Norseal NOR810 Acoustic Door Seal is a high-performance automatic drop seal designed to reduce sound, smoke, draught and light transfer through the gap beneath a door.
The NOR810 is rebated into a machined groove along the bottom edge of the door, creating a discreet installation with the main aluminium mechanism concealed inside the door leaf.
As the door closes, a single actuator at the hinge side activates the internal mechanism and lowers the flexible silicone gasket onto the floor or threshold. When the door opens, the gasket automatically retracts to reduce friction, floor contact and seal wear.
The NOR810 is installed along the bottom edge of acoustic timber doorsets.
An untreated gap beneath a door can allow a significant amount of airborne sound, smoke, draughts and visible light to pass between adjoining spaces.
The NOR810 automatically closes this gap when the door shuts, making it suitable for:
The NOR810 uses a mechanically operated actuator positioned at the hinge side of the door.
As the door closes, the actuator contacts the frame and activates the internal drop mechanism. The silicone gasket lowers towards the floor and forms a seal across the bottom of the doorway.
When the door begins to open, pressure is released from the actuator and the gasket retracts into the aluminium housing.
This automatic operation helps prevent the gasket from dragging continuously across the floor.
The current NOR810 uses a robust internal mechanism designed to lower the gasket evenly across the width of the door.
Its self-levelling action helps the seal maintain contact where the floor or threshold is not completely level.
The mechanism should be adjusted so the gasket makes light and continuous contact when the door closes without excessive compression or over-travel.
The NOR810 has been acoustically tested in accordance with BS EN ISO 10140-2:2010.
Norseal states acoustic performance values of up to 51dB within the relevant tested door and sealing arrangements.
This figure applies to a complete tested doorset configuration. It should not be treated as an independent 51dB rating for the NOR810 alone.
Final acoustic performance will depend on:
For effective sound reduction, the gaps around the entire door must be treated rather than sealing only the bottom edge.
The NOR810 has been smoke tested in accordance with BS 476-31.1.
It can contribute towards smoke containment by closing the otherwise open gap beneath the door.
The NOR810 should be combined with suitable smoke and acoustic perimeter seals around the door head and jambs.
Final smoke performance depends on the complete tested door assembly, including:
The current NOR810 literature states that the seal is compliant with BS 476 Part 20/22 and has been fire tested for use in suitable doorsets for up to 60 minutes.
The product is also associated with Certifire reference CF629 and UL approval within relevant tested systems.
This does not mean that the NOR810 independently gives a door 30 or 60 minutes of fire resistance.
Before installing the seal into a fire-resisting door, confirm:
The NOR810 is installed into a groove machined along the bottom edge of the door.
The required main mortise measures:
The end of the door is also recessed to accommodate the end plates.
Once installed, the seal is held in position using traditional end plates. Optional hanging brackets may also be available for faster installation where appropriate.
The NOR810 can cover gaps of up to 20mm.
The actuator is adjustable so the installer can set the amount of gasket movement required for the actual gap beneath the door.
The gasket should touch the floor or threshold when the door closes, but it should not be adjusted so far that it over-travels, folds excessively or prevents the door from closing correctly.
The NOR810 is designed primarily for:
The door must be thick enough and constructed appropriately to receive the required 14mm-wide × 35mm-deep mortise.
Suitable applications can include:
Yes. The NOR810 can close directly onto a suitable smooth and level floor, sill or threshold plate.
A threshold plate is particularly useful where the existing surface is:
A firm threshold surface helps the silicone gasket maintain more consistent contact across the doorway.
Yes. A suitable perimeter seal should normally be installed around the:
The NOR810 then treats the remaining gap beneath the door.
Norseal’s NOR710 perimeter seal is one example of a compatible seal used within tested acoustic and smoke-control doorset arrangements.
Measure the door width and check the construction of the door before selecting a NOR810 length.
Standard supplied lengths range from 320mm to 1535mm. Each size has a specified cut-back limit that must be checked on the product label before cutting.
The 320mm version has a restricted cut-back and can be reduced to approximately 235mm. Other standard sizes provide at least 100mm of cut-back, but the exact permitted reduction depends on the selected length.
Also confirm:
Do not machine a fire-rated, hollow, glazed or specialist door until the proposed mortise has been checked against the door manufacturer’s instructions.
Norseal NOR810 is a rebated automatic door-bottom seal with an aluminium housing, self-levelling silicone gasket and single hinge-side actuator.
| Product Name | Norseal NOR810 Acoustic Door Seal |
| Brand | Norsound by Norseal |
| Product Reference | NOR810 |
| Product Type | Automatic rebated acoustic door-bottom seal |
| Application | Bottom edge of acoustic timber doorsets |
| Door Configurations | Single-leaf and double-leaf swing doors |
| Installation Type | Rebated or mortised into the bottom edge of the door |
| Fixing | Held in place with traditional end plates or optional hanging brackets |
| Body Size | 14mm wide × 35mm deep |
| End-Plate Recess | Approximately 22mm × 60mm × 1mm deep at each end, according to the current fitting drawing |
| Maximum Gap Coverage | 20mm |
| Actuation | Single actuator with parallel, self-levelling drop operation |
| Actuator Position | Hinge side of the door |
| Actuator Type | Removable clip-in actuator, adjustable by hand |
| Adjustment Direction | Clockwise reduces gasket movement; anti-clockwise increases gasket movement |
| Self-Levelling | Yes |
| Power Requirement | None — mechanically operated |
| Housing Material | Aluminium |
| Gasket Material | Silicone |
| Housing Finish | Mill-finish aluminium |
| Standard Gasket Colour | Light grey |
| Standard Actuator Colour | Light grey |
| Acoustic Test Standard | BS EN ISO 10140-2:2010 |
| Maximum Published Acoustic Performance | Up to 51dB within relevant tested complete doorset arrangements |
| Smoke Test Standard | BS 476-31.1 |
| Fire Test Standard | BS 476 Part 20/22 |
| Maximum Published Fire Performance | Suitable for relevant tested doorsets up to 60 minutes |
| Certifire Reference | CF629 within the relevant approved smoke-sealing systems |
| UL Approval | Manufacturer literature lists UL approval |
| Durability | Tested to 1,000,000 operating cycles by an external test house |
| Containment Functions | Contributes towards acoustic, smoke, draught, light and energy-loss control |
| Suitable for Wheeled Traffic | Yes — the gasket retracts when the door opens |
| Standalone Acoustic Rating? | No — the published acoustic performance applies to complete tested doorset arrangements |
| Standalone Fire Rating? | No — fire performance depends on the complete tested or assessed doorset |
| Product | Supplied Length | Order Code Format |
|---|---|---|
| NOR810 320 | 320mm | NOR810320 |
| NOR810 435 | 435mm | NOR810435 |
| NOR810 535 | 535mm | NOR810535 |
| NOR810 635 | 635mm | NOR810635 |
| NOR810 735 | 735mm | NOR810735 |
| NOR810 835 | 835mm | NOR810835 |
| NOR810 935 | 935mm | NOR810935 |
| NOR810 1035 | 1035mm | NOR8101035 |
| NOR810 1135 | 1135mm | NOR8101135 |
| NOR810 1235 | 1235mm | NOR8101235 |
| NOR810 1335 | 1335mm | NOR8101335 |
| NOR810 1435 | 1435mm | NOR8101435 |
| NOR810 1535 | 1535mm | NOR8101535 |
Each supplied length has a specific maximum cut-back allowance.
Current Norseal literature states:
Never shorten the product beyond its marked cut-back limit. Excessive cutting can damage or disable the internal drop mechanism.
The standard fitting instructions list:
Optional hanging brackets may be available separately where an alternative fixing arrangement is required.
The NOR810 can be used on:
Norseal publishes acoustic performance values of up to 51dB in accordance with BS EN ISO 10140-2:2010.
This performance applies to the relevant complete doorset and sealing configuration.
The NOR810 does not independently provide a 51dB sound reduction rating.
Final acoustic performance depends on:
The NOR810 has been smoke tested in accordance with BS 476-31.1.
Certifire reference CF629 includes relevant smoke-sealing arrangements involving Norseal perimeter and automatic threshold seals.
The NOR810 must be installed with the correct perimeter seals and within a suitable doorset configuration where certified smoke performance is required.
Current Norseal literature states that the NOR810 is compliant with BS 476 Part 20/22 and has been tested for use in suitable doorsets up to 60 minutes.
This must not be interpreted as an independent 60-minute rating for the seal.
For a fire-resisting door:
The NOR810 can operate against a suitable smooth floor, sill or threshold plate.
A threshold plate may improve gasket contact where the existing surface is:
The selected threshold must leave sufficient clearance for the seal to retract and operate correctly.
Store the NOR810:
Do not allow timber dust, metal swarf or site debris to enter the internal mechanism.
Norseal NOR810 Acoustic Door Seal is rebated into a groove machined along the bottom edge of the door.
The actuator must be positioned at the hinge side, and the end plate containing the black plastic distance piece must be installed at the non-actuator end.
The product must not be shortened beyond the maximum cut-back stated on its label.
Always check the current Norseal fitting instructions and the evidence for the complete doorset before machining or installing the seal.
Inspect the door, frame and threshold before machining or fitting the NOR810.
Check that:
Do not machine a fire-rated, hollow, glazed or specialist door until the proposed mortise has been checked against the door manufacturer’s evidence.
Remove the NOR810 from its packaging and identify:
Do not begin cutting until the permitted cut-back has been confirmed.
The 320mm version has a restricted maximum cut-back of approximately 85mm. Other standard sizes provide at least 100mm of cut-back, but the exact allowance must be taken from the product label.
Where the door is already installed, remove it from its hinges.
Lay the door securely on its side and restrain it so that it cannot move while being measured, routed or cut.
Support the door across its full length to avoid:
Mark the position of the NOR810 along the bottom edge of the door.
The main groove must run continuously across the full width of the door and measure:
Keep the mortise straight and correctly aligned within the door thickness.
Check that enough material will remain on both faces of the door after machining.
The fitting drawing shows an end-plate profile measuring approximately:
Mark a shallow recess at each end of the door to allow the end plates to finish correctly against the door edge.
The end-plate recess must align with the main 14mm × 35mm groove.
Using a router and suitable guide, machine the main mortise along the bottom of the door.
Route the groove in controlled passes rather than attempting to remove the full 35mm depth in one pass.
Machine the shallow end-plate recesses at both sides of the door.
Maintain consistent dimensions throughout the groove.
Use suitable extraction to control timber dust and chips.
Remove all timber dust, chips and debris from the machined areas.
Measure the groove to confirm that it is:
Check that the end-plate recesses are clean and correctly aligned.
Measure the width of the door and record it as measurement W.
The current fitting guide instructs the installer to cut the NOR810 to:
W − 5mm
This provides the necessary clearance for the end plates and finished installation.
Check that the required finished length remains within the permitted cut-back shown on the product label.
Before cutting, push the internal profile towards the closing stile as instructed by Norseal.
Make sure the mechanism is correctly positioned before marking the cut line.
This is important because the outer housing, internal profile and silicone gasket must finish at the correct relative lengths.
Measure from the actuator end of the NOR810.
Mark the required finished length of W − 5mm on the end that is to be shortened.
Check:
Do not cut until all measurements have been confirmed.
Partially remove or pull back the silicone gasket from the area being cut.
Move enough gasket away from the saw line to prevent accidental damage.
Do not:
Cut the aluminium housing and internal profile at the marked position.
Support the seal securely while cutting to prevent vibration or distortion.
After cutting:
Do not leave cutting debris inside the seal.
Return the silicone gasket to its correct position.
Trim the gasket to the same finished length as the internal profile using a sharp knife, scissors or suitable snips.
Allow the gasket to sit naturally without stretching, twisting or bunching.
Make sure the supplied black plastic distance piece is correctly located on the appropriate end plate.
The end plate with the black plastic distance piece must be fitted at the non-actuator end of the NOR810.
Do not omit this component, as it controls the required internal clearance and helps prevent the mechanism from over-travelling.
Place the NOR810 into the machined groove.
Check that:
Fix the NOR810 into position through the supplied end plates using the two supplied screws.
Use a standard PH2 Phillips screwdriver.
The end plate containing the black plastic distance piece must be installed at the non-actuator end.
Tighten the screws sufficiently to hold the product securely, but do not overtighten them.
Excessive tightening may:
Return the door to its frame and refit it securely to the hinges.
Confirm that:
Close the door while observing the silicone gasket.
The gasket should:
Check that the mechanism does not over-travel.
Remove the clip-in actuator from the hinge-side end of the seal.
The current NOR810 actuator can be removed and adjusted by hand without specialist tools.
Keep the actuator clean and avoid damaging its threaded adjustment section.
Turn the actuator to change the gasket movement:
Refit the actuator after making a small adjustment, then close the door and test the seal again.
Repeat the adjustment until the silicone gasket makes light and continuous contact.
The gasket should touch the floor or threshold without being driven down further than necessary.
Excessive over-travel can:
Reduce the actuator movement if the gasket is excessively compressed.
Close the door and inspect the gasket along its full width.
Check that:
Where the floor is too uneven or soft, install a suitable threshold plate to create a firmer sealing surface.
Open and close the door several times.
Confirm that:
The NOR810 should be combined with suitable acoustic and smoke perimeter seals.
Perimeter seals treat the gaps around the:
The NOR810 treats the remaining gap beneath the door.
For tested acoustic, smoke or fire performance, use the complete component arrangement stated in the applicable doorset evidence.
A threshold plate can provide a firm and level contact surface beneath the NOR810.
This is useful where the existing floor is:
The threshold plate must not reduce the available clearance so far that the door or drop seal cannot operate correctly.
After fitting a threshold plate, readjust the NOR810 actuator so the gasket makes light and continuous contact.
Inspect and test the NOR810 periodically as part of the door’s normal maintenance programme.
Check for:
Clean the gasket and threshold using a soft cloth and a suitable mild cleaning product.
Avoid abrasive tools, aggressive chemicals and unapproved lubricants.
Readjust the actuator if the door settles, the hinges move or the threshold height changes.
Correct machining, cutting, positioning and adjustment are essential to the performance of the NOR810.
The silicone gasket should make continuous contact with the floor or threshold when the door closes, but it must not be adjusted so heavily that it prevents the door from operating correctly.
Final acoustic, smoke and fire performance depends on the complete door assembly, including:
For certified acoustic, smoke or fire-resisting doorsets, follow the applicable test evidence, assessment and door manufacturer’s instructions in addition to this general installation guidance.
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