Insulation calculator
Insulation volume, number of slabs and packs from area and thickness.
Fill in the fields and the result will appear here automatically.
Calculates volume for one insulation layer and whole slabs and packs from your dimensions. Thickness refers to the purchased slab or chosen layer; slab count covers the area once. This is a quantity calculation, not a thermal-performance, moisture or assembly design.
How it works
Formula and logic
V = A·t/1000 with t in mm. Slabs = ⌈A/a⌉; packs = ⌈slabs/k⌉, where a is one slab area in m² and k is a positive integer slabs per pack. A, t and a are positive and finite. Purchase counts round upward using decimal dimension values without deleting a real small remainder; enter any area allowance yourself.
Example
60 m² at a 100 mm layer is 6 m³ of insulation: 84 slabs of 0.72 m², which is 14 packs of six.
Fields and units
- Area to insulate — m²
- Layer thickness — mm
- Area of one slab — m²
- Slabs per pack — unitless
How to use
- — Enter area and thickness for one layer.
- — Specify one purchased slab area in m² and whole slabs per pack.
- — Calculate multiple layers separately and add quantities.
Method and limitations
- Calculation method
- Formula and logic
- Limitation
- This is a quantity calculation, not a thermal-performance, moisture or assembly design.
FAQ
Why does the slab count round up?
This model purchases whole slabs. Any positive remainder needs another slab; it does not plan cutting or reuse of offcuts.
Where do slab area and pack count come from?
Use the actual product label. The 0.72 m² example corresponds to 1200×600 mm; pack contents are a separate input.
How do I include a cutting allowance?
Increase the entered area by the allowance from your layout. No fixed percentage or separate allowance field is provided.
Can I calculate two layers?
Calculate each layer with its own thickness and format, then add quantities. Combined thickness over the same area gives total volume but leaves slab count at one layer.