Getting lighting right is mostly arithmetic. Diameter comes from room size, pendant spacing comes from island length, sconce height comes from eye level, and fan sweep comes from square footage.
The guides below walk through one decision each — the measurements designers actually use, the exceptions worth knowing, and the fixtures that fit.
On this pageChandelier sizing · Kitchen island lighting · Bathroom vanity lighting · Ceiling fan sizing · Talk to a designer
Quick answers
| Question | Short answer | Full guide |
|---|---|---|
| What size chandelier do I need? | Add the room's length and width in feet — that number, in inches, is your diameter. Over a table, use half to two-thirds the table width. | Chandelier sizing |
| How high should a chandelier hang? | 30″–36″ above a dining table on an 8′ ceiling. Everywhere else, keep 7′ of floor clearance. | Chandelier sizing |
| How many pendants over a kitchen island? | Two for a 4–5′ island, three for 6–7′, three large or one linear fixture for 8–10′. | Island lighting |
| How far apart should island pendants be? | 24″–30″ between centers, at least 6″ clear at each end, 30″–36″ above the counter. | Island lighting |
| How high do vanity sconces go? | Centers at 60″–66″ from the floor, 36″–40″ apart. A bath bar above the mirror goes at 75″–80″. | Vanity lighting |
| What size ceiling fan for my room? | 42″–48″ for a room up to 12′ × 12′; 52″–56″ for most primary bedrooms and family rooms. | Ceiling fan sizing |
| What downrod length do I need? | 12″ for a 10′ ceiling, 18″ for 11′, 24″ for 12′ — the goal is blades 8–9′ above the floor. | Ceiling fan sizing |
How to Size a Chandelier
The formulas for diameter and hanging height in every room a chandelier belongs in — dining rooms, living rooms, bedrooms, single-story entries, and two-story foyers. Includes what changes when the table is round, when the ceiling is tall, and when an open-frame design lets you size up.
- Room-size and table-width diameter formulas
- Hanging heights for 8′ ceilings and up
- Two-story foyer proportions
- Sizing linear chandeliers to long tables
Read the chandelier sizing guide for more information →Or shop chandeliers and semi-flush lights.
Kitchen Island Lighting
Island pendants hang at eye level in the room everyone gathers in, which makes them the easiest fixtures in the house to get wrong. This one works through the count, the spacing math, the mounting height, and how to match light output to the way you actually use the island.
- Pendant count by island length
- Center-to-center spacing, worked through on a 72″ island
- Mounting height and lumens per square foot
- Dimmer compatibility for integrated LED pendants
Read the kitchen island lighting guide for more information →Or shop pendant lights and kitchen island lighting.
Bathroom Vanity Lighting
Most bathrooms are lit by a single overhead fixture that throws shadows exactly where you don't want them. This guide covers the placement that fixes it, how to size a fixture to the vanity, and the light-quality specs — color temperature, lumens, CRI, damp rating — that decide how the room actually feels.
- Sconce heights and spacing, and when a bath bar is the better call
- Fixture width by vanity size, from 24″ singles to 72″ doubles
- Color temperature, lumens and CRI for flattering light
- Damp ratings and mixing finishes
Read the bathroom vanity lighting guide for more information →Or shop vanity lights and wall sconces.
How to Size a Ceiling Fan
Three decisions get a fan right: blade sweep for the room, downrod length for the ceiling, and the direction it should spin in each season. Includes the full downrod chart from 8′ ceilings to 18′ and up, and which rating a covered porch needs.
- Blade sweep by room square footage
- Downrod length chart by ceiling height
- Indoor, damp and wet ratings
- Summer and winter blade direction
Read the ceiling fan sizing guide for more information →Or shop ceiling fans, outdoor fans, and downrods and accessories.
Let a designer size it for you
Send us the room — dimensions, ceiling height, and a photo if you have one — and a certified designer will spec the fixture and the size with you on a 15-minute call. Phone or video, no charge, no obligation.
Book a 15-minute consultation →New to this? See how a design consultation works, or meet the designers.