What is a demolition method statement?

A demolition method statement is a detailed document required under CDM 2015 (Construction Design and Management Regulations) that describes how the demolition will be carried out safely. It covers the sequence of operations, temporary support arrangements, exclusion zones, plant and equipment, waste management, and emergency procedures. A structural engineer must review the method statement for any structural demolition.

Why must demolition proceed from the top down?

Top-down demolition is the standard approach because it maintains the stability of the remaining structure at all times. The roof and upper floors are removed first, progressively reducing the load on the structure below. This prevents uncontrolled collapse. The only exception is controlled explosive demolition, which requires specialist planning and licensing.

When is a debris chute needed?

A debris chute is required for buildings over 2 storeys (approximately 6m) to safely transfer demolition waste to skips at ground level. Chutes prevent the hazard of throwing or dropping materials from height. They must comply with the Work at Height Regulations 2005 and are typically constructed from interlocking sections of heavy-duty plastic or steel.

What temporary support is needed during structural demolition?

Temporary support (shoring, propping, or bracing) is required wherever the demolition sequence creates unsupported elements. This includes floor slabs after supporting walls are removed, freestanding walls that lose lateral support, and any structure that becomes unstable during the demolition sequence. A structural engineer must design the temporary works.

Do I need planning permission for demolition?

In England, demolition of a building over 50m³ requires prior notification to the local authority under Section 80 of the Building Act 1984. Planning permission is not usually required for demolition alone, but is needed if the site is in a Conservation Area (where demolition needs Conservation Area Consent), if the building is Listed, or if there are specific planning conditions.

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Structural Demolition Calculator

Calculate load transfer identification, temporary support positions, demolition sequence planning, and debris chute requirements for structural demolition projects.

Structure TypePrimary structural system

Footprint Area

Ground floor footprint area

Number of Floors

Total floors including ground

Total Height

Overall building height

Demolition MethodAffects productivity and duration

Load-Bearing Walls

Number of load-bearing walls per floor

How We Calculate This

This calculator helps plan structural demolition by estimating debris quantities, identifying load transfer points, determining temporary support needs, and generating a demolition sequence per BS 6187:2011 (Code of Practice for Demolition).

Debris estimation

Total building volume × fill factor (proportion of volume that is solid material) × material density gives the debris weight. Fill factors range from 0.15 for steel frame to 0.35 for solid masonry construction.

Load transfer analysis

Load transfer points are identified at each load-bearing wall × each floor level. Temporary support must be provided wherever demolition creates unsupported loads. The number of temporary supports is typically 50% of load transfer points, as some elements can be demolished in sequence.

Demolition sequence

The sequence follows BS 6187 principles: soft strip first, hazardous materials next, then top-down structural demolition from roof level to foundations.