Painting Scope of Work: What GCs Need to Include When Buying Out a Painting Sub

Painting is one of the last trades on site and one of the most frequently underscoped. The painting scope of work is where quality failures become visible — and where callbacks happen after the owner has moved in. A complete painting scope of work defines not just what gets painted, but how surfaces are prepared, what paint systems apply to each substrate, how many coats are required, and who is responsible for protection, scheduling, and deficiency correction. This guide covers what to include in a commercial painting scope of work, organized by the trade-specific work, package items, and coordination requirements.

Surface Preparation

Tip: Surface preparation is the most important and most commonly underspecified item in any painting scope of work. The quality of a paint job is determined almost entirely by prep. Specify it in detail — do not leave it to the sub's discretion.

• Drywall and gypsum board: All nail/screw holes, joints, cracks, and surface defects must be filled, sanded, and spot-primed before painting. Specify acceptable surface profile — Level 5 finish (skim coat) is required for any wall or ceiling receiving gloss or semi-gloss paint or receiving raking light. Level 4 is standard for most flat commercial interiors. Confirm which level is required by area on the finish schedule.
• Concrete and masonry: Surface must be clean, dry, and free of efflorescence, form release agents, curing compounds, and laitance. Specify surface preparation method — wire brush, grinding, acid etching, or pressure washing by area. Concrete must reach minimum 28-day cure before painting. Apply alkali-resistant primer on all new concrete and masonry.
• Ferrous metals (structural steel, hollow metal frames, miscellaneous steel): Specify surface cleanliness standard — SSPC-SP2 (Hand Tool Cleaning) minimum for shop-primed steel requiring touch-up; SSPC-SP6 (Commercial Blast) minimum for uncoated steel receiving a full coating system. Touch up all shop primer damage and weld spatter before applying finish coats.
• Wood and millwork: Fill all nail holes, grain, and open joints with appropriate filler. Sand to 150-grit minimum between coats. Raised grain on wood receiving water-based products must be sanded after the first coat. Back-prime all wood trim before installation where accessible.
• Existing surfaces (renovation work): Specify scope of surface preparation for existing painted surfaces — clean, degrease, sand glossy surfaces to achieve mechanical bond. Identify areas requiring removal of failed, peeling, or contaminated existing paint.

Paint Systems by Substrate and Area

Tip: Best GCs specify paint systems by a combination of substrate type and occupancy type — not a single specification for the whole building. A wet area like a washroom requires a different system than a drywalled office corridor.

• Interior drywall — general areas: One coat alkyd or latex primer; two coats latex eggshell or flat finish as indicated on finish schedule. Specify primer and finish coat by manufacturer and product name — not just "approved equal."
• Interior wet areas (washrooms, kitchens, mechanical rooms): One coat moisture-resistant primer; two coats semi-gloss or gloss latex or alkyd finish. Semi-gloss minimum in all wet areas — flat finishes in wet areas absorb moisture and grow mould.
• Concrete floors: Specify coating system type — epoxy (two-component) for high-traffic or chemical-exposure areas; urethane for areas requiring UV stability; acrylic for light-duty. Confirm substrate moisture content maximum before coating (typically 5% by weight). Coating applied to wet concrete delaminates — this is the most common concrete floor coating failure.
• Structural steel: Specify full coating system: primer coat (zinc-rich or epoxy primer), intermediate coat (epoxy), and finish coat (polyurethane for exterior or high-traffic; alkyd for typical interior). Number of coats and minimum DFT (dry film thickness) per coat must be in scope.
• Hollow metal doors and frames: Specify touch-up of shop primer on all damaged areas, then two coats of semi-gloss alkyd or water-based enamel finish. Door frames that receive primer touch-up only — without finish coats — are a common painting scope gap.
• Exposed ductwork and piping (if in scope): Confirm whether exposed mechanical systems are in the painting sub's scope or the mechanical sub's scope. This is a consistent gap. If in painting scope, specify system, color coding requirements, and whether identification labeling is included.

Application Requirements

• Number of coats: Specify minimum coat count by system. "Two coat" without specifying dry film thickness (DFT) allows the sub to apply two thin coats that together barely meet one coat's coverage — specify both coat count and minimum total DFT.
• Dry film thickness (DFT): Specify minimum DFT per coat and per total system for all coating systems where film thickness matters (floor coatings, structural steel, exterior coatings). Require the sub to submit DFT test records for spot checks in each area.
• Sheen levels by area: Provide a finish schedule by room or space type specifying sheen level — flat, matte, eggshell, satin, semi-gloss, or gloss. Without this schedule, the sub will apply whatever sheen they have on hand.
• Spray vs. roller vs. brush: Specify acceptable application methods for each area and substrate. Spraying in occupied buildings requires additional masking and ventilation — confirm method is acceptable to the owner and building operator before issuing the subcontract.

Protection of Adjacent Work

• Masking and drop cloths: All hardware, glass, flooring, finished millwork, and mechanical equipment must be protected during painting. Specify that the painting sub is responsible for all masking and protection materials and for any damage caused by paint overspray or spills.
• Hardware removal and reinstallation: Best practice is to remove all door hardware (hinges, closers, locksets) before painting and reinstall after. Many painting subs mask in place — which produces visible paint lines and incomplete coverage. Specify removal/reinstallation explicitly if required.

• Paint sample submittals: Sub submits minimum two drawdown samples of each color and finish for architect or owner review and approval before any painting begins. Samples on the actual substrate used on the project — not on white card stock. Revisions to color selections after painting has started are the painting sub's most common source of disputes.
• Maintenance stock: Specify quantity of each paint and stain product left with the owner at closeout — typically 3.8L (1 US gallon) per color per building. Label all containers with color name, manufacturer product number, and area applied. Without this, building owners cannot match touch-ups.
• Warranty: Specify warranty period by product type — typically 1 year labor and materials for interior; 3–5 years for exterior. Confirm whether the sub's warranty covers paint material defects only or includes delamination, peeling, and deficient surface preparation.
• Final inspection and deficiency correction: Specify that the painting sub conducts a pre-completion walkthrough with the GC before demobilizing and corrects all holidays, thin spots, poor coverage, and colour discrepancies before releasing final payment.
• Ventilation during painting: Sub is responsible for providing adequate air movement and ventilation during application to meet VOC requirements, achieve proper cure, and comply with OH&S requirements for solvent-based products. If the building's HVAC system is not yet operating, the sub provides temporary ventilation.
• Touch-up after other trades: Specify whether the painting sub returns after final trades (millwork, electrical devices, plumbing fixtures) for touch-up, and how many return visits are included. Touch-up after possession is a separate scope item — confirm explicitly.

• Drywall and finishing trades: Painting cannot proceed until all drywall finishing, joint compound, and skim coat work is complete and dry. The drywall trade must notify the GC when each area is ready for paint inspection. Painting sub must inspect surfaces and report deficiencies before accepting the area — once primer is applied, the painting sub owns surface quality.
• Millwork and casework: Confirm whether casework, doors, and trim are painted before or after installation. Pre-finishing before installation produces better results but requires protection during installation. Specify the sequence in the construction schedule.
• Electrical: Confirm whether cover plates, device plates, and panel covers are on or off during painting. Best practice: off during painting, reinstalled after. Coordinate with the electrical sub — paint overspray on electrical panels and devices is a fire and safety issue.
• Mechanical/HVAC: Confirm whether exposed ductwork, piping, and mechanical equipment receive finish paint, and whether the mechanical sub's touch-up primer is acceptable as the finished surface or whether the painting sub applies additional finish coats.
• Flooring: Painting before floor installation avoids floor damage from paint drips but leaves an unpainted strip at the base of walls once flooring is installed. Coordinate the sequence — base coat before flooring, touch-up after — and specify it in the scope.
• Glazing and glass: Specify that the painting sub masks all glass before beginning work and removes all paint overspray from glass before demobilizing. Paint on glass is an owner deficiency list item on virtually every project — address it in the scope.