Apartment and strata flooring in NSW

Every year owners across Manly, Dee Why, Neutral Bay, Cremorne, North Sydney and Bondi install a floor, receive a complaint from the lot below, and discover their building had an acoustic requirement they were never told about. NCAT has ordered non-compliant floors removed at the owner’s cost.

It is entirely avoidable. The requirements are published, the approval pathway is set out in legislation, and the paperwork is straightforward once you know what is being asked for. We treat that as part of the job.

The two rules that apply to your floor

First, the National Construction Code. For a floor separating one apartment from another, NCC 2022 Part F7 requires impact sound insulation of L′nT,w ≤ 62 and airborne insulation of Rw + Ctr ≥ 50, determined under AS ISO 717.2. That is the legal floor, not a target.

Second — and this is the one that actually catches people — your building’s own by-law. Most NSW schemes set a stricter requirement than the Code, expressed as an AAAC star rating. The NSW model by-law on floor coverings requires an owner to ensure all floor space in the lot is covered or treated enough to prevent noise likely to disturb another lot, excluding the kitchen, laundry, lavatory and bathroom.

The approval pathway, in plain terms

Under section 110 of the Strata Schemes Management Act 2015 (NSW), removing carpet or other soft floor coverings to expose or install hard flooring is expressly prescribed as a minor renovation. That matters, because a minor renovation needs approval by ordinary resolution at a general meeting — not the special resolution and by-law that section 108 works require. Approval may be given subject to reasonable conditions, and it cannot be unreasonably withheld. Many schemes delegate the decision to the strata committee.

In practice this means a written application with the right attachments, and typically two to four weeks for a decision.

What schemes usually ask for

• An acoustic test report from an accredited laboratory, or a desktop assessment by an acoustic engineer, showing the proposed system meets the by-law and at minimum the NCC figures.
• The contractor’s public liability insurance certificate.
• Workers compensation cover.
• A quote or scope detailing the products and the areas involved.
• Often a SWMS, agreed work hours, and a plan for protecting lifts and common areas.

The honest part nobody puts on their website

Underlay ratings are laboratory figures, measured on a specific test slab with a specific build-up. Your building is not that slab. Concrete thickness, the ceiling treatment in the lot below, service penetrations and cavities all change the real result, sometimes substantially.

So a product rated 6 star in a lab is not automatically 6 star in your apartment, and only on-site testing after installation confirms actual performance. We say this out loud because being surprised by it later is expensive — and because a contractor who promises a lab number as an installed guarantee is telling you something they cannot know.

What we do

We check your by-law before specifying anything, propose a floor build-up with documented acoustic performance, and put together the application pack so you can submit it. Then we work to the building’s access rules, protect the common areas, and keep to the permitted hours.

At a glance