Lorient LAS8007 si Drop Seal is a heavy-duty, fully mortised automatic door-bottom seal designed to reduce sound, smoke, draught and light transfer through the gap beneath a door.
The seal is recessed into a machined groove in the bottom edge of the door, leaving only the silicone sealing gasket and end plates visible once installation is complete.
Its spring-loaded mechanical system automatically lowers the gasket as the door closes and retracts it when the door opens. No electrical connection is required.
The LAS8007 si is the fully mortised version of the Lorient LAS8006 si.
The LAS8007 si is installed within the bottom edge of a door to seal the gap between the door leaf and the floor, sill or threshold plate.
Unsealed gaps beneath doors can allow sound, smoke, draughts and light to pass between adjoining spaces. The LAS8007 si closes this gap automatically when the door shuts and lifts clear when the door opens.
It is commonly used for:
The LAS8007 si contains a mechanical drop-seal system operated by an actuator button at the hinge side of the door.
As the door closes, the actuator button contacts the door stop. This activates the internal mechanism and lowers the flexible silicone gasket onto the floor, sill or threshold plate.
When the door begins to open, pressure is released from the actuator button and the gasket lifts clear of the floor after only a few millimetres of door movement.
This helps reduce:
The LAS8007 si is a fully mortised drop seal.
It is installed inside a groove machined along the bottom edge of the door. Lorient’s current fitting guide specifies a groove measuring:
Once fitted, the aluminium housing is concealed within the door leaf, creating a discreet finish.
Mortised installation is generally better suited to new doors, workshop preparation or doors that can safely accommodate the required groove.
The LAS8007 si has acoustic test evidence of up to Rw 39dB in accordance with BS EN ISO 10140-1:2010+A2:2014, Annex J.
The quoted acoustic performance applies to the relevant tested complete door assembly and sealing arrangement. It is not a standalone 39dB rating for the drop seal itself.
Final acoustic performance will depend on:
For effective acoustic containment, suitable seals should also be installed around the head and jambs of the door.
The LAS8007 si has been tested for smoke containment to BS 476-31.1:1983 at ambient temperature.
It can contribute towards smoke containment by closing the otherwise open gap beneath a door.
The drop seal should be combined with suitable perimeter smoke seals around the head and jambs. Final smoke performance depends on the construction, condition and tested configuration of the complete doorset.
The LAS8007 si carries Certifire reference CF5179 and UL classification reference R27972.
The current fitting guide also shows positive-pressure gasketing classification information for use with specified fire-door constructions.
These references should not be treated as a standalone UK fire-resistance rating for the drop seal.
Before installing the LAS8007 si on a fire-resisting door, confirm:
The LAS8007 si is designed to self-level across slightly uneven floor or threshold surfaces.
The gasket begins to lower from the hinge side and adjusts across the doorway as the door reaches its closed position.
The seal movement can be adjusted independently of the fixing screws by turning the actuator button.
This allows the installer to achieve light and consistent contact without moving the aluminium housing.
Lorient states a published operating range of:
The actuator should be adjusted so the silicone gasket touches the sill or threshold during the final closing movement of the door.
The gasket should make continuous contact without being excessively compressed.
The LAS8007 si is suitable for:
The actuator button must be positioned at the hinge side so that it meets the door stop as the door closes.
Suitable applications can include:
Yes. Lorient states that the LAS8007 si can be used with any suitable threshold plate.
A threshold plate provides a firm, smooth and consistent surface against which the silicone gasket can close.
This can be particularly useful where the existing floor is:
Lorient illustrates the LAS8007 si with the LAS4011 100mm threshold plate, although other suitable threshold plates may be used where permitted by the project and doorset specification.
Yes. Lorient recommends using the LAS8007 si with a suitable perimeter seal.
The drop seal treats the gap beneath the door, while the perimeter seals treat the:
Using both helps create a continuous sealing system around the complete door leaf.
Measure the door width and confirm that the door can safely accommodate a groove measuring 21mm wide and 44mm deep.
The LAS8007 si is supplied in fixed length increments and can only be shortened within Lorient’s stated cut-back limits.
Also check:
Do not route into a fire-rated, glazed, hollow or specialist door without first checking the door manufacturer’s instructions and certification.
Lorient LAS8007 si is a heavy-duty, fully mortised automatic drop seal with a self-levelling silicone gasket. It is installed within a machined groove along the bottom edge of a door.
| Product Name | Lorient LAS8007 si Drop Seal |
| Manufacturer | Lorient |
| Product Reference | LAS8007 si |
| Product Type | Automatic mortised door-bottom drop seal |
| Duty Classification | Heavy duty |
| Installation Type | Fully mortised |
| Related Product | Fully mortised version of the LAS8006 si |
| Application | Sealing the threshold gap beneath single and double swing doors |
| Operating Method | Mechanical actuator lowers the gasket as the door closes and retracts it when the door opens |
| Power Requirement | None — mechanically operated |
| Required Groove Width | 21mm |
| Required Groove Depth | 44mm |
| Approximate Gasket Width | 40mm according to the current profile drawing |
| Published Minimum Gap | 1mm |
| Published Maximum Drop | 15mm |
| Seal Material | Black or grey silicone rubber |
| Carrier Material | Aluminium |
| Self-Levelling | Yes — designed to adjust across slightly uneven floor or threshold surfaces |
| Adjustment | Actuator-button adjustment independent of the fixing screws |
| Adjustment Direction | Clockwise reduces movement; anti-clockwise increases movement |
| Door Types | Single swing, single-leaf and double-leaf doors |
| Door Handing | Suitable for right- and left-handed doors |
| Actuator Position | Hinge side of the door |
| Use With | Any suitable perimeter seal and any suitable threshold plate |
| Acoustic Test Standard | BS EN ISO 10140-1:2010+A2:2014, Annex J |
| Acoustic Test Evidence | Up to Rw 39dB within the relevant tested door assembly |
| Smoke Test Standard | BS 476-31.1:1983 at ambient temperature |
| Durability | Tested to 100,000 operating cycles |
| Containment Characteristics | Contributes towards sound, smoke, draught and light containment |
| Wheeled Traffic | Suitable; the gasket retracts when the door opens |
| Standard Finish | Silver anodised aluminium with grey end caps and grey silicone rubber gasket |
| Non-Standard Gasket and End Caps | Black end caps and black silicone gasket may be available subject to charges, minimum order quantities and additional lead times |
| Fixing Method | Screw-fixed through pre-drilled holes in the fixing flanges |
| Fixing Screws | Supplied |
| End Caps | Two end caps supplied |
| Striker Button | One striker button supplied |
| Certifire Reference | CF5179 |
| UL Certification Reference | R27972 |
| Positive-Pressure Classification | 5DL3 classification shown in the current fitting guide |
| Standalone Acoustic Rating? | No — Rw 39dB applies to a relevant tested complete door assembly |
| Standalone UK Fire Rating? | No standalone FD rating is stated in the current product datasheet |
| Supplied Length | Minimum Permitted Cut Length |
|---|---|
| 335mm | 275mm |
| 435mm | 335mm |
| 535mm | 435mm |
| 635mm | 535mm |
| 735mm | 635mm |
| 835mm | 735mm |
| 935mm | 835mm |
| 1035mm | 935mm |
| 1135mm | 1035mm |
| 1235mm | 1135mm |
The LAS8007 si must only be cut from the end opposite the actuator button.
Do not shorten the seal below the minimum cut-back length stated for the supplied size. Cutting it too short can interfere with the internal spring and operating mechanism.
When cutting the seal:
The LAS8007 si can be used on:
Lorient states acoustic test evidence of up to Rw 39dB in accordance with BS EN ISO 10140-1:2010+A2:2014, Annex J.
This figure applies to a complete tested door assembly and does not represent the independent sound reduction of the drop seal.
Final acoustic performance will depend on:
The current Lorient product information lists smoke-test evidence to BS 476-31.1:1983 at ambient temperature.
The drop seal must be used as part of a complete smoke-sealing arrangement. Suitable perimeter seals should be installed around the head and jambs of the door.
Final performance depends on the complete door construction and tested component arrangement.
The LAS8007 si is shown with Certifire reference CF5179 and UL classification reference R27972.
The fitting guide also states that the listed positive-pressure gasketing materials are intended for use with specified wood, composite and metal fire-door constructions.
These certification references must not be interpreted as an independent UK fire-resistance period for the drop seal.
For a fire-resisting door:
The LAS8007 si can operate directly against a suitable smooth floor or sill.
A threshold plate can provide more consistent contact where the existing surface is:
The selected threshold plate must be compatible with the available clearance, 15mm maximum drop and applicable doorset evidence.
Store the LAS8007 si:
Do not allow dust, timber chips or metal swarf to enter the internal mechanism.
Lorient LAS8007 si Drop Seal is fully mortised into a groove machined along the bottom edge of the door.
The seal should be positioned on the centre line of the door, with the actuator button at the hinge side.
The LAS8007 si must only be shortened from the end opposite the actuator button and must not be cut below Lorient’s stated minimum cut-back length.
Always check the current Lorient fitting guide and the evidence for the complete doorset before installation.
Inspect the door, frame and threshold before machining or fitting the seal.
Check that:
Do not machine a fire-rated, hollow, glazed or specialist door until the proposed groove has been checked against the door manufacturer’s evidence.
Remove the LAS8007 si from its packaging and identify:
The current cut-back limits are:
Do not cut the seal below the minimum length stated for the supplied size.
Remove the door from its hinges.
Lay the door securely on its side and restrain it so that it cannot move while being measured, routed or drilled.
Support the door across its full length to avoid:
If the bottom edge is already correctly grooved to suit the LAS8007 si, clean and inspect the groove before continuing to the measuring and cutting stages.
Measure and mark the seal position along the bottom edge of the door.
For optimum operation, Lorient instructs that the seal should be positioned on the centre line of the door.
Mark the complete routing area clearly.
Check that the proposed groove:
Fit a suitable long-series cutter to the router and set the guide.
Machine a continuous groove along the bottom of the door measuring:
Route the groove in controlled passes rather than attempting to remove the full depth in a single pass.
Keep the router stable and maintain a straight, consistent groove.
Use appropriate extraction to control dust and chips.
Remove all timber chips, dust and debris from the groove.
Measure the finished mortise to confirm that it is:
Dry fit the LAS8007 si housing to confirm that the fixing flanges sit correctly against the bottom edge of the door.
Measure the width of the door at the bottom edge.
Subtract the combined thickness of the supplied end plates before marking the aluminium seal for cutting.
The finished drop seal should fit neatly across the door without the end caps binding against the frame or stops.
Check the required finished length against the minimum cut-back size for the supplied seal.
At the end opposite the actuator button, carefully pull the silicone gasket away from the section that needs to be cut.
Move enough gasket away from the cutting position to prevent the saw from damaging it.
Do not:
Using a suitable power saw or hacksaw, cut the aluminium housing to the marked finished length.
Support the seal securely while cutting to prevent vibration or distortion.
After cutting:
Do not leave metal swarf inside the operating mechanism.
After cutting the external aluminium housing, the internal carrier must be shortened by a further 3mm.
Remove the small self-tapping screw from the top of the housing.
Slide the internal carrier slightly proud of the housing and mark the additional 3mm reduction.
Cut the carrier carefully, then:
The internal carrier must not project beyond the finished aluminium housing.
Push the silicone gasket back into its normal position.
Allow it to sit naturally without stretching or bunching.
Trim the gasket to the finished length using a sharp knife, scissors or suitable snips.
The gasket should finish neatly within the end-cap arrangement without being stretched tight or left excessively long.
Place the LAS8007 si into the machined groove.
Make sure the actuator button is positioned at the hinge side of the door.
Check that:
Use the pre-drilled holes in the fixing flanges to mark the pilot-hole positions on the bottom edge of the door.
Remove or hold the seal aside and drill suitable pilot holes using the 2.5mm drill bit specified in the current fitting guide.
The pilot-hole depth must suit:
Do not drill into concealed door hardware, glazing channels or structural components.
Return the LAS8007 si to the groove and secure it using the supplied screws.
Tighten the screws evenly through the fixing flanges.
Do not overtighten the fixings, as this could:
Check that the housing remains straight and firmly seated within the mortise.
Fit the supplied end caps to both ends of the seal.
Make sure each cap is fully seated and does not interfere with:
The end caps should finish neatly against the edges of the door.
Carefully return the door to its frame and refit it to the hinges.
Confirm that:
Fit the supplied striker button where required so that the actuator meets a suitable contact surface as the door closes.
Open and close the door while observing the silicone gasket.
The gasket should:
Check that the door continues to close and latch correctly.
Pull the actuator button clear of the housing to access the threaded adjustment.
Where the button is flush or recessed, use long-nose pliers to pull it out carefully.
Hold the threaded rod firmly and turn the actuator button:
Make small adjustments and test the door after each change.
For optimum performance, the silicone gasket should touch the sill or threshold during the final closing movement.
Close the door and inspect the gasket across its complete width.
Check that:
Where the floor is too uneven or soft, install a suitable threshold plate to provide a smoother sealing surface.
Open and close the door several times.
Confirm that:
Lorient recommends using the LAS8007 si with a suitable perimeter seal.
The perimeter seal treats the gaps around the:
The LAS8007 si 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 suitable threshold plate can provide a firm and level contact surface beneath the drop seal.
This is useful where the existing floor is:
The threshold plate must not reduce the available clearance below the operating requirements of the drop seal.
After installing the threshold plate, readjust the actuator so the gasket makes light and consistent contact during the final closing movement.
Inspect and test the LAS8007 si 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 or unapproved lubricants.
Readjust the actuator if the door settles, the hinges move or the threshold level changes.
Correct machining, cutting, positioning and adjustment are essential to the performance of the LAS8007 si.
The gasket should make continuous contact with the sill or threshold during the final closing movement, 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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