Contractor's License

Contract documents include the agreement, general conditions, supplementary conditions, specifications, drawings, and addenda. When conflicts exist, documents higher in hierarchy govern. Typically, written dimensions govern over scaled dimensions, large-scale details govern over small-scale drawings, and specifications govern over drawings for material and product requirements.

Addenda issued before contract signing modify original documents. Change orders issued after contract signing modify the contract through formal procedures.

Division 01 establishes administrative and procedural requirements applying to all work. Sections address summary of work, price and payment procedures, administrative requirements, quality requirements, temporary facilities and controls, product requirements, execution and closeout requirements.

Submittals require contractors to provide product data, shop drawings, samples, and certificates for approval before incorporating materials. Shop drawings show fabrication and installation details for custom items. Product data includes manufacturer specifications and installation instructions.

Technical specifications describe materials, products, and execution for specific work categories. Each section typically includes general provisions, products, and execution. General provisions establish scope, related work, references, submittals, quality assurance, and delivery and storage requirements. Products specify acceptable manufacturers, materials, and fabrication. Execution describes preparation, installation, and field quality control.

Reference standards from organizations like ASTM, ANSI, ACI, AISC, and AWS establish material properties and testing methods. Contractors must understand which standards apply and ensure compliance.

Quantity takeoff extracts material quantities from construction documents for estimating purposes. Accurate takeoff requires systematic methods and attention to detail.

Linear items include trim, baseboards, gutters, piping, and wiring. Measure lengths from drawings, adding allowances for waste and connections. For perimeter calculations, measure carefully around corners and openings.

Area items include flooring, roofing, painting, drywall, and insulation. Calculate areas by multiplying length times width. For irregular shapes, divide into rectangles and triangles. Roof areas must account for slope using slope factors. A 4:12 slope has a factor of 1.054, meaning 100 square feet of plan area requires 105.4 square feet of roofing.

Deduct openings appropriately. For painting, deduct window and door openings. For drywall, some estimators deduct openings over certain sizes only. Establish consistent rules.

Volume items include concrete, excavation, fill, and gravel. Calculate volumes by multiplying length times width times depth or height. For excavation, include allowances for working space around foundations. For concrete, convert cubic feet to cubic yards by dividing by 27.

Bank cubic yards represent undisturbed soil. Loose cubic yards account for swell when excavated. Compacted cubic yards account for shrinkage when compacted. Conversion factors vary by soil type.

Count items include doors, windows, fixtures, outlets, and equipment. List each item by type and size. Group similar items for pricing efficiency.

All quantity takeoffs require waste factors. Framing lumber typically includes 5 to 10 percent waste. Drywall includes 5 to 10 percent. Roofing shingles include 10 to 15 percent for starter courses, ridges, and cutting. Concrete includes 3 to 5 percent for over-excavation and spillage.