Why you aren’t using temperature data enough.

So here’s the thing: temperature data is the most accurate, cost effective and easily available metric of comfort for your staff and assets. It also has a crucial relationship with productivity, energy consumption and efficiency. So why aren’t you monitoring it more?

You might be relying on your BMS to tell you if your colleagues are sweating or shivering. Or monitoring comfort complaints as a metric of how things are going. As a second line of defence most facilities professionals have a thermometer in their tool box, ready to settle disputes at the point of conflict. But for most people, that’s it.

Allow us to convince you that this is a wasted opportunity. Allow us to convince you that there is a lot more to temperature than dealing with ‘too hot/too cold’ complaints.

Why you aren’t monitoring temperature enough

We don’t blame you. Temperature data as it’s presented today generally has some significant drawbacks:
1) it’s monitored in the wrong place,
2) it’s monitored using equipment that is inaccurate, expensive and requires maintenance,
3) it’s not interpreted helpfully (or at all),
4) there isn’t enough of it to answer the really interesting questions

These drawbacks mean you can never be completely sure if complaints are due to a system problem or colleagues’ personal comfort level. And that HVAC systems can drift a long way from their optimum set up, wasting energy.

Why these problems are worth fixing

Monitored properly temperature has some unique attributes

1) it’s the most important measure of your actual comfort, directly related to productivity
2) heating and cooling is one of the most expensive elements for most organisations. 20% off your HVAC requirement is likely to give you a much higher return than 20% off your lighting budget
3) it’s affordable. Measuring temperature is a well understood problem and the technology is cheap. Why spend £800 or £1000 on purchasing and integrating a new submeter for a single floor when for half the price you can not only get data on a single point but on every desk cluster or fan coil unit, allowing you to pinpoint exactly where and when the problems are occuring.

 

Why should monitoring heat help you save energy?

Heating and cooling is one of the largest energy uses in most commercial buildings

It’s all about efficiency – maximising your heating and cooling for minimum input. In an ideal world you would measure both input (meter data) and output (temperature achieved for that meter data) and we advocate this for a true understanding of your estate’s heating efficiency. But if you can only do one we think you should do output and here’s why:

– in every case you will have meter data anyway, from which you can make some gross deductions about consumption trends.
– meter data can tell you nothing about the experience of your colleagues. The most effective way to save energy in heating would be to turn all heating systems off, but that is not the goal of the game. The goal is to deliver just enough heat/cooling to make a comfortable work environment at the time it is needed
– meter data can tell you nothing about the location of wasted energy. It lacks context – where the heat energy is being used, whether that space is occupied, if there is an extra load on the building’s fabric. Adding location and time to heat data allows you to begin to see the context and gives you important clues about what to do next

Smart meters are great – we should know, the team at Purrmetrix has been responsible for many successful smart metering products. But here’s what they can’t tell you: they can’t tell you where your inefficiencies are occurring and what else might be happening in the building that is relevant. PurrMetrix can.

If we’ve done enough in this post to convince you to take another look at temperature data, then sign up below for our occasional series on using temperature data for fame, fortune and better facilities management.

Can temperature data save your building?

A short course on using data to improve the performance of your building. And the people in it.

 

Fixing Social Housing with Technology – how hard can it be?

10 million people. That’s how many of us live in social housing in the UK: nearly 20% of our housing stock is owned by social landlords.  With nearly 4 million homes to operate, they face a formidable maintenance task and, in the main, they’re trying to do it with out of date tools – housing management systems straight out of the 1990s, multiple incompatible processes and a mass of silo’d data.

We know how to use technology – but does our landlord?

So in a world where us civilians are coming to terms with Smart Homes, even if we don’t have a clear business case, why aren’t social landlords engaging with technology? It has the potential to massively increase the efficiency of their business or even completely restructure the way housing is delivered. Imagine a housing provider who provides a platform for tenants to self manage their own properties – or a housing provider who rolls provision of all utilities and social care into the rent.

More practically, using the right analytics, imagine a housing provider who can identify and diagnose problems with a building’s fabric or systems remotely and ensure the right team, with the right tools, are deployed to provide the right solutions. Or using the same data to single out the homes that are eligible for funding for improvements.

This is a future that HACT – the Housing Association Charitable Trust – wants to create. Faced with substantial challenges over the next five years – cuts in benefits budget, the escalating price of housing – HACT knows the social housing sector needs to embrace innovation to survive so they have been digging into the barriers and challenges that are slowing progress. Their new manifesto (Is Housing Really Ready to Go Digital), identifies three barriers to change and what can be done about them:

Little visible leadership and accountability for technology at board level. Consequently tech is generally treated as a cost item, rather than an opportunity for fundamental change. Worse, where technology projects are commissioned, there is little embedded expertise in what can be delivered or how to measure accountability.

As a result, an over-reliance on consultant-led change. Without clear leadership on the potential of technology, consulting projects tend to focus on rationalising existing systems.

Low understanding of the potential value of data. Although housing has a huge amount of data it is too poorly structured and tools for effective analysis are generally lacking.

HACT’s manifesto has practical suggestions for how to deal with these problems – starting with a programme to match UK digital leaders with housing provider boards, and supporting their involvement in the business transformations that can result.

For those of us living and breathing tech every day, it’s easy to underestimate the challenges involved in promoting tech initiatives in sectors like housing. Bridging the ‘Digital Governance Gap’ in housing is not only challenging, it could be transformative for millions of people. If you want to know more about how to get involved, check out HACT’s Digital page.

The business case for building analytics – some case studies

Buildings offer a wealth of data about their performance. Getting information from building data isn’t easy – Pike Research estimate that 80% of FMs only use 20% of the data available in their BMS.

A lack of time and training is certainly one barrier. Another may be that it is difficult to build the business case for the work needed to collect and make sense of all this data. To help with this, we’re assembling a list of good examples of building data analysis for a range of goals. These examples come from vendors of a variety of solutions all over the industry.

Next time you want to have a conversation with your FD about investing in data tools, hopefully this will give you some benchmarks.

Carbon Credentials: optimising BMS controls for VUS Hotels. Forecast to save £20,000 pa in first phase.

A study from University of California of four enterprises and university campuses focussing on attained savings  

IES: a project for Glasgow City Council using BMS and metering data that highlighted annual savings of £85,000. A more detailed write up is also available here.

Demand Logic: Potential savings of £390,000 for Kings College

Concept Energy Data: Real time data reduces energy by 7% in four schools

Optimised Buildings: A <6 month ROI from energy savings identified in a Financial Services HQ.

Got a pet project that should be mentioned here? Get in touch! As long as it involves using building data (and ideally has some quantifiable results) we’ll add it to the list.

 

 

 

Working out the numbers – how many sensors do you need?

Often, when we’re talking to customers they will ask us how many sensors they might need. This is a great question because it lets us talk a bit about the applications customers are using the sensors for.

Honestly, we don’t have all the answers on this because we’re still breaking new ground here. There are a lot of potential applications for Purrmetrix that haven’t been tested thoroughly. That said I thought it might be helpful to explain a few rules of thumb we tend to use in answering this question.

TL:DR – it depends upon what you want to achieve with your project. Contact us if you want to talk through the specifics of what you are measuring

How specific is your HVAC analytics project?

Many customers start working with us in exploration mode. They want to identify and pick apart all the problems in their estate. In that case we suggest a fairly high density to start with – a sensor every 10 sq m or one for every cluster of desks. So in a fairly average 60 person office we’d be thinking about 15 – 20 sensors.

In a case where you want to collect data around a known problem, it’s generally possible to be a bit more precise about the numbers, depending on the type of problem you’re looking at.

What sort of problem are you hoping to test?

If you are looking at problems with specific parts of your building services – for example in each fan coil unit – then you have a fairly obvious guide of one or two per FCU. Although kittens can be redeployed its always better in our experience to test all parts of the system simultaneously so allow enough numbers to do that.

On the other hand, you may be interested in how the building’s fabric is performing – how quickly certain parts of the building heat and cool compared with outside temperature. If you think you have generalised insulation problems then 3 or 4 sensors along each aspect can generate quite a lot of information on the rate of heat loss, although you should allow for more if the materials change significantly along each aspect.

Are you analysing or influencing?

If you are hoping to influence behaviour (whether to save energy or helpdesk time) then you need to be presenting data at the hyperlocal level for each person. The ideal extreme would be one for every desk or working area, but in practise we find that a sensor within the same 10 sq m is generally adequate. Remember they can always be moved to accommodate sceptics!

How are you displaying it?

Because monitors are limited in how many pixels they can display the webservice has limitations in the way it displays the image of your building/project, which will be sized to 600 px wide. This generally means it is tricky to display very large areas with a lot of kittens, or make very precise placement of kittens on a low scale (zoomed out) plan.

Screen Shot 2016-10-23 at 20.55.14

At this scale it can be tricky to position this number of sensors correctly.

If you do have a project requiring a high density of sensors then make sure you zoom in and use the largest scale plan you have.

How the temperature gradients work

The colour gradient between kittens is not a reflection of the actual temperature in the gradient but of the confidence that it reflects the correct temperature. We don’t vary the size of kitten icon or the spread of the colour gradient so its spread is determined by the scale of the plan or image you upload the kittens above appear to be covering a floor area of around 6 sq m.

You can make the kittens disappear from the plan to better understand what is going on. Do this by clicking the arrow to the left of the view titla:

Temperature map of office

In general we don’t recommend uploading plans of any building of more than 60 meters.

In summary

  1. You don’t have to get it right first time, because you can redeploy your sensors
  2. Size your order to your use – general exploration and influencing behaviour will take more kittens
  3. Don’t try and display too many kittens in one heatmap view. Use other views (graphing) for that.
  4. Talk to us if you have a problem building and you’re not sure what the right level of diagnostics might be.

Heatwave Hits The UK – What impact is that having in the workplace?

sun-clouds-blue-sky-14641020076aMAs an industry we spend a lot of time thinking about how we can save money on heating, reducing heat loss and plugging draft gaps in our buildings. If your heating breaks down or you have a very bad insulated building then most of the time the odd fluctuation in cold can be dealt with by putting a jumper or a jacket on.

What do you do when it’s too hot in the office?

Too hot in the office is hard to handle. In an office environment there isn’t really much that users can do to keep themselves cool. If you have a strict dress code you really don’t have any options, you still have to wear your suit each day. You might find it hard to concentrate, become very uncomfortable and even lightheaded or dehydrated in extreme cases.

office temperature and performance

Effect of Temperature on Task Performance in Offfice Environment, Olli Seppänen, William J Fisk, QH Lei (2006)

Extremes of temperature certainly affect productivity. There have been a lot of studies over the years looking at this issue – when you jam all the results together the overall effect seems to be a plateau around 21 – 23° and a decline in performance of about 1% for every degree above 25°

The good news is that there are seasonal effects. If your body is becoming acclimatised to 28° outside the office, it will tolerate slightly higher temperatures inside without too much impact on work performance. This might explain why a studies conducted in Florida by Cornell University found fewer keystroke errors and higher typing rates at 25°, where studies in Helsinki office environment identified more performance issues at 25°.

Office temperatures in the UK.

Sadly the UK is a lot closer to Helsinki than Florida, but this week week will see possible highs of 30 degrees. So what does this mean for our users? Well as you can imagine it’s hot in lots of your offices. During the last UK heatwave we saw temperatures of 39 degrees from one of our kittens!  We are talking about a normal office environment and thats clearly not comfortable.

Helpdesk and building managers across the country will be inundated with complaints about the heat. While we might be about to leave the cooling season and many FMs will be tempted to ride out the complaints, creating a more structured policy to deliver staff comfort has many benefits – and it doesn’t always have to mean a total overhaul of building services.

Temporary or permanent solutions?

It’s clear at times like this if you have a cooling problem in your building but relying on complaints doesn’t give you much data to identify what’s causing the problem or where the main problems are. Heatmapping using Purr’s system gives some hard data to help deliver staff comfort in a heatwave:

  1. Identity hotspots.
  2. Understand how well your air conditioning is working or isn’t!
  3. See where the heat in your building is coming from – for example solar gain or occupational gain.
  4. Find out if humidity is also an issue (with our temperature and humidity monitors).
  5. See if solar insulation is an issue – you could look to install blinds or solar reflective film.
  6. Identify where to prioritise temporary measures like fans, stand alone air conditioning units or even where to install more permanent units in the future.

In the UK we don’t always prioritise cooling within our homes or office as the common feeling is that we don’t get much of a summer so its not worth it. However as the climate becomes more variable creating a comfort policy that can deal with a problem that affects productivity and, just as importantly, morale, is going to become a higher priority.

If you interested in finding out more about our heat sensors and the insights you can gain from our services please contact us on 01223 967301 or help@purrmetrix.com

(Image with thanks to Public Domain Pictures)

Using onboard monitoring? Here’s four things you’re missing.

IMG_3382If your server, rack or cage is in one of the UK’s established and well run data centres you can probably guarantee that they are going to keep the temperature within a fairly well controlled temperature range (unless something goes very wrong).

You also probably already have onboard temperature monitoring in your servers, disk arrays and switches so I bet you have never thought about any other type of temperature sensing or even mapping.

But if you’re simply looking at onboard data the chances are you are actually missing out on a lot of interesting, actionable information. Lets talk about the useful stuff that we at Purrmetrix can help you learn.

1. Locating a Hot Spot.

When you look at your onboard monitors you get a number on a screen – maybe even a graph. But how – and where – does that fit in to the bigger picture and I mean that literally. By putting data into a heat map you can see instantly how that all fits in. Is the machine you are looking at the actual problem? Is it a wider issue in the rack with air flow? Is it one of the machines next to it? A picture paints a thousand words after all. You could use this information to help you to make a better informed choice about where to fit your next piece of kit or how to set up the next rack you buy. Untitled 2 (1)

2. Tracking access to racks

If you have 3rd party engineers accessing your kit for maintenance, replacing kit or just remote hands from the DC to check something out for you wouldn’t you like to know bit more about what they are up to? When they opened the door, which racks they accessed, how long they left the door open for while they walked away from the DC floor or even if they left the doors open when they left. Yes the data that you get from the kittens really are that sensitive as the picture below shows.Screen Shot 2016-07-12 at 10.29.24

3. Remedying problem rack conditions

So what can you tell from the kittens that we believe can help you find out a bit more about whats going on when a fault occurs: if the temperature of the air coming into the rack has risen, if the air flow is being obstructed, someone has been into your rack, the humidity (only with the temperature and humidity monitors) has got up which could suggest a leak or a liquid spill, heat from a next door rack is effecting your rack etc. You could set up alerting in your account so that you can be informed when things go out of your preferred parameters.

4. Analysing what went wrong

Lets say that you had a total network meltdown and you really didn’t have time to study exactly what was going on in your rack regarding temperature. That’s ok because you can go back and replay the data when you have the chance. You might not have been able to figure out what happened or why. Perhaps the same scenario keep cropping up and causing a disk to fail or kit a server to reboot. You could find that there is some small event that is causing the issue or even that now you know how it shows up on the data you could recognise it sooner, set up an alert and stop it from causing the issue before it starts.

The importance of time and space.

There are a lot of possibilities but only with the correct level of monitoring. To make sense of the data you need to have information on where it is coming from, as well as when, and you can’t get this just from your onboard sensing. It’s time to bring our thinking up to date.

kitIf you think all of this sounds interesting then ordering a starter kit would be great place to start. A medium bundle contains 1 gateway and 8 kittens, this would do the trick for one rack with 4 in the front and 4 in the back spaced equally from top to bottom. If you want to have a chat to us about your current step up, problems you think you may have and how best you can detect them using kittens then you can contact us on 01223 967301 or help@purrmetrix.com

Liz Fletcher is Purrmetrix’s project manager. After nearly a decade in IT, miles of cabling and gallons of tea she is currently dividing her time between Purrmetrix and the UKNOF Programme Committee.

 

 

 

 

It pays to pay more attention to temperature

Last week I had a great conversation with Roger Whitlock at Hoare Lea consulting engineers which raised an important question.

What’s the most important problem with poorly performing HVAC? Nobody likes wasting energy, but with energy bills at less than 5% of most companies’ revenue, it’s not that big a deal, right?

Wrong.

Because it turns out that a poor environment, particularly poorly controlled temperature, has a direct impact on productivity. And thus on the bottom line.

Getting office temperature right

This is not new news. Studies since the 1970s have consistently demonstrated a link between performance and temperature.

Some highlights:

Study 1 – A 2004 study in a call centre showing that temperatures above 25.4°C had the largest impact on productivity, beyond ventilation, CO2 levels and even staffing and shift length1

Study 2 – A 2009 laboratory study used a range of neurobehavioural tests to try and dig into the effects of temperature on more complex cognitive skills. The study found that motivated participants can maintain productivity for short periods (30 minutes) over temperature ranges between 19° – 32° c, and that moderate warmth can affect mental performance in some tasks, while cold temperatures can affect physical performance in other tasks.2

Study 3 – A 2004 office study showed a steady increase in keying (typing) rates from 20° – 25° and a decrease in errors.3

One temperature to rule them all? 

A 2011 meta analysis of these papers and others shows a steady and pretty consistent relationship between workplace temperatures and loss of productivity, with a broadly neutral effect between 20 and 23°c and a loss of about 1% of productivity for every degree either side of 20 – 25%

Effect of temperature on productivity

Temperature’s impacts on productivity come in a range of effects – from routine tasks taking longer with more mistakes, all the way to increased rates of absenteeism.

So if you put all of these studies together do they give the final word on what is the best temperature for workplace productivity?

Nearly – it seems there is a pretty narrow band where optimisation is likely to happen. They certainly make a strong case for taking temperature very seriously in any workplace, along with other factors in comfort like lighting, airflow and humidity. An important point here is that the subjects in most of these studies were properly randomised – different genders, wearing a range of clothing – meaning the results should carry over into a normal working population.

There’s a couple of points that aren’t clear yet. First the effect of acclimatisation. Does the external weather tend to increase peoples’ tolerance for higher or lower temperatures? With results from Helsinki to Florida, there does seem to be a small effect.

Secondly does this effect apply to all tasks? Many of the studies looked at administrative tasks where it’s possible to define how long something should take and what a mistake looks like. It’s obviously difficult to design similar tests for more creative or analytical work in realistic environments. But one big anecdotal clue here – there are very few offices where individual workers have complete control over their environments. The few that there are are in places where these workers produce extremely high value output and a mistake can be very expensive indeed – trading desks for example.

Getting temperature right in the real world

How does this fit with running conditioning systems in a truly efficient manner?

In a system where heating and cooling are split, the recommendation is to run a ‘dead band’ between the heating and the cooling to avoid them fighting. The heating is turned off at 20° and the cooling comes on at 24° for example. It’s clear from the research that the tighter you can keep the dead band, the more time your colleagues will spend in the productivity sweet spot.

And a tight dead band relies on tight control to avoid clashes between heating and cooling. If sensors are drifting over time, or the thermal load is higher than the original design, then buildings can be locked into a cycle of rapid heating/cooling that gives the worst of all worlds.

Reframing the temperature conversation

Nobody sets out to make an uncomfortable workplace. However maintaining the systems that keep our work comfortable is often treated as a low priority, because 1) there seems little quantifiable payback and 2) it is sometimes difficult to measure improvements. The result is that apathy takes hold and it becomes difficult to justify investment, especially where budgets are tight.

Perhaps it is time to reframe the conversations facilities managers have with the board. By producing evidence of better productivity (or raising awareness of the dangers of lost productivity) you can start to build a serious ROI for investing in better control.

For more ideas about how to measure productivity and temperature in your building without needing a scientific research grant, head over to our LinkedIn discussion on the Corporate Real Estate group.

Picture of the month: HVAC in hot weather

So summer is icumen in here in Cambridge. Here it is certainly following the traditional pattern of an English summer: three days of heatwave followed by a thunderstorm.

All of which has produced some hard times for the cooling systems in the facilities we are monitoring. Take this:

Air conditioning failure summer

July 1st was the hottest day of the year so far, with temperatures over 32° following on from a couple of days with both warm weather and many hours of sunshine. So not surprising that at 12.15 the HVAC in this office gave up under the strain and couldn’t be bought back online until 15.30.

Picking this apart raises some fun details and questions. It’s worth comparing that week to the week before. Here are the plots for the Monday, Tuesday and Wednesday with the temperature and sunshine plots for those days along side:

Air conditioning failure 29th JuneAir conditioning failure 30th JuneAir conditioning failure 1st July

And here are the plots for the same days (monday, tuesday, wednesday) on the preceding week.

Office air conditioning summer 3

Office air conditioning summer 2

Office air conditioning summer

In this case temperatures overnight in the preceding week were much cooler – you can see the cooling system is working for much less time in the morning to remove the heat. There’s no characteristic sharp drop in temp at 5.30 am.

By the time we get to the week of the 1st July though, external overnight temperatures have risen and the office is holding a lot of heat overnight. In the morning removing that heat is taking more and more time. Furthermore, evening sunshine on both the two preceding days has warmed a portion of the office (on the right hand side of plan) that has always had difficulty in removing heat, so the system was under an immense amount of strain.

Under the circumstances if the system was going to suffer a failure, this is the situation which is likely to trigger it.

After the temperature topped out at 28.2, the cooling was eventually bought back on line, but the damage was done: there was far too much heat in the building to be removed by the HVAC before it was turned off at 7.30 and another warm night overnight meant the repaired system had to work for a much longer period in the morning to remove it, churning away for twice as long as usual.

Lessons learned? If you have HVAC systems that are older and have already identified some hot spots, be ready to take drastic action if you have a period of warm nights and solar gain. You might be operating closer to the edge than you might think.

If you have similar troublespots in your facility and you’d like a better picture of how the summer is affecting them, contact us for a quote on a pilot deployment.

Thermostat wars – what if they’re not all in your head?

So we’re coming into the office air conditioning season after a warm dry spring. And that means it’s time for the annual crop of headlines about thermostat wars. Like this one, and this one and this one. Notice something similar with these?

That’s right – all of the ‘discussion’ about office temperature seems to be about the difference between people. Specifically, that men generally like it colder than women. Oh, and for some strange reason the ladies in marketing always feature as needing it hotter than anyone else.

Folks, I smell a giant, slightly sweaty, rat here. Of course, there are differences in how people perceive temperature. However, if you’ve had the pleasure of ploughing through the ASHRAE and CIBSE literature on temperature and comfort in offices, then you know that an immense amount of research effort goes into identifying a range of temperatures that works for the largest number of people.

So when you get surveys that suggest 60% of people are unhappy with the temperature in their office – cooling in summer or heating in winter – my conclusion has to be that its much more likely the problem is the HVAC.

Too hot and too cold. In the same office?

People disagreeing about office temperature and fighting over the thermostat makes good headlines. Truth is, they may both be right. Its completely normal for office temperatures to vary across the room. So Karen sitting under an air conditioning vent may well be freezing while Mick starts to sweat in the sun at the other side of the room.

And while humans aren’t very good at estimating absolute temperature, we have quite high levels of sensitivity to changes in temperature – anything over 1 degree in 15 minutes is generally detectable. So even quite small variations throughout the day tend to get noticed, particularly if they coincide with peaks and troughs in metabolism.

Why does my office temperature vary so much?

Temperature – and how it affects comfort – is a more complicated subject than it might first appear. If we break it down to its component parts it begins to be obvious why variations happen in buildings.

Perfect office temperature

Perfect office temperature – they don’t seem worried by convection

The basic physics of how heat moves around is probably familiar. Heat can be transferred from one thing to another by radiation (heat energy being transferred directly – like in sunlight), convection (heat being carried around in air or other fluid) or by conduction (transfer along a physical object like a metal spoon in coffee). In an office, radiant heat and convection are normally the two most significant mechanisms for transferring heat around, and these create the first set of challenges.

Because heat will move around a bit differently, depending on the mechanism. Unless you’re sitting in an office made of warm water convection is going to rely on warm air circulating around your office. On the other hand, any ‘body’ – a window, a wall, a desk, a laptop – that you can see will be radiating heat directly at you. If they are at a similar temperature to you this effect will be small, but once the mean radiant temperature gets more than 5 degrees out of whack to air temperature, you are likely to feel uncomfortable.

Since the biggest ‘bodies’ in any office are generally windows and walls, and since they are generally exposed to external temperature, being close to a hot window or a poorly insulated wall makes you very vulnerable to fluctuations in their temperature. And you might be freezing while Frank near the kitchen is toasty.

But wait, there’s more! Why your office’s temperature varies over time.

Do you like graphs? Of course you do. Here’s a fun one:

Measured temperatures in open plan office

Office temperatures Cambridge 7th – 27th April.

This is a graph of the temperature measured at multiple points across an open plan office for 19 days. Spot the two weekend periods (here’s a clue – look at the minimum temperatures). Why are they significantly cooler? It’s not just because there is no heating on. In fact the main difference is the lack of people. Occupation adds heat. A lot of heat. Each person gives out about the same about of heat as a 100 Watt lightbulb, and that’s before you add in the lighting and equipment that they need.

On top of that, there are long term trends that change how hot offices get, from cooler technology – computer monitors that use LED screens – to hot desking. So over the course of the day and over time you can expect to see the heat load (how much heat is generated) change a lot.

Surely my office heating and ventilation is designed to deal with all this?

Indeed it is. And in future blog posts we’ll have a look at some of the work on how zoning, building management systems and natural ventilation is helping.

However, as you can see, how comfortable you are during the working day is actually the sum of some complicated factors, and that’s before we get into activity levels, clothing, humidity, air speed and all the other issues that have significant impact on the working environment. A good building should compensate for many of these, but there are multiple reasons why they change over time, so regular reviews of whether the building’s heating and cooling is doing its job is always a good policy.

Not just telling the lady in marketing to put on another coat.

This is just the first in what we hope will be a series of posts about HVAC and comfortable buildings. Tell us what problems you’re having and we’ll make sure we cover them.