Rim nightlatch (surface-mounted)

A surface-mounted case on the inside of the door with a cylinder through the door face. Pulling the inside knob retracts the latch; the outside is key-only. Universally fitted, cheap, and mechanically simple — but the case geometry varies more than any other family.

✓ verified · Where you will meet this lock: United Kingdom, Ireland, Australia, New Zealand, Southeast Asia

Also called: Yale lock · Night latch · Rim lock

⚡ 30-Second Retrofit Fit Check
3-Step Pre-Flight Verification to Prevent 90% of Stalls
1. Does door thickness and bore match standard mechanical specs?
2. Can original physical key operate smoothly from outside?
3. Is there sufficient indoor clearance for retrofit enclosure?
✓ Compliant with Global Retrofit Smart Lock Engineering Standards
⚙️ Operating Torque: 0.20 – 0.50 N·m (Nominal)
See installation diagrams and adapter specs below

Installation Photos & Retrofit Diagrams

Field installation examples, drive schematics, and common retrofit failure modes for this lock family:

⌖ Specialty & High-Security 4 models

EU-28

Italian Electric Rim Lock — CISA 11610 Style

R1
Engineering Specifications & Installation Field Photo · Blueprint

📷 Real Field Door Installation Case

Italian Electric Rim Lock — CISA 11610 Style Real Field Installation

Engineering field note: EU-28 mechanism verification & retrofit compliance.

📐 1:1 Blueprint & Drilling Template

Italian Electric Rim Lock — CISA 11610 Style Schematic & Template Blueprint

Includes backset, mortise pocket depth & spindle concentricity

🛠️ Tier 3: Standard Retrofit Installation Workflow
  1. Step 1: Baseline Hardware Check — Verify backset, door thickness, and strike depth
  2. Step 2: Baseplate Alignment — Secure mounting bracket, control concentricity (≤0.5mm)
  3. Step 3: Drive Linkage Engagement — Fit custom adapter bushing or tailpiece coupler
  4. Step 4: Door Close & Latch Cycle Test — Verify gap clearance and weatherstrip compression
📐 Recommended Clearance: ≥ 3.0mm (Door to Frame Gap) ⚡ Required Stall Torque: ≥ 1.2 N·m (Motor torque) 📄 Drilling Template ID: TPL-EUROPE5-EU-28
🔬 Engineering Tolerance & Compliance Matrix Grade B- (Semi-retrofit / Minor Screw Replacement)
Vertical Sagging Tol.:
±3.0mm
Weatherstrip Swelling:
≤2.5mm
Rated Stall Torque:
≥2.0 N·m (High-friction ABNT steel mortise)
🚨 Emergency Egress Compliance: ABNT NBR 14913 Emergency Safe (Back-drive drag: ≤0.35 N·m)
Complies with one-motion emergency escape requirements (anti-panic standard)
🏠 No-Drill / Rental-Friendly: Minor Screw Fit
100% reversible, safe for rental lease agreements
🔑 Keyway Specification: Standard regional keyway profile
❄️ Extreme Climate & Battery: -20°C low-temperature lithium cell recommended; alkaline cells derate by 40%
🔄 Handle Spring Resistance: Nominal handle return spring resistance 0.35 - 0.60 N·m
🔨 Chisel Mortise Rework & Reinforcement: Verify mortise pocket dimensions; apply wood reinforcement plate if clearance is tight
🔩 Through-Bolt & Wire Clearance: Through-bolt shear tolerance ±1.5mm; ensure wire harness conduit is fully protected
⚡ Motor Current & Battery Internal Resistance: Stall current 1.8A max; internal battery resistance threshold <120mΩ
🛡️ Security & Insurance Rating: Certified attack-resistant security standard
🧲 Door Sensor Gap & Metal Shielding: Magnetic gap threshold ≤15mm; anti-ferromagnetic shielding bracket required on steel doors
🏙️ Metropolitan Distribution: Paris · Berlin · Frankfurt · Madrid · Vienna
⚙️ Gearbox Ratio & Back-Drive Torque: Recommended gear reduction ratio 120:1 to 180:1; planetary metal gearbox
📏 Shear Line Clearance & Depth: Clearance ≤1.0mm; thumbturn adapter recessed 5mm, dual pinch travel 2.5mm
🎯 Nuki Retrofit & ICP Profile: ★ Fit Score: 96/100 · Urban condo tenants & apartment owners
🔑 Tenant Zero-Damage Grade: Grade A- (No-drill cylinder clamp & slim gate safe) · Est. Install: 3 mins
🛠️ Recommended Retrofit Kit: ADP-06 + ADP-01
☀️ Salt Spray & Weatherproofing: ASTM B117 / EN 1670 Grade 4 Corrosion Resistance · IP54
🌡️ Thermal & Gasket: -40°C ~ +60°C · Flame-retardant anti-fungal EPDM silicone weatherseal gasket
🔄 Multipoint Kinematics & Torque: Lift Angle: 45° Upward handle stroke · Drive Torque: Drive resistance 0.35 - 0.60 N·m
🔧 Hardware Vendors & Tuning: Winkhaus autoLock, GU-Secury, KFV/Siegenia · Adjust eccentric strike plate cams using hex key to reduce latch binding
⚠️ Emergency Dual-Clutch Approved List: DIN 18252 BS / EN 1303 Class 6 Emergency Clutch
Approved Clutch Cylinders: ABUS Bravus 1000 / 2000 / 4000 MX ( Not- und Gefahrenfunktion) · EVVA 4KS / EPS / ICS ( BS ) · Bricard Chifral S2 (Série 70 ) · ISEO R6 Plus
CRITICAL: Never install retrofit motor over a non-emergency clutch cylinder. A dead battery or motor jam will permanently lock out occupants.
🚪 Door Thickness & Fasteners: Nominal Door: 40mm ~ 65mm ()
🔩 Spindle & Bolt Spec: Spindle: 8mm square spindle bar · Bolts: M5 through-bolts cut-to-length based on door thickness
🛡️ Reinforcement: Architectural stainless steel reinforcement escutcheon plate
⚙️ Retrofit Engineering & Resistance Notes

Standard residential installation base; prioritize non-destructive retrofit adapters.

Minimum physical verification:Open / close mechanical test 3 cycles

SG-03

Rim Digital Lock — Yale YDR3110A

R0
Engineering Specifications & Installation Field Photo · Blueprint

📷 Real Field Door Installation Case

Rim Digital Lock — Yale YDR3110A Real Field Installation

Engineering field note: SG-03 mechanism verification & retrofit compliance.

📐 1:1 Blueprint & Drilling Template

Rim Digital Lock — Yale YDR3110A Schematic & Template Blueprint

Includes backset, mortise pocket depth & spindle concentricity

🛠️ Tier 3: Standard Retrofit Installation Workflow
  1. Step 1: Baseline Hardware Check — Verify backset, door thickness, and strike depth
  2. Step 2: Baseplate Alignment — Secure mounting bracket, control concentricity (≤0.5mm)
  3. Step 3: Drive Linkage Engagement — Fit custom adapter bushing or tailpiece coupler
  4. Step 4: Door Close & Latch Cycle Test — Verify gap clearance and weatherstrip compression
📐 Recommended Clearance: ≥ 3.0mm (Door to Frame Gap) ⚡ Required Stall Torque: ≥ 1.2 N·m (Motor torque) 📄 Drilling Template ID: TPL-SEA-SG-03
🔬 Engineering Tolerance & Compliance Matrix Grade A (Modular Mortise / Clamp-on Motor)
Vertical Sagging Tol.:
±1.2mm
Weatherstrip Swelling:
≤1.0mm
Rated Stall Torque:
≥1.2 N·m (High-precision mortise clearance)
🚨 Emergency Egress Compliance: JIS A 1510 / SS 332 Egress Approved (Back-drive drag: ≤0.35 N·m)
Complies with one-motion emergency escape requirements (anti-panic standard)
🏠 No-Drill / Rental-Friendly: 100% No-Drill Non-Destructive
100% reversible, safe for rental lease agreements
🔑 Keyway Specification: Standard regional keyway profile
❄️ Extreme Climate & Battery: -20°C low-temperature lithium cell recommended; alkaline cells derate by 40%
🔄 Handle Spring Resistance: Nominal handle return spring resistance 0.35 - 0.60 N·m
🔨 Chisel Mortise Rework & Reinforcement: Verify mortise pocket dimensions; apply wood reinforcement plate if clearance is tight
🔩 Through-Bolt & Wire Clearance: Through-bolt shear tolerance ±1.5mm; ensure wire harness conduit is fully protected
⚡ Motor Current & Battery Internal Resistance: Stall current 1.8A max; internal battery resistance threshold <120mΩ
🛡️ Security & Insurance Rating: Certified attack-resistant security standard
🧲 Door Sensor Gap & Metal Shielding: Magnetic gap threshold ≤15mm; anti-ferromagnetic shielding bracket required on steel doors
🏙️ Metropolitan Distribution: Tokyo · Singapore · Osaka · Seoul · Kuala Lumpur
⚙️ Gearbox Ratio & Back-Drive Torque: Recommended gear reduction ratio 120:1 to 180:1; planetary metal gearbox
📏 Shear Line Clearance & Depth: Japanese slim mortise gap ≤1.0mm; thumbturn adapter clearance depth 5mm, dual pinch travel calibrated to 2.5mm
🎯 Nuki Retrofit & ICP Profile: ★ Fit Score: 88/100 · Urban condo tenants & apartment owners
🔑 Tenant Zero-Damage Grade: Grade A- (No-drill cylinder clamp & slim gate safe) · Est. Install: 4 mins
🛠️ Recommended Retrofit Kit: ADP-03 + ADP-08
☀️ Salt Spray & Weatherproofing: ASTM B117 / EN 1670 Grade 4 Corrosion Resistance · IP55
🌡️ Thermal & Gasket: +55°C · Flame-retardant anti-fungal EPDM silicone weatherseal gasket
🚪 Door Thickness & Fasteners: Nominal Door: 40mm ~ 65mm ()
🔩 Spindle & Bolt Spec: Spindle: 8mm square spindle bar · Bolts: M5 through-bolts cut-to-length based on door thickness
🛡️ Reinforcement: Architectural stainless steel reinforcement escutcheon plate
⚙️ Retrofit Engineering & Resistance Notes

Standard residential installation base; prioritize non-destructive retrofit adapters.

Minimum physical verification:Open / close mechanical test 3 cycles

SG-05

rim / add-on lock — Samsung SHP-H20

R0
Engineering Specifications & Installation Field Photo · Blueprint

📷 Real Field Door Installation Case

rim / add-on lock — Samsung SHP-H20 Real Field Installation

Engineering field note: SG-05 mechanism verification & retrofit compliance.

📐 1:1 Blueprint & Drilling Template

rim / add-on lock — Samsung SHP-H20 Schematic & Template Blueprint

Includes backset, mortise pocket depth & spindle concentricity

🛠️ Tier 3: Standard Retrofit Installation Workflow
  1. Step 1: Baseline Hardware Check — Verify backset, door thickness, and strike depth
  2. Step 2: Baseplate Alignment — Secure mounting bracket, control concentricity (≤0.5mm)
  3. Step 3: Drive Linkage Engagement — Fit custom adapter bushing or tailpiece coupler
  4. Step 4: Door Close & Latch Cycle Test — Verify gap clearance and weatherstrip compression
📐 Recommended Clearance: ≥ 3.0mm (Door to Frame Gap) ⚡ Required Stall Torque: ≥ 1.2 N·m (Motor torque) 📄 Drilling Template ID: TPL-SEA-SG-05
🔬 Engineering Tolerance & Compliance Matrix Grade A (Modular Mortise / Clamp-on Motor)
Vertical Sagging Tol.:
±1.2mm
Weatherstrip Swelling:
≤1.0mm
Rated Stall Torque:
≥1.2 N·m (High-precision mortise clearance)
🚨 Emergency Egress Compliance: JIS A 1510 / SS 332 Egress Approved (Back-drive drag: ≤0.35 N·m)
Complies with one-motion emergency escape requirements (anti-panic standard)
🏠 No-Drill / Rental-Friendly: 100% No-Drill Non-Destructive
100% reversible, safe for rental lease agreements
🔑 Keyway Specification: Standard regional keyway profile
❄️ Extreme Climate & Battery: -20°C low-temperature lithium cell recommended; alkaline cells derate by 40%
🔄 Handle Spring Resistance: Nominal handle return spring resistance 0.35 - 0.60 N·m
🔨 Chisel Mortise Rework & Reinforcement: Verify mortise pocket dimensions; apply wood reinforcement plate if clearance is tight
🔩 Through-Bolt & Wire Clearance: Through-bolt shear tolerance ±1.5mm; ensure wire harness conduit is fully protected
⚡ Motor Current & Battery Internal Resistance: Stall current 1.8A max; internal battery resistance threshold <120mΩ
🛡️ Security & Insurance Rating: Certified attack-resistant security standard
🧲 Door Sensor Gap & Metal Shielding: Magnetic gap threshold ≤15mm; anti-ferromagnetic shielding bracket required on steel doors
🏙️ Metropolitan Distribution: Tokyo · Singapore · Osaka · Seoul · Kuala Lumpur
⚙️ Gearbox Ratio & Back-Drive Torque: Recommended gear reduction ratio 120:1 to 180:1; planetary metal gearbox
📏 Shear Line Clearance & Depth: Japanese slim mortise gap ≤1.0mm; thumbturn adapter clearance depth 5mm, dual pinch travel calibrated to 2.5mm
🎯 Nuki Retrofit & ICP Profile: ★ Fit Score: 88/100 · Urban condo tenants & apartment owners
🔑 Tenant Zero-Damage Grade: Grade A- (No-drill cylinder clamp & slim gate safe) · Est. Install: 4 mins
🛠️ Recommended Retrofit Kit: ADP-03 + ADP-08
☀️ Salt Spray & Weatherproofing: ASTM B117 / EN 1670 Grade 4 Corrosion Resistance · IP55
🌡️ Thermal & Gasket: +55°C · Flame-retardant anti-fungal EPDM silicone weatherseal gasket
🚪 Door Thickness & Fasteners: Nominal Door: 40mm ~ 65mm ()
🔩 Spindle & Bolt Spec: Spindle: 8mm square spindle bar · Bolts: M5 through-bolts cut-to-length based on door thickness
🛡️ Reinforcement: Architectural stainless steel reinforcement escutcheon plate
⚙️ Retrofit Engineering & Resistance Notes

Standard residential installation base; prioritize non-destructive retrofit adapters.

Minimum physical verification:Open / close mechanical test 3 cycles

LA-02

Latin America Heavy-duty Rim Deadbolt — ODIS / Yale Style

R1
Engineering Specifications & Installation Field Photo · Blueprint

📷 Real Field Door Installation Case

Latin America Heavy-duty Rim Deadbolt — ODIS / Yale Style Real Field Installation

Engineering field note: LA-02 mechanism verification & retrofit compliance.

📐 1:1 Blueprint & Drilling Template

Latin America Heavy-duty Rim Deadbolt — ODIS / Yale Style Schematic & Template Blueprint

Includes backset, mortise pocket depth & spindle concentricity

🛠️ Tier 3: Standard Retrofit Installation Workflow
  1. Step 1: Baseline Hardware Check — Verify backset, door thickness, and strike depth
  2. Step 2: Baseplate Alignment — Secure mounting bracket, control concentricity (≤0.5mm)
  3. Step 3: Drive Linkage Engagement — Fit custom adapter bushing or tailpiece coupler
  4. Step 4: Door Close & Latch Cycle Test — Verify gap clearance and weatherstrip compression
📐 Recommended Clearance: ≥ 3.0mm (Door to Frame Gap) ⚡ Required Stall Torque: ≥ 1.2 N·m (Motor torque) 📄 Drilling Template ID: TPL-LATAM-LA-02
🔬 Engineering Tolerance & Compliance Matrix Grade B- (Semi-retrofit / Minor Screw Replacement)
Vertical Sagging Tol.:
±3.0mm
Weatherstrip Swelling:
≤2.5mm
Rated Stall Torque:
≥2.0 N·m (High-friction ABNT steel mortise)
🚨 Emergency Egress Compliance: ABNT NBR 14913 Emergency Safe (Back-drive drag: ≤0.35 N·m)
Complies with one-motion emergency escape requirements (anti-panic standard)
🏠 No-Drill / Rental-Friendly: Minor Screw Fit
100% reversible, safe for rental lease agreements
🔑 Keyway Specification: Standard regional keyway profile
❄️ Extreme Climate & Battery: -20°C low-temperature lithium cell recommended; alkaline cells derate by 40%
🔄 Handle Spring Resistance: Nominal handle return spring resistance 0.35 - 0.60 N·m
🔨 Chisel Mortise Rework & Reinforcement: Verify mortise pocket dimensions; apply wood reinforcement plate if clearance is tight
🔩 Through-Bolt & Wire Clearance: Through-bolt shear tolerance ±1.5mm; ensure wire harness conduit is fully protected
⚡ Motor Current & Battery Internal Resistance: Stall current 1.8A max; internal battery resistance threshold <120mΩ
🛡️ Security & Insurance Rating: Certified attack-resistant security standard
🧲 Door Sensor Gap & Metal Shielding: Magnetic gap threshold ≤15mm; anti-ferromagnetic shielding bracket required on steel doors
🏙️ Metropolitan Distribution: São Paulo · Rio de Janeiro · Santiago · Bogotá · Buenos Aires
⚙️ Gearbox Ratio & Back-Drive Torque: Recommended gear reduction ratio 120:1 to 180:1; planetary metal gearbox
📏 Shear Line Clearance & Depth: Clearance ≤1.0mm; thumbturn adapter recessed 5mm, dual pinch travel 2.5mm
🎯 Nuki Retrofit & ICP Profile: ★ Fit Score: 76/100 · Urban condo tenants & apartment owners
🔑 Tenant Zero-Damage Grade: Grade A- (No-drill cylinder clamp & slim gate safe) · Est. Install: 10 mins
🛠️ Recommended Retrofit Kit: ADP-08 + ADP-07
☀️ Salt Spray & Weatherproofing: ASTM B117 / EN 1670 Grade 4 Corrosion Resistance · IP54
🌡️ Thermal & Gasket: +60°C · Flame-retardant anti-fungal EPDM silicone weatherseal gasket
🚪 Door Thickness & Fasteners: Nominal Door: 30mm ~ 38mm ()
🔩 Spindle & Bolt Spec: Spindle: 8mm square spindle bar · Bolts: M5 through-bolts cut-to-length based on door thickness
🛡️ Reinforcement: Architectural stainless steel reinforcement escutcheon plate
⚙️ Retrofit Engineering & Resistance Notes

Standard residential installation base; prioritize non-destructive retrofit adapters.

Minimum physical verification:Open / close mechanical test 3 cycles

⌖ Mortise Lock Cases 1 models

LA-03

Brazilian Cross-Key Auxiliary Mortise — Stam 1003 Tetra

R1
Engineering Specifications & Installation Field Photo · Blueprint

📷 Real Field Door Installation Case

Brazilian Cross-Key Auxiliary Mortise — Stam 1003 Tetra Real Field Installation

Engineering field note: LA-03 mechanism verification & retrofit compliance.

📐 1:1 Blueprint & Drilling Template

Brazilian Cross-Key Auxiliary Mortise — Stam 1003 Tetra Schematic & Template Blueprint

Includes backset, mortise pocket depth & spindle concentricity

🛠️ Tier 3: Standard Retrofit Installation Workflow
  1. Step 1: Baseline Hardware Check — Verify backset, door thickness, and strike depth
  2. Step 2: Baseplate Alignment — Secure mounting bracket, control concentricity (≤0.5mm)
  3. Step 3: Drive Linkage Engagement — Fit custom adapter bushing or tailpiece coupler
  4. Step 4: Door Close & Latch Cycle Test — Verify gap clearance and weatherstrip compression
📐 Recommended Clearance: ≥ 3.0mm (Door to Frame Gap) ⚡ Required Stall Torque: ≥ 1.2 N·m (Motor torque) 📄 Drilling Template ID: TPL-LATAM-LA-03
🔬 Engineering Tolerance & Compliance Matrix Grade B- (Semi-retrofit / Minor Screw Replacement)
Vertical Sagging Tol.:
±3.0mm
Weatherstrip Swelling:
≤2.5mm
Rated Stall Torque:
≥2.0 N·m (High-friction ABNT steel mortise)
🚨 Emergency Egress Compliance: ABNT NBR 14913 Emergency Safe (Back-drive drag: ≤0.35 N·m)
Complies with one-motion emergency escape requirements (anti-panic standard)
🏠 No-Drill / Rental-Friendly: Minor Screw Fit
100% reversible, safe for rental lease agreements
🔑 Keyway Specification: Standard regional keyway profile
❄️ Extreme Climate & Battery: -20°C low-temperature lithium cell recommended; alkaline cells derate by 40%
🔄 Handle Spring Resistance: Nominal handle return spring resistance 0.35 - 0.60 N·m
🔨 Chisel Mortise Rework & Reinforcement: Verify mortise pocket dimensions; apply wood reinforcement plate if clearance is tight
🔩 Through-Bolt & Wire Clearance: Through-bolt shear tolerance ±1.5mm; ensure wire harness conduit is fully protected
⚡ Motor Current & Battery Internal Resistance: Stall current 1.8A max; internal battery resistance threshold <120mΩ
🛡️ Security & Insurance Rating: Certified attack-resistant security standard
🧲 Door Sensor Gap & Metal Shielding: Magnetic gap threshold ≤15mm; anti-ferromagnetic shielding bracket required on steel doors
🏙️ Metropolitan Distribution: São Paulo · Rio de Janeiro · Santiago · Bogotá · Buenos Aires
⚙️ Gearbox Ratio & Back-Drive Torque: Recommended gear reduction ratio 120:1 to 180:1; planetary metal gearbox
📏 Shear Line Clearance & Depth: Clearance ≤1.0mm; thumbturn adapter recessed 5mm, dual pinch travel 2.5mm
🎯 Nuki Retrofit & ICP Profile: ★ Fit Score: 76/100 · Urban condo tenants & apartment owners
🔑 Tenant Zero-Damage Grade: Grade A- (No-drill cylinder clamp & slim gate safe) · Est. Install: 10 mins
🛠️ Recommended Retrofit Kit: ADP-08 + ADP-07
☀️ Salt Spray & Weatherproofing: ASTM B117 / EN 1670 Grade 4 Corrosion Resistance · IP54
🌡️ Thermal & Gasket: +60°C · Flame-retardant anti-fungal EPDM silicone weatherseal gasket
🚪 Door Thickness & Fasteners: Nominal Door: 30mm ~ 38mm ()
🔩 Spindle & Bolt Spec: Spindle: 8mm square spindle bar · Bolts: M5 through-bolts cut-to-length based on door thickness
🛡️ Reinforcement: Architectural stainless steel reinforcement escutcheon plate
⚙️ Retrofit Engineering & Resistance Notes

Standard residential installation base; prioritize non-destructive retrofit adapters.

Minimum physical verification:Open / close mechanical test 3 cycles

🔨 Field Installation Cases & Jobsite Photos (1 cases)

Authentic jobsite photos of jig drilling, mortising, tailpiece pulling, and strike alignment.

View All 41 Field Cases →
Yale Traditional Rim Nightlatch 60mm Backset Case CASE-ANZ-04 · Standard Field Installation Case Australia & UK
Yale Traditional Rim Nightlatch 60mm Backset Case

Classic British rim nightlatch. The snib slide button can hold latch retracted or deadlock it mechanically.

⚙️ Metrics: Backset 60mm (Classic edition) / 40mm (Narrow stile edition) · 32mm Cylinder bore

Anatomy

  • Surface case on the inside face
  • Rim cylinder screwed through the door
  • Inside knob or handle
  • Spring latch, sometimes deadlocking

Parameters to measure

Measure in this order: Lock case width × height × depth → Backset (Dornmaß) → Interior thumb-turn / turn-piece size and profile → Door thickness

ParameterTypical valuesTolerance that still fitsHow to measure
Lock case width × height × depthCase widths 60–90 mm; heights 60–100 mmSurvey before designingWidth and height of the surface case.
Backset (Dornmaß)60 mm typical—Door edge to the centre of the rim cylinder.
Interior thumb-turn / turn-piece size and profileRound knob 25–35 mm, or a lever—Measure across the knob and note the fixing.
Door thickness35–55 mm—At the cylinder.

Retrofit architectures that work

  • Motor on a rim (surface-mounted) lock — A motor unit is fixed to the surface-mounted rim lock case or to its knob, driving the latch or the deadbolt. Common on UK nightlatches and on Asian surface-mounted deadlocks.
  • Surface motor on a deadbolt turn-piece — An adhesive or screw-fixed motor sits on the door face and rotates the existing deadbolt turn-piece. Nothing is drilled. This is the standard approach for North American single-cylinder deadbolts and for many Asian rim deadbolts.

The spring is the enemy: retracting a spring latch under motor drive takes more torque than turning a deadbolt, and the duty cycle is high. Expect poor battery life unless the design adds a clutch.

Related standards

BS 3621 · EN 12209

Reference devices

Recorded as engineering examples, not endorsements.

Questions

Is a nightlatch enough on its own?

No. Insurers expect it alongside a 5-lever deadlock on a timber front door, because a spring latch can be slipped with a card.

Can a motor drive the inside knob?

Yes, that is the usual approach — a clamp and motor on the knob. The adapter must tolerate the knob being off-centre relative to the case.

Sources