tch: Timber Charring
Start-of-charring calculation for planar timber members protected by one or more layers according to EN 1995-1-2:2026.

Main use cases
- Protected CLT and other planar timber members
- Comparison of cladding and insulation build-ups
- Determination of t_ch for subsequent timber fire design
Main features
Protection build-up
Define only the layers between the fire and the timber member, in order from the exposed side.
Orientation-aware method
Account for vertical, underside, or top-side exposure together with material, thickness, density, and joint details.
Charring start result
Calculate the total protection time t_ch and inspect the contribution and adjustment assigned to every layer.
Supported inputs
- Wall, floor, or ceiling orientation
- Protective layer sequence
- Layer material and thickness
- Panel-joint configuration
- Density and material-specific properties
Results generated
- Start time of charring t_ch
- Protection time of each layer t_prot,i
- Layer interaction increments Delta t_i
- Material and layer calculation trace
Available results and exports
WEBLayer-by-layer protection summary
PDFDetailed calculation report