Stair tread bolt Set 9A XXL with acoustic isolation, for mortar anchoring in brick

Stair tread bolt Set 9A XXL – concealed fixing with acoustic isolation

LamiFIX stair tread bolt Set 9A XXL connects grooved treads to the side of a brick wall. The connection is discreet and almost invisible in the groove. Each tread can be removed individually.

Application and design

Mortar anchoring in brick with an acoustic plug, tubular sleeve and mesh sleeve. Drilling depth 128 mm, wall hole Ø32 mm. Version A is suitable for straight stairs or in combination with a tread suspension system. Versions B or C are intended for winding stairs.

Installation with acoustic isolation is recommended for apartment buildings. For single-family homes, it can generally be omitted.

Accurate drilling and installation

Our drill bushes guide the drill bit accurately in angle and position throughout the drilling depth. Predrill at Ø16 mm with light hammer action, then finish at Ø32 mm without hammer action to avoid breaking the internal webs of the brick. Tip: rebar drill bits are particularly suitable for drilling brick without hammer action. The stair tread bolt must have at least 55 mm of support in the brick. Please consult us for insulating and lightweight blocks.

For drilling the holes, we lend matching bushes free of charge for up to three months. Installation is shown in the LamiFIX catalogue on page 26 . Drill bits LF 2060.160.3 (Ø16 mm) and LF 2070.320.3 (Ø32 mm) are available separately.

Installation tip: fit treads from top to bottom

This keeps the fixing screws underneath the treads accessible.
Clean the holes and insert the mesh sleeves. Then install each tread individually:

1. Fill the mesh sleeve with mortar from back to front: 1/7 cartridge per Set.
2. Insert the anchor with a twisting motion to distribute the mortar around it.
3. The easiest method is to fit the wooden tread or a temporary tread immediately and screw it to the anchor while the mortar is still workable.

At 20 °C, our mortar provides approximately two minutes more working time than a high-speed mortar – enough to install one tread.

Required quantity per Set

• 1 type A/B stair anchor, T=78 mm, M10, LF 3623.102.1
• 1 LamiFIX M10 connector, LF 35.M10x30 (catalogue LF 1035.130)
• 1 raised countersunk screw 5.5 × 32 mm, LF 1541.002.1
• 1 acoustic plug LF 1620.016.1
• 1 tubular sleeve Ø27 × 110 mm, LF 1621.110.1
• 1 mesh sleeve Ø32 × 128 mm, LF 1710.033.1
• 1 wall rosette LF 1801.025.1
• 1/7 cartridge of anchoring mortar LF 1720.002.1
• 1/5 adjustment washer LF 3605.002.1 for an 18–24 mm gap; each whole washer includes 1 long cover sleeve LF 3601.001.1 (26 mm)
• 1/100 threadlocker LF 3806.243.1

Ordering and sales units

The component list shows the quantities required per Set. Screws are supplied in packs, mortar in whole cartridges and threadlocker in whole tubes. Final quantities depend on the number of Sets.

Article number: LF 3623.109.4
For 100 Sets or more: LF 3623.109.6
Drilling depth 128 mm