per hour for labor, a 25 percent markup for overhead and a 5 percent markup for profi t Includes all pins, tapes, cement, materials and labor

2 Galvanized ductwork weight must be increased 12 percent to compensate for increasing the metal duct size one inch for the lining

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Budget Estimating External Insulation Per Foot

Standard HVAC Rectangular Ductwork

25 Percent Fittings By Square Footage

SIZE - With 15% & Installed

(w & d) Waste per ft

——————————————————————————————

1 External insulation based on 1-1/2 inch thick 3/4 pound density

fi ber glass with vapor barrier, at $1.72 per sq ft installed

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Budget Estimating Insulation

External Wrapping For Ductwork Per Square Foot

—————————————————————————————————————————————————

FIBER GLASS BLANKET, RFK

————————————————————————————————————————————————— FIBER GLASS, RIGID BOARD

————————————————————————————————————————————————— OUTSIDE.FIBER GLASS, RIGID BOARD

With 2 Layers black mastic, glass mesh 1 4 - 5.09

————————————————————————————————————————————————— KITCHEN EXHAUSTS & BREECHING

Calcium Salicate Block (K Block)

With 1/2” Cement

Fiber Glass, Rigid Board

—————————————————————————————————————————————————

*Includes 15% waste, pins, staples, tape, installation, supervision, 20% overhead and 5% profi t Based on union wages of $39.00

per hour, 10 foot high ducts, lower fl oors, normal space conditions

CORRECTION FACTORS

1 Congested ceiling spaces, areas 1.15

2 Wage rate at $39.00 per hour

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Budget Estimating Copper Tubing

Installed Price Per Foot

95/5 Solder, 300F

Includes 2 Fittings Per 20 Feet of Pipe, Hangers and Solder Standard Installation Conditions, Lower Floors, 10 Ft High

———————————————————————————————————————————

—————— —————— —————— —————— ——————

1/2 $9.32 $8.39 $10.03 $8.81

1 15.OB 13.26 16.71 13.93 1-1/4 18.97 17.08 23.41 17.95

1-1/2 21.70 19.54 23.77 20.51

—————— —————— —————— —————— ——————

2-1/2 38.36 33.68 41.00 35.36

———————————————————————————————————————————

Prices include all material costs, labor at $51.00 per hour and overhead and profi t markup

Budget Estimating Steel Piping Installed Price Per Foot

Includes 2 Fittings Per 20 Feet of Pipe, Hangers Standard Installation Conditions, Lower Floors, 10 Ft High

———————————————————————————————————————————

—————— —————— —————— —————— ——————

1/2 $8.54

—————— —————— —————— —————— ——————

2-1/2 23.68 24.61 40.17 19.24

—————— —————— —————— —————— ——————

12 168.54 129.93 253.97 135.76

———————————————————————————————————————————

Prices include all material costs, labor at $51.00 per hour and overhead and profi t markup

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Budget Estimating PVC Pressure Piping

Installed Price Per Foot

Includes 2 Fittings Per 20 Feet of Pipe, Hangers and Solvent Standard Installation Conditions, Lower Floors, 10 Ft High

—————————————————————————————

MATERIAL & LABOR

—————————————————————————————

3” 0.229 $12.90 $16.76 4” 0.317 $13.36 $17.37

—————————————————————————————

Direct labor costs are $39.00 per hour

Budget Estimating Cast Iron Piping, Hub and

Spigot Installed Price Per Foot

Includes 2 Fittings Per 20 Feet of Pipe, Hangers Standard Installation Conditions, Lower Floors, 10 Ft High

—————————————————————————————

MATERIAL & LABOR

—————————————————————————————

Direct labor costs are $39.00 per hour

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Threaded Bronze and Iron Valves

—————————————————————————————————————

TOTAL TYPE DIRECT LABOR MATERIAL & LABOR

———— ———— ————— ———— ——————————

GATE 1/2 Bronze $22.79 0.65 $48.14 $62.58 3/4 Bronze 29.53 0.72 57.61 74.89

1 Bronze 35.74 0.78 66.16 86.01

—————————————————————————————————————

2 Bronze 85.00 1.04 125.56 163.22

—————————————————————————————————————

CHECK

————————————————————————————————————— 1/2 Bronze $24.42 0.65 $49.77 $64.70 3/4 Bronze 27.65 0.72 55.73 72.44

1 Bronze 36.19 0.78 66.61 86.59

—————————————————————————————————————

2 Bronze 88.80 1.04 129.36 168.17

—————————————————————————————————————

BALL

————————————————————————————————————— 1/2 Bronze $7.87 0.65 $33.22 $43.19 3/4 Bronze 12.55 0.72 40.63 52.82

1 Bronze 16.10 0.78 46.52 60.48 1-1/4 Bronze 28.09 0.91 63.58 82.65 1-1/2 Bronze 35.74 0.98 73.96 96.15

—————————————————————————————————————

————————————————————————————————————— Direct labor costs are $39.00 per hour

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