Secondary Glazing Perth – Sound-Out Windows

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SoundOut secondary glazing — the most effective window solution we install

Across Perth homes, offices and heritage buildings, secondary glazing is the single most common thing we install. It sits on the inside of your existing window, no approvals needed, and it’s purpose-built to cut noise — not to keep heat in.

What secondary glazing actually is — in plain English

A SoundOut window is a second window installed on the inside of your existing one. You keep your existing window. We add a second pane in its own frame, set back into the reveal, and that creates an acoustic system:

• Your existing window is the primary barrier
• Our SoundOut window is the secondary barrier
• The air cavity between them is what does most of the work

The bigger the cavity, the better the noise reduction — with no change in glass thickness needed. In Western Australia, sitting the secondary window inside the existing reveal usually gives you a fantastic cavity depth and a great result.

Secondary glazing vs double glazing — what’s the actual difference?

People mix these up all the time. They’re different products built for different problems.

Double glazing was designed for thermal performance. It came out of cold-climate Europe and North America, where the priority is keeping heat in and cold out. It’s a full replacement window — your existing window is gone, double glazing goes in its place.

Secondary glazing (Sound-Out) was designed for noise. The system we use was developed by the New South Wales Government and Sydney Airport decades ago, drawing on European principles where people wanted to keep their existing windows rather than rip them out. It’s purpose-built for noise reduction, and it’s far more cost-effective than a full replacement.

If your problem is noise, secondary glazing is the right product. If your problem is heat loss in a cold climate, double glazing is the right product. In Perth, the problem is almost always noise.

What you can realistically expect

For normal levels of noise, we guarantee a 10 dB reduction over and above what your existing window is doing on its own. In a lot of jobs we exceed that significantly.

10 dB doesn’t sound like much until you understand what it means — it’s internationally recognised as a perceived halving of sound. Your brain registers it as “this is now quiet enough.” It’s the difference between being woken up at 5am and sleeping through.

The actual result depends on the type of noise (high-frequency traffic vs deep bass), the condition of your existing window, and any flanking paths around it. But the goal isn’t a number on a meter — it’s that you can sleep, work and relax in your own home again.

How the install actually works

Most installs sit inside your existing window reveal. That covers most mainstream Perth homes — brick veneer, project homes, apartments.

Where you’ve got a heritage timber window in good condition and there’s not enough depth in the reveal, we sometimes pull the architrave off and build the frame out, then refit to keep the original look. We can build out so plantation shutters can be reinstalled afterwards as well.

It’s a simple install in most situations. For heritage work we customise the install to keep the look right — and because secondary glazing keeps the original window visible from the outside, heritage bodies generally don’t have an issue with it. We’ve done a lot of heritage work across Perth and Fremantle, including the Waters Cottages in Fremantle, Freo Social, cottages on Queen Victoria Street, and the heritage-listed city building McKinsey & Company work from.

Working with different window types

We can accommodate almost any window type and size.

Fixed windows — we install a fixed inside panel. The results are actually superior because there are no operable joins in the frame to leak. We seal the existing window first to keep bugs and dust out.

Awning windows — we usually pair them with a double-hung secondary window. It’s not technically a SoundOut unit, but the cavity principle still applies and you get the noise reduction.

Standard sliding or double-hung — our Sound-Out window has both panels operable. Most secondary glazing on the market has one fixed and one active panel. Ours both move — so you can still access your existing window for cleaning, and you’ve got full ventilation control on either side of the unit.

Where we’ve installed Sound-Out windows across Perth

Plover Drive, Willetton — al fresco teenager noise

We installed Sound-Out windows in a bedroom next to an al fresco area where teenagers were keeping a toddler awake. Magnificent result — the room became usable again as a nursery.

Heritage cottages, Fremantle

Houses around the Burt Street / Queen Victoria Street precinct. Heritage windows kept intact externally, secondary glazing fitted internally, noise from the busy precinct reduced significantly.

Apartments, West Perth — train line noise

Multiple apartments near the train line. Secondary glazing cut the rumble and the brake squeal enough that residents could sleep through the early-morning services.

Apartments, Adelaide Terrace

Lots of apartments along Adelaide Terrace dealing with road and traffic noise from one of the busiest stretches in the city.

Apartments opposite RAC Arena

Event-night noise, late finishes, crowd noise after concerts. Secondary glazing brought the apartments back to liveable on event nights.

McKinsey & Company, Perth

Heritage-listed city building. Secondary glazing fitted internally without changing the external heritage appearance.

Why secondary glazing works so well in Perth

• Most homes here have single-glazed aluminium or timber windows that leak sound badly
• Road and aircraft noise is the dominant noise problem across Perth suburbs — exactly what secondary glazing was designed for
• No external change — important for heritage areas, strata properties, and rentals
• No approvals needed in most cases — the work is entirely internal
• Cost-effective compared to a full window replacement, especially across multiple windows
• Thermal benefit is still there — the frames don’t touch, so they’re essentially thermally broken

When secondary glazing isn’t the right answer

We won’t specify it for every job. Honestly:

• The noise isn’t coming through the window — sometimes the leak is the ceiling, the wall, an air-con vent, or a door. We’ll find the actual path before we quote.
• The existing window is in poor condition — if the frame is rotting or the seals are completely gone, sometimes a full replacement makes more sense.
• Internal echo and reverberation — secondary glazing blocks external noise; it doesn’t fix a bouncy hard-surface room. For that we use acoustic panels.

We’ll tell you straight if the job needs something else.

FAQ

How much does it cost?

Depends on the number of windows, the sizes, and the install conditions. We don’t quote blind — we’ll give you an accurate online price after we understand the job. As a guide, secondary glazing is typically a fraction of what a full double-glazing replacement costs.

Do I need approval from strata or council?

Generally no. The work is entirely on the inside of your existing window, so strata, heritage and council approvals are rarely required. Heritage bodies actually prefer secondary glazing because the original window stays visible externally.

Will I still be able to open my existing window?

Yes. Both panels of our SoundOut window move, so you can access your existing window for cleaning, and ventilate from either side as you like.

Will it affect my blinds or curtains?

We try to be minimalistic and work around your existing window treatments. In most cases your blinds, plantation shutters or curtains can be reinstalled or kept in place.

Can you do it in a rental?

Yes. Because the install is internal and can be removed cleanly if needed, secondary glazing works well in rentals where landlord approval is easier than for a full window replacement.

How long does it last?

It’s a permanent install. The frames, glass and seals don’t degrade or lose acoustic performance over time.