How to keep cool - The Expert’s tricks that won’t cost the Earth

You’ve heard a lot recently about the heatwave in the UK and across the world and how likely temperatures like these will become normal. So that means that we need to get better prepared and re-learn age-old tricks with maybe some new technology so we can handle these hot months!

We know a thing or two about keeping cool over the last few decades, as we’ve designed, installed and maintained all manner of air conditioning systems for nearly 40years, so we’ve decided to share some of those trade secrets to keep you cooler on these hot days! Better still, most of them won’t cost you anything.

This will take about 9 minutes to read so if you don’t have that time, then jump to the bottom where we’ve listed them out.

Keep the outside, outside

If the air is warmer outside than inside, then keep those doors and windows shut. This will slow down that hot air from coming in and getting trapped in the rooms.

Hot air rises

We all know this, so keep that in mind as hot air can move around inside a building quicker than you think, so keep all your internal doors closed too. Throw in a staircase or a high ceiling area and hot air will collect at the top really quickly. If you have to use the space up there, then open a window to let the hot air out. Keep in mind that what that does is draw air in from the bottom (just like a chimney), which may well be warm air from outside.

Draw your curtains or blinds

It’s a lovely sunny day and we’re asking you to draw the blinds; I know! By doing this though you’re reducing the ability for the sun to heat up the surfaces inside which then, in turn, heat up the room like little radiators. Just touch the floor that’s in the sun and then feel the areas in the shade and you’ll see what we mean.

Don’t put those ceiling fans on straight away

This does seem counterintuitive, but hear us out. Its early in the day, it feels cool in the room, great let’s get the fans on for a nice breeze…hold on there! Remember hot air rises so that air up by the ceiling fans is warmer than that you’re standing in. You don’t want to push that warmer air down, do you? So, the best thing to do is to leave them off, enjoy the cooler air you’re in until that warms up and then turn the fans on to get that breeze. (tip - those fans are great in the winter to gently push the warm air you then want down towards you)


Drinking a hot drink

Our Finance team swears by this! Another counterintuitive action, but they say that by drinking a cup of tea, the body sweats and therefore cools down. According to the University of Ottawa’s School of Human Kinetics in a 2012 study, they said ‘if you drink a hot drink, it does result in a lower amount of heat stored inside your body, provided the amount of sweat can evaporate’. Just by doing a quick search online, you’ll see lots of people saying this doesn’t work. Well, the only thing to do is try it to see!

Insulation is your friend

It’s for much more than just keeping you warm in winter. Basically what insulation does is slow down the equalising change in temperature, which is the inside trying to become the outside temperature. So on these hot days, well-insulated areas will keep cool for longer, but once warmer air gets inside, it will keep hold of that warmth so keep an eye out for that.

Hard surfaces are great

We could talk about thermal capacities and conductivities, but you’d switch over to Facebook quicker than a fake news re-post, so we’ll keep it simple. Surfaces like stone floors keep cooler for longer, as they hold on to the cooler temperature overnight. If you want a great example of this, go into an old church in the morning.  


Ice in a hot place

This is another that makes so much sense and yet we probably forget we could. Not so the Special Projects team, who excel at the simple cost-effective solutions, because they think using a thermos flask you’d normally have hot drinks in, actually works just as well for storing ice or cold drinks all day long, no matter where you are.

Get the outside, inside

Ok, we know that might confuse you, but if the outside temperature has dropped below the inside temperature, like in the evening, then get those windows and doors open! And then…

Point your fan outwards

Once you’ve got that cooler air, let’s push it around as quick as we can. There’s an effect called cross ventilation where air moves through a building naturally, but why not help it on its way. One side of the room or building, open a window then go to the opposite side and do the same. Now, try to see which one the air is coming in from (the wind direction should help here) Then, place a fan at the other window pointing outwards, to blow the air outside. Now you’re pulling cooler air from that other window, right through the place with just that fan! (if it’s a big area, you may need another fan next to the window with the air coming in, to help push it through)  


The Ice Cooler

It’s a simple idea and one that anyone could easily make at home. The premise is that moving air over ice will cool it, then when it passes over you, you cool down. Simple. Here’s one that we up-cycled out of an old polystyrene packaging box something got delivered in, an extract fan and some cardboard tubing from a roll of paper. Our Maintenance team thinks this is one of the best ways you can do it for free and suggest you can also do it with a suitable wire container with some freezer blocks stacked in it and placed behind a desk fan. Pop it on high speed and enjoy! Don’t forget a little tray to catch any drips.  


The Evaporative Cooler

This one is straight from our Installation team and they’ve gone for a really simple and effective solution using things that most of us would have already. Taking a fan and placing it behind a wet towel draped over a clothes airer that then makes an air tunnel and placing a plastic container full of water with pinholes in it to keep the towel damp; enjoy the cool air that comes out!

Watch out for thermal shock

This is the phenomenon when something quickly moves from one temperature to another and the effect it has. On a person, its how you feel when you walk out from an air-conditioned area to a hot outside; like from a supermarket to a hot car park. It can hit some people quite hard. When it does, it can make you feel woozy and make you break out in a sweat because your body is suddenly warming up really quick. So, try to ease yourself into that hot car park by sticking to some shade a little longer or having a cold drink; just try to slow down the heating up!

A professional solution

There is only one way to really stay cool in a building and that’s to cool the inside down. Air conditioning will make all the difference and its not as expensive as you might think. Of course, then people say that AC costs a lot to run; well that isn’t quite true, it’s actually one of the most efficient uses of electricity there is. Then if you add a solar panel into the mix (that are getting cheaper each year) and you’re using free energy from the sun on a hot day, to cool your building down. (don’t forget, the modern systems can give you heating as well for the winter).

Have a breeze

If all else fails and you can’t do much else, just by having a breeze across you will help you cool down. Just by the fact that you have air moving over your skin means that heat is taken away more and you feel cooler. (It’s the evaporative effect). It’s exactly the same when you’re sitting on a beach, even directly in the sun and yet you still feel cooler if it’s windy.  


The Condensed List

This is the short version, if you don’t have time to read the above yet:

  • Keep the outside, outside - shut those doors and windows to stop the warm getting in
  • Hot air rises - keep internal doors closed too and open a window in high ceiling areas
  • Draw your curtains or blinds - it reduces the amount things inside heat up
  • Don’t put those ceiling fans on - it can push warmer air down to you
  • Drinking a hot drink - can make you sweat more so evaporative cooling happens
  • Insulation is your friend - reduces the inevitable change in temperature
  • Ice in a hot place - use a thermos flask for ice or cold drinks
  • Get the outside, inside -when the air is cooler outside, let it in
  • Point your fan outwards - helps draw that cooler air through if done as suggested above
  • The Ice Cooler - air cooled by ice, blown over you
  • The Evaporative Cooler - air cooled by water, blown over you
  • Watch out for thermal shock - don’t go straight into a hot area from a cold one
  • A professional solution - proper air conditioning
  • Have a breeze - just air blowing over your skin helps a lot  


We hope this has helped and given you some ideas to try out. Just remember there is lots of good advice out there from recognised experts, so get researching, as this hot weather could well be here to stay.  


For you:
Official NHS site

For your best friend:
Official RSPCA site  


We’d really love to hear which of these suggestions have worked for you and for you to share yours too!

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