Post-Construction Window Cleaning

Why this matters

Post-construction window cleaning is the highest-revenue per-job work in the window cleaning trade. A new construction home with 30 to 50 windows can yield a significant for a single visit; a new commercial building can yield a significant cost. The work is also the most demanding: windows are typically caked with construction debris (paint over-spray, joint compound dust, mortar, silicone caulk smears, sticker residue). Standard window cleaning methods fail; specialized scraping, solvents, and patience are needed. A contractor who can deliver post-construction cleaning to the spec the general contractor requires becomes a trusted source for new construction; the relationships generate ongoing residential work after the construction phase ends.

When to perform

• After all construction is complete (verify with the GC; some contractors are still working)
• Before occupancy
• After other trades have cleared (no more drywall sanding, painting, etc.)
• After exterior facade work is complete (siding, paint, masonry)

Typical contaminants

Tools and materials

• Squeegees (multiple sizes)
• Strip washers
• Razor scrapers (1.5 inch and 4 inch sizes)
• Steel wool (#0000 grade only; for glass; no other grade)
• Adhesive remover (Goof Off, Goo Gone, citrus-based)
• Mineral spirits
• Plastic scrapers (for vinyl, paint, frames)
• Mild detergent
• Water spot remover (for hard water deposits)
• Brushes (small detail brushes)
• Microfiber cloths
• Buckets
• Drop cloths (catch scrapings)
• PPE: gloves, eye protection, knee pads, fall protection

Safety considerations

Post-construction work involves:

• Working at heights (use proper fall protection)
• Chemical exposure (solvents, paint solvents)
• Sharp scraping tools (cut hazard)
• Dust inhalation (especially during dry scraping)
• Slip hazards (wet glass, drop cloths)

Procedure for typical post-construction window

Step 1: Survey and quote

Before starting:

• Walk the site
• Count windows and assess condition of each
• Note any windows that are heavily contaminated
• Identify the GC's specifications (per panel? hourly? complete cleaning?)
• Quote per the GC's specifications

GC pricing typically:

• Standard residential: a modest per window
• Commercial: a modest per window
• Per-pane vs per-window: clarify in the quote

Step 2: Test cleaning method on a sample window

Each construction site has different contaminants. Test:

• Try standard wet wash; observe results
• If wash doesn't remove contaminants, try scraping
• If scraping doesn't work, try chemical solvent
• Confirm the right method before scaling to all windows

Step 3: Surface preparation

For each window:

• Wet the surface (loosens dirt; reduces dust)
• Scrape if needed (always wet; never dry)
• Apply solvent if needed (small amount; rinse promptly)
• Allow time for the contamination to soften

Step 4: Wash and rinse

After preparation:

• Wash with detergent solution
• Use the squeegee with the strip washer technique
• Rinse with clean water
• Dry with microfiber

Step 5: Detail work

Pay attention to:

• Corners (where contamination collects)
• Edges of frames (where caulking smears appear)
• Lower edges (water collects)
• Specific contaminants (sticker residue, paint dots)

Step 6: Inspect under good lighting

After cleaning each window, inspect under:

• Direct sunlight (reveals smudges and streaks)
• Off-axis lighting (reveals haze)
• Up-close inspection (catches missed spots)

Customer's inspection will be tough; theirs needs to find nothing.

Step 7: Document and walk-through

• Photograph the cleaned windows (after each significant section)
• Walk through with the GC or construction manager
• Address any concerns

Step 8: Reapply for any rework

If you must come back:

• Verify the issue
• Determine cause (typically: contamination missed during initial; reapplied due to ongoing construction nearby)
• Reclean affected areas

Working with general contractors

Post-construction is typically a GC contract; the GC pays you.

Pre-bid conversation

Before quoting:

• What's the spec? (visible cleaning, microscopic cleanliness, etc.)
• When does construction complete?
• When does occupancy?
• What's the timeline window between these dates?
• Who's paying? GC or owner?
• Where's the dispute resolution?

Quote presentation

Provide a written quote with:

• Number of windows
• Pricing structure
• Estimated days for completion
• Materials and methods to be used
• Standard for completion (visual inspection, GC sign-off, etc.)
• Payment terms

During the work

• Coordinate with GC on access
• Track which trades are on site (other trades can re-contaminate)
• Document progress daily

Completion

• GC sign-off on completion
• Photographs of final state
• Final invoice

Coordinating with other trades

A construction site has many trades:

• Drywallers and painters often leave debris that affects windows
• Roofers (over-spray of sealants)
• HVAC installers (filter dust)
• Cleaners often work after window cleaning

Recommend completing window cleaning AFTER all other trades are done. If window cleaning happens too early, re-contamination requires re-cleaning at no additional charge (usually).

Quality criteria

The GC's spec for completed work typically:

• Visible cleanliness under normal lighting
• No visible streaks
• No water spots
• No paint over-spray remnants
• No sticker residue
• Frames and tracks cleaned (often included; sometimes separate)

For premium specifications (hospitals, museums):

• Microscopic cleanliness
• Specific cleaning protocol
• Documentation

Common post-construction problems

Tempered glass scratches

References

• IWCA (International Window Cleaning Association) standards.
• ANSI / IWCA I-14.1.
• AGC (Associated General Contractors) post-construction cleanup specifications.
• Manufacturer literature: glass manufacturers (Cardinal, Guardian, Pilkington) on glass care.
• Manuall internal: Universal Documenting Service for Insurance.