Bottom fastening

The Strofix bottom fastening is an AISI 304 stainless-steel lightweight base plate for the 40 × 40 mm square railing post tube, available in two plate sizes: 100 × 100 or 80 × 80 mm. All variants share a 4 mm plate thickness (h) and two bolt holes. The bolt hole diameter depends on the plate size: Ø11 mm (for M10 bolts) on the 100 × 100 mm plate, or Ø9 mm (for M8 bolts) on the 80 × 80 mm plate. Supplied with a raw (unfinished) surface. The post tube is attached by welding (elements for welding included).

The two-bolt configuration with 4 mm plate thickness provides the simplest and most minimal base plate option in the Strofix range for the 40 × 40 mm post. The two fixing points are sufficient for light-duty residential railing installations where the structural engineer confirms the loading allows a two-bolt arrangement. The 80 × 80 mm plate provides a compact footprint; the 100 × 100 mm plate provides a larger bearing area. Select the plate size in the dropdown at order time.

The raw surface finish is standard for base plates concealed by a decorative cover after installation.

Use cases:

• Minimal two-bolt floor mounting for 40 × 40 mm square railing posts
• Light-duty residential railing and balustrade installations
• Compact 80 × 80 mm base plate where minimal footprint is required
• Two-bolt anchor configurations where space or site constraints limit fixing positions
• Budget base plate option for standard residential projects

FAQ:

What plate sizes are available?

Two plate sizes: 100 × 100 mm and 80 × 80 mm. Select in the dropdown at order time.

What bolt size does each plate accept?

The 100 × 100 mm plate has Ø11 mm bolt holes (for M10 bolts). The 80 × 80 mm plate has Ø9 mm bolt holes (for M8 bolts). Both variants have two bolt holes.

How does this differ from the 4-bolt lightweight base plate?

Both have the same 4 mm plate thickness for the 40 × 40 mm post. This product has 2 bolt holes; the 4-bolt version (SKU SP-4010544) has 4 bolt holes and is available in three plate sizes (80 × 80, 100 × 100, 105 × 105 mm). Choose based on the number of anchor points specified by the structural design.

What is the plate thickness?

All variants have a 4 mm thickness (h = 4 mm).

How is the post tube attached?

The post tube is welded to the base plate using TIG or MIG welding.

Why is the surface finish "raw"?

Base plates have a raw finish because they are typically concealed by a decorative cover after installation.

About Base & Clamp Fastenings

A base or clamp fastening is a stainless-steel plate or bracket that anchors a railing post to the building structure, forming the structural foundation of the balustrade. Bottom fastenings bolt to the top of a floor slab, deck or beam, while side fastenings bolt to the vertical face of a fascia, edge beam or wall. Assembly clamps grip an existing tube or post without welding, and assembly plates provide a flat mounting surface for auxiliary connections.

Strofix supplies 18 base and clamp products for Ø42.4 mm round pipe and 40×40 mm flat-sided square posts, with plate diameters from Ø80 to Ø100 mm (round) and plate dimensions from 80×80 to 135×56 mm (rectangular/square), in satin or raw-surface stainless steel with AISI 304 and AISI 316 options.

Screw-hole configurations include 2, 3 and 4-hole variants. The correct fastening depends on mounting orientation, post profile, plate size, number of screw holes and the required surface finish.