SANS 10400-XA Walls — R & CR Compliance

Calculates total R-value, surface density, and CR-value; checks against the zone requirements in Table 6 (≥270 kg/m²) and Table 7 (<270 kg/m²). Includes metal framing thermal-break and Category 1 single-leaf thickness checks.

1) Project & Compliance Context

Min 0.20 m²·K/W required between metal elements.
Must be ≥140 mm when Cat 1 single-leaf masonry.

2) Wall Assembly (inside → outside)

Add layers. For each layer set thickness (mm), conductivity k (W/m·K), density ρ (kg/m³), and specific heat c (kJ/kg·K). The calculator sums R, surface density (Σρ·t), and areal heat capacity (Σρ·t·c).
Layer t (mm) k (W/m·K) ρ (kg/m³) c (kJ/kg·K) R (m²·K/W) mass (kg/m²) C (kJ/m²·K)

3) Results & Compliance

Total R (incl. Rsi/Rse)
Surface density Σ(ρ·t)
— kg/m²
Areal heat capacity Σ(ρ·t·c)
— kJ/m²·K
CR-value (h)
— h
Classification:
Zone requirement:
Result:
Metal framing thermal-break (≥0.20):
Cat 1 single-leaf masonry thickness (≥140 mm):
If metal framing/sheets are present, SANS 10400-XA requires a thermal break with R ≥ 0.2 m²·K/W between metal elements. For Category 1 single-leaf masonry, nominal thickness must be ≥140 mm.
Table 6 & 7 zone thresholds implemented per SANS 10400-XA 2021. Heavy wall (≥270 kg/m²) uses R-value only; Light wall (<270 kg/m²) may comply via R-value or CR-value.