Job-Specific Estimating: Material and Labor Calculations Flashcards

A C-33 contractor must paint 2,400 sq ft of smooth drywall with two coats. The paint covers 350 sq ft per gallon. Accounting for 10% waste, how many gallons are needed?

Answer: 15 gallons

Two coats x 2,400 sq ft = 4,800 sq ft. At 350 sq ft/gal: 4,800/350 = 13.7 gal. With 10% waste: 13.7 x 1.10 = 15.07, rounded to 15 gallons.

When estimating labor for exterior painting, which surface type typically requires the MOST labor hours per 100 square feet?

Answer: Ornamental wrought iron

Ornamental wrought iron requires the most labor due to its complex geometry and need for careful brush work on intricate details.

A bid requires painting 80 windows (standard double-hung, 3x5 ft). Industry standard production rate is 4 windows per hour for brush and roller. How many labor hours should be estimated?

Answer: 20 hours

At 4 windows per hour: 80 windows / 4 = 20 labor hours for the painting operation alone.

A C-33 contractor is pricing a commercial repaint. The overhead rate is 45% and desired profit margin is 12%. If direct costs are $22,000, what is the correct bid price?

Answer: $36,250

Direct costs $22,000 + overhead (45%) $9,900 = $31,900. For 12% profit margin: $31,900 / (1 - 0.12) = $36,250.

When estimating paint for a room with standard 8-foot ceilings, which shortcut formula gives approximate wall area?

Answer: Room perimeter x ceiling height, minus 20 sq ft per door and 15 sq ft per window

Wall area = room perimeter x ceiling height. Then subtract approximately 20 sq ft per standard door and 15 sq ft per standard window for openings.

A C-33 contractor uses an airless sprayer rated at 0.6 gallons per minute. At 70% transfer efficiency, how many gallons of paint are actually deposited on the surface per hour?

Answer: 25.2 gallons

Output: 0.6 gal/min x 60 min = 36 gal/hour. At 70% transfer efficiency: 36 x 0.70 = 25.2 gallons deposited per hour.