Quick answer
The best setup for a composite door pairs a TS007 3-star anti-snap euro cylinder with a multi-point gearbox that matches the door manufacturer's original brand and hook pattern. Mixing an unrelated cylinder brand with an unrelated gearbox is the most common cause of poor-fitting, unreliable locks we're called out to fix.
Overview
For the cylinder: any TS007 3-star (Avocet ABS, Ultion, Yale Platinum). For the gearbox: match the brand of your door (Winkhaus AV2, Fuhr, ERA Vectis, Yale Lockmaster). Mixing brands is asking for trouble.
Cylinder first: this is where the money should go
If you only upgrade one component on an existing composite door, make it the cylinder. TS007 is the British Standards Institution kitemark scheme rating anti-snap, anti-pick, anti-drill and anti-bump performance from 1 to 3 stars. A 3-star cylinder on its own, or a 1-star cylinder combined with a 2-star security handle (the two ratings add together), meets the standard most insurers and locksmiths now recommend as a minimum.
Popular options fitted across the trade include Avocet ABS, Yale Platinum and Ultion, among others. All three have a solid track record; the right choice for a given door often comes down to exact sizing rather than brand loyalty; get the length wrong by even a few millimetres and you reintroduce the snapping vulnerability you were trying to eliminate.
Gearbox brands: why matching matters
The multi-point mechanism running down the door edge - the gearbox, hooks, bolts and drive bar - is usually one of a handful of major brands: Winkhaus, Fuhr, ERA Vectis, Yale Lockmaster or GU. Each has its own hook spacing, faceplate dimensions and drive mechanism. Fitting a generic replacement rather than matching the existing brand often results in a mechanism that technically fits the mortice but doesn't sit quite right in the keeps, leading to stiffness or partial engagement within months.
Reading the brand stamped on the faceplate (visible when the door is open) before ordering parts avoids a wasted first visit and a second call-out.
Handles as part of the security picture, not just cosmetic
A 2-star security handle adds real resistance to snapping and drilling attacks aimed at the spindle rather than the cylinder itself. On an older door where you're not planning a full mechanism replacement, upgrading the handle alongside the cylinder is a cost-effective way to close a second attack route for relatively little extra labour, since both components come off together.
What we specify as standard on new fits
On new composite door installations across Cornwall we specify a TS007 3-star cylinder and a branded 5 or 7-point mechanism as standard, not an optional extra. It typically adds a small amount to the overall door cost against a security improvement that's disproportionately large.
- TS007 3-star euro cylinder as standard, not optional
- Branded multi-point mechanism matched to door manufacturer
- 2-star handle where budget allows, for belt-and-braces spindle protection
Retrofitting locks onto an older composite door
Most composite doors from the last fifteen years can accept a modern 3-star cylinder without any modification, since euro cylinder dimensions are a long-standing industry standard - it's simply a case of measuring the external and internal lengths correctly. Gearbox replacement is a little more involved because of the brand-matching issue above, but is still very much a retrofit job rather than something that requires a new door.
A note on high-security and holiday-let properties
For holiday lets, particularly those changing guests weekly, a higher-security cylinder like Ultion or an equivalent anti-snap, anti-bump product with keyed-alike options across multiple doors can simplify key management without compromising security, and its resistance to bumping is a genuine advantage where keys pass through many hands over a season.
Typical repair costs in Cornwall
| Work | Typical price | Notes |
|---|---|---|
| TS007 3-star cylinder, supplied and fitted | £75-£130 | Includes correct sizing survey |
| 2-star security handle upgrade | £60-£100 | Fitted alongside cylinder for combined saving |
| Branded multi-point gearbox replacement | £180-£320 | Price varies by brand and hook count |
| High-security cylinder (e.g. Ultion-tier) | £120-£180 | Popular for holiday lets and high-risk locations |
Guide prices only — we confirm the cost after seeing the door.
When to call a professional
- For gearbox replacement - sizing and handing matter.
Prevention
- Service annually to extend gearbox life.
