Fermacell Cross laminated timber walls
26 system references
Technical Library › Fermacell › Cross laminated timber walls
We are a supply and fit installation contractor, not the manufacturer. Information here is reproduced from manufacturers' literature for reference only; always confirm it directly with the manufacturer before specifying, ordering or installing.
fibre gypsum and Firepanel A1 linings to CLT walls, including cavity walls and firewalls, with load-bearing fire resistance (REI) and the K₂ encapsulation class that protects the timber from charring. Use the filter to narrow by performance or board.
| Reference | Build-up | Fire EN | Rw (dB) | Thickness (mm) | Load | Mass (kg/m²) | Encapsulation | |
|---|---|---|---|---|---|---|---|---|
| 1 HTM 11 | ≥ 100 mm wall. ≥ 80 mm cross laminated timber; 10 mm fibre gypsum each side. | REI30 | ≥ 37 | ≥ 100 | 160 kN/m | ≥ 60 | K₂10 | |
| 1 HTM 23 | ≥ 100 mm wall. ≥ 80 mm cross laminated timber; 10 mm fibre gypsum each side. | REI60 | ≥ 37 | ≥ 100 | 40 kN/m | ≥ 60 | K₂10 | |
| 1 HTM 24 | ≥ 130 mm wall. ≥ 80 mm cross laminated timber; 2 × 12.5 mm fibre gypsum each side. | REI60 | ≥ 41 | ≥ 130 | 160 kN/m | ≥ 96 | K₂30 | |
| 1 HTM 21 | ≥ 145 mm wall. ≥ 120 mm cross laminated timber; 12.5 mm fibre gypsum each side. | REI60 | ≥ 40 | ≥ 145 | 200 kN/m | ≥ 87 | K₂10 | |
| 1 HTM 22 | ≥ 172 mm wall. ≥ 120 mm cross laminated timber; 12.5 mm fibre gypsum (one side on resilient top hat 27 × 60 mm) each side; glass wool. | REI60 | ≥ 53 | ≥ 172 | 200 kN/m | ≥ 89 | K₂10 | |
| 1 HTM 34 | ≥ 130 mm wall. ≥ 80 mm cross laminated timber; 2 × 12.5 mm fibre gypsum each side. | REI90 | ≥ 41 | ≥ 130 | 40 kN/m | ≥ 96 | K₂30 | |
| 1 HTM 32 | ≥ 145 mm wall. ≥ 120 mm cross laminated timber; 12.5 mm fibre gypsum each side. | REI90 | ≥ 40 | ≥ 145 | 120 kN/m | ≥ 87 | K₂10 | |
| 1 HTM 33 | ≥ 172 mm wall. ≥ 120 mm cross laminated timber; 12.5 mm fibre gypsum (one side on resilient top hat 27 × 60 mm) each side; glass wool. | REI90 | ≥ 53 | ≥ 172 | 120 kN/m | ≥ 89 | K₂10 | |
| 1 HTM 31 | ≥ 180 mm wall. ≥ 120 mm cross laminated timber; 2 × 15 mm fibre gypsum each side. | REI90 | ≥ 44 | ≥ 180 | 200 kN/m | ≥ 129 | K₂45** | |
| 1 HTM 41 | ≥ 156 mm wall. ≥ 120 mm cross laminated timber; 18 mm fibre gypsum each side. | REI120 | ≥ 41 | ≥ 156 | 120 kN/m | ≥ 100 | K₂30 | |
| 1 HTM 42 | ≥ 180 mm wall. ≥ 120 mm cross laminated timber; 2 × 15 mm fibre gypsum each side. | REI120 | ≥ 44 | ≥ 180 | 150 kN/m | ≥ 129 | K₂45** | |
| 1 HTM 21 A1 | ≥ 100 mm wall. ≥ 80 mm cross laminated timber; 10 mm Firepanel A1 each side. | REI60 | ≥ 37 | ≥ 100 | 45 kN/m | ≥ 61 | K₂10 | |
| 1 HTM 41 A1 | ≥ 235 mm wall. ≥ 80 mm cross laminated timber; Firepanel A1 (printed as 12.5 (CW50) and 10) each side; 40/40 mineral wool. | REI120 | ≥ 71 | ≥ 235 | 45 kN/m | ≥ 95 | ||
| 1 HTM 12 | ≥ 190 mm wall. ≥ 2 × 80 mm cross laminated timber; 10 mm fibre gypsum each side. Cavity wall: two CLT leaves with 10 mm cavity (no insulation) or 100 mm cavity (80/10 mineral wool); Rw given as 10 mm / 100 mm cavity. Load is per wall side. | REI30 | ≥ 49 / ≥ 69 | ≥ 190 | 160 kN/m each wall side | ≥ 96 | K₂10 | |
| 1 HTM 25 | ≥ 190 mm wall. ≥ 2 × 80 mm cross laminated timber; 10 mm fibre gypsum each side. Cavity wall: two CLT leaves with 10 mm cavity (no insulation) or 100 mm cavity (80/10 mineral wool); Rw given as 10 mm / 100 mm cavity. Load is per wall side. | REI60 | ≥ 49 / ≥ 69 | ≥ 190 | 40 kN/m each wall side | ≥ 96 | K₂10 | |
| 1 HTM 26 | ≥ 220 mm wall. ≥ 2 × 80 mm cross laminated timber; 2 × 12.5 mm fibre gypsum each side. Cavity wall: two CLT leaves with 10 mm cavity (no insulation) or 100 mm cavity (80/18 mineral wool); Rw given as 10 mm / 100 mm cavity. Load is per wall side. | REI60 | ≥ 54 / ≥ 74.5 | ≥ 220 | 160 kN/m each wall side | ≥ 132 | K₂30 | |
| 1 HTM 27 | ≥ 275 mm wall. ≥ 2 × 120 mm cross laminated timber; 12.5 mm fibre gypsum each side. Cavity wall: two CLT leaves with 10 mm cavity (no insulation) or 100 mm cavity (80/10 mineral wool); Rw given as 10 mm / 100 mm cavity. Load is per wall side. | REI60 | ≥ 55 / ≥ 75 | ≥ 275 | 200 kN/m each wall side | ≥ 143 | K₂10 | |
| 1 HTM 35 | ≥ 220 mm wall. ≥ 2 × 80 mm cross laminated timber; 2 × 12.5 mm fibre gypsum each side. Cavity wall: two CLT leaves with 10 mm cavity (no insulation) or 100 mm cavity (80/18 mineral wool); Rw given as 10 mm / 100 mm cavity. Load is per wall side. | REI90 | ≥ 54 / ≥ 74.5 | ≥ 220 | 40 kN/m each wall side | ≥ 132 | K₂30 | |
| 1 HTM 36 | ≥ 275 mm wall. ≥ 2 × 120 mm cross laminated timber; 12.5 mm fibre gypsum each side. Cavity wall: two CLT leaves with 10 mm cavity (no insulation) or 100 mm cavity (80/10 mineral wool); Rw given as 10 mm / 100 mm cavity. Load is per wall side. | REI90 | ≥ 55 / ≥ 75 | ≥ 275 | 120 kN/m each wall side | ≥ 143 | K₂10 | |
| 1 HTM 37 | ≥ 310 mm wall. ≥ 2 × 120 mm cross laminated timber; 2 × 15 mm fibre gypsum each side. Cavity wall: two CLT leaves with 10 mm cavity (no insulation) or 100 mm cavity (80/18 mineral wool); Rw given as 10 mm / 100 mm cavity. Load is per wall side. | REI90 | ≥ 60 / ≥ 74.5 | ≥ 310 | 200 kN/m each wall side | ≥ 185 | K₂45** | |
| 1 HTM 43 | ≥ 286 mm wall. ≥ 2 × 120 mm cross laminated timber; 18 mm fibre gypsum each side. Cavity wall: two CLT leaves with 10 mm cavity (no insulation) or 100 mm cavity (80/18 mineral wool); Rw given as 10 mm / 100 mm cavity. Load is per wall side. | REI120 | ≥ 57 / ≥ 77 | ≥ 286 | 120 kN/m each wall side | ≥ 100 | K₂30 | |
| 1 HTM 44 | ≥ 310 mm wall. ≥ 2 × 120 mm cross laminated timber; 2 × 15 mm fibre gypsum each side. Cavity wall: two CLT leaves with 10 mm cavity (no insulation) or 100 mm cavity (80/18 mineral wool); Rw given as 10 mm / 100 mm cavity. Load is per wall side. | REI120 | ≥ 60 / ≥ 74.5 | ≥ 310 | 150 kN/m each wall side | ≥ 185 | K₂45** | |
| 1 HTM 22 A1 | ≥ 100 mm wall. ≥ 2 × 80 mm cross laminated timber; 10 mm Firepanel A1 each side. Cavity wall: two CLT leaves with 10 mm cavity (no insulation) or 100 mm cavity (80/10 mineral wool); Rw given as 10 mm / 100 mm cavity. Load is per wall side. | REI60 | ≥ 49 / ≥ 69 | ≥ 100 | 45 kN/m each wall side | ≥ 97 | K₂10 | |
| 4 HTM 32 | ≥ 146 mm firewall. ≥ 80 mm cross laminated timber; 15 + 18 mm fibre gypsum each side. Max. stress 3.0 N/mm²; flanking Dn,f,w ≥ 61 dB. | REI 90-M | ≥ 42 | ≥ 146 | 3.0 N/mm² | ≥ 117 | K₂60 | |
| 4 HTM 33 | ≥ 280 mm firewall. ≥ 80 mm cross laminated timber; inside 15 + 18 mm fibre gypsum, outside 160 mm STEICOprotect L dry + 6 mm STEICOsecure base. Max. stress 2.5 N/mm²; flanking Dn,f,w ≥ 61 dB. | REI 90-M | ≥ 36 | ≥ 280 | 2.5 N/mm² | ≥ 123 | K₂60 (from inside) | |
| 4 HTM 31 | ≥ 236 mm cavity firewall. ≥ 2 × 80 mm cross laminated timber with 10 mm cavity or 100 mm cavity (80/18 mineral wool); 18 + 15 mm fibre gypsum each side. Max. stress 3 N/mm² each wall side; Rw given as 10 mm / 100 mm cavity. | REI 90-M | ≥ 56 / ≥ 74.5 | ≥ 236 | 3 N/mm² each wall side | ≥ 152 | K₂60 |
System references, build-ups and performance figures are Fermacell's own data, reproduced here from fermacell Specification Guide for reference only, with credit to Fermacell.
Each reference links to Fermacell's page for the full, current specification - always specify from Fermacell's own documentation, HCI will not be held liable for a misspecification where this page has been used in lieu of the true manufacturer.
If you represent Fermacell and have a query pertaining to this library, please email info@howeceilings.co.uk. Data retrieved 10 October 2026.
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