Article Highlights

• Gas struts provide smooth, safe and effortless operation for larger windows, making them ideal for kitchens, servery windows and alfresco spaces.
• Accurate measuring is essential—check the extended length, diameters, end fittings and Newton force rating before ordering a replacement.
• Perth’s coastal climate requires durable materials, with stainless steel or corrosion-resistant gas struts offering better long-term performance.
• Replace worn gas struts promptly and always in pairs to maintain safe operation, balanced support and protect your window hardware.

Gas struts may be small, but they play a big role in how easily and safely windows and doors open and close. In windows, they help lift and hold the sash in place, making larger openings much easier to operate without heavy lifting or awkward manual support.

For Perth homes, gas strut windows are especially popular in kitchens, alfresco areas and servery-style openings, where smooth operation and a clear indoor-outdoor connection matter. In this guide, we explain how gas struts work, how to measure them correctly, what to consider for Perth’s climate and when worn struts should be replaced for safety.

How do Gas struts Work?

A gas strut is a sealed cylinder filled with high-pressure nitrogen gas and a small amount of oil. Inside the cylinder sits a piston attached to a rod. When you push the rod in, it compresses the gas. When you release it, the pressure pushes the rod back out, creating a controlled lifting or supporting force.

That’s really it. No motors, no springs, no complicated mechanics. The result is smooth, controlled movement that lets a door close gently or supports a window in the open position without slamming.

The force is measured in Newtons (N) and is typically printed directly on the strut label. A figure like “400 N” indicates the pushing force the strut generates when fully extended. We expand on this below.

Gas Struts in Perth Windows

Gas strut windows use pressurised gas-filled struts to help lift, hold and lower the window sash with ease. When the window is opened, the gas struts extend and support the weight of the glass or frame, allowing it to stay securely in position without needing extra brackets or manual support.

This makes the window easier and safer to operate, especially for larger awning, servery or pass-through windows. The struts also help create a smooth, controlled opening and closing motion, reducing strain on the hinges and making the window more practical for everyday use.

How to Measure a Gas Strut

Getting the measurements right before you order is the most important step. An incorrect size means the strut either won’t fit or won’t perform as expected. Here’s how to measure a gas strut correctly:

Step 1 – Measure the extended length

With the strut fully extended, measure pin-centre to pin-centre (that is, from the middle of one mounting point to the middle of the other). This is your extended length. Allow a tolerance of around ±2 mm.

Step 2 – Measure diameters

While extended, measure the diameters of both the inner rod and the outer canister that holds the rod. Make sure you are getting the measurement to the millimetre.

Step 3 – Check the end fittings

Look at both ends of the strut. Common end fitting types include 6 mm or 8 mm ball joints, eyelets, and threaded studs. Note the type and size at each end, as these need to match your mounting points.

Step 4 – Read the force rating

The force rating in Newtons is usually printed on the strut body. If you’re replacing an existing gas strut, aim to match or slightly exceed the original force rating. Never fit a weaker strut, as this creates a safety risk.

Choosing End Fittings and Materials for Perth Conditions

Perth’s coastal suburbs, from Cottesloe through to Rockingham and Mandurah, are exposed to salt air that accelerates corrosion of standard steel components. For any outdoor or near-coastal application, stainless-steel or epoxy-coated strut bodies are a sensible choice. The rubber seals around the rod are also vulnerable to UV degradation, which Perth’s high UV levels will speed up over time.

For indoor applications like kitchen cabinetry, standard zinc-plated struts are generally fine. But for alfresco areas, outdoor storage, or any window hardware exposed to the elements, it’s worth specifying a corrosion-resistant finish.

When a Worn Gas Strut Becomes a Safety Issue

Gas struts don’t last forever. They typically lose around 1% of their force each year, which means a strut that was perfectly calibrated a decade ago may now be noticeably weaker. A strut that’s lost too much pressure won’t hold a lid or window open reliably, and that’s when things can become dangerous.

A few signs it’s time to replace your struts:

• Your gas strut window drops more slowly than it used to, or doesn’t stay fully open
• You can hear or feel a difference in resistance compared to when it was new
• The rod shows signs of corrosion, pitting, or oil leakage around the seal

Always replace gas struts in pairs. If one is worn, the other is likely close behind, and the mismatched forces between the two struts create uneven loading on the frame.

For windows and doors that need more than just a strut swap, our door repairs and servicing team can assess the full setup and recommend the right approach.

How Gas Struts Elevate Window Design

Gas struts can transform your outdoor alfresco area into an open, breezy oasis with just a push. The gas strut does all the heavy lifting, so you can create an unobstructed bar between your indoor kitchen and outdoor patio with minimal physical effort.

Perth Window & Door Replacement Company has been supplying and installing gas strut windows and doors across Perth for over 40 years. Our team is familiar with the specific demands of Perth’s climate and can help you identify the right strut for your windows. Get in touch with us directly, and we’ll point you in the right direction.

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