The challenge to stay warm and fight COVID as we open windows in winter

New advice released from the Department of Health on 18 November 2020 encourages people at home to open windows in winter and increase ventilation in the hope that this can lessen the risk of covid. The government department reports that being in a room with fresh air can reduce the risk of infection from particles by over 70%. The virus is said to linger in the air in spaces with no fresh air which, in turn, leads to an increased risk of people breathing in infected particles. This risk can be minimised through frequent ventilation of enclosed areas, window opening being a simple, yet effective action to improve the flow of fresh air indoors.

Current advice is to either open windows regularly for short bursts of circa 15 minutes at a time or to continuously leave windows open a small amount.

With the colder winter temperatures upon us it is also important that comfort levels at home are maintained, alongside this advice to increase ventilation. This advice, on the face of it, therefore feels somewhat harder to implement as we contemplate the colder winter ahead.

manage comfort and ventilation with open windows in winterWhether you can follow the advice sensibly or not, actually depends on how your home is heated.

Our sense of comfort indoors is said to be the average of the air temperature and the heat being radiated directly by the environment around us.  If our heating is primarily convective (heats the air) then the above advice – and our own comfort – cannot be easily met without huge wastage of energy.   Hot air will easily escape through any open windows and draughts, resulting in both the room and the people within it feeling cold. (This is exactly why convection heating is not used for heating people outdoors.)

However, if the heater is Infrared (i.e. primarily radiant – transferring heat directly from the heater into the fabric of the room and its people), then it matters less, that the air temperature is being lowered by opening your windows. Your sense of comfort is still being maintained by the radiant heaters AND you can follow the advice to keep air circulating through your house and minimise on energy use at the same time.

Infrared versus Convection: Heat Transfer Fundamentals

Infrared is the same form of heat as that from a wood burner or an aga. It keeps the thermal mass of the building warm and this then radiates back out, keeping the environment warmer.  So this type of heating is far more tolerant of opening windows and letting fresh air circulate.

It is important to note that opening windows will always result in higher energy consumption from your heating, but infrared heaters offer a more effective option to maintain comfort while allowing the air circulation because of the greater radiant effect you get from them.

It is worth noting that most modern heating controls incorporate a ‘open window detection’ technology as part of Eco Design Energy Saving Regulations. This feature can be temporarily disabled in some rooms in light of the current guidance to keep windows open or it can be left on in others so you don’t use too much energy in rooms you don’t need to.

Herschel heaters can be used to heat an entire room or as supplementary, top up heating in any given room. The Herschel Select XLS white panel range is available with quick plug and play set up and offers DIY installation for a simple, quick and effective heating solution for homes. Follow advice to improve the circulation of air within homes, open windows in winter and manage comfort levels with radiant heating.

Posted on