The room schedule inside a daylight report

A daylight and sunlight report is read through its room schedule. Officers and consultees rarely work through the modelling narrative first, and they almost never re-run the model. They open the appendix, find the table of rooms, and look for the rows that fail. So the daylight assessment room schedule is the part of the document that has to survive scrutiny on its own, without the author sitting next to it explaining what each column means.

Most of the disputes we see on flatted schemes are not disputes about physics. They are disputes about whether the row labelled "Flat 12, R2" is the bedroom shown on the consented drawing, whether it was assessed against the right target, and why one room in a block of 90 has no result at all.

What the schedule has to prove

Three things, in order. That every room capable of being assessed has been assessed. That each room was tested against the target appropriate to its use. And that the results reported in the table are the results that come out of the model, including the ones the applicant would rather not show.

A Daylight and Sunlight Assessment carries two families of numbers: internal daylight and sunlight for the proposed rooms, and the effect of the proposal on rooms in neighbouring buildings. Both belong in schedules, and they should be kept separate. Mixing proposed-scheme rooms with neighbouring rooms in one table is the fastest way to lose a reader.

BRE 209 (2022) now points to the illuminance approach in BS EN 17037 for new residential rooms. The UK national annex sets lower target illuminances than the European default, applied over half the reference plane area for at least half the daylight hours.

Where a council's policy still asks for average daylight factor, the older BRE targets of 1 per cent, 1.5 per cent and 2 per cent for bedrooms, living rooms and kitchens are what it means. Say which method you have used and why, in the schedule header, not buried in paragraph 4.3 of the main text.

Naming rooms so the schedule matches the drawings

Use the drawing's own reference. If the general arrangement plan calls a space "B1" on level 03, the schedule row says level 03, plot or flat number, B1. Inventing a parallel numbering system for the model is a habit worth breaking, because the reviewer then has to build a translation table before they can check anything.

Four fields do most of the work: level, unit reference, room reference, room use. A fifth field, the net internal room area, lets a reader sanity-check whether the reference plane was set up over the right space.

And be consistent about which unit label you follow. Sales numbering, plot numbering and the numbering on the fire strategy drawing are frequently different on the same scheme. Pick the one on the submitted plans.

Which rooms are assessed

Habitable rooms: bedrooms, living rooms, dining rooms, kitchens and combined living or dining spaces. Studies and home offices in a residential unit are normally treated as habitable where they are shown as such on the plan.

Rooms left out of the assessment, and the reason each is left out, should still appear somewhere. Bathrooms, en suites, WCs, utility cupboards, internal circulation, plant rooms and stores are excluded because there is no daylight requirement for them. A short exclusions note is better than a silent gap, because a gap looks like a room that failed and was deleted.

Two cases cause most of the argument. Rooms lit only by a rooflight over a deep plan, where the reference plane sits under a light well and the result depends heavily on the shaft geometry you modelled. And single-aspect kitchen-living-dining rooms, where the applicant applies the 150 lux living room target and the officer applies the 200 lux kitchen target. Say which you applied on the face of the table.

Grids, reference planes and the modelling assumptions behind each row

The reference plane for a dwelling sits 0.85 m above finished floor level, with the grid inset from the internal wall faces. Grid spacing of 0.5 m is typical for residential rooms, refined where the room is small. Every one of those choices changes the percentage of the plane that meets target, so each one belongs in a table of modelling parameters next to the schedule.

Record the assumptions that a reviewer cannot see in the geometry:

• window transmittance and glazing specification, including any solar control coating
• frame and mullion allowance as a percentage of the opening
• internal surface reflectances for walls, floor and ceiling
• external surface reflectance and the treatment of balconies, brise soleil and reveals
• the weather file or sky model used, and whether external obstruction was modelled from survey or from published mapping
• whether consented but unbuilt neighbouring schemes were included

Balcony soffits are the assumption most often left out, and on a deck-access block they can move a room from pass to fail on their own. Receptor definition is the same discipline that decides whether an acoustic report stands up, and the approach to identifying receptors in a noise impact assessment transfers directly: define the thing you are testing before you test it.

The columns a reviewer needs

A schedule that can be checked has, for each room: level, unit, room reference, room use, room area, the metric applied, the target value, the modelled result, the proportion of the plane meeting target, and a pass or shortfall flag. Sunlight rows add annual probable sunlight hours and the winter figure, for windows within 90 degrees of due south.

For neighbouring properties, the columns change. There the reader wants the existing value, the proposed value, the ratio of proposed to existing, and whether the BRE guideline of retaining at least 0.8 of the former value is met, alongside vertical sky component against the 27 per cent reference and the no sky line comparison.

Keep one row per room. Merged cells, colour-only pass indicators and footnote markers that point nowhere all make the table harder to audit. A text flag such as "below target" survives printing in greyscale.

Reporting shortfalls instead of burying them

Every dense urban scheme has rooms that fall short. The schedule is where you say so, and the main text is where you explain why the shortfall is acceptable in planning terms: aspect, depth, the balance struck against other policy aims, the standard of accommodation overall, the townscape reason the massing takes the form it does.

An illustrative example. On a six-storey infill block, three ground floor bedrooms sit behind a 1.8 m deep recessed balcony on the north elevation and reach roughly two thirds of the area meeting the 100 lux target rather than half or more. That is a shortfall in three rooms out of 54. Reported plainly, with the reason and the mitigation considered, it is a judgement for the officer. Omitted from the table and discovered by a consultee, it becomes a credibility problem across the whole document, and often a reason to ask for the assessment to be redone.

The same logic applies to a proposal's effect on neighbours. Where an Overshadowing Study shows amenity space dropping below the two hour sun-on-ground guideline over part of a garden, give the area and the hours, then argue the point.

Cross referencing to drawings and the rest of the application

The schedule should name the drawing numbers and revisions it was built from, and the date of the model. A report tested against revision C of the general arrangement plans, submitted alongside revision E, invites a validation query at best.

Where the scheme is Environmental Impact Assessment development, the daylight schedule usually sits as an appendix to a chapter, and the chapter has to summarise it accurately. The relationship between an appendix table and its chapter works the same way as the baseline chapter of an environmental statement relates to its technical annexes: the summary must not soften the data behind it.

Then keep the file. Section 73 variations, reserved matters and post-permission amendments all start with someone asking whether the daylight position has changed. That question takes an afternoon to answer if the schedule is clear about rooms, targets and assumptions, and a fortnight if it is not.

If you want a structured first draft of the surrounding narrative while your modeller works on the geometry, enter a postcode on PlanScope and see which reports the site is likely to need.

This is general guidance rather than legal advice. Check the position with your local planning authority or a qualified professional before relying on it. PlanScope provides AI-assisted draft reports for planning applications. Reports should be reviewed before submission. We do not guarantee planning approval.