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Bigelow Interior Design

The Design Studio

The Paint & Light Harmony Studio

The same white reads warm in one room and cold grey in the next. Tell us which way your room faces and what you are considering — we will tell you how it will really look.

Why your paint never looks like the sample

It is almost never the paint's fault, and almost always the window's. Once you know which way a room faces, most colour disasters become entirely predictable.

01

The chip is lying to you.

A colour card is viewed under shop lighting, at two inches square, against white paper. On four walls, under your own window, it becomes a different colour entirely. That gap is not bad luck — it is predictable physics, and it is what this tool models.

02

Your window has a colour.

North light is blue. South light is golden. East and west swing across the day. Paint does not sit apart from that cast — it either compounds it or balances it. Choose a cool grey for a north room and you compound the blue, which is why it turns violet.

03

LRV is the number nobody reads.

It is printed on almost every colour card and it tells you more than the name ever will. Two colours that look identical on paper can behave completely differently on a wall if their reflectance values are twenty points apart.

The Design Studio

The Paint & Light Harmony Studio

The same white looks warm in one room and grey in the next. Tell us which way your room faces and we will tell you how your colour will actually behave on the wall.

Which way does the room face?Northern Hemisphere — swap north and south if you are below the equator.
What are you going for?Open, reflective, full of light.
Paint undertone family
Light Reflectance Value55
Printed on the back of most paint cards. 1 is black, 100 is pure white.

Target for this room and look: LRV 65–80

Likely to disappointCool Gray · LRV 55 · North-facing

How this paint will actually behave in your room

Your light is cool, blue-toned and indirect. It never gets direct sun, so the light stays even all day but drains warmth out of everything it touches.

This is the pairing that goes wrong most often. North light is already blue, and a cool grey has nothing warm in it to push back — so the two compound. On the wall it will read dingy, and in the corners and shadows it will turn distinctly violet or purple. It will not look like the swatch, and no amount of lighting fully rescues it.

LRV 55 sits just under the 65–80 band for this look. Expect the room to feel a shade more enclosed than you intend — fine if you like that, worth nudging up if you do not.

Safer choices for a north-facing room

Chalky plaster

LRV 73

Matte and slightly pink-beige. Holds its warmth even in weak light.

Creamy oat

LRV 74

Openly warm. The safest choice for a room that never sees sun.

Pale putty

LRV 68

Quietly warm and forgiving under changeable light.

Whatever you choose, buy a sample pot and paint a large sheet of card — not the wall itself. Move it to each wall and look at it in the morning, at midday and at night before you commit. Every colour lies on a small chip.

LRV measures how much light a colour reflects, from 1 (absorbs almost everything) to 100 (reflects almost everything). Most manufacturers print it on the back of the card or list it online.

Common paint questions

What is LRV in paint?
LRV stands for Light Reflectance Value, a scale from 1 to 100 measuring how much light a colour reflects. A value of 1 is close to pure black and absorbs almost all light; 100 is close to pure white and reflects almost all of it. Most manufacturers print the LRV on the back of the colour card. As a rough guide, anything above 65 reads light and airy, 45 to 65 reads mid-tone, and below 30 reads genuinely dark.
What LRV is best for a north-facing room?
Choose an LRV above 60 with a warm undertone. North-facing rooms never receive direct sun, so the light arriving is cool and blue, and it drains warmth from everything it touches. A higher LRV compensates for the lower light level, while the warm undertone counteracts the blue cast. For a bright, airy result, aim for LRV 65 to 80.
Why does grey paint look purple or blue in my room?
Because the room almost certainly faces north. Cool grey has a blue or violet undertone, and north light is itself blue, so the two compound instead of cancelling out. The result reads dingy across the main wall and turns visibly violet in corners and shadows. The fix is not a different grey but a warmer one — a greige or warm neutral gives the light something to work against.
What paint colours work in a south-facing room?
Muted, slightly cooler shades with a mid-range LRV, roughly 55 to 72. South-facing rooms get intense warm sun for most of the day, which washes pale colours out to plain white and amplifies any yellow already in the paint. Greige and soft grey behave particularly well here, because the warm light neutralises their coolness rather than leaving them bleak.
Can a paint colour be too bright or reflective?
Yes. In a south or west-facing room, an LRV above about 78 will glare in direct sun, becoming uncomfortable to sit opposite and bleaching the colour out entirely. This is why brilliant whites often disappoint in sunny rooms: there is nothing left to see. Dropping ten to twenty LRV points lets the wall absorb some of that intensity and hold onto its character.
How does light change paint colour through the day?
East and west-facing rooms shift the most. An east-facing room is warm and golden in the morning, then flat and cool from midday onward. A west-facing room is cool through the morning and intensely warm and orange by late afternoon. North light stays consistently cool all day, and south light stays warm. Always judge a sample at the time of day you actually use the room.
Should you test paint samples on the wall?
Paint a large sheet of card instead, then move it around the room. Testing directly on the wall traps you: the existing colour underneath skews what you see, and patches influence each other. A separate board can be held against each wall, viewed in morning, midday and evening light, and propped beside your flooring and furniture — which is where most colour decisions are actually won or lost.

Planning the lighting too? Colour and light are the same decision — visit the Room Ambience Planner.