Building Regulations Drawings vs Planning Drawings: What Is the Difference?

One of the most common sources of confusion for homeowners embarking on a construction project is the difference between planning drawings and building regulations drawings. Both are required for most significant works, but they serve entirely different purposes and contain different information.

Planning drawings are used to obtain planning permission from the local planning authority. They show the proposed design of the building from the outside — elevations, floor plans showing layout, a site plan showing the building in context, and often existing and proposed drawings in parallel. The purpose of planning drawings is to allow the local authority to assess whether the proposed development is acceptable in planning terms: whether it is the right size, in the right position, has an acceptable impact on neighbours and the streetscene, and complies with planning policies.

Planning drawings are typically produced by an architect or designer and do not need to show construction details, material specifications, structural design, drainage routes, insulation specifications, or fire separation. They need to show what the building will look like, where it sits on the plot, and how it relates to neighbouring buildings and the street.

Building regulations drawings (also called technical drawings, construction drawings, or working drawings) serve a completely different purpose. They are used to demonstrate to Building Control that the proposed works will comply with the Building Regulations — the technical standards for structural safety, fire resistance, energy efficiency, ventilation, drainage, and accessibility that apply to construction in England.

Building regulations drawings contain far more technical detail than planning drawings. They typically include: structural details (beam sizes, foundation depths, connection details), insulation specifications and U-value calculations, ventilation and MVHR layouts, drainage and rainwater disposal details, fire separation and intumescent products, staircase and balustrade dimensions, means of escape in case of fire, and often details of materials and products to be used.

A key practical point is that planning drawings, even if approved, cannot be used to build from. They lack the technical specification a builder needs to construct to the correct standard. Building regulations drawings are what the contractor uses on site, and they are what Building Control inspects against.

For most projects, you will need both: planning drawings first (to get planning permission), then building regulations drawings (to get Building Regulations approval and provide the construction specification). On simpler projects within Permitted Development, planning drawings may not be needed at all — only building regulations drawings.

RCB works with architects and structural engineers to coordinate both sets of drawings as part of the pre-construction process, ensuring that what is designed and approved can actually be built. +44 7359 872594 | connect@rcbGroup.co.uk | www.rcbGroup.co.uk