The Premier Single 4 door threshold provides a neat and secure way to join thin carpets and natural flooring up to 4mm thick with floorboards and thin vinyl flooring. Featuring a smooth curved edge and available in a choice of 10 natural metal finishes, it creates a tidy, professional transition between floor coverings.
Description
The Premier Single 4 is designed for joining stick-down carpets and natural sisal up to 4mm thick to floorboards and thin vinyl flooring. The curved profile creates a smooth transition between the two floor coverings, while helping to conceal raw edges for a neat finish.
The carpet is held securely under tension by integrated teeth, while the adjoining floor covering sits beneath the curved edge. The threshold is designed for use on level floors and should lie flat once installed.
Manufactured from solid brass with rounded edges, the Premier Single 4 is available in a choice of 10 unlacquered metal finishes. It is also known as the Premier Trim Single or a Single Naplock.
If you are fitting a standard thickness carpet, the Premier Single 9 is recommended instead.
Key Features
- Designed for joining thin carpets and natural sisal up to 4mm thick
- Suitable for joining to floorboards and thin vinyl flooring
- Smooth curved edge for a neat transition
- Carpet is secured using integrated teeth
- Suitable for level floors
- Solid brass construction with rounded edges
- Available in a choice of 10 unlacquered metal finishes
- Available in 900mm, 1000mm, 1800mm and 2700mm lengths
- Also known as a Premier Trim Single or Single Naplock
Sizing Specifications
Available lengths:
- 900mm
- 1000mm
- 1800mm
- 2700mm
Can be cut to size using a sharp hacksaw.
Important: Suitable for thin carpets and natural sisal up to 4mm thick only. The underlay should stop short of the door threshold.
Flooring Compatibility
Compatible with:
- Stick-down carpet up to 4mm thick
- Natural sisal up to 4mm thick
- Floorboards
- Thin vinyl flooring
Not suitable for:
- Standard thickness carpet (use the Premier Single 9 instead)
- Cut the threshold to the required length using a sharp hacksaw.
- Fix in place using a proprietary adhesive, nails or screws, avoiding areas where underfloor heating is present.
- Ensure the underlay stops short of the threshold. Once fitted, the carpet can be 'napped down' using a carpeted wood block to provide an extra firm grip on the pins and reduce the carpet height further.
How to Install a Door Threshold Step-by-Step
Installing a Premier Square door threshold is straightforward:
- Measure the doorway and cut the door bar to size using a hacksaw.
- Position the threshold where the carpet meets the hard floor.
- Fix the trim using adhesive, nails, or screws (avoiding underfloor heating).
- Ensure the carpet edge is positioned correctly against the pins.
- Press the carpet into place so it is gripped securely.
- Use a carpeted wood block to ‘nap down’ the trim for a tighter fit if required.
- Check the trim sits evenly and securely across the join.
- For more help, see our guides on installing door threshold strips and cutting door bars to size.
How to Remove an Existing Door Threshold
- To remove an existing door threshold, first identify how it has been fixed.
- If secured with screws, carefully remove them using the correct screwdriver. For nails, use a claw hammer or pry bar to gently lift the trim.
- Release the carpet edge from the pins before removing the threshold. Take care to avoid damaging the carpet or surrounding flooring.
- Clear away any remaining fixings or debris before installing your new door threshold strip.
Cleaning & Maintenance
- Clean using a soft cloth and mild cleaning solution.
- This product is manufactured from solid brass and hand-finished, so the finish may vary slightly between batches. As it is unlacquered, it may naturally age over time depending on its environment.
For further advice, see our guide to cleaning door thresholds.
Delivery Information
Free UK delivery is available on all orders over £100.
Many of our door thresholds and flooring trims are eligible for next-day delivery. This will be shown on the product page and again during checkout.
We deliver across Great Britain for most items, including Northern Ireland.
Orders are dispatched directly from our manufacturers using trusted couriers. As many products are hand-finished or made to order, delivery times may vary. Estimated delivery information is shown on each product page, with further details available on our Delivery page.
Frequently Asked Questions
What is the Premier Single 4 used for?
It is designed to join thin stick-down carpets and natural sisal up to 4mm thick with floorboards and thin vinyl flooring.
What carpet thickness is it suitable for?
It is suitable for carpets and natural sisal up to 4mm thick.
Can it be used with standard thickness carpet?
No. For standard thickness carpet, the Premier Single 9 is recommended.
Can it be cut to size?
Yes, it can be cut to length using a sharp hacksaw.
How is the carpet secured?
The carpet is gripped under tension by integrated teeth, while the adjoining floor covering sits beneath the curved edge.
Can it be fitted with adhesive?
Yes. It can be fixed using a proprietary adhesive, nails or screws.
Does the underlay go beneath the threshold?
No. The underlay should stop short of the door threshold.
How do I maintain the finish?
Clean with a soft cloth and mild cleaning solution. As the brass is unlacquered, it may naturally age over time.
