If you’re planning a home extension, loft conversion, garage conversion or new build, you’ll almost certainly need architectural drawings. One of the biggest sources of confusion for homeowners is understanding which drawings are needed and when.
Planning drawings and Building Regulations drawings serve two completely different purposes. One helps you obtain permission to build, while the other explains how the building will actually be constructed.
This guide explains the differences, when each type of drawing is required, and why investing in the right drawings at the right stage can save time, money and costly delays.
What Are Planning Drawings?
Planning drawings are prepared to support a planning application or a Certificate of Lawful Development. Their purpose is to show the local planning authority:
- What you want to build.
- How it will look.
- How it fits within its surroundings.
- Its relationship to neighbouring properties.
Planning officers use these drawings to assess whether the proposal complies with local planning policies. They focus on the appearance and planning impact of the development—not how it will be built.
When Are Planning Drawings Required?
Planning drawings are commonly needed for:
- Householder planning applications.
- Lawful Development Certificates.
- Prior Approval applications.
- New‑build houses.
- Flat conversions.
- Commercial planning applications.
- Listed Building Consent.
- Conservation Area Consent where applicable.
Even where planning permission is not required, planning drawings are often needed to demonstrate that a proposal complies with Permitted Development Rights.
Our guide Do I Need Planning Permission? Your Complete Guide for England explains when planning permission is required.
What Do Planning Drawings Include?
A typical planning drawing package usually contains:
- Existing floor plans.
- Proposed floor plans.
- Existing elevations.
- Proposed elevations.
- Site location plan.
- Block plan.
- Existing and proposed roof plans where required.
Additional documents may also be required, including:
- Design and Access Statements.
- Heritage Statements.
- Planning Statements.
- Flood Risk Assessments.
- Tree reports.
The level of detail is sufficient for the planning authority to understand the proposal but is not detailed enough for construction.
What Are Building Regulations Drawings?
Once planning matters have been resolved, the project moves to the technical design stage. Building Regulations drawings provide the detailed construction information required by:
- Building Control.
- Builders.
- Structural engineers.
- Specialist subcontractors.
They demonstrate compliance with the Building Regulations, covering areas such as:
- Structure.
- Fire safety.
- Thermal insulation.
- Drainage.
- Ventilation.
- Accessibility.
- Moisture protection.
- Sound insulation where applicable.
These drawings become the blueprint used during construction.
When Are Building Regulations Drawings Required?
Most construction work requires Building Regulations approval, including:
- Home extensions.
- Loft conversions.
- Garage conversions.
- Structural alterations.
- Internal wall removals.
- New‑build houses.
- Roof replacements.
- Basement conversions.
Even projects carried out under Permitted Development Rights normally require Building Regulations approval.
What Do Building Regulations Drawings Include?
Building Regulations drawings are far more detailed than planning drawings. They typically include:
- Fully dimensioned floor plans.
- Construction sections.
- Wall, floor and roof build‑ups.
- Foundation details.
- Drainage layouts.
- Stair details.
- Fire safety information.
- Ventilation strategy.
- Insulation specifications.
- Structural coordination.
These drawings are usually accompanied by detailed written specifications and structural calculations where required.
Our guide What Should Building Regulations Drawings Include? A Complete Homeowner’s Guide explains the process step by step.
Planning Drawings vs Building Regulations Drawings
| Aspect | Planning Drawings | Building Regulations Drawings |
|---|---|---|
| Purpose | Demonstrate the design and appearance | Demonstrate technical compliance |
| Use | Used for planning applications | Used for Building Control approval |
| Focus | Focus on planning policy | Focus on construction standards |
| Detail | Show general layouts | Include full dimensions and construction details |
| Information | Limited technical information | Comprehensive technical information |
| Timing | Prepared before technical design | Prepared before construction begins |
In short:
- Planning drawings ask: Can you build it?
- Building Regulations drawings ask: How will it be built safely?
Do You Need Both?
In many cases, yes. A typical project follows this sequence:
- Prepare planning drawings.
- Obtain planning permission or confirm Permitted Development.
- Prepare Building Regulations drawings.
- Obtain Building Control approval.
- Begin construction.
However, not every project requires planning permission. Many extensions built under Permitted Development Rights still require detailed Building Regulations drawings before work begins.
Our guide Planning Permission vs Building Regulations: Do You Need One, the Other, or Both? explains the relationship between the two approval processes.
Why Good Drawings Save Money
Comprehensive drawings don’t just satisfy the authorities—they also benefit your project. Detailed drawings can:
- Reduce builder queries.
- Improve quotation accuracy.
- Minimise unexpected costs.
- Reduce construction delays.
- Avoid costly site changes.
- Improve coordination between trades.
Investing in good drawings at the outset is usually far less expensive than correcting mistakes during construction.
Common Homeowner Mistakes
- Assuming planning drawings are suitable for construction.
- Believing planning permission includes Building Regulations approval.
- Starting work before Building Control approval has been obtained.
- Relying solely on builder sketches rather than professionally prepared technical drawings.
Avoiding these mistakes can save significant time and expense.
How Draw & Plan Can Help
At Draw & Plan, we provide a complete architectural design service from initial feasibility through to construction.
Our Planning Drawings service includes feasibility advice, planning applications, Lawful Development Certificates and Prior Approval submissions, helping homeowners secure the necessary planning consents.
Once planning matters have been resolved, our Building Regulations Drawings provide the detailed technical information required for Building Control approval and construction, working closely with structural engineers where required.
For independent guidance, the Government’s Building Regulations approval page and the Planning Portal guide to Building Regulations explain the approval process, while the Planning Portal’s guide to Planning Permission provides useful information on planning applications.
Ready to discuss your project? Contact us today for a free, no‑obligation quotation.
Further Reading
Disclaimer: This article is for general informational purposes only and does not constitute legal or professional advice. Planning permission and Building Regulations requirements vary depending on the nature and location of each project. Always seek advice from suitably qualified professionals and your local planning authority or Building Control body before commencing work.