How much does construction waste weigh per cubic metre?

It varies significantly by material type. Concrete rubble is the heaviest at approximately 2,200 kg/m³, followed by brick rubble at 1,800 kg/m³, soil at 1,500 kg/m³, mixed waste at 1,000 kg/m³, plasterboard at 800 kg/m³, and timber at 500 kg/m³. These are approximate densities for waste-form materials (not solid).

What is landfill tax and how much is it?

Landfill Tax is a UK government tax on waste sent to landfill, designed to encourage recycling and waste reduction. There are two rates: the standard rate of £102.10 per tonne for active (non-inert) waste like plasterboard, timber, plastic and mixed waste; and the lower rate of £3.25 per tonne for inert waste like brick, concrete, stone and uncontaminated soil. These rates are for 2024/25.

Why must plasterboard be separated from other waste?

Plasterboard (gypsum) must be separated because when it decomposes in landfill alongside biodegradable waste, it produces hydrogen sulphide gas which is toxic and has a strong rotten egg smell. Under the Environmental Permitting Regulations, plasterboard must be disposed of in a dedicated cell at landfill that does not contain biodegradable waste, or sent to a plasterboard recycling facility.

What waste is classified as inert for the lower landfill tax rate?

Inert waste attracts the lower landfill tax rate of £3.25 per tonne. This includes: brick, concrete, stone, tiles, ceramics, glass, uncontaminated soil and subsoil, rock, gravel, sand, clay, and calcium sulphate (when in a cell with only inert waste). These materials do not decompose, burn, or react chemically in landfill.

Can I reduce waste disposal costs?

Yes, several strategies can reduce costs: (1) Separate inert waste (brick, concrete, soil) from active waste to benefit from the lower landfill tax rate. (2) Recycle plasterboard through a dedicated service. (3) Use timber for biomass/fuel rather than landfill. (4) Crush brick and concrete on site for reuse as hardcore. (5) Use a waste transfer station rather than direct landfill for sorting. (6) Minimise waste through accurate ordering and careful handling.

Waste Tonnage Calculator — How Much Does My Construction Waste Weigh?

Calculate the weight of your construction waste by material type. Get skip size recommendations and landfill tax estimates for plasterboard, timber, brick, concrete, soil and mixed waste.

Enter volume for each waste type (leave at 0 if not applicable):

Plasterboard

~800 kg/m³ | Standard rate tax | Must be separated

Timber

~500 kg/m³ | Standard rate tax

Brick Rubble

~1800 kg/m³ | Lower rate tax

Concrete Rubble

~2200 kg/m³ | Lower rate tax

Soil / Earth

~1500 kg/m³ | Lower rate tax

Mixed Construction Waste

~1000 kg/m³ | Standard rate tax

How We Calculate This

This calculator converts waste volumes (in m³) to weight (in tonnes) using standard material densities, then estimates the landfill tax payable based on the waste type classification.

Material Densities (waste form)

Plasterboard: ~800 kg/m³ (standard rate tax)
Timber: ~500 kg/m³ (standard rate tax)
Brick rubble: ~1,800 kg/m³ (lower rate tax — inert)
Concrete rubble: ~2,200 kg/m³ (lower rate tax — inert)
Soil: ~1,500 kg/m³ (lower rate tax — inert)
Mixed waste: ~1,000 kg/m³ (standard rate tax)

Landfill Tax Rates (2024/25)

Standard rate: £102.10 per tonne (non-inert: plasterboard, timber, mixed, plastics)
Lower rate: £3.25 per tonne (inert: brick, concrete, soil, stone)

Plasterboard Separation

Plasterboard must be kept separate from other waste by law. It cannot be placed in a mixed skip. It must go to a dedicated plasterboard recycling facility or a specific landfill cell that contains no biodegradable waste.

Frequently Asked Questions

Related Calculators

Area Calculator

Calculate areas for rectangles, triangles, circles and irregular shapes.

Volume Calculator

Calculate volumes for cubes, cylinders, cones and irregular shapes.

Metres to Feet Converter

Convert between metric and imperial measurements.

Kg to Bags Converter

Convert bulk weights to bag quantities for common building materials.

Cubic Metres to Tonnes Converter

Convert volume to weight for aggregates, sand, soil and more.

Last updated: February 2026

All calculations are estimates. Verify with your supplier.