Friction Hinge Buying Guide: Side Hung vs Top Hung

Friction Hinge Buying Guide: Side Hung vs Top Hung

Choosing the right friction hinge for a window affects operation, security and longevity. This guide explains the differences between side hung and top hung friction hinges, practical selection criteria, fitting and maintenance tips for both trade professionals and confident DIY homeowners in the UK.

What is a friction hinge?

A friction hinge is a window hinge that uses adjustable friction or torque to hold the sash at any angle without the need for a stay. It allows controlled opening and prevents the sash from blowing shut or slamming fully open. Friction hinges are widely used on PVCu, aluminium and timber casement windows and are available in a range of torque ratings and arm configurations to match sash size and weight.

Side hung vs top hung: key differences

Understanding the fundamental differences will help you choose the right hinge for the application:

• Side hung: Hinged at the vertical side of the sash; sash opens outwards like a door. Common for traditional casements and offers good egress and ventilation. Side hung friction hinges often include variable torque to suit different sash weights.
• Top hung: Hinged at the top of the sash; sash tilts outward from the top to form an awning. Top hung friction hinges give weather protection and are useful where an overhung opening is desired; however, they can be less suitable for means of escape because the opening sits high.

When to specify side hung friction hinges

Choose side hung when the priority is full opening, easy cleaning and simple egress. Suitable applications include:

• Ground floor and upper-floor rooms where fire escape or easy exit is required.
• Sashes that need a wide clear opening for access or furniture movement.
• Timber and aluminium casements where traditional appearance and hardware compatibility matter.

Trade tip: For larger side-hung sashes use a friction hinge with a higher torque rating and consider using three hinges for very tall or heavy sashes to distribute load and reduce sash distortion.

When to specify top hung friction hinges

Top hung friction hinges are ideal where weather protection during ventilation is important, and where a high-set sash can still provide air flow without letting rain in. Typical uses:

• Bathrooms and kitchens where an awning-style opening protects against rain.
• High-level windows where full egress is not required.
• Where outward obstructions below the sill make side opening impractical.

Trade note: top-hung windows should be specified carefully for escape routes; they may not meet means of escape requirements unless combined with other escape provisions.

Selection criteria: what to consider

Match hinge specification to the sash and the building needs. Key factors to check:

• Sash weight and size: Always consult manufacturer torque charts; friction hinges are rated in Newton metres (Nm) and you must select a hinge that can support the sash weight while providing appropriate friction.
• Material compatibility: Choose stainless steel or corrosion-resistant finishes for coastal locations; zinc-plated may be acceptable for inland but check warranty.
• Number of hinges: Common practice: two hinges for small to medium sashes, three for larger or heavier sashes; follow manufacturer guidance for spacing and load distribution.
• Spigot and arm dimensions: Ensure the spigot diameter and arm length match the frame and rebated detail; mismatched parts cause poor operation and premature wear.
• Left/right handed: Many friction hinges are reversible; verify handedness before ordering replacements.
• Regulatory requirements: Check Building Regulations relating to means of escape and Document M for accessibility; certain rooms require specific opening sizes and hardware that allows quick release.

Practical fitting and replacement advice

Whether fitting new windows or replacing a worn hinge, follow these practical steps:

• Measure the sash weight and dimensions first; check the existing hinge for part numbers and spigot sizes where possible.
• Remove paint or obstructions from hinge mounting areas so the hinge sits square; paint on the pivot can alter friction and cause binding.
• Use appropriate fixings: self-tapping screws for timber frames, machine screws into steel reinforcement for PVCu; never rely on thin plastic skins alone.
• Align hinges squarely before fully tightening fixings; small misalignment leads to rubbing and accelerated wear.
• Adjust friction using the adjustment screw or slot system recommended by the manufacturer; start with lower friction and increase until the sash holds steady under wind loads.
• If replacing a damaged hinge, replace both hinges on the same side if they have equal wear; mismatched friction can cause twisting.

Maintenance and troubleshooting

Regular maintenance extends hardware life and keeps windows operating smoothly:

• Clean pivot areas and remove grit; lubricate pivot points annually with a light machine oil; avoid heavy greases that attract dust.
• Check for play in the pivot and replace worn hinges before they damage the frame or sash.
• If the sash droops or binds, check for loose frame fixings and adjustment screws; re-torquing and re-alignment often fixes the issue.
• For windows that do not hold position, verify the hinge torque setting and inspect for wear in the friction surfaces; replacement may be required if adjustment no longer helps.

Stocking and ordering tips for professionals

For trade suppliers or installers, keep a core range in stock to cover most jobs:

• Common torque-rated friction hinges suitable for small, medium and large sashes.
• Left and right configurations and reversible kits.
• Stainless finishes and coastal-grade variants for durability.
• Complete kits including keeps and screws for simple repeat fit-outs.

Always cross-reference manufacturer codes and keep technical datasheets to hand at the point of sale or on site; customers benefit from quick access to torque charts and fitting templates.

Further reading and resources

For a deeper look at hinge types, leg lengths and compatibility with different frame systems consult our pillar resource: /guides/window-hinges. Manufacturer installation sheets and torque tables are essential when specifying the right friction hinge for an unusual sash geometry.

Recommended Products

Based on this article, you may find these products helpful:

• Top-Hung Window Hinge - Standard
• Side-Hung Window Hinge - Standard
• Top Hung Friction Stay - 12"
• Side Hung Butt Hinge - 4"
• Flag Door Hinge - Stainless Steel

Conclusion and next steps

Choosing between side hung and top hung friction hinges comes down to function: side hung for full access and escape; top hung for weather-protected ventilation. Match hinge torque to sash weight, verify fixings and materials for the environment, and carry out correct alignment and maintenance to avoid operational issues. Next steps: weigh and measure your sash, consult manufacturers' torque charts, and either order the appropriate hinge or contact a qualified installer if escape or compliance questions apply.