What to Expect During a Coating Project

Before the crew arrives

Notify tenants and building occupants 5 to 7 days before the project start date. A simple written notice explaining the work, the timeline, and what to expect is sufficient. Include the contractor's name and your contact information for questions. Let tenants know that the building will remain fully operational, that the loudest work happens on day one, and that subsequent days will have minimal noise.

Coordinate with the contractor on logistics. Identify where the crew should park (typically 2 to 4 spaces), where the equipment trailer will be positioned, and which roof access point they will use. If your building has a specific loading dock, service entrance, or restricted areas, communicate these before the crew mobilizes. The contractor should also confirm the weather forecast for the work week and identify any potential delay days.

Ensure roof access is clear and safe. Hatches should be unlocked. Ladder access points should be unobstructed. Rooftop HVAC equipment should be running normally (the crew works around it). Alert your HVAC service provider that roofing work will occur so they do not schedule maintenance visits during the coating project. Confirm that all rooftop antennas, solar panels, or other equipment are identified so the crew can protect them during application.

Day 1: Mobilization and pressure washing

The crew typically arrives between 6:30 and 7:30 AM and begins setting up equipment. Mobilization takes 1 to 2 hours — positioning the equipment trailer, running hoses and power lines to the roof, and staging materials. From the building interior, you may hear some activity on the roof during setup, but the noise level is comparable to normal foot traffic.

Pressure washing begins mid-morning and lasts 4 to 6 hours on a 20,000-square-foot roof. This is the loudest day of the project. The pressure washer generates 70 to 80 decibels on the roof surface, which translates to 50 to 65 decibels inside the building depending on ceiling construction. Inside, this sounds like a distant washing machine or a light rain on the roof. Conversations at normal volume are unaffected. Phone calls may require closing office doors in rooms directly below the work zone.

Water from pressure washing runs off the roof through the existing drainage system. The runoff carries dirt, algae, and debris. If your building has external downspouts that discharge onto sidewalks or landscaping, expect discolored runoff during the washing period. The contractor should position any ground-level equipment to avoid interfering with building entrances and walkways.

After washing, the roof must dry before any coating work can proceed. The crew may use the remaining afternoon hours to begin setup for the next day's repair work. In humid Gulf Coast conditions, the roof may not be completely dry until the following morning, which is why Day 2 starts with repairs rather than coating application.

Day 2: Repairs and priming

Day 2 is a quiet day — the work involves hand repairs to seams, flashings, and penetrations. Noise from the roof is minimal: hand tools, occasional caulk gun use, and crew conversation. Inside the building, Day 2 is nearly indistinguishable from a normal day. Tenants who were concerned about noise on Day 1 will be relieved to find that the rest of the project is significantly quieter.

The repair crew works systematically across the roof following the survey-identified deficiency list. Open seams are re-sealed. Deteriorated flashing is repaired or replaced. Pipe boots and penetration seals are replaced as needed. Any wet insulation sections identified in the survey are cut out and replaced with new insulation, and the membrane is patched over the repair.

After repairs are complete, the crew applies primer to any areas that require it. Priming is a quick process — typically 1 to 2 hours for a 20,000-square-foot roof. The primer must dry before coating application, which usually happens overnight. By the end of Day 2, the roof is fully prepared and primed, ready for coating application the following morning.

Day 3: First coat application

The spray crew arrives early — coating application should begin as early in the morning as conditions allow. On the Gulf Coast, the optimal window starts when morning dew has evaporated and the surface temperature reaches the minimum for the coating chemistry (40 degrees Fahrenheit for silicone, 50 degrees for acrylic). During spring and fall, this is typically 8:00 to 9:00 AM. During summer, application can begin by 7:30 AM.

The airless sprayer produces a steady humming noise at 55 to 65 decibels on the roof. Inside the building, this translates to 35 to 50 decibels — similar to the ambient noise of an air-conditioned office. Most building occupants will not notice the coating application is happening. The spray equipment moves across the roof at a steady pace, covering 4,000 to 6,000 square feet per hour with a crew of 3 to 4 applicators.

A 20,000-square-foot roof typically receives its first coat in 4 to 6 hours. The detail crew follows behind the spray crew, applying additional coating with rollers at all penetrations, flashings, and perimeter edges. Reinforcing fabric is embedded in the first coat at these detail locations. By mid-afternoon, the first coat is complete and curing.

The first coat requires 8 to 24 hours of cure time before the second coat can be applied. In ideal conditions (warm, moderate humidity), silicone may be ready for the second coat the following morning. In high-humidity Gulf Coast conditions, the cure may extend to late the following morning. The contractor checks the coating at multiple points — the surface should be dry to the touch and firm enough to walk on without leaving footprints.

Day 4: Second coat application

Day 4 follows the same pattern as Day 3, with the second coat applied perpendicular to the first. Applying the second coat at a 90-degree angle to the first ensures that any thin spots or holidays in the first coat are covered by the second pass. The spray crew covers the same area, at the same rate, with the same equipment. The detail crew follows with roller application at all transitions.

The contractor should take wet film thickness readings during Day 4 application to verify the specification is being met. Ask the contractor or foreman if they are taking WFT readings. If they are, ask to see the reading log at the end of the day. These readings provide real-time quality assurance — if the coating is being applied too thin, the applicator can adjust the spray rate immediately rather than discovering the deficiency after the fact.

By mid-afternoon, the second coat is complete and curing. The roof now has its full specified coating system — two coats of the selected chemistry at the target thickness. The coating requires 24 to 48 hours of cure time to reach its full hardness and performance characteristics. During this cure period, the roof is functional (waterproof) but should not be walked on or subjected to equipment placement.

Day 5: Inspection and punch list

The final day is dedicated to quality verification and correcting any deficiencies. The contractor walks the entire roof checking for holidays, thin spots, incomplete detail work, blisters, and any areas that need touch-up. Dry film thickness readings are taken at multiple locations to confirm the specification was met. Any deficient areas are recoated.

This is your opportunity to walk the roof with the contractor and see the completed work. Ask to see the thickness readings. Ask about any areas that required touch-up. Check the detail work at a few penetrations and flashings — the reinforcing fabric should be fully embedded and not visible through the finished coating. Take your own photos of the completed work for your building records.

Equipment is demobilized during the afternoon — the trailer is loaded, hoses are removed, and the crew parking spaces are returned. By the end of Day 5, the project is physically complete. The contractor should provide or schedule delivery of the documentation package: photos, thickness readings, material usage records, and warranty information. Final payment (less any retention amount) is due upon satisfactory completion and documentation delivery.

Impact on your business operations

The honest summary: most building occupants do not realize a coating project is happening until someone tells them. The noise profile is substantially below the level that interrupts office work, medical appointments, retail activity, or classroom instruction. There is no tear-off noise, no impact fastening, no interior weather exposure, and no parking lot staging that restricts customer access.

The one exception is Day 1 pressure washing, which is audible inside the building. Even this is far below the disruption threshold for most businesses — it sounds like distant mechanical noise, not like construction overhead. For noise-sensitive operations (recording studios, hearing test facilities, sound-critical environments), schedule the pressure washing for a time when the sensitive operation is not active — early morning, weekend, or a scheduled closure day.

No interior access is needed at any point during the project. The crew works entirely on the roof. They access the roof via exterior ladder, hatch, or designated access point. They do not need to enter office suites, retail spaces, or common areas. The only exception is if the contractor needs to inspect the underside of the deck from inside the building, which takes 15 to 30 minutes and can be scheduled around tenant operations.

What happens when weather interrupts

Rain during the project stops the coating work but does not create an emergency. The existing membrane beneath the coating continues providing waterproofing throughout the project. Partially cured coating (more than 4 hours old for silicone) is unaffected by rain. The crew covers uncured work, parks the spray equipment, and waits for dry conditions. Work resumes when the surface is dry — typically the following morning after a rain day.

Each rain day adds one day to the project timeline. A 5-day project that encounters 2 rain days becomes a 7-day project. The contractor should communicate schedule adjustments promptly — by the end of the rain day, they should confirm the expected restart date with you. There is no additional cost for weather delays unless the contract specifically charges for standby time (uncommon for coating projects).

On the Gulf Coast, plan for at least 1 to 2 weather interruption days during any coating project. If the project is scheduled during the summer thunderstorm season (June through September), plan for 2 to 3 interruption days. The contractor should check the 10-day forecast before starting and identify the optimal consecutive dry-day window. Starting the project on a Monday with clear weather through Friday is ideal — starting on Thursday with rain forecast for Friday creates an awkward split.

After the project is complete

The coating reaches its full performance within 48 to 72 hours after the final coat. During this period, avoid walking on the roof and do not allow rooftop HVAC service until the coating has fully cured. After 72 hours, the roof can be walked on normally and all rooftop maintenance activities can resume.

Schedule an annual inspection to maintain the coating system and preserve warranty coverage. Annual inspections check for debris accumulation around drains, mechanical damage from foot traffic or equipment service, sealant condition at penetrations, and any localized coating deterioration. Minor maintenance — clearing drains, patching small damage, touching up scuffs — extends the coating's effective lifespan and is typically required by the warranty to maintain coverage.

Keep the project documentation package accessible for future reference. The thickness readings, material records, and warranty documents will be needed for insurance claims, property sales, future re-coating decisions, and any warranty claims. Store a digital copy in your building management files and a physical copy in the building's permanent records.

Your next major decision point comes at approximately 75% of the coating's expected lifespan. For a silicone system with a 12-year expected life, schedule a professional re-assessment at year 9. This assessment evaluates the coating's remaining condition and determines whether maintenance, spot recoating, or full recoating is needed to maintain waterproofing through to the end of the expected cycle. Planning ahead prevents the surprise of discovering the coating has worn through. Call (251) 250-2255 to schedule your initial assessment or annual inspection.