Lighting Size & Installation Guide
Choosing the right fixture is as much about proportion as it is about light. This guide walks you through the sizing formulas interior designers use, ceiling-height rules, room-by-room recommendations, and safe installation practice — so every room in the house gets the light it deserves.
SizingHow to size a light fixture
Three formulas cover almost every fixture decision. Apply them in order: diameter first, then fixture height, then hanging height. They work for chandeliers, pendants and flush ceiling lights alike.
Example: a 3.5 × 4.5 m living room → 3.5 + 4.5 = 8 → a fixture around 65 cm in diameter sits in proportion.
Example: a 3 m ceiling → 65–75 cm of fixture height. Too short looks stubby; too tall overwhelms the room.
Applies to dining tables, kitchen islands and worktops: low enough to light the surface, high enough to see across it.
Multiple pendants over one surface
When hanging two or more pendants over a long table or island, size each pendant at roughly one quarter of the length of the surface below it. Space them evenly, keep at least 15 cm of clearance at each end, and aim for 60–75 cm between pendants, measured centre to centre.
CeilingsCeiling height guide
Ceiling height shapes every fixture decision — from the type of fixture to the length of the cord.
| Ceiling height | Fixture type | Min. floor clearance | Notes |
|---|---|---|---|
| 2.4 m (low) | Flush / semi-flush ceiling light | 2.1 m | Keep cords short; avoid long-drop pendants |
| 2.7–3 m (standard) | Pendant / chandelier | 2.1 m | The sweet spot — most fixtures are designed for this range |
| 3–3.7 m | Larger chandeliers | 2.3 m | Extend the cord; choose taller shades |
| 3.7 m + | Oversized or cluster | 2.4 m | Multi-light clusters and grand chandeliers draw the eye upward |
| Vaulted / sloped | Check the canopy | 2.1 m min. | Confirm sloped-ceiling compatibility on the product page, or ask our support team |
Living room
Usually the largest and most complex space to light. It benefits from layered light: ambient overhead, task lamps beside seating, and accent light working together. Keep at least 2.1 m of clearance under the fixture.
| Room size | Recommended diameter | Floor clearance |
|---|---|---|
| Under 14 m² | 35–55 cm | Min. 2.1 m |
| 14–23 m² | 55–70 cm | Min. 2.1 m |
| 23–37 m² | 70–90 cm | Min. 2.3 m |
| 37 m² + / open plan | 90–120 cm or a cluster | Min. 2.4 m |
Dining room
The dining fixture is the room's focal point. Rule: fixture diameter = ½ to ⅔ of the table width, hung 80–90 cm above the table surface. For tables over 180 cm, two or three smaller pendants spaced evenly create a calmer rhythm than one oversized fixture.
| Table size | Single fixture | Two fixtures (each) |
|---|---|---|
| 90 cm round / 4 seats | 40–55 cm | 25–35 cm |
| 120–150 cm rectangular / 6 seats | 55–70 cm | 35–45 cm |
| 180–215 cm rectangular / 8 seats | 70–90 cm or two fixtures | 45–60 cm |
| 245 cm + farmhouse table | Use 2–3 pendants | 50–70 cm |
Kitchen
Task efficiency first, aesthetics second. Rule: each pendant ≈ ¼ of the island length, hung 80–90 cm above the worktop, spaced 60–75 cm apart centre to centre. Supplement with recessed and under-cabinet lighting.
| Island length | Pendants | Diameter each | Hang height |
|---|---|---|---|
| Under 120 cm | 1 | 25–40 cm | 70–85 cm above worktop |
| 120–180 cm | 2 | 25–35 cm | 70–85 cm |
| 180–245 cm | 2–3 | 25–40 cm | 70–90 cm |
| 245 cm + | 3, or 1 linear | 30–45 cm / 120–180 cm linear | 75–90 cm |
Bedroom
Warm, layered light: a central ceiling fixture for ambient coverage, with bedside lamps or pendants for reading. Hang bedside pendants so the shade centre sits at eye level when seated in bed — typically 120–150 cm from the floor.
| Use case | Fixture diameter | Height / placement |
|---|---|---|
| Central ceiling fixture | Room formula above | Min. 2.1 m from the floor |
| Bedside hanging pendant | 20–35 cm | 120–150 cm from the floor |
| Above-bed decorative pendant | 40–60 cm | 180–215 cm from the floor |
| Bedside table lamp | See bedside sizing below | Eye level when seated |
Bathroom
Eliminate shadows, especially at the mirror — side-mounted wall lights flatter the face far more than a single overhead bar. Rule: mount wall lights 165–175 cm from the floor, flanking the mirror.
| Fixture type | Placement | Notes |
|---|---|---|
| Mirror wall lights | 165–175 cm from floor, either side of the mirror | The most flattering facial light |
| Overhead mirror bar | Directly above the top of the mirror | For smaller bathrooms without space beside the mirror |
| Ceiling flush mount | Centred; room formula | Ambient layer — combine with mirror lighting |
| Shower / wet zone | Appropriately IP-rated fittings only | Bathroom zones have specific IP requirements — check before you buy |
Hallway & entrance
The entrance fixture sets the tone for the whole house — going bold rarely looks wrong. Keep a minimum of 2.1 m clearance under the fixture. In hallways, space flush ceiling lights every 2.5–3 m; wall lights in between add warmth.
| Ceiling height | Fixture diameter | Drop / cord length |
|---|---|---|
| 2.4–2.7 m | 30–50 cm | Short — 45–60 cm |
| 3–3.7 m | 45–70 cm | Medium — 75–105 cm |
| Double height 4 m + | 60–100 cm | Long — 120 cm + |
Home office
Eliminate glare on screens while keeping enough ambient light to prevent eye strain — never rely on the ceiling fixture alone. Pair a diffuse ceiling fixture with a desk lamp on your non-writing side; aim any directional light at walls or work surfaces, away from screens.
LampsBedside lamp sizing
A bedside lamp that is too tall throws light in your eyes; too short and the shade hides behind the pillows.
| Lamp part | Ideal measurement |
|---|---|
| Total height | Bedside table height + 5–8 cm |
| Shade height | ½ to ⅔ of the total lamp height |
| Shade width (widest point) | Twice the width of the base |
| Base height | ⅓ of the total lamp height |
| Base width (widest point) | ½ of the shade width |
Bulb colour temperature
| Room | Temperature | Character |
|---|---|---|
| Living room, bedroom, dining room | 2700K–3000K (warm white) | Relaxed, welcoming — the residential standard |
| Kitchen, home office | 3000K–3500K (neutral white) | Better task visibility without feeling clinical |
| Avoid in living spaces | 5000K + (daylight) | Cold and clinical — works against most interiors |
For maximum flexibility, choose dimmable LED bulbs — many of our fixtures offer warm, neutral and cool settings, or stepless dimming with a remote.
InstallationInstallation & safety
Hardwired fixtures
Chandeliers, pendants, ceiling lights and wall lights that connect directly to your home's mains supply should be installed by a qualified electrician. In the UK, fixed electrical work must comply with BS 7671 wiring regulations (and, in England and Wales, Part P of the Building Regulations) — a qualified electrician is the safest route in every case.
Plug-in fixtures
Fixtures with a standard plug need no electrician: mount, plug into a socket, done. Check the product page to see whether a fixture is hardwired or plug-in before ordering.
Before installation
Always switch off power at the consumer unit before any work on wiring. Check the ceiling fitting is rated for the fixture's weight — heavier chandeliers may need reinforced fixing. In bathrooms and wet zones, use only fixtures with the appropriate IP rating for the zone.
Sloped or vaulted ceilings
Pendants and chandeliers need a sloped-ceiling compatible canopy on angled ceilings. Check the product page for compatibility, or email our support team with your ceiling angle — we're happy to confirm before you order.