Underfloor Insulation
USA R measurements are 5.68 times larger than those expressed in metric (SI) units due to Imperial v Metric units.
Use PVA or Aliphatic glue to:
- Polystyrene joints
- Kopine to polystyrene
- Kopine joints.
Maximum U-value of 0.13W/m2K for the floor (UK) R7.7
Soil conductivities can range from as low as 0.5W/m °C for very dry soil R=2.0, through 1.2W/m °C for average soil, to as high as 2.0W/m °C for wet soil. R=0.8 for average soil
Approximately 10-15% of the heat loss is through the ground floor, 80% leaks through perimeters.
Expol Platinum Board delivers an R-value of R 0.77/25mm $8.60/m2 – CHEAPEST (Get 50mm)
XPS: ezisteel.co.nz/products/thermal-break
- XPS is often selected over EPS for wetter environments that require a higher water vapor diffusion resistance value
- The compressive strength of XPS is greater than that of EPS
Kopine R0.17 m2K/W (R=1)
R7.7 for: dry soil, (R2), Particleboard (R1) and 150mm Expol Platinum (R4.69). $16k extra
R6 for: dry soil, (R2), Particleboard (R1) and 65mm Expol Platinum (R3). Total heat loss (0.284W/K): 284
R5.3 for: dry soil, (R2), Particleboard (R1) and 50mm Expol Platinum (R2.29). Total heat loss (0.295W/K): 295
R4.58 for: dry soil (R2), Particleboard (R1) and 35mm Expol Platinum (R1.58). Total heat loss (0.307W/K): 307
Kw/day – 2 hours in morning, 6 in evening. 9 hours @30c/kW = $2.70
5000BTU/hr (0.4 ton, 1.4kW) sensiblehouse.org/nrg_heatloss.htm = $1.15/day
.38+3.75=4.13 * 83sqm
3.75 *
