Interior Natural Light Observation Record Checklist

Decide which rooms you will observe and record each one separately, since a note about the property as a whole says nothing useful about any single room.

Daylight behaviour differs so sharply between rooms that combined notes cancel each other out.

Take photographs from the same position each time, standing or sitting where you actually spend time rather than in the doorway.

Doorway photographs flatter every room, and nobody experiences the space from there.

Note the time of day and the weather in plain words alongside each observation, because bright overcast and direct sun behave completely differently indoors.

Without the conditions written down, two photographs of the same room become impossible to compare.

Make observations on more than one kind of day, including a thoroughly dull one, so the record is not built entirely from good weather.

A room is usually judged in bright weather and then lived in through a great deal of dull weather, which is the harder test.

Record whether an observation was made with blinds and curtains as they normally sit, rather than pulled fully back for the photograph.

A record of a room that never exists in daily life leads to decisions that do not survive contact with it.

Write down what you notice in words as well as taking photographs, since a camera evens out contrasts that your eye finds obvious.

Phone cameras brighten dark corners automatically, which quietly deletes the thing you were trying to record.

Work out which wall each window sits in and roughly which direction it faces, using a compass on a phone rather than relying on your sense of it.

Owners are wrong about orientation more often than they expect, and every later observation depends on getting it right.

Record whether a room is lit through openings on one side only, since a single-aspect room behaves quite differently from one lit from two directions.

Light from a single side falls away sharply across a room, and no finish choice fully compensates for that.

List anything between the glass and the room, such as a deep reveal, a blind housing, a run of shelving or a plant on the sill.

The obstruction closest to the opening removes more light than anything further into the room.

Record where an internal door or glazed panel passes light between rooms, and note what happens to the far room when it is closed.

A room lit through a doorway loses most of its light the moment somebody wants privacy.

Identify any room that borrows all its daylight from somewhere else, and say exactly where that light comes from.

These rooms are the ones where an artificial lighting conversation matters most, and they are easy to describe wrongly.

Write down which openings you never open and which you never uncover, so the record describes the room as it is actually lived in.

A permanently covered opening is doing less than the plan suggests, and the reason is usually worth stating.

Record what stands outside each window — a wall, a fence, planting, a neighbouring building — and how close it is in rough terms.

A close boundary changes the character of the light as well as the amount of it, and it is rarely mentioned in a brief.

Check whether anything shading a window loses its leaves, since a window shaded by foliage in one season is not shaded in another.

Owners often observe a room in one season and choose finishes for a room that behaves differently in the next.

Record whether a light-coloured wall or paving outside is bouncing light into the room, since changing that surface would change the room.

Reflected light from outside is easy to miss and easy to lose without anybody connecting the two.

Trace where a structure outside casts a shadow that moves across the room, and roughly where that shadow lands at each observation.

A moving shadow explains why a room feels different at different times far better than any general impression.

Write down anything outside that is likely to change, such as planting that is still growing or building work nearby.

Decisions made for the current outlook can be undone by something entirely outside your control.

What may be built or altered near your property is a matter to confirm locally with the relevant authority rather than to assume from what you can see.

Be honest about whether a window looks onto something you avoid looking at, because that affects whether the daylight there is actually welcome.

Rooms get permanently screened for outlook reasons, and the light lost is then blamed on the building.

Follow the brightest patch of light through a room from morning to evening and mark roughly where it falls at each of your observations.

This produces one of the most useful drawings an owner can make, and it takes nothing but attention.

Note what the bright patch lands on — a floor, a seat, a work surface, a screen — because that is what will warm, dazzle or fade.

Where direct sun lands regularly is where finish choices need the most care.

How a particular material or textile responds to direct sun is a question for the supplier or maker, not something to judge from a sample indoors.

Record where you find yourself moving to as the light changes, since that is the room telling you something you have not put into words.

Habitual movement is more reliable evidence than opinion about which parts of a room work.

Pin down the point in the day at which each room stops being usable without switching a light on.

This single observation tells a lighting conversation more than a description of how bright the room feels.

Record which rooms are used mainly after dark, because daylight matters far less there than whatever replaces it.

Finishes for a room used mainly at night should be judged at night, and almost never are.

Compare an observation made in one season with one made in another before treating the record as finished.

The path of direct light shifts enough between seasons to change which parts of a room are usable.

Mark the corners that stay dull whatever the weather, and note what currently happens in each of them.

A dark corner used for reading is a problem; a dark corner holding a bookcase may not be one at all.

Consider whether a dark corner is dark because of the opening, the depth of the room, or something standing in the way of the light.

Only one of those three causes is likely to be within reach of an interior decision.

Record what colour and finish the surfaces already are in the darkest part of each room, since dark finishes there compound what daylight cannot reach.

The same colour reads quite differently at the two ends of a single-aspect room.

Find where somebody regularly does something needing good light in a spot that has none, such as reading, sewing or preparing food.

These mismatches persist for a very long time because the furniture arrived before anybody thought about the light.

Record where a light is switched on during daylight hours, and which light it is, since that is the clearest evidence of a daylight shortfall.

Owners describe rooms as light or dark inaccurately, but switching behaviour does not lie.

Ask a qualified professional what might be done about a persistently dark space rather than assuming a larger opening is the answer.

The options are wider than most owners expect, and several of them do not involve altering the building at all.

Adding or enlarging an opening is not an interior decision, so put it to a qualified professional and confirm locally what would apply.

Note where sunlight strikes a screen or a working surface and makes it unusable, and at which point in the day that happens.

It is a frequent reason a desk or a seat ends up somewhere nobody would otherwise have chosen.

Record which mirrors and glossy surfaces already throw light around the room, and note where the reflection lands.

A reflection that is pleasant in one seat is often directly in the eyes of somebody in another.

Watch where you squint, shade your eyes or turn a chair away, since those reactions locate glare more reliably than any description.

People adapt to glare unconsciously and then forget it was ever a problem worth mentioning.

Record where light reflects off the floor finish, and how that changes when the floor is wet or has just been cleaned.

A finish sampled dry and matt in a showroom can behave very differently across a sunlit floor.

Note where an existing blind or curtain is being used for glare rather than for privacy, because those two jobs lead to different answers.

A treatment chosen for privacy often fails at glare, and the household simply stops using the room at that time.

Ask what a lighting or window treatment supplier needs to know about glare in a room before they propose anything for it.

Sending observations they can use is far more productive than describing the room as bright or dark.

Proposals for shading or lighting belong with suitably qualified suppliers and professionals, who should be given your observations rather than your conclusions.

Look at any sample in the room it is intended for, at more than one point in the day, before forming a view about its colour.

Colour shifts with the light reaching it, and a single viewing tells you about that moment only.

Note that a finish chosen under showroom light frequently reads differently at home, and record how each sample behaves in your own room.

Showroom lighting is chosen to present materials well, which is a different job from representing them accurately.

Ask the supplier what they can confirm about colour, sheen and batch variation, since a sample viewed in a room cannot settle any of that.

Record which rooms are used mainly under artificial light and judge samples there under that light as well as by day.

A finish that only works by daylight will be seen at its worst for most of the hours it is actually used.

Flag where two rooms with different daylight are to be given the same finish, and check the sample in both before deciding.

The same colour across two aspects can look like two different decisions once it is on the wall.

Record how a sample looks against the existing floor and against the light from the window, rather than on a table in the middle of the room.

Samples are almost always judged against a surface that will not be there afterwards.

Keep the light observations with the samples themselves, so the two are read together rather than remembered separately.

Sample decisions are revisited later, and by then nobody remembers under what light the first judgement was made.