Thresholds
An extruded aluminium section fixed to the floor across the opening, giving the door bottom seal a flat bearing surface, covering the junction between two floor finishes and holding back water from outside. Profiles include saddle, half saddle, water-return and low flat sections for accessible routes or vehicle traffic.
2 products
- Aluminium threshold with stop, 100 x 14.8 mm, tube sealRequest a quote
Frequently asked questions
Should I choose a saddle, half saddle or flat threshold?
A saddle threshold has two symmetrical bevels, for openings with the same floor level on both sides. A half saddle has one bevel, for a change in floor level or where the threshold butts against the frame stop. A low flat section suits routes used by trolleys, pallet trucks or wheelchair users.
What do I measure to order a threshold?
You need the length between the frame jambs, the frame depth (to choose a width that runs from one face of the frame to the other), and the height difference between the floors on each side. If the jambs have a stop, the threshold ends need notching to fit around the frame profile.
How does a water-return threshold differ from a standard one?
A water-return threshold has an upstand on the inside edge that acts as a stop for the door bottom seal and stops wind-driven water passing the gap. It suits outward-opening doors exposed to rain; on routes with frequent vehicle traffic the upstand is easily damaged, so consider a flat section combined with a door sweep.
What should I watch for when fixing an aluminium threshold to concrete?
Run a bed of sealant under the threshold and around the screw heads before fixing, otherwise water travels along the underside into the building. Use anchors suited to concrete, and on floors with heating pipes or a waterproof membrane, check drilling positions first.
What does ANSI/BHMA A156.21 cover?
ANSI/BHMA A156.21 is the BHMA standard for thresholds. It classifies the product family; where a project requires compliance, check the specific clauses against the technical data for the item rather than relying on the category name alone.
What finishes do aluminium thresholds come in, and how should I choose?
Aluminium thresholds are commonly mill finish, clear anodised or bronze anodised, usually with a fluted anti-slip top. On busy routes with trolleys, anodising resists wear better than mill finish but still wears gradually at the centre. For damp or chemical areas, consider a stainless steel threshold.
Can a threshold take forklift traffic?
Standard aluminium thresholds are designed for pedestrians and hand trolleys, not concentrated forklift wheel loads. Openings used by powered forklifts or pallet trucks need a heavy-duty threshold with a thicker section, fully bedded underneath in mortar so it cannot deflect. A deflected threshold opens a gap at the door sweep and cracks at the screw positions.
When should a threshold be replaced?
Replace it when the top has worn smooth with no anti-slip flutes left, when it is cracked or its screws are loose, or when water ponds or leaks inside even though the door sweep is sound. Thresholds with a replaceable rubber insert often need only the insert changed. Before removing it, photograph the profile at the end of the threshold to match the replacement.
