It’s not much fun feeling cold. Cranking up the heating isn’t an option for many and, in fact, it may even make the situation worse.
So what is the smart thing to do to avoid ‘feeling cold’?
In this post I aim to shed some light on the physiology of ‘feeling cold’ and link that understanding to common heating problems and misconceptions. You’ll be pleasantly surprised how easy it to sort out your space so you feel comfortably warm.
When we say we ‘feel cold’ what we are experiencing is an uncomfortably high rate of heat loss from our body. This is a fundamental point. Controlling the rate of heat loss is key to getting warm again.
Through our metabolism we generate heat internally. This is natural.
It follows that we need to loose heat in a controlled way to avoid over-heating. Our bodies are very adept at making the necessary adjustments – for example blood vessels dilating and sweating – so we don’t over-heat.
Conversely, in a cold environment the body can compensate to some degree to avoid excessive heat loss. But there comes a point when you start to ‘feel cold’.
This is miserable experience if it goes on for any length of time. But the way we heat our homes can make it very difficult to get warm again.
Amazingly the number one culprit is traditional central heating with wall mounted radiators.
Most of us have this type of central heating and it represented a massive step forward as a ‘mod con’ (or modern convenience) when it became popular in the ‘fifties and ‘sixties. But it’s not without its problems as we’ll see.
The biggest problem is that a wall mounted radiator is really a large convector heater with about 70% of the heat transfer to the room being convection. By this I mean air in contact with the radiator is heated through conduction and then goes off on a journey around the room (convection) so we are surrounded by the warm air.
We all know hot air rises, and we may also remember from physics lessons that warm air can carry more moisture than cool air. So as this heated air rises to the ceiling it picks up moisture from every surface it passes over. This includes our skin and has a drying effect.
When it reaches the ceiling it gets pushed across to the far wall by the freshly heated air rising up behind it.
As it cools it starts to sink back to the floor, and, as it does, it gives up the moisture it picked up earlier. If the outside walls and windows are cold, this is often seen as condensation. Condensation problems can lead to mould growth which is very hard to get rid of and can cause respiratory problems.
So we can see that convection heating is undesirable as it dries the skin and can lead to condensation (and mould) problems.
But what might not be immediately apparent is that this convection process is actually contributing to us feeling cold. The relatively cool air at floor level, as the convection current circulates, leaves ankles and feet feeling cold in relation to the face and hands.
This cold feeling is made worse because the rate of heat loss is speeded up by air movement. This is the same as the wind chill the weather man talks about and, remember, we want to control the rate of heat loss to avoid feeling cold.
Relying on convection for your heating means relying on air movement. Add that to the fact we prefer warm feet and a cool head and we can start to see how convection gives us the opposite of what we want to feel comfortable and is a bad way to heat your home.
We can’t just ditch the central heating but the simple act of turning down the thermostat has a miraculous effect. It minimises convection currents thus reducing cold draughts on feet and ankles, limits the drying effect on the skin, and gives us cooler air to breath.
But as the air temperature will be cooler we will likely want to introduce a secondary source of heating.
We obviously don’t want a conventional portable heater such as an oil filled radiator or fan heater. Conventional portable heaters like these all rely on convection and air movement. They also tend to be noisy, unreliable, expensive to run, and clutter up the room!
The answer is a radiant heater. But I don’t mean a single ‘point source’ heater that needs to be positioned carefully so that is neither too close nor too far away.
What I mean is a radiant ‘area heater’. A radiant ‘area heater’ gently acts over a wide area giving a comfortable space for us to spend our time in.
Area heating works by warming a surface to become a ‘radiator’ in the true sense of the word. This ‘surface radiator’ will warm our clothes and other cooler surfaces in the area without warming the air. (In time the air temperature will rise but only because the air has been in contact with these warmer surfaces.)
The surface radiator will also reduce the rate of heat loss from our skin. Tests have shown that using the floor as a surface radiator at a temperature of around 27ºC is most comfortable leaving us feeling neither too hot nor too cold. This, of course, is the principle of underfloor heating.
A breakthrough in design means there is now a plug-in heater that slips under a rug and so is completely out of sight. It can be placed on any floor surface – carpet, laminate, wood, or tiles.
It warms the rug so the rug becomes a radiant surface turning it into an ‘area heater’. The whole area of the rug is gently warming everything on and around it.
The warmth is at floor level, just where you need it, leaving the air undisturbed. So no draughts, no condensation problems.
This under-rug area heater is called RugBuddy and is available exclusively from BeWarmer Limited.
RugBuddy customers report being able to turn down their central heating by up to 3degC saving them £225 per year according to the Energy Saving Trust. A RugBuddy uses much less electricity than other portable heaters and only costs a few pence per hour to run.
You can read more by visiting http://www.rugbuddy.co.uk.
Guest post by William from Rug Buddy