Is It Cheaper to Leave Your Heating on Constantly?

hello i'm roger bisbee from the skill builder channel i just want to do a very quick video for you and it's answering a question that we get asked lots and lots and that is is it cheaper for you to leave your heating on your central heating on all the time or switch it on and off on the timer and the simple answer is no it's not cheaper to leave your heating on all the time for those of you who want to know why i've come to that conclusion generally apart from the solar gain and things like that there's no such thing as free heat if your boiler oil is on or your electric heating is on or your heat pump is on you are paying money for it now it will switch on and off on a thermostat so it will just tick over and once you get the heat of the house up to the desired temperature just switching that heating on and off will maintain that temperature and keep the house lovely toasty warm and comfortable even if it's really well insulated over the course of a day it will lose heat heat will always travel to cold so if it's colder on the outside simple physics tells you that that heat will be migrating through the walls through the windows and through the roof to the outside everything depends on how fast that happens the more insulation you've got in your house the slower that heat loss will be so when people come around and do a heat loss calculation on a house what they're looking at is how much insulation you got in your walls the thickness of the walls whether your walls of cavity whether your floor is insulated whether your loft is insulated whether you've got double glazing and what standard that double glazing is up to and also the very very important thing of draft proofing all these things come into play with the best will in the world somebody comes around they look at your property okay they're in a train surveyor or whatever but they can't do a really accurate heat loss calculation on your house simply because of what we call a performance gap and that is areas where the insulation is not working as well as it might areas where the draught proofing is not working as well as it might now these don't really come into play until the weather gets really cold and then you notice that little draft or you notice a cold spot on the house or sometimes you notice a bit of mold building up in the corner of a bedroom or something like that where the bedroom's a little bit cold and you're finding that cold bridging is making mold appear on the wall when that surveyor comes in he takes those heat loss calculations at face value he believes that the cavity wall insulation is continuous around the cavity and there's not going to be gaps in it which they very often are and all those kind of things and he comes up with a figure and maybe he or she i should say adds a little bit of a margin to be on the safe side and then you end up with your heat loss calculation now that heat loss calculation is also dependent on whether you're heating the other rooms so in other words if you take a house like this one for example where we've got a fairly large kitchen a lounge and a front room and so on the heat loss calculation that's done on this kitchen allows for three outside walls that wall there that leads through to the other room we assume that that room is heated to more or less the same temperature as this room so there is no heat loss through that wall from one room to another now it's very important because if you like me go around turning the rooms off that you're not using in other words we've got bedrooms which only get used once in a blue moon we turn the heating right down in those bedrooms we just have it ticking over on the thermostatic radiator valve and that way we save money but it does throw the heat loss calculations out for the rooms which are adjacent to that room because suddenly you've got a room which is colder than it otherwise would be so you will have a heat loss from that room to the other room it's one of those things where some people would say well keep all your heating on keep all your heating ticking over you build up a certain temperature in the house it's just ticking over to maintain that temperature all very well but it won't actually save you money if that's the way you want to live if you prefer your house to be at that nice even temperature and there is a difference between temperature and thermal comfort we've got to remember that thermal comfort is really dependent upon whether you've got cold walls radiating off if you live in a big old castle or something like that you've got big stone walls those walls will take weeks to heat up and they will also take weeks to cool down so when you go away on holiday in the winter and you come back and the house is cold because you've had the heating on it won't heat up immediately it may be a day or two before you feel really comfortable in that house and it's reached that heat so all the time we've got this thing of the house soaking up the heat working as a thermal store and letting that heat up radiating that heat out from the walls and the floor and everything else even the furniture to some extent will radiate the heat back so you're warming the fabric of the house now when you get a modern house a modern timber frame house where there is no real thermal mass we're talking about plasterboard timber insulation in the walls there's nothing really soaking that heat up in the same way that the old masonry structures soaked it up there is a very different feel to the house it heats up very very quickly because basically you're just heating up the air temperature but also you notice that it doesn't hold the heat particularly well once that heat is gone there is no thermal mass you walk into that house after a few days away and it feels cold you switch the heating on it heats up very very quickly but it will also lose the heat very quickly if you open the doors and the windows and therein lies another factor of course because not only have you got insulation but if you start opening windows if you start opening doors every time you open a door you're losing heat so it's impossible to calculate these things perfectly because we don't know how many times somebody's going in and out of the house so all these factors as i say come into play so if you prefer a house that's at a constant temperature then you can leave your heat ticking over and if that's the way you like it be prepared for the fact that the bills will be higher how much higher nobody knows because it really depends on what your thermal comfort levels are you may find that because the house is at an even temperature and as you walk around it there are no cold spots that you can actually lower the temperature on the thermostat from what you would normally have it now the way that gas boilers work in these days we've got condensing high efficiency gas boilers which work better at lower temperatures so the argument goes that if you turn that gas boiler right down to say 50 degrees and you have it ticking over then you just get that nice buildup of heat and if your insulation is reasonable you don't really need to have the radio that's operating at any more than 50 degrees centigrade to keep the house warm and that is undoubtedly a true statement but as i say all the time you're putting heat into a house you're paying for it so if you wake up in the morning you've got a gas boiler for example you switch the gas boiler on a timer for an hour before you wake up and the house is totally warm by the time you wake up and you switch it off at eight o'clock and maybe you're leaving the house at half bar state so it's already beginning to cool down before you leave and that way you don't have the heating coming on until say 4 30 in the afternoon just before you get home and all the heat losses from that house during the day as it's cooled off and cooled off are put back by that sudden vigorous action of the boiler because the boiler is operating a lot of the time at a higher temperature say 70 degrees centigrade it will put that heat back into the house a lot faster than something like a heat pump which is operating at a lower temperature so you see what i'm saying it's a different thing if you've got a heat pump for example and you've got to keep that heat pump on for 24 7 because if you turn it off because it works at those lower temperatures it will take several days to heat that house back up to temperature but if you've got a boiler a boiler working at those higher room temperatures will heat the house up in a lot shorter time so you get this cycle of heating the house up when you need it letting the house cool down naturally when you don't need it and of course that won't happen it won't happen to such an extent unless your insulation is terrible it won't happen to such an extent that the house will be freezing cold when you come back at 4 30 in the afternoon supposing you've got the second you came home early or something like that you think blimey house is cold but it wouldn't be that cold because it's been heated in the morning and it's losing its temperature throughout the day now in this room i've got underfloor heating and the honda floor heating works with a setback temperature and they say that as it gets too low the thermostat comes into place hello roger say again sorry are you the homeowner at the property yes is your loft still a normal loft space or have you converted it into a room or a bedroom it's a bedroom can you repeat that please it is a bedroom the room is a bedroom the loft is a bedroom okay no worries well thank you have a nice day and that's it is it okay thank you very much okay bye that was completely unstaged that just happened to be somebody cold calling me i'd love to know what they were selling but the last i never will but maybe you'll tell me maybe you've had these guys phoning you and you can say what's going on but you see what's happening all the time people are trying to sell you all kinds of stuff and i was talking about underfloor heating having this setback temperature if it drops too low during the night or something like that the boiler will come on and it will just tickle that heat back up so it will keep it at a level that means that it hasn't got to work too hard in the morning to get it up to temperature i'm standing on this heated floor and this heated floor has only been heated for about an hour and a half this morning but it is still giving out heat it's still got a lot of heat in it and it will come back on at half past four in the afternoon it will put a little bit more heat into it and we've never experienced the problem where this room is cold or that underfloor heating hasn't been doing its job so we don't set that setback temperature we just have this thing coming on and off as we require it and it works with the timer in the house that runs the rest of the central heating and it works perfectly well so it's because this underfloor heating is set in a screed which has a thermal mass that it soaks up the heat it keeps the heat and it radiates that heat out all day long just to keep this room warm now the other thing i would say about this argument about whether you keep the heating on or turning off we get such variations in temperature on these islands this island doesn't really have its own weather in the way that somewhere in a land mass somewhere like poland for example which has got a big land mess around it would have weather when it gets cold it tends to stay cold for quite a long time when it gets hot it gets very hot and it stays hot for a long time our temperatures can vary enormously so the wind changes direction blows in from the atlantic suddenly we've got mild wet weather it changes direction again it blows down from the north and suddenly we've got crisp cold dry weather freezing cold winds so having this house that you heat up 24 7 means that your house could actually end up too hot on certain days you know in the spring and the autumn when it varies quite a lot you may say you know what i really didn't need to have that heating on 24 7. i could have just switched it on for an hour or so just to take the chill off the air and we would have been happy so what i'm saying is that having a gas boiler or some kind of direct electric heating does give you that ability to chop and change as the weather changes so i remember when i had my first flat and it had night store radiators which worked on what they called economy 7 which was supposed to be a cheap rate electricity never was by the way when you woke up in the morning it was almost sweltering and of course when you got home in the evening it wasn't warm enough and you had to put that boost on to give it a bit more heat and again i remember staying in a swiss chalet when we were skiing and that had all this underfloor heating throughout had underfloor heating in the bedrooms it was just absolutely unbearable for us and we had to go around and open the windows if you're used to that level of heat and you want that heat all the time be prepared to pay for it if you're like me and you're a little bit more used to the cold temperatures and you're willing to put up with them then switching your heat on in the morning and off when you go to work and on again in the evening for a few hours is absolutely the best thing to do and that is one of my arguments when people come to sell you a heat pump they have to tell you that you need to have this thing on 24 7 and there's no argument with that by the way some people say no you don't but actually you do all the manufacturers will tell you do not switch this heat pump off because if you switch this heat pump off it will take several days for it to get back up to temperature and it will be using its backup auxiliary heater in order to do that so that it can keep pace again i'll just reiterate that the principle here is that you are putting heat into the house as fast as you are losing it in order to keep pace that's the principle of it if you stop losing the heat you won't have to heat your house as much and if you insulate yourself rather than your house then you'll find that this body which was designed by god allegedly is perfectly capable of keeping most people warm obviously when you get elderly like me and you get a little bit infirm then you might need a little bit of a boost you might need some extra heat but just keep exercising just keep moving around just keep eating just keep drinking and you'll be fine so we know that fuel prices are going up and uh if it's a hard winter we know that there's a lot of people who won't be able to afford to pay those bills so i hope that answered that question for you and there are plenty of other heating related videos on skill builder just go to our home page click the playlist or put in the search bar heating and you'll come up with all our other videos on heating i'm roger bisbee thanks very much for watching

Channel: Skill Builder

Views: 253,307

Keywords: life hacks, central heating, save money, central heating heatwave, central heating systems explained

Id: KxHcu7JvZwk

Length: 14min 23sec (863 seconds)

Published: Wed Jan 19 2022