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A heated debate on office temperature: Part 1 – Autumn/Winter

Posted in: Facilities Management

At some point in your personal or professional life, you’ve probably been involved in the age-old debate of what temperature to set the thermostat.

Across the world, buildings have been set to what is considered to be the optimum temperature. It’s usually around 22 degrees and it’s been that way since the 1950s.

The problem is, this level was actually based on the thermal comfort level of a 44-year-old man.

No two people are likely to have the same level of comfort when it comes to temperature. Everything from age, size, gender and what you wear will factor into it.

Is there an optimum temperature for the workplace?

gloved hands typing

Here’s what the law says about workplace temperature, according to the Health and Safety Executive:

“Temperatures in the indoor workplace are covered by the Workplace (Health, Safety and Welfare) Regulations 1992, which place a legal obligation on employers to provide a ‘reasonable’ temperature in the workplace.”

A suggested minimum temperature should be at least 16 degrees Celsius (13 if work involves rigorous physical effort) and there’s no guidance for a maximum temperature.

However, studies have shown that if temperatures reach 33°, the temperature can affect productivity and decrease it by up to 85%.

Cold executive working in winter

Given that an outrageous amount of energy is used to heat and cool buildings, what can you do as a business owner to ensure that everyone feels comfortable with the least impact on your monthly costs?

We were asked this very question by a client recently.

What’s the best way to regulate office temperature in autumn and winter?

Our client’s head office has 2 open plan floors with various enclosed meeting rooms and offices.

The air conditioning system is ‘owned’ by the landlord and their advice was to auto-set it to 21 degrees. Despite this, they received complaints on a daily basis about it being both too hot and too cold.

This is a classic issue and one we have come across on many occasions. It’s especially common in the autumn when a building needs heating in the morning and cooling in the afternoon.

The reverse is true in spring but we’ll cover that in a blog closer to the time.

Is there an easier way to regulate the temperature?

We think so.

The Goldilocks Zone

Solar system with main planets in flat style

The Goldilocks Zone refers to the habitable zone around a star where the temperature is just right – not too hot and not too cold – for liquid water to exist on a planet.

This is the elusive zone where a planet would need to sit in order to support life.

Finding this happy medium is as difficult in the workplace as it is in space!

While the landlord’s suggestion is a reasonable one, 21 degrees is too cold for many people.

If you were to set it to 23 degrees, that’s likely to be too warm for some staff.

Ironically, in our experience, setting it to 22 degrees results in even more complaints because this is too cold for many that can feel a draught and too warm for others when the system modulates between heating and cooling.

So what’s the solution?

The first steps that we would take would be to look at the building.

Heat gain and heat loss

Heat Leak Infrared Detection

A number of things can contribute to temperature swings including natural ventilation from windows and vents through to the thermal ability of the building.

The AC system may need some adaptations but let’s assume that you work in a typical office environment that is not overly populated with a mid-range air-conditioning system and adequate thermal properties.

Here’s our suggestion for an office environment:

Inform Staff

Firstly, publish a staff communication of what you are going to do. Let them know that the aim is to improve their comfort as well as save energy.

Implement a 19-23 rule

Tell staff that complaints will not be accepted between the temperatures of 19 degrees and 23 degrees because temperatures will fluctuate. Put out a staff comments box on reception for feedback.

Be mindful and layer up

Remind all staff that they are working in an office where some people are warm whilst others might feel a chill.  Therefore it is important to regulate your personal comfort by having a layer of clothes that can be put on and removed!

Don’t set it to Auto

Setting the air conditioning to Auto will result in temperature swings that may be uncomfortable for many and in autumn this is energy inefficient.

AC systems could also ‘fight’ each other in the Auto mode. One unit might switch to cooling because the unit next to it is on heating, causing bigger temperature swings.

Digital Thermostat set to 19,5 degrees Celsius on white wall

Set the AC to Heat Only

Come in early (or even better, use the timer function), set it to 19 degrees and let it heat up the office before the first starter arrives. Set the timer so that the AC system stops mid-morning.

The natural build-up of heat from PCs and staff will add to the temperature as the day goes on.

Use free cooling

It might seem contradictory to open the windows in winter but it can be a lot more efficient than changing the thermostat.

Ideally, you will have a ducted ventilation system (separate to your AC system) for your office where the outside air temperature can be tempered before it vents into the office.

Did you know that the average UK temperature (London) between October and March is 8 degrees Celsius?  This means we have a free resource of cool air when required.

glass facade with opened windows on a modern building

If the temperature rises above 23 degrees, permit staff to open windows slightly or adjust your ventilation system so that the temperature in your office can be within the 19-23 range.

Just make sure that they stick to the 19-23 rule. This should avoid any large temperature swings.

Everyone’s thermal comfort level is different

It’s worth pointing out here that this is a suggestion based on our own experience.

There are probably just as many facilities management professionals who would baulk at the thought of taking the AC off the Auto setting.

Equally, the heat gain and heat loss of a building will impact on the comfort levels within it. With that in mind, we’d always suggest looking at the heating and ventilation systems in a building before taking any drastic action.

Ultimately, the most important thing to consider when it comes to the heated debate of temperature in the workplace is creating a culture that recognises the fact that not everyone is going to be happy all the time.

In our experience, it is possible to save energy and control expectations regarding comfort to achieve a happy office.

This is just one approach that could be taken. If you’d like to hear about some other solutions, get in touch with our experienced maintenance management team today.

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