Partition Wall — Ceiling Mount

Junction function

Top edge of the partition wall — UW profile (item 01) fixed to the slab. Critical element: sliding tape (item 08) between the UW profile and the slab.

Why a sliding tape?

• Reinforced concrete slabs deflect under live load (deflection ~L/250-L/300 = several mm for residential rooms).
• Without the tape: the UW profile wedges into the slab, the wall carries load against the designer’s intent → cracking of plaster, gypsum, plasterboard joints.
• With the tape: the profile slides relative to the slab — the wall remains unloaded, no cracks.

This is a detail costing ~PLN 5/lm (sliding tape) that eliminates 90% of partition wall cracks within the first 2 years of use.

Critical installation aspects

• UW profile (item 01) with width matched to wall thickness (UW 50/75/100 corresponds to wall widths of 60/85/110 mm).
• Sliding tape (item 08) — bonded to the slab before profile installation. Typical material: bituminous, ~3 mm thick, low friction.
• Expansion anchors (item 07) — unlike for load-bearing walls, a partition wall is fixed at 800-1000 mm spacing (not 300-400 mm). Fixing is free, not press-fit.
• Sealing tape (item 06) around the perimeter of the UW profile on the slab side — seals the acoustic gap (mandatory for acoustic walls).
• Vertical CW profile (item 02) inserted into the UW with 10 mm clearance at the top — does not contact the upper profile. The clearance enables UW profile movement.
• termPIR AL/WS thermal insulation (item 03) between CW profiles — eliminates thermal bridge + provides acoustic insulation (Rw ~45 dB for CW 100 + termPIR 40 mm).

Acoustic partition — Rw

Stud partition wall with termPIR AL 40 mm + 2× plasterboard on a CW 75 framework:

• Rw ≈ 47 dB (class A1 building acoustics, sufficient for apartments).
• Without termPIR: Rw ≈ 35 dB (drastic loss of sound insulation).

For open-space offices: add a second plasterboard layer + double framework (two independent CW 75 layers) → Rw ~55 dB.

Used in the intermediate floor slab termPIR AL system.

Documentation

termPIR Catalogue — Single-family Houses, p. 60 — partition walls, ceiling mount.

Components in this junction