Lorient LAS8008 si Drop Seal is a slimline, face-fixed automatic door-bottom seal designed to reduce sound, smoke, draught and light transfer through the gap beneath a door.
The LAS8008 si features a curved aluminium cover plate that conceals the fixings and gives the installed seal a clean, finished appearance. It is particularly suitable for upgrading existing doors because it is fixed directly onto the face of the door rather than being mortised into the bottom edge.
Its spring-loaded mechanical system automatically lowers the silicone gasket as the door closes and lifts it away from the floor when the door opens. No electrical connection is required.
The LAS8008 si is installed along the bottom face of a door to seal the gap between the door leaf and the floor or threshold.
Unsealed gaps beneath doors can allow sound, smoke, draughts and light to pass between adjoining rooms. The LAS8008 si closes this gap automatically when the door shuts, while retracting when the door opens to reduce contact with the floor.
It is commonly used for:
The LAS8008 si contains a mechanical drop-seal system operated by an actuator button positioned at the hinge side of the door.
As the door closes, the actuator button meets the door stop. This activates the internal mechanism and lowers the flexible silicone gasket onto the sill, floor 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 small amount of door movement.
This helps reduce:
The mechanism is self-levelling, helping the gasket make contact across floors that are not completely even.
The LAS8008 si is a face-fixed-only drop seal.
It is mounted onto the lower face of the door on the stop side. Unlike a mortised drop seal, it does not require a deep channel to be routed into the bottom edge of the door.
This makes it particularly suitable for:
The curved aluminium cover plate slides over the fixing housing after installation, concealing the screws and internal carrier.
The LAS8008 si has been acoustically tested to BS EN ISO 10140-2:2010, with Lorient stating performance of up to Rw 30dB within the relevant tested door assembly.
The quoted acoustic figure applies to the complete tested doorset and sealing arrangement. It is not a standalone 30dB rating for the LAS8008 si itself.
Final acoustic performance will depend on:
For effective acoustic containment, the head and jambs should also be fitted with suitable acoustic perimeter seals.
The LAS8008 si has smoke-test evidence to:
The drop seal can contribute towards smoke containment by closing the otherwise open gap beneath the door.
It should be combined with suitable perimeter smoke seals around the head and jambs. The final smoke performance will depend on the complete doorset construction and tested component arrangement.
Lorient’s current technical datasheet lists fire-test evidence to BS EN 1634-1:2014+A1:2018 for FD30 and FD60 applications.
This does not mean that the LAS8008 si independently provides 30 or 60 minutes of fire resistance.
The stated performance applies only when the product is installed as part of an appropriate tested or assessed fire-resisting door assembly.
Before installing the LAS8008 si on a fire door, confirm:
The LAS8008 si is designed to self-level when it operates.
The gasket begins to lower from the hinge side and adjusts across the width of the doorway as the door reaches its closed position.
This helps provide consistent contact where the sill or floor is slightly uneven.
The operating height can be adjusted using the actuator button independently of the fixing screws.
Lorient states a published minimum and maximum operating gap of:
For installation, Lorient’s current fitting guide instructs the installer to position the seal with a gap of between 3mm and 10mm between the bottom of the door and the sill.
The exact adjustment should allow the silicone gasket to touch the sill during the final closing movement without excessive compression.
The LAS8008 si is suitable for:
The actuator button must be installed at the hinge side so that it meets the door stop as the door closes.
Suitable applications can include:
Yes. Lorient states that the LAS8008 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 has:
Lorient illustrates the LAS8008 si with the LAS4011 100mm threshold plate, but other suitable threshold plates may be used where permitted by the project specification.
Yes. Lorient states that the LAS8008 si can be used with any suitable perimeter seal.
The drop seal treats the threshold gap, while perimeter seals treat the head and jambs.
Using both helps create a more continuous sealing system around the complete door leaf.
Measure the distance between the door stops before selecting a length.
The LAS8008 si is supplied in fixed length increments and can only be shortened within the limits stated by Lorient. Cutting the seal below its permitted cut-back length can damage or prevent the internal mechanism from operating correctly.
Also check:
Drop seals shorter than 635mm use a single-spring mechanism and may not operate correctly until they are fully fitted and being activated by the closing door.
Lorient LAS8008 si is a slimline, face-fixed automatic drop seal with a curved aluminium cover plate and flexible silicone rubber gasket.
| Product Name | Lorient LAS8008 si Drop Seal |
| Manufacturer | Lorient |
| Product Reference | LAS8008 si |
| Product Type | Automatic face-fixed door-bottom drop seal |
| Installation Type | Face-fixed only |
| Application | Sealing the threshold gap beneath single and double swing doors |
| Operating Method | Mechanical actuator lowers the gasket when the door closes and retracts it when the door opens |
| Power Requirement | None — mechanically operated |
| Cover Design | Curved aluminium cover plate concealing the fixing housing |
| Approximate Profile Width | 14mm |
| Approximate Cover Height | 65mm |
| Published Minimum Gap | 1mm |
| Published Maximum Drop | 13mm |
| Installation Gap in Current Fitting Guide | Position with 3mm to 10mm between the door bottom and sill |
| Seal Material | Silicone rubber |
| 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 10140-2:2010 |
| Acoustic Test Evidence | Up to Rw 30dB within the relevant tested door assembly |
| Smoke Test Standards | BS EN 1634-3:2004 at ambient temperature and BS 476-31.1:1983 |
| Fire Test Standard | BS EN 1634-1:2014+A1:2018 |
| Fire Test Evidence | FD30 and FD60 within relevant tested or assessed door assemblies |
| Containment Characteristics | Contributes towards sound, smoke, draught and light containment |
| Wheeled Traffic | Suitable; 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 |
| Other Colour Finishes | Powder-coated finishes may be available as non-standard options; confirm current availability before ordering |
| Fixing | Screw-fixed through holes drilled in the aluminium housing at installation |
| Fixing Screws | Supplied |
| End Caps | Two end caps listed in the current fitting guide |
| Striker Button | One striker button supplied for timber-frame installations |
| Short-Length Mechanism | Lengths below 635mm use a single spring and operate correctly only when fully fitted and in use |
| Standalone Acoustic Rating? | No — Rw 30dB applies to a relevant tested complete door assembly |
| Standalone Fire Rating? | No — FD30 and FD60 performance depends on the complete tested or assessed doorset |
| Supplied Length | Minimum Permitted Cut Length |
|---|---|
| 335mm | 255mm |
| 435mm | 335mm |
| 535mm | 435mm |
| 635mm | 535mm |
| 735mm | 635mm |
| 835mm | 735mm |
| 935mm | 835mm |
| 1035mm | 935mm |
| 1135mm | 1035mm |
| 1235mm | 1135mm |
The LAS8008 si must only be cut from the end opposite the actuator button.
Do not cut a supplied length below its stated minimum cut-back size. Cutting the seal too short can interfere with the internal spring and operating mechanism.
When calculating the finished aluminium length, Lorient instructs installers to measure between the door stops and deduct 6mm to allow for the end caps and operating clearance.
The LAS8008 si can be used on:
Lorient states acoustic test evidence of up to Rw 30dB in accordance with BS EN ISO 10140-2:2010.
This figure applies to a complete tested door assembly and does not represent the independent sound reduction of the drop seal.
Final performance will depend on:
The current Lorient datasheet lists:
These results apply to relevant tested component and doorset arrangements.
Do not assume that the LAS8008 si can be added to any existing fire door without checking the door manufacturer’s certification, assessment or installation instructions.
The LAS8008 si can operate directly against a suitable smooth sill or floor surface.
A threshold plate may be used to provide more consistent contact where the existing surface is:
The selected threshold plate must be compatible with the door clearance, drop range and doorset evidence.
Store the LAS8008 si:
Do not attempt to operate short single-spring seals by hand before they are fully installed, as Lorient states that seals below 635mm operate correctly only when fitted and in use.
Lorient LAS8008 si Drop Seal is face-fixed onto the lower face of the door on the stop side.
The actuator button must be positioned at the hinge side so that it meets the door stop as the door closes.
The seal must be cut only from the end opposite the actuator button and must not be shortened 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 cutting or fitting the seal.
Check that:
Lorient’s fitting guide instructs the installer to position the seal with a gap of between 3mm and 10mm between the bottom of the door and the sill.
Remove the LAS8008 si from its packaging and identify:
Do not cut the seal until its supplied length and minimum permitted size have been checked.
The cut-back limits are:
Cutting the seal below the stated size can prevent the internal mechanism from operating correctly.
Measure the distance between the two door stops at the bottom of the doorway.
Take the measurement at the exact height and position where the LAS8008 si will be installed.
Deduct 6mm from the measured distance to allow for the end caps and operating clearance.
Mark the finished cut length onto the end opposite the actuator button.
Check the measurement before cutting.
At the end opposite the actuator button, carefully pull the silicone gasket back from the area 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 and cover sections to the marked length.
Support the seal securely while cutting to prevent vibration or distortion.
Cut only from the end opposite the actuator button.
After cutting:
Metal swarf must not be left inside the mechanism.
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 pulled tight or left excessively long.
Separate the curved aluminium cover plate from the fixing housing by sliding it lengthways.
Place the cover somewhere clean and protected to prevent scratching or bending.
The internal aluminium housing must be exposed so that it can be drilled and screw-fixed to the door.
Fit one end cap onto the actuator-button end of the aluminium housing.
Lorient instructs that the end cap should be secured using a plastic mallet.
Tap the cap carefully into place without:
In high-traffic areas or where the end cap may be exposed to impact or abuse, Lorient recommends securing it with a small amount of suitable high-strength adhesive applied to the locating prongs.
Place the LAS8008 si against the bottom face of the door on the stop side.
Position the actuator-button end tightly towards the hinge-side door stop.
Confirm that:
Temporarily hold or clamp the housing securely while marking and drilling the fixing positions.
Mark suitable fixing positions along the exposed aluminium housing.
Drill fixing holes through the housing using the drill sizes and spacing appropriate to the supplied screws and current Lorient fitting guide.
Distribute the fixings along the seal so that the housing will remain straight and firmly secured.
Take care not to drill into:
Remove all drilling debris before fixing the seal.
Hold the drilled housing in its final position and transfer the fixing-hole locations onto the door.
Drill suitable pilot holes into the door.
The drill depth and pilot-hole size must suit:
Do not drill into concealed door hardware, glazing channels or structural components without confirming that it is safe to do so.
Position the aluminium housing back onto the door and secure it using the supplied screws.
Tighten the screws evenly so that the housing remains straight.
Do not overtighten the fixings, as this could:
Check that the housing is secure and that the actuator button can move freely.
Slide the curved aluminium cover plate back over the fixed housing.
The cover should conceal the fixing screws and sit neatly against the door face.
Check that it:
Fit the remaining end cap and finishing plug at the cut end of the drop seal.
Make sure the end cap is fully seated and does not interfere with the silicone gasket.
Where the installation is in a high-traffic or vulnerable area, consider securing the end cap using a suitable adhesive in accordance with Lorient’s guidance.
For timber frames, position the supplied striker button onto the door stop where the actuator button makes contact as the door closes.
Align the striker so the actuator button meets it directly rather than contacting the stop at an angle.
The striker should:
Open and close the door while observing the gasket.
The gasket should:
Short seals below 635mm use a single spring and may only operate correctly once fully fixed and activated by the door.
Adjust the gasket movement by turning the actuator button:
Make small adjustments and test the door after each change.
For optimum results, Lorient states that the silicone gasket should touch the sill during the final closing movement of the door.
Avoid excessive drop or compression.
Too much movement can:
Close the door and inspect the gasket across the complete width.
Check that:
Where the floor is unsuitable or inconsistent, install an approved threshold plate to provide a smoother contact surface.
Open and close the door several times.
Confirm that:
Lorient recommends using the LAS8008 si with a suitable perimeter seal.
The perimeter seal should close the gaps around the:
The LAS8008 si then closes 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 surface beneath the drop seal.
This is useful where the existing floor is:
The threshold plate must not reduce the available door clearance below the permitted installation range.
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 LAS8008 si periodically as part of the door’s normal maintenance programme.
Check for:
Clean the gasket and threshold using a soft cloth and suitable mild cleaning product.
Avoid lubricants, abrasive tools or aggressive chemicals unless specifically approved by Lorient.
Readjust the actuator if the door settles, the hinges move or the threshold level changes.
Correct cutting, positioning and adjustment are essential to the performance of the LAS8008 si.
The gasket should make continuous contact with the sill during the final closing movement but 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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