$2M CGL insurance + WSIB
Working at Heights certified
7 Inverleigh Dr, Etobicoke
New windows are supposed to be the easy part of a construction project. Then the trades leave, and the glass has concrete splatter, installation tape, cured silicone, and a film of dust that regular window washing does not touch. On this Toronto building our first method failed, and it took hand washing, a concrete dissolver, scrapers and fine steel wool to get every pane back to clear glass.
The job: a 3-storey community centre beside two construction sites
Quick answer: DT Cleaning quoted $800 for inside-and-outside window cleaning at the Sumac Community Food Centre in Toronto, a 3-storey restored brick building with a new glass entrance. A 2-technician crew took the job in July 2026, with 2 active construction sites working directly beside the property.
It is a good building: a heritage brick shell restored as a community food centre, with a modern glass entrance wall and a metal-clad addition grafted on. Every window is new. Right beside it, the neighbouring lots were wrapped in scaffolding and still under active construction.
The construction next door shaped most of how this job went. Post-construction glass is hard work on its own, and next to an active site it gets harder, because the air keeps putting dust back on the glass while you work. Two of us took the building together, since there was far more glazing than one technician covers in a day.
The work ran under our standard commercial coverage: $2M in Commercial General Liability insurance, full WSIB coverage, and Working at Heights certification per the Ontario Ministry of Labour standard. Several exterior panes on this building could only be reached from open steel fire-stair platforms, so the crew relied on that training.
What construction left on the glass
Quick answer: The windows had 4 kinds of construction residue: concrete splatter from masonry work, installation tape and its baked-on glue, cured silicone smears from the window install, and fine dust from the 2 sites next door. The client believed the windows had been cleaned before, but the glass showed no sign of a real post-construction clean.
The client told us the windows had been cleaned before, and we believe them. Judging by what we found on the panes, whoever did it ran a standard wash with soap, water and a squeegee. That removes dirt but leaves construction residue where it is.
Construction dust needs more care than ordinary dirt. Part of it is crystalline silica from cut concrete and masonry, a recognized workplace hazard that Canada's CCOHS documents in detail. For the glass, the problem is that silica grit is abrasive: rub a dry cloth across a dusty pane and you are sanding it. On this job we flooded every pane with water before any tool touched the glass.
The water-fed pole mistake we admit to
Quick answer: DT Cleaning started this job the fast way, with a water-fed system spraying the windows from below, which works on a normal building. Here, dust from the 2 active sites next door got into the rinse water, and every panel dried with streaks and residue on the frames. The crew wrote off the lost time and switched to washing everything by hand.
Our default for a building this size is the water-fed pole: spray, agitate, rinse, let it dry spotless. It is fast and safe from the ground, and on a normal exterior it gives excellent results, so that is how we started here.
That was our mistake, and the most useful lesson of the whole job. The spray rinsed the frames well enough, but the water sheeting off the glass picked up the construction dust on every surface above and around each window. Dust-loaded water dries as a faint grey film with streaks along the frames, which on brand-new black frames might as well be a signature. We looked at the first dried panels, accepted the lost time, and changed the plan.
"On a normal house the pole finishes the job. Next to a live construction site, the pole just moves the dust around with better pressure. You look at the dried panel and it tells you: start over, by hand."
DT Cleaning crew lead, July 2026
Everything after that was by hand: soap the pane, work the frames, scrub where needed, squeegee, and towel the edges dry before airborne dust could settle into the water film. It was slower per window, but each pane dried clean the first time.
How we take concrete off glass
Quick answer: Concrete splatter comes off glass with a dedicated concrete dissolver: apply the product to each spot, let it work for 5 minutes, then rinse the softened material away or lift what is left with a metal scraper held flat to wet glass. Scraping untreated concrete dry is how panes get scratched.
Most cleaning products do nothing to concrete on glass, because it is a mineral bonded to the surface. Muscle is the wrong tool, so we use chemistry first and steel second:
- Apply a concrete dissolver to each spot. It is a purpose-made acidic product that attacks the cement binder.
- Wait 5 minutes. The product does the work during this dwell time, softening and breaking down the splatter while you handle the next pane.
- Rinse and wipe the softened material away. Most spots come off at this stage with nothing sharper than a cloth.
- Scrape what is left, wet. Whatever remains gets a metal scraper on flooded glass, blade flat and moving in one direction. Wet glass, a flat blade and a slow pace keep scraping from turning into scratching.
- Re-soap and squeegee the pane. The final wash removes dissolver residue and leaves the glass uniform.
Tape, glue, and silicone: the steel wool stage
Quick answer: Tape residue and cured silicone come off with fine 0000-grade steel wool worked over soaped, wet glass. Used this way on standard uncoated panes, steel wool shears residue off without scratching, and it is an industry-standard tool for post-construction detailing. The scraper goes first on thick material and the wool finishes the surface.
Every window installer leaves a different autograph: tape corners, glue shadows, a thumb-drag of sealant near the frame bead, and none of it responds to soap. Our sequence on this building was scraper first for anything with thickness, then fine steel wool over wet, soaped glass for everything that remained.
Steel wool on glass sounds wrong to most people, and the caution is fair. The wool has to be fine grade, the glass wet and soaped, and the pane standard uncoated glass. Within those rules it shears glue and cured silicone off the surface without marking it, and professional window cleaning suppliers teach exactly this technique for construction debris. On dry glass or an exotic coating, the same wool means buying the client a new window, so post-construction work is no place for guesswork.
This job by the numbers
Quick answer: The Sumac Community Food Centre job came to $890 total: $800 for full inside-and-outside window cleaning of the 3-storey building, plus $90 for the skylights the client added once we flagged them. It took a 2-technician crew, 2 complete washes of the building, and a 16-foot ladder for the tallest interior glass.
| Item | Detail |
|---|---|
| Building | 3-storey commercial, heritage brick + new glazing, Toronto |
| Base price | $800 inside + outside, all windows |
| Skylights add-on | $90, client approved on-site |
| Crew | 2 technicians |
| Full washes performed | 2 complete passes of the building |
| Concrete dissolver dwell | 5 min per treated spot |
| Tallest interior access | 16-foot ladder, carried in |
| Coverage | $2M CGL + WSIB + Working at Heights certified |
Skylights and the 16-foot ladder
Quick answer: During the walkthrough we found skylights sitting beyond easy ladder reach, and interior glazing set high in the stairwell. The client added skylight cleaning for $90. For the tall interior panes, the crew carried a 16-foot ladder through the building and worked each pane from height.
On commercial buildings the hardest glass is often inside. Here it was a set of skylights and interior panes far above the stair landings. The skylights were not in the original scope. We found them and showed the client, who added skylight cleaning for $90 rather than leave dusty glass over the food centre's daylight.
The tall interior glass was a matter of logistics: a 16-foot ladder carried through finished rooms, set, climbed, moved and set again. Some exterior panes could only be reached from the steel fire-stair platforms on the addition, and that is where Working at Heights habits earn their keep.
Why we washed the building twice
Quick answer: With 2 construction sites operating next door, dust kept settling on finished windows while the crew worked the rest of the building. DT Cleaning ran a second complete pass over all the glass before handing the building back, 2 full washes for the one $800 price, because a community centre should not open behind someone else's dust.
Working beside active construction has one problem no method fixes: the site does not pause because you are cleaning. Panes we finished early had a fresh layer of dust by the time we circled back. It was thin, but it showed on the new black frames and tall clear glass, right at a visitor's eye level.
When the detailing was done, we went back to the start and washed the whole building again, top to bottom, at the same price. Some of that is pride and some is arithmetic: a commercial client who opens their doors behind clean glass calls the same company next season, and one who finds streaks on opening day does not.
"The site next door ran the whole time we worked. You either accept dust on finished glass or you wash the building twice. We washed it twice."
DT Cleaning crew lead, July 2026
What post construction window cleaning costs in Toronto
Quick answer: DT Cleaning prices post construction window cleaning in Toronto by glass area, residue level, and access: most residential projects run $300 to $800, and this 3-storey commercial building came to $890 including skylights. Concrete, tape, and silicone removal are included in the quote, not billed as surprises afterward.
| Project type | Typical range | What moves the price |
|---|---|---|
| Residential post-construction | $300-$800 | Window count, residue level, interior access |
| Commercial building, inside + outside | from $800 | Glass area, storeys, access equipment |
| Skylights add-on | from $90 | Count and reachability |
| This case study | $890 | 3-storey commercial, in + out, skylights, 2 full washes |
We price the residue as well as the glass. A pane with concrete and silicone on it takes several times the labour of a dusty pane, and a building beside an active site may need a second wash, as this one did. All of that goes into one flat number up front, as our post construction window cleaning service page describes. For buildings on a regular maintenance schedule, standard window cleaning in Toronto costs far less, because nobody is dissolving concrete.
When to book the glass clean on a construction project
Quick answer: Book post-construction window cleaning as the second-to-last trade: after painters, drywallers, masons, and window installers are fully done, but before furniture and signage go in. Cleaning glass while trades still generate dust means paying twice; on this Toronto job, 2 active sites next door forced a second full wash even with good timing.
For property managers and homeowners planning a build or renovation, the sequencing matters more than the product choice:
- Let every dust-making trade finish first. Concrete cutting, drywall sanding, and painting all end up on the glass. Glass cleaned too early gets dirtied on someone else's schedule.
- Settle the tape question before the crew arrives. If protective film or tape should stay on some windows, flag it. Everything else comes off.
- Walk the building for hidden glass. Look for skylights, stairwell panes and transoms above doors. Finding them during the quote beats finding them from a 16-foot ladder mid-job.
- Ask how the crew handles construction residue. If the answer is "soap and squeegee", you are buying a regular wash with a bigger invoice. A real post-construction service uses dissolvers, scrapers, and steel wool.
- Plan for neighbouring sites. If construction continues next door, discuss a second pass up front, or schedule the final clean after the neighbours top out.
We do this walkthrough on every commercial quote, the same way we scope multi-service residential visits like our North York luxury home cleaning before a 160-guest party or the paired window-and-eavestrough day in our Mississauga French-panel case study.
Key takeaways
Where we do this work
Post-construction and commercial window cleaning, priced the same way, across Toronto and the GTA:
Post construction window cleaning questions, answered
How do you clean glass windows after construction?
Flood the glass with water first so abrasive dust floats off, then wash with soap and a sleeve. Treat concrete spots with a dissolver, scrape residue off wet glass with a flat blade, and finish tape glue and silicone with fine steel wool on soaped glass. Squeegee and towel the edges dry.
How much does post construction window cleaning cost in Toronto?
DT Cleaning prices most residential post-construction projects at $300 to $800, depending on window count, residue level, and interior access. Commercial buildings start around $800 for inside-and-outside service; this 3-storey Toronto case study came to $890 including a $90 skylight add-on.
What is the difference between regular and post-construction window cleaning?
Regular cleaning removes dirt with soap, water, and a squeegee. Post-construction cleaning removes bonded residue: concrete splatter, installation tape glue, and cured silicone, using dissolvers, scrapers, and fine steel wool. A regular wash over construction residue leaves all of it on the glass.
How do you remove concrete from windows?
Apply a purpose-made concrete dissolver to each spot and let it work for about 5 minutes. Rinse away the softened material, then lift anything left with a metal scraper held flat against wet glass. Never scrape dry, untreated concrete; that is how panes get permanently scratched.
Does steel wool scratch glass?
Fine-grade steel wool used on wet, soaped, standard uncoated glass does not scratch; professional suppliers teach it for removing tape glue and cured silicone. It becomes risky on dry glass, tinted films, or specialty coatings, so identifying the glass type comes before the wool touches anything.
Why did the water-fed pole leave streaks on this building?
Two active construction sites next door kept the building dusted with fine debris. The pole's rinse water picked that dust up as it sheeted down and dried into a grey film with streaks on the frames. The crew abandoned the pole and hand-washed all glass by the sleeve-and-squeegee method.
When should windows be cleaned after construction?
After every dust-producing trade has finished: masonry, drywall sanding, painting, and window installation. Cleaning earlier means paying for glass that gets dirty again on the project's schedule. If construction continues on neighbouring lots, plan a second pass or schedule the final clean later.
Is construction dust harmful to windows?
Yes, in two ways. Much of it contains crystalline silica from cut concrete, which is abrasive: wiping it dry effectively sands the glass. It also contaminates rinse water, causing streaks. Panes should be flooded with water before any cloth or sleeve touches them.
Do you clean skylights as part of post-construction service?
Yes, as a scoped add-on, since skylights need their own access plan. On this Toronto commercial job the client added skylight cleaning for $90 after our walkthrough flagged them. Interior high glass was reached with a 16-foot ladder carried through the building.
Who does post construction window cleaning in Toronto?
Look for an insured company with WSIB coverage, Working at Heights certification, and an actual residue process: dissolvers, scrapers, and steel wool, not just soap. DT Cleaning provides post-construction window cleaning across Toronto and the GTA, backed by 500+ five-star Google reviews. Call (647) 558-8411.
How this case study was made: written with AI from DT Cleaning's own records of this job, the invoice figures and the photographs from the visit; the facts checked against those records before publishing.
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We do post-construction and commercial window cleaning across Toronto and the GTA. Concrete, tape, and silicone removal is included in the quote, and our crews are insured, WSIB-covered and Working at Heights certified.