What to Expect During Your Building's Waterproofing Works

If your building is about to start waterproofing remediation, this guide explains what's happening, how it affects your daily life, and what you need to do before the crews arrive.

How long the works take

Waterproofing remediation typically runs 8–14 weeks per area, depending on the scope and size. Full-building programs are staged so your disruption window is limited — you don't wait for the whole project to finish before getting your area back. Weather delays are common, because membranes need dry conditions.

Working hours are 7am to 5pm, Monday to Friday. Saturdays (8am–1pm) are only used for catch-up if the program needs it. No work happens on Sundays or public holidays.

The loudest period: the first 1–2 weeks

The demolition phase — jackhammering, grinding and power tools — is the noisiest part of the entire project. After demolition is complete, noise drops significantly for the remaining works. If you work from home, tell the site supervisor. You can get the specific demolition dates for your area so you can plan around them.

What changes during the works

• Noise and vibration. Loudest in the first one to two weeks of demolition. Vibration may be felt in adjacent units.
• Access equipment. Scaffolding or swing stages may wrap part or all of the building for the duration. This changes the building's appearance and can reduce natural light. Anchor tie marks are patched when it comes down.
• Your balcony or terrace is off-limits. The work area is completely closed for the duration. Finished areas are handed back progressively.
• Door removal. If your threshold is being waterproofed, your door comes out — for about 2 weeks if it's being reinstated, or 3–4 weeks if it's being replaced. A secure, weatherproof hoarding goes in the same day.
• Workers near your unit. Tradespeople work outside your windows and doors, and may need to enter your unit for access or inspections — always coordinated in advance.
• Dust. Concrete demolition creates dust. Sheeting and containment are used, but some can enter through gaps around doors and windows.
• Parking and access. Some car spaces may be temporarily unavailable, entry routes may change, and driveways may close briefly during crane lifts.
• Pets. Keep pets out of the work area and secure them in a closed room during door changeover. Noise-sensitive pets may need other arrangements during demolition.
• Furniture and plants. Everything must be removed from the work area before your start date. If something is too heavy to move, tell your strata manager early.
• Services. Water, hot water or gas may be briefly interrupted if services run through the work zone. You'll be notified in advance.

Door removal and temporary hoarding

Thresholds are one of the most common waterproofing failure points, so the door has to come out for the sill to be properly detailed. Here's how it runs:

1. Advance notice. You get at least 7 days' written notice before removal.
2. Door removed. The existing door is taken out and the opening is prepared for waterproofing.
3. Hoarding installed the same day. A solid, weatherproof, lockable panel is fitted — it blocks wind and rain and keeps your unit secure and private.
4. Threshold waterproofed. The sill is waterproofed, new flashings are installed, and the membrane is tied into the frame.
5. Door goes back in. A reinstated door returns once the threshold work has cured — typically around 2 weeks. A replacement door is fabricated to suit the new threshold detail — typically 3–4 weeks. The hoarding comes down the same day.

During this period your unit stays secure and weatherproof, but you lose natural light and airflow from that opening. If that creates hardship, tell your strata manager before works reach your unit.

The process, step by step

1. Strip and demolition. Tiles, pavers, screed and the old membrane are removed to expose the structural slab. The loudest phase — and the point where the work area closes completely.
2. Structural repairs. With the slab exposed, any cracking, spalling or reinforcement corrosion is repaired. If significant corrosion is found, this stage can extend the timeline.
3. Door removal and hoarding. The threshold is opened up for proper detailing, with the temporary hoarding installed the same day.
4. Membrane application. The new membrane goes on in multiple coats, with reinforcing at junctions and upturns. Each coat must cure before the next. Rain or cold means waiting rather than risking a failed membrane.
5. Flood testing. Before any finishes go back on, the area is filled with water and held while the areas below are checked for leaks. Any defect is repaired and retested. This is how the waterproofing is proven before it's covered up.
6. Finishes. Protective screed, then tiles, pavers or coatings per the engineer's specification. Drainage outlets and flashings are completed, and your door is reinstated once the threshold tiling and sealant are done.
7. Handover. Completed areas are handed back progressively with a final inspection, and the defects liability period begins.

Common questions from residents

Do I need to move out?

No. You stay in your unit throughout. During door removal, the hoarding keeps your unit secure and weatherproof.

Can I use my balcony during the works?

No — it's off-limits until handover. Walking on a curing membrane means redoing it.

What if it rains?

Membranes need dry conditions. Rain delays are common and may push your completion date.

Will the works damage anything inside my unit?

A dilapidation report is completed before starting. If damage occurs, report it to the site supervisor with a photo — any damage caused by the works is made good.

Who pays for the works?

The owners corporation funds the works through the capital works fund or a special levy. Individual owners aren't separately invoiced unless private lot areas are involved.

What happens after handover?

A defects liability period applies, plus the statutory warranty under NSW law. Report anything through your strata manager and the contractor returns at no cost.

Atomic Projects is a Sydney remedial building contractor and Class 2 registered practitioner under the DBP Act (builder licence 360636C), specialising in waterproofing remediation on occupied buildings. Questions? Call 0410 515 509 or email hello@atomicprojects.com.au.