The provision of air conditioning had a profound impact on the overall level of service charges, a Jones Lang LaSalle report has found. Service charge costs in buildings with air conditioning at €67.58 per sq m (€6.28 per sq ft) were 14 per cent higher than the overall average for Dublin and 28 per cent higher than office buildings in Dublin without air conditioning.

The average service charge for buildings without air conditioning was €52.73 per sq m (€4.9 per sq ft). This figure is 11 per cent less than the overall average for Dublin. Buildings without air conditioning tend to have much lower costs for power, light and security costs in addition to the absence of air conditioning costs, the report noted.

The definition for an air conditioned building used in the service charge analysis was buildings "in which cooling and heating are provided in the majority of the lettable space via a central plant installation".

The report found that older air conditioned buildings have the highest service charges while more modern non-air conditioned buildings have some of the lowest service charge costs. Buildings built between 1980 and 1990 had average charges of 85.81 per sq m (€7.97 per sq ft) while those built between 2001 and 2004 without air conditioning had average service charge levels of 39.14 per sq m (€3.64 per sq ft).

The most expensive components for buildings with air conditioning are power and light costs (12.05 per sq m, or €1.12 per sq ft) and security costs (11.69 per sq m, or €1.09 per sq ft). The comparable figures for non-air conditioned buildings were 4.37 per sq m (€0.40 per sq ft), a 63.7 per cent difference, and 9 per sq m (€0.84 per sq ft), a 23 per cent difference.

There are significant differences between other service charges in air conditioned versus non-air conditioned buildings - the combined heating/cooling costs being the primary consideration.

Heating and air conditioning costs in buildings that used both were €11.35 per sq m (€1.05 per sq ft), compared to just €4.81 per sq m (€0.45 per sq ft) in buildings without air conditioning, a 57.6 per cent difference.

There were marked differences in other charges. For example, a 12 per cent difference in the cost of cleaning (€10.93 per sq m, or €1.02 per sq ft for conditioned, 9.62 per sq m, or €0.89 per sq ft for non-conditioned), but almost all other parameters balanced in the other direction with non-conditioned properties more costly than conditioned.

For example, building staff/porterage costs were 13.2 per cent higher in non-conditioned buildings on average (€7.46 per sq m or €0.69 per sq ft versus 6.59 per sq m or €0.61 per sq ft), maintenance was 18.6 per cent higher (€5.20 per sq m or €0.48 per sq ft versus 6.17 per sq m or €0.57 per sq ft), lift escalators were 26.3 per cent higher (2.17 per sq m or €0.20 per sq ft versus 2.74 per sq m or €0.25 per sq ft) and car-parks were 46.4 per cent higher (0.28 per sq m versus 0.41 per sq m).