Norsound NOR810S+ Automatic Drop Seal – 12 × 30mm is a rebated door-bottom seal designed to reduce sound, cold smoke, draughts, light and uncontrolled airflow through the gap beneath a timber doorset.
The compact aluminium profile is mortised into the bottom edge of the door leaf and secured using two fixing screws.
When the door closes, a single mechanical actuator activates the internal mechanism and lowers the grey TPE gasket onto the finished floor, sill or threshold plate.
As the door opens, the gasket retracts into the aluminium housing, maintaining floor clearance and helping prevent unnecessary wear caused by continuous contact with the floor.
The NOR810S+ is designed for installation at the bottom edge of acoustic timber doorsets.
It can help:
The NOR810S+ treats only the bottom edge of the door. Suitable perimeter seals are normally required around the head and jambs to complete the sealing system.
The seal contains a mechanically operated internal drop mechanism.
An adjustable actuator is located at the hinge side of the door. As the door reaches its closed position, the actuator contacts the frame and activates the mechanism.
The flexible TPE gasket then lowers towards the floor or threshold.
When the door opens, pressure is released from the actuator and the gasket retracts into the aluminium housing.
The NOR810S+ requires:
The aluminium housing has a nominal profile size of:
It is concealed within a routed groove along the bottom of the door.
The 30mm-deep profile provides greater gasket travel than the standard NOR810S while remaining narrower and shallower than the 14 × 35mm NOR810.
The door must contain sufficient solid material to receive the 12mm-wide × 30mm-deep mortise without damaging its structural core, lippings, glazing system or other components.
The NOR810S+ can cover a threshold gap of up to 15mm.
The actual permitted gap may also be limited by:
The gasket should make light and continuous contact with the finished threshold when the door is closed.
Excessive actuator travel can:
Norseal specifies the NOR810S+ for the bottom edge of acoustic timber doorsets.
The gasket helps reduce sound transmission by closing the open air path beneath the door when it is shut.
The individual drop seal does not have a universal standalone decibel rating.
Final acoustic performance depends on the complete doorset, including:
For effective sound control, the entire door perimeter should be treated rather than sealing only the bottom edge.
Norseal states that the NOR810S+ meets the smoke requirements of BS 8214 within appropriate doorset arrangements.
When correctly installed and adjusted, the TPE gasket helps restrict smoke passing through the threshold gap.
The complete smoke-sealing arrangement may also require:
The NOR810S+ does not independently establish the smoke classification of a complete door assembly.
Norseal states that the NOR810S+ is suitable for use on most fire doors.
This does not provide a standalone fire-resistance rating for the individual drop seal.
Before routing a fire-resisting door, confirm:
Unauthorised machining may invalidate the certification, assessment or warranty applying to a fire door.
The NOR810S+ is installed into a routed groove along the full width of the door bottom.
The manufacturer’s fitting arrangement includes:
The aluminium housing is inserted into the mortise and secured using the two supplied screws.
The push-fit end cap is installed at the non-hinge side of the door.
The NOR810S+ uses one adjustable actuator positioned at the hinge side.
The actuator can be adjusted using a screwdriver:
The seal can also be deactivated by removing the actuator.
Removing the actuator prevents the gasket from lowering and therefore removes the intended acoustic and smoke-sealing function at the threshold.
The flexible sealing element is manufactured from grey TPE.
The gasket provides:
Keep the gasket free from:
The mechanism is enclosed within a mill-finish aluminium profile.
The aluminium housing provides:
Most of the housing is concealed once the seal has been mortised into the door.
The NOR810S+ can close against a suitable:
A threshold plate may improve performance where the existing floor is:
The actuator should be adjusted after the final floor and threshold finishes have been completed.
The NOR810S+ is available in the following standard lengths:
Select the nearest suitable supplied length that can be shortened to the required door width without exceeding its cut-back allowance.
The NOR810S+ can be shortened at the non-actuator end.
The manufacturer states:
Always check the maximum cut-back stated on the individual product label before cutting.
Cutting beyond the permitted limit can damage the internal mechanism and prevent the seal from operating.
The NOR810S+ and NOR810S share the same nominal 12mm profile width but have different depths and maximum drops.
| Product | Profile | Maximum Gap Coverage | Maximum Standard Length |
|---|---|---|---|
| NOR810S | 12 × 20mm | 12mm | 1225mm |
| NOR810S+ | 12 × 30mm | 15mm | 1325mm |
The NOR810S+ may be appropriate where greater gasket travel or a longer supplied seal is required, provided the door can accommodate the deeper 30mm mortise.
The NOR810 measures 14 × 35mm and covers gaps of up to 20mm.
The NOR810S+ measures 12 × 30mm and covers gaps of up to 15mm.
The correct product must be selected according to:
The NOR810S+ can be used within appropriate doorsets in:
Before ordering, confirm:
Do not machine a fire-rated, hollow-core, glazed or specialist door until the proposed installation has been checked against the applicable doorset documentation.
Norsound NOR810S+ Automatic Drop Seal is a rebated and screw-fixed automatic door-bottom seal with a mill-finish aluminium housing, grey TPE gasket and single mechanical actuator.
| Product Name | Norsound NOR810S+ Automatic Drop Seal – 12 × 30mm |
| Brand | Norsound by Norseal |
| Product Reference | NOR810S+ |
| Product Type | Rebated automatic acoustic and smoke door-bottom seal |
| Application | Bottom edge of acoustic timber doorsets |
| Installation Method | Mortised into the bottom edge of the door and screw-fixed |
| Profile Width | 12mm |
| Profile Depth | 30mm |
| Maximum Gap Coverage | 15mm |
| Actuation | Single mechanical actuator |
| Actuator Position | Hinge side of the door |
| Actuator Adjustment | Adjustable using a screwdriver |
| Adjustment Direction | Clockwise reduces the drop distance; anti-clockwise increases the drop distance |
| Deactivation | The mechanism can be deactivated by removing the actuator |
| Power Requirement | None — mechanically operated |
| Housing Material | Aluminium |
| Housing Finish | Mill finish |
| Gasket Material | TPE |
| Gasket Colour | Grey |
| End-Cap Colour | Black |
| Smoke Performance | Meets the smoke requirements of BS 8214 within appropriate doorset arrangements |
| Fire-Door Application | Suitable for use on most fire doors, subject to the complete doorset evidence |
| Standard Lengths | 325, 425, 525, 625, 725, 825, 925, 1025, 1125, 1225 and 1325mm |
| Maximum Standard Length | 1325mm |
| General Cut-Back | 125mm |
| 425mm Cut-Back | Maximum 105mm |
| 325mm Cut-Back | Can be shortened only to approximately 320mm |
| Fixings Supplied | Two fixing screws |
| End Component | One push-fit end cap for the non-hinge side |
| Standalone Acoustic Rating? | No universal standalone rating is stated; performance depends on the complete doorset |
| Standalone Fire Rating? | No — fire performance depends on the complete tested or assessed doorset |
| Length | Profile Size | Finish | Maximum Cut-Back | Product Code |
|---|---|---|---|---|
| 325mm | 12 × 30mm | Mill finish / Grey gasket | 5mm — minimum finished length approximately 320mm | NOR810S+/0325 |
| 425mm | 12 × 30mm | Mill finish / Grey gasket | 105mm | NOR810S+/0425 |
| 525mm | 12 × 30mm | Mill finish / Grey gasket | 125mm | NOR810S+/0525 |
| 625mm | 12 × 30mm | Mill finish / Grey gasket | 125mm | NOR810S+/0625 |
| 725mm | 12 × 30mm | Mill finish / Grey gasket | 125mm | NOR810S+/0725 |
| 825mm | 12 × 30mm | Mill finish / Grey gasket | 125mm | NOR810S+/0825 |
| 925mm | 12 × 30mm | Mill finish / Grey gasket | 125mm | NOR810S+/0925 |
| 1025mm | 12 × 30mm | Mill finish / Grey gasket | 125mm | NOR810S+/1025 |
| 1125mm | 12 × 30mm | Mill finish / Grey gasket | 125mm | NOR810S+/1125 |
| 1225mm | 12 × 30mm | Mill finish / Grey gasket | 125mm | NOR810S+/1225 |
| 1325mm | 12 × 30mm | Mill finish / Grey gasket | 125mm | NOR810S+/1325 |
Norseal’s general manufacturer order-code format is:
NOR810S+ + supplied length
For example:
The slash-separated product codes in the table above are those used within the current supplied product range.
Choose a supplied seal that is longer than the required finished length but remains within its stated cut-back limit.
| Supplied Length | Maximum Cut-Back | Approximate Minimum Finished Length |
|---|---|---|
| 325mm | 5mm | 320mm |
| 425mm | 105mm | 320mm |
| 525mm | 125mm | 400mm |
| 625mm | 125mm | 500mm |
| 725mm | 125mm | 600mm |
| 825mm | 125mm | 700mm |
| 925mm | 125mm | 800mm |
| 1025mm | 125mm | 900mm |
| 1125mm | 125mm | 1000mm |
| 1225mm | 125mm | 1100mm |
| 1325mm | 125mm | 1200mm |
The approximate minimum finished lengths are calculated from the manufacturer’s stated maximum cut-back figures. Always check the limit printed on the individual product label before cutting.
The NOR810S+ is designed for the bottom edge of acoustic timber doorsets.
No universal standalone decibel rating should be assigned to the individual product.
Final sound reduction depends on:
The NOR810S+ meets the smoke requirements of BS 8214 within appropriate complete doorset arrangements.
The TPE gasket must make continuous contact with the finished floor, sill or threshold when the door is closed.
A compatible smoke-sealing system will normally also be required around the door head and jambs.
Norseal states that the NOR810S+ is suitable for use on most fire doors.
This does not provide a standalone fire rating.
Before installation:
The NOR810S+ can close against a suitable floor, sill or threshold plate.
A threshold plate may improve gasket contact where the floor is:
Complete the final actuator adjustment only after the threshold and floor finishes have been installed.
Store the NOR810S+:
Do not allow debris to enter the internal mechanism.
Norsound NOR810S+ Automatic Drop Seal is installed into a 12mm-wide × 30mm-deep routed groove along the full width of the bottom edge of a suitable timber door leaf.
The seal is cut to approximately 5mm less than the measured door width, inserted into the groove and secured using the two supplied fixing screws.
The actuator must be positioned at the hinge side, with the push-fit end cap installed at the non-hinge side.
Inspect the door, frame and threshold.
Confirm that:
Do not machine a fire-rated, hollow-core, glazed or specialist door without confirming that the installation is permitted.
Confirm that the package contains:
Identify:
Do not begin cutting until the permitted cut-back has been confirmed.
The maximum cut-back depends on the supplied length:
The product label takes priority where it states a different or more restrictive limit.
Cutting beyond the marked point can damage the internal mechanism.
Remove the door from its hinges where necessary.
Lay it securely on its side and restrain it firmly.
Support the complete door to prevent movement or twisting while routing.
Protect:
Measure the width of the door along its bottom edge.
Record the measurement as L.
Measure at the exact installation position rather than assuming the door is perfectly square.
Mark a straight mortise across the complete width of the door bottom.
The required groove is:
Check that sufficient door material will remain on both faces after routing.
Use a router, 12mm cutter and suitable guide to machine the groove.
Remove the timber in controlled passes rather than attempting the complete 30mm depth in one operation.
Maintain:
Avoid cutting into structural rails, glazing systems, fixings or other internal door components.
Remove all timber dust, chips and loose fibres.
Use a brush or vacuum to clear the mortise.
Check that:
The manufacturer’s fitting instructions require the seal to be cut to:
L − 5mm
Measure from the actuator end and mark the aluminium housing at the calculated length.
For example:
Confirm that the required shortening remains within the cut-back limit for the selected seal.
Measure the finished length from the actuator end.
Remove the excess material from the opposite, non-actuator end.
Before cutting, reconfirm:
Do not shorten the actuator end.
Partially withdraw or slide the flexible gasket away from the cutting line.
Move enough gasket clear of the saw to prevent accidental damage.
Do not:
Support the seal securely and cut the aluminium housing squarely at the marked position.
Use a suitable fine-tooth saw.
After cutting:
Return the TPE gasket to its natural position within the aluminium housing.
Trim it cleanly to the finished length.
Do not stretch the gasket while cutting, as it may retract and finish too short.
Confirm that the gasket remains:
Place the prepared seal into the routed groove.
Position the actuator at the hinge side of the door.
Check that:
Mark and drill suitable pilot holes where required.
Secure the drop seal using the two supplied fixing screws.
Tighten the screws evenly.
Do not overtighten them, as this can:
Push the supplied end cap into place at the non-hinge side of the seal.
Check that it is fully seated and does not interfere with the gasket or drop mechanism.
Return the door to its frame and secure it correctly to the hinges.
Check that:
Close the door slowly while observing the gasket.
The seal should:
Use a screwdriver to adjust the actuator.
Make small adjustments:
Open and close the door after each adjustment.
Continue until the gasket touches the floor or threshold without excessive compression.
Close the door and inspect the complete gasket.
Confirm that:
Where the floor is uneven or compressible, install a suitable threshold plate rather than over-adjusting the drop seal.
Operate the door several times.
Confirm that:
The NOR810S+ can be deactivated by removing the actuator.
When the actuator is removed, the gasket will not lower as the door closes.
Deactivation therefore removes the intended acoustic and smoke-sealing function at the threshold and should not be used where an operational drop seal is required by the doorset specification.
Where a threshold plate is required, install it before completing the final actuator adjustment.
The threshold plate should:
Readjust the NOR810S+ after the final threshold surface has been installed.
The NOR810S+ treats only the gap beneath the door.
Suitable perimeter seals will normally also be required around the:
Use the complete sealing arrangement specified by the applicable acoustic, smoke or fire doorset evidence.
Inspect and operate the NOR810S+ regularly as part of the door-maintenance programme.
Check for:
Clean the gasket and threshold using a soft cloth and a suitable mild cleaning product.
Do not apply unapproved oil, grease or lubricant to the internal mechanism.
Correct machining, cutting, fixing and actuator adjustment are essential to the operation of the NOR810S+.
The product does not independently create an acoustically rated, smoke-control or fire-resisting door.
Final performance depends on:
For certified doorsets, install the NOR810S+ only in accordance with the applicable test evidence, assessment, certification and door-manufacturer instructions.
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