How to Tell Which Window Hinge You Need

Determining how to tell which window hinge you need starts with understanding your window’s design and the hinge’s role in its operation. Window hinges, often called friction stays in modern uPVC casement windows, control opening angles and provide stability. Identifying the right replacement ensures smooth function without compromising safety.

This guide focuses on common uPVC friction stay hinges found in outward-opening casement windows. It covers essential measurements like friction stay size, stack height, track width and handed hinges. Always prioritise safety—avoid forcing components or working at height without proper equipment.

Why Accurate Hinge Identification Matters

Worn or broken window hinges can lead to sagging, poor friction or failure to stay open. Choosing the wrong replacement causes misalignment, draughts or security risks. Correct identification prevents repeated purchases and ensures compatibility with your window frame.

Matching hinges restores proper operation, maintaining energy efficiency in double-glazed units. Incorrect fits may stress locks or handles, leading to further repairs. For window hinge repairs, professional assessment follows identification.

Types of Window Hinges for uPVC Casement Windows

uPVC windows typically use friction stay hinges on the top and bottom for side-opening sashes. These differ from older hook-on or side arm hinges but share similar measurement principles.

Friction Stay Hinges

Friction stays are the most common, adjustable for tension to hold windows at various angles. They slide along a track, with size denoted by arm length (e.g., 305mm or 12 inches). See our parts/window-hinges/ range for examples.

Other Variations

Rarely, you might encounter offset or articulated stays, but stick to standard friction types for most post-2000 uPVC windows. Excluded types like tilt-and-turn or inward-opening hinges require specialist knowledge—consult a professional.

Key Measurements to Identify Your Hinge

To specify the correct hinge, measure three critical dimensions: stack height, track width and overall friction stay size. Handedness (left or right) is also vital for proper installation.

Stack Height

Stack height is the closed distance from the frame edge to the outer track edge. Common sizes are 13mm or 19mm—measure precisely with a ruler or caliper.

• Open the window fully.
• Measure vertically from the frame’s outer stile to the track’s end.
• Note: Mismatched stack height prevents flush closing.

Track Width

Track width spans the horizontal length of the sliding rail on the frame. Typical widths are 305mm (12”) or 406mm (16”).

• Use a tape measure along the track.
• Account for any wear that shortens effective length.
• Cross-reference with friction stay size charts.

Friction Stay Size

This refers to the arm length from knuckle to end cap, usually in inches (10”, 12”, 16”). Extended arms suit larger sashes.

Handed Hinges Explained

Handedness determines if the hinge is left-handed (for right-side opening windows) or right-handed (left-side). Viewed from inside:

• Top hinge: Arm bends towards hingeside when open.
• Bottom hinge: Mirror image for balance.

Test by opening—if the stay pulls towards the hinge side, note left/right accordingly.

Tools You’ll Need for Safe Identification

Gather these basics before starting:

• Digital caliper or steel ruler (0-150mm accuracy).
• Tape measure (at least 1m).
• Step ladder (stable, with handrails).
• Torch for shadows in tracks.
• Notebook for sketches.

Work during daylight, with a helper if possible. Never lean out unsupported.

Step-by-Step Guide to Identifying Your Window Hinge

Follow these steps methodically. Stop if anything feels loose or damaged—contact us for advice.

Step 1: Visual Inspection

Examine both top and bottom hinges for stamps (e.g., “12L” for 12-inch left). Clean debris first. Note material—zinc die-cast is standard.

Step 2: Safety Preparation

Secure the sash open with a prop. Disconnect handles if adjustable. For upper hinges, use a ladder indoors.

Step 3: Measure Stack Height

Close the window. From frame exterior, measure stack height on both hinges—tops and bottoms should match.

Step 4: Check Track Width

Open sash 90 degrees. Slide stay fully extended; measure track end-to-end. Compare to arm length.

Step 5: Determine Handedness

Open fully. View from inside: if stay arm is on the left when facing open sash, it’s left-handed (top view). Confirm bottom mirrors top.

Step 6: Note Additional Features

Check for restrictors, micro-ventilation holes or offset pivots. Photograph everything, including serial numbers.

Step 7: Cross-Check Compatibility

Use measurements against supplier charts. If unsure, browse parts/friction-stays/ for visuals.

Common Mistakes and How to Avoid Them

Misidentifying hinges wastes time and money. Here’s what to watch for:

• Confusing stack height with arm length: Always measure closed stack first.
• Ignoring handedness: Results in reversed operation—double-check viewing angle.
• Overlooking wear: Expanded tracks from rust shorten effective track width.
• Assuming symmetry: Top/bottom may differ slightly in older installs.

Rely on multiple measurements. If discrepancies arise, it’s often frame distortion needing pro adjustment.

When to Seek Professional Help

DIY identification suits minor checks, but replacement involves precise alignment and lubrication. Faulty hinges link to lock failures or misted units—better fixed together.

Signs for experts:

• Sash drops despite correct size.
• Multi-point locks bind.
• Frame warping evident.

For window hinge friction stay replacement, book a specialist. Explore more in our guides/ or contact us directly.

FAQ

What is the most common friction stay size for uPVC windows?

12-inch (305mm) suits most standard sashes up to 1200mm high, paired with 13mm stack height.

How do I know if my hinge is left or right-handed?

Open the window fully and view from inside—the stay arm position relative to the hinge side determines it.

Can I measure hinges without removing them?

Yes, all steps here use non-destructive methods. Removal risks frame damage.

Do all uPVC windows use the same hinges?

No, variations exist by manufacturer (e.g., Rehau vs. Deceuninck), but measurements standardise most.

What if my measurements don’t match standard sizes?

Likely wear or custom frames—consult a pro via contact/.

This guide equips you to identify hinges accurately. For parts, check window hinges. Professional fitting ensures longevity—reach out anytime.