Distance Between Street Lighting Poles: What It Depends On and How to Calculate It

Why there is no single spacing norm in metres

DBN V.2.5-28:2018 “Natural and Artificial Lighting” does not set pole spacing. What it sets is the required luminance or illuminance of the road surface, depending on the street category (A, B, C) and traffic intensity; the category table is in Street and Road Lighting Norms.

The spacing that meets that requirement is worked out for a specific luminaire, because it depends on the light output, the light-distribution curve and the mounting height. A table of “street category versus spacing in metres” that ignores the luminaire can therefore be no more than a rough guide.

What the distance between poles depends on

• mounting height: the taller the pole, the longer the stretch of street one pool of light can cover;
• light distribution of the luminaire: a wide beam lets you space poles further apart, a narrow one calls for closer spacing;
• width of the strip to be lit (carriageway, pavement, path);
• street category and the luminance or illuminance required under DBN V.2.5-28:2018;
• pole layout: one-sided, staggered or opposite two-sided, or central;
• obstacles along the route: trees, buildings, intersections, public-transport stops.

A practical rule: spacing as a multiple of mounting height

Until you have a lighting calculation, use a rough ratio for a first estimate: pole spacing of about 3-4 times the luminaire’s mounting height. The exact factor depends on the light-distribution curve of the specific model and on the uniformity required, so treat it as a guideline, not a norm.

Practical spacing grows with pole height. For a park with 4-6 m poles it is roughly 12-24 m, for a street with 8-10 m poles about 24-40 m, and for a road with 11-12 m poles about 33-48 m. The final spacing and luminaire power are confirmed by a calculation for the chosen model.

A worked spacing example

Take a local street (category C under DBN V.2.5-28:2018) with a 7 m carriageway and poles on one side only. By the practical rule, the mounting height for a one-sided layout should be at least the carriageway width, so we choose an 8 m pole (UMO-8 range). At 3-4 times the height, spacing runs from 8 x 3 = 24 m to 8 x 4 = 32 m, a rough range of 24-32 m.

Now suppose the same street is wider, say 10 m, with a staggered two-sided layout. The mounting height comes from the rule that the strip width should be up to one and a half heights: 10 ÷ 1.5 ≈ 6.7, so at least 7 m. District streets normally get poles of 8-10 m (UMO, UKO or DMO series). Spacing on each side stays within 3-4 heights, roughly 24-40 m, and the poles on the two sides are offset from each other.

This is only good for estimating the pole count and project cost. The final spacing, power and luminaire model come from a lighting calculation. Send us the street width and category and we will help you choose a solution. You can run a rough selection by these rules in the lighting pole selection calculator.

Pole layout schemes

• one-sided: poles on one side of the street only, for narrow roads and paths;
• staggered two-sided: poles alternate from one side to the other, which gives more even light on wider roads;
• opposite two-sided: poles face each other across the street; used on wide roads and highways;
• central: poles on the median strip, for large areas and wide roads lit on both sides.

The layout also changes the spacing. To reach the same illuminance, a one-sided layout needs poles closer together than a staggered or opposite two-sided one, because the light overlaps from one side of the street only.

Parks, courtyards, intersections and pedestrian crossings

Parks, courtyards and footpaths get lower poles (3-6 m), spaced more closely than on streets and roads: roughly 12-20 m, depending on the height and the luminaire model.

At intersections, pedestrian crossings and public-transport stops the required luminance is higher than on the neighbouring stretch of street, whatever the category. Spacing there is usually reduced, or a separate pole with its own luminaire is placed right at the crossing. More in Pedestrian Crossing Lighting.

Common mistakes when choosing pole spacing

• one spacing used on stretches of different width: the street is over-lit where it narrows and has dark gaps where it widens;
• “park” spacing (12-20 m) on a street with tall poles, so illuminance between the poles drops below the norm;
• no extra pole or luminaire at an intersection or crossing that needs higher luminance;
• spacing chosen without checking the light-distribution curve of the specific luminaire; the 3-4x rule of thumb does not fit every model;
• bends in the road ignored: on curves the spacing has to be reduced, otherwise dark zones appear on the inner radius.

What spacing means for pole count and cost

Tighter spacing means more poles and a costlier project, but more even lighting. Wider spacing cuts the number of poles, yet it calls for more powerful luminaires and taller poles, and those cost money too. Where the sensible balance lies is settled by a calculation for the specific street. How much a pole of each height and range weighs is in Lighting Pole Height and Mass: Table by Range.