Daylight Reports for Homeowners Building an Extension

Planning a rear, side, wraparound or two-storey extension? We check how it affects your neighbours' daylight and sunlight and give the planners the clear evidence they need.

Glazed rear extension on a London terraced house at dusk

Your home, your extension

Don’t let an objection stand in the way of your extension.

You’ve worked hard for your home, and you have every right to improve it. A well-designed extension can transform how you live, and it shouldn’t be held back by worries that aren’t backed up by the facts.

When a neighbour objects on daylight or sunlight grounds, the concern is often bigger than the real impact. Our report measures what actually changes, using the BRE guidelines planners rely on, so your application is judged on evidence rather than assumptions.

Objections today often come packed with familiar phrases like “overbearing”, “loss of light” and “harm to amenity”, many of them written with AI. The good news is that real measurements usually tell a much calmer story. If one comes in, we answer it point by point with hard numbers, giving the planning officer the confidence to support your extension.

REPORTS WE PROVIDE

The reports your council may ask for when you extend your home.

Neighbour Impact Reports

BRE 209 assessments including VSC, NSL, APSH and SOG.

Neighbour Solar Panel Impact Reports

APSH impact assessments for proposed solar panel installations nearby.

WHY HOMEOWNERS CHOOSE US

Clear advice for your extension.

— Over 400 reports completed across the UK

— Fast turnaround, typically 4-5 working days

— Fixed fee agreed before you commit

— Plain-English advice, no jargon

— Help if a neighbour objects to your extension
Kitchen in a glazed side-return extension overlooking a garden
Open-plan living space in a rear extension with glass roof and garden doors
OUR TECHNICAL PROCESS

A proven process that delivers.

01  Receive Plans — CAD, PDF and 3D models.

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02  3D Modelling — accurate SketchUp models.

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03  Specialist Analysis — BRE-approved software.

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04  Quality Review — checked by our senior team.

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05  Defensible Report — clear, planning-ready.

BENEFITS FOR HOMEOWNERS

Peace of mind for your extension.

Avoid planning objections

Respond to objections

Avoid planning delays

How much will my extension report cost?

£499 + VAT covers the simplest job: a terraced house under 100 m² with a single-storey rear extension affecting one neighbour. Most home extension reports are £675–£935 + VAT. Every fee is fixed and agreed before you commit.

Frequently asked
questions

Everything you need to know before ordering a report.

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Still need help?

Please reach us at info@sunlightassessments.co.uk
if you cannot find an answer to your question.

What happens if the assessment does not meet the BRE guidelines?

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Not meeting a BRE guideline does not automatically mean planning permission will be refused. We review the results in context and, where possible, recommend design changes or provide supporting commentary to help strengthen the planning case.

How much does a daylight and sunlight assessment cost for a home extension?

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£499 + VAT covers the simplest job: a terraced house under 100 m² with a single-storey rear extension affecting one neighbour. Most home extension reports are £675–£935 + VAT.

What moves the fee up is how many neighbouring properties need testing, a larger house or a semi or detached rather than a terrace, and a two-storey, wraparound or roof extension rather than a single-storey rear. Whatever your project, the fee is fixed and agreed in writing before you commit.

Use the instant calculator for a quick estimate, or send us your plans for a confirmed fixed-fee quote.

What is the 45 degree rule?

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The 45-degree rule is a planning rule of thumb used to assess whether a proposed extension or development could affect the daylight and sunlight received by neighbouring properties. If a proposal extends beyond a 45-degree line from a neighbouring window, a more detailed daylight and sunlight assessment may be recommended. It does not automatically mean the proposal will be refused.

Worried a neighbour might object?

Send us your extension plans and we'll tell you what the planners are likely to look for, with a fixed fee before you commit.