What is a 35mm Flat Aluminium Door Threshold Strip?

A 35mm flat aluminium door threshold strip is a low-profile metal bar installed at the base of a doorway to create a clean, flush transition between two same-level floor surfaces. It protects exposed floor edges, covers expansion joints, and delivers a professional finish in both residential and commercial interiors. Unlike raised T-bar profiles, a flat threshold sits level with both floors — eliminating trip hazards and meeting UK Building Regulations guidance for accessible thresholds.

Technical Specifications

Choosing Your Length

Colour Matching Guide

Key Features and Benefits

• Flush flat profile — sits level with the floor, no raised lip, trip-hazard free. Compliant with BS 8300 accessible design guidance for thresholds not exceeding 15mm in height.
• Anodised aluminium construction — electrochemical anodising bonds a hard oxide layer to the surface. Result: scratch-resistant, corrosion-proof, maintenance-free. Outlasts painted or lacquered profiles by years.
• Pre-drilled fixing holes — no guesswork. Mark, drill, plug, screw. Screws and plugs included in every pack.
• Five premium finishes — match your door hardware, skirting boards, and floor trims precisely.
• Two lengths — 0.93m for standard doorways; 2.7m for wide-format openings with no join needed.
• Covers expansion joints — protects floating floor edges from dirt, lifting, and foot-traffic wear.
• Underfloor heating compatible — aluminium conducts heat freely; does not restrict UFH performance.
• Cut to any length — metal saw or angle grinder. File edges smooth. No specialist tools needed.

Where to Use a Flat Door Threshold Strip

Use a flat threshold wherever two floors meet at the same height:

• Hallway laminate → living room carpet
• Kitchen vinyl or LVT → dining room hardwood
• Bathroom tile → bedroom laminate
• Office reception tile → meeting room carpet tiles
• Hotel corridors and retail entrances
• Spanning expansion joints within a single floor type on long runs
• Conservatories and covered porches (anodised aluminium is corrosion-resistant)

⚠️ Important: If your two floors are at different heights, you need a ramp or reducer threshold — not a flat bar. This product is for same-level surfaces only.

How to Install — Step by Step

1. Measure the doorway width accurately with a tape measure.
2. Mark and cut the threshold strip to length using a metal saw or angle grinder. File any sharp edges smooth.
3. Position the strip centred over the floor joint or expansion gap, aligned with the door stop.
4. Mark fixing holes through the pre-drilled positions onto the subfloor.
5. Drill pilot holes and insert the supplied wall plugs.
6. Screw down using the supplied screws — firm but not overtightened, to allow natural floor movement.
7. Check finish — run your hand across; both surfaces should feel flush with no catching edge.

Installation time: approximately 15–20 minutes per doorway. Suitable for confident DIY and professional installation.

Frequently Asked Questions

What is the difference between a flat threshold strip and a T-bar transition?

A flat threshold strip (this product) screws directly to the subfloor and lies on top of both floor surfaces — creating a flush, permanent finish. A T-bar clips into a separate track and sits slightly raised, designed for floating floors that may need to be lifted. Flat strips are more secure, lower profile, and better suited to high foot traffic and commercial use.

Can this threshold strip be used on underfloor heating?

Yes. Aluminium conducts heat efficiently and will not restrict underfloor heating performance. Before drilling, always verify the location of any UFH pipes or cables using your heating layout plan to avoid penetrating them.

Can this threshold be cut shorter?

Yes. Both the 930mm and 2700mm lengths cut easily using a metal-cutting saw blade or angle grinder. Always cut from the undrilled end and file the cut edge smooth to remove burrs before installation.

What is the best colour for silver or chrome door handles?

Silver or Inox. Silver is brighter and more polished; Inox has a brushed stainless steel appearance. For brushed nickel handles, Inox or Champagne works best. For matte black handles, choose Black.

Is a 35mm threshold wide enough to cover my expansion gap?

Yes, for standard gaps. Most floating floors need an 8–12mm expansion gap. A 35mm threshold rests comfortably on both floor surfaces either side of any standard gap. For unusually wide gaps, consider a 50mm or 60mm profile.

Is this suitable for outdoor or wet areas?

Anodised aluminium is corrosion-resistant and suitable for covered external thresholds (conservatories, covered porches, indoor wet rooms). It is not designed for fully exposed outdoor use subject to standing water.

What is anodised aluminium and why does it matter?

Anodising is an electrochemical process that converts the surface of the aluminium into a hard, durable oxide layer. This makes it scratch-resistant, permanently coloured, and completely maintenance-free — unlike painted profiles which can chip, peel, or fade. Anodised thresholds last significantly longer in high-traffic areas.

How many strips do I need?

One strip per doorway with a floor transition or expansion gap. Standard UK doorways (762–838mm) are covered by the 930mm length with material to spare for cutting. Wide openings or commercial doorways may require the 2700mm length or two 930mm pieces joined at the centre.

Why Buy From Stair Nosings UK?

• ✅ UK stock — available for fast dispatch, no overseas waiting times
• ✅ Specialist flooring trims supplier — threshold strips, stair nosings, and floor profiles are our expertise
• ✅ Complete kit — screws and plugs included, ready to install out of the box
• ✅ 5 finishes, 2 lengths — the right size and colour for every project
• ✅ Trade and DIY — used by professional flooring installers and confident home improvers across the UK
• ✅ Secure checkout — major payment methods accepted

Available in Silver, Gold, Champagne, Inox, and Black. Lengths: 930mm and 2700mm. Screws and plugs included. Select your colour and length above.