Lambda values for EPS, XPS and mineral wool
Read product lambda, declared and design values. Compare documented EPS, XPS and mineral wool examples and calculate layer R correctly.
Read guideGuided project
Thermal insulation
Work from entered thermal values to insulation quantity estimates with stated limits.
Use documented values and layers, then convert measured coverage into insulation packages.
Your project workflow
Work from top to bottom. Optional steps can be skipped; alternatives are grouped into one decision.
Check completed steps. You can skip optional steps.
- 1
Optional
Convert R and U values
Use this when product data use a different thermal-value convention.
Use R-value to U-value calculator - 2
Step 2
Check entered layers
Combine entered layer data into a bounded resistance estimate.
Use Layered thermal resistance - 3
Step 3
Estimate insulation thickness
Use target and entered material data for a quantity-oriented thickness estimate.
Use Insulation thickness calculator - 4
Step 4
Calculate insulation packs
Convert measured coverage and pack data into whole packs.
Use Insulation packs - 5
Optional
Review dew-point tool limits
Use only for its stated simplified inputs and limitations.
Use Dew point calculator - 6
Optional
Estimate the purchase cost
Use the quantity from your chosen calculator and the supplier's package price.
Use Material purchase cost
Guidance for this job
How to calculate U-value from layers
Add homogeneous layer resistances, account for surface resistances and check the limits of a nominal U-value calculation.
Read guideDew point and condensation limitations
Air dew point is not an interstitial-condensation or mould assessment.
Read guide