The Value of Natural Light in Commercial-to-Residential Conversions

Natural light is one of the most important factors in determining whether a commercial building can successfully be converted to residential use. It influences not only planning success, but also the market appeal, sustainability performance, and long-term comfort of the finished homes.

The Town and Country Planning (General Permitted Development) (England) Order 2015 (as amended) (“GPDO”) provides powerful rights to convert certain use classes to residential, all of which require "the provision of adequate natural light in all habitable rooms of the dwellinghouses".

At the earliest feasibility stage, understanding how daylight reaches a building helps to shape layouts, window design, and overall viability.

Many commercial buildings have deep floorplates or limited glazing that make achieving good daylight a challenge — but with the right early design advice, potential issues can be addressed before they affect cost or design.

Beyond meeting planning policy, daylight is also central to sustainable building design.

It contributes directly to recognised standards such as BREEAM Hea 01 (Visual Comfort) and helps to reduce energy demand by minimising reliance on artificial lighting.

Well-daylit spaces also support resident wellbeing, productivity, and overall satisfaction — key qualities that drive sales value and rental performance.

However, good daylight design isn’t simply about maximising light. It’s about balance.

Too much unfiltered sunlight can cause glare and overheating, particularly in highly glazed or south-facing façades. By integrating passive design measures such as shading, solar control glazing, and smart façade strategies, developers can achieve bright, comfortable, and energy-efficient living environments.

In short, natural illumination is not just a design consideration — it’s a strategic advantage to help maximise asset value.

Early daylight and sunlight assessments can unlock the true potential of a site, helping to secure planning consent, enhance sustainability credentials, and deliver homes people truly want to live in.