Windows like that were popular in the late 60's/early 70's. Our last house had them. Most of the houses had the lower sections boarded up and stuffed with a bit of insulation. When I redid the cladding a few years ago, i stripped it back and fitted 100mm PIR before laying new composite cladding over the top. Made a good difference to those rooms 👍
15 years ago I fitted a roll-out sunshade over our south-facing patio doors, and it made a huge difference to the over-heating in the summer. Interestingly it only needs to be unrolled about 3 foot to shade the whole door because the sun is so high in the sky in summer. It's getting rather tatty now and I'm wondering if I can replace it with a solar panel. I agree about the polythene secondary glazing, it's only a cheap, temporary solution. Now we have clear solid plastic sheets from Magneglaze. It's almost invisible and easy to remove if you want to open a window. The other product I like is 'double cellular blinds'. The thermal camera makes the (40 year old) patio doors look as warm as the walls when the blind is down.
As it happens an awning for our patio doors is something we're planning for this year. It's West facing so will need to be quite deep but should help a lot in the Summer. I did try suggesting those thermal blinds to Kat a while back but she wasn't keen. Might try again at some point!
It's certainly a good double check, I agree. I expect a Heat Geek engineer could do a better heat calculation than me, but I'm glad this tool exists so I can say least try this sort of stuff out for myself.
Hi Tim. I think a U value of 1,6 for triple glazing is quite high. I replaced my windows, from double to triple. Before that, i had a company measuring the heat loss of each element: for Upvc double it was 1,2, and for the triple (top of the line), was
You're not the first to point this out. I guess HeatPunk is erring on the side of caution, but regardless it's good to know that modern triple glazing is so good.
Interesting experiment. I’m a bit surprised that the builders didn’t have to fit triple glazed as standard to get through building regulations for heat loss with such large panes - but if they’re not mandated then they’ll put in the least they can as solar gain and heat loss are not their problems down the road.
Well, quite, I'm surprised with a lot of things about this house, given how new it is, for example no PV built in and gas heating instead of heat pump. But at least that gave me the opportunity to do it myself! Although the windows might take a lot longer to address than the other stuff.
I’m a little surprised by the u-values you are using for the glass. Four years ago, I replaced my 30 years old double pane windows by triple pane (warm edge) windows with a u-value of 0.5 W/m2K. These were Krypton filled windows, that had a price of around € 115,- /m2 for a total of 16 windows. And the total was also about 16 m2. I replaced the windows as diy job and adapted the wooden window frames for the larger thickness of the glass.
The u values are just what Heatpunk had set for the materials, I didn't pick them. I guess they're erring on the side of caution. Good to know you can get significantly better windows than that though.
Hi Tim, You could get secondary glazing. I used to have that in conjunction with single glazed windows in my old place to effectively make double glazed windows. They are safety glass in an aluminum frame with panels that slide sideways. That's if you don't like the cling film solution. For the summer you could add shutters outside. They are more popular on the continent and the advantage is they keep the heat in the outside.
Thanks for very useful information. Have you considered insulated shutter rollers? They're remarkably useful and effective, you can automate them to close when it gets dark and open in the morning. They can come with a key fob remote control. They cut down draft, sound/noise, heat loss and obviously light
We already have roller blinds on most windows which are pretty good but not insulated. The curtains are insulated though, so those already do a good job of mitigating some of the heat loss. I'm considering insulated blinds for the bifolds, however, as those are the only panels without blinds yet.
Interesting video, it was nice to see how things were modelled in heatpunk. I did a video a while back modelling windows as if they were solar panels to try and forecast the solar gain through them - feel free to take a look / model your windows with it. It would be interesting to see how much heat you gain on a given day through those large windows overlooking your local landscape.
The glazing units themselves can make a massive difference. We replaced our relatively new (2018) patio doors with new, sliding doors but with triple glazing with a reflective coating. Even though there is more glass, the room is warmer in the cold and cooler when in direct sunshine. It’s not a small commitment, but high quality glazing will make a big difference.
@@TimAndKatsGreenWalk of course. With the amount of glass in your house, it’s a massive commitment. On a positive note, with your A2A system, at least you have total solar powered air conditioning when you need it most!
Yes, take a look at my September stats video, I show how much cooling we used over the Summer in that one. Not super loads, it has to be said, as we made strategic use of the blinds to help keep the house from overheating too much.
I got a triple for double deal on expensive triple glazing (expensive in terms of U value: 0.67). This to replace leaky double glazed patio doors (that covered the whole width of the back of my downstairs) with big lift and slide doors. Seems to have reduced heat loss so far. Will see next winter.
An interesting investigation Tim, thanks for the video. It certainly might be a factor when coming to replace the windows perhaps. For us, blinds have been a useful addition. Of course on the continent they use blinds built into the window frames (Germany) and France traditionally use shutters on the outside.
I really like the idea of blinds built into the windows themselves. It'll be a long time before we replace these windows but I'll definitely be looking into all the available options when I do.
Hi Tim, have you considered putting reflective film on the windows (professionally or DIY) not sure how it would change your calculations with heat loss, but it does help in the summer to reduce heat coming in, and also anyone outside can not see in, so you don’t need to pull curtains as much 👍😎
That might be something I look into but one thing we definitely have planned is an awning over the patio doors. That'll help for sure with the biggest source of heat in the Summer.
A lot of these things are fine in principle but less so in practice. We had triple glazing in our last house, and very large picture windows and I would NOT rush to have them again. All glazing units have a lifetime : sooner or later the seals will break down , especially if the units are exposed to a lot of sunlight. Triple glazed units have twice as many seals as double glazed units and they weight 50% more. Large picture windows, in particular, are very heavy and, if not properly supported in the frames, the risk of premature seal failure becomes even higher. I do agree that there is a tendency for a higher solar gain - that said, we had argon fill, low E and A rated frames and the house still baked in the summer! Large windows have the advantage of loads of light and we notice that now with our old house and smaller double glazed windows (argon fill, Low E). Triple glazing is more marketing than actual actual improvement. The units cost minimally more to make wholesale but can be upsold to seduce customers. Almost any technically minded glazing salesman knows this. If people are considering retrofitting triple glazing units think carefully first : the glazing unit depth for an optimal argon fill low E needs to be in the region of 36mm. Most double glazing unit depths do not exceed 28 and if triple glazing is retrofitted, the optimal pane gap is not achieved. How do I know this stuff ? I used to own a glazing repair company !
Well, as with all these things it's the details that matter, i.e. the u values. Regardless of the number of sheets a lower u values will let less heat out. If you can get a high quality double glazed unit with the same u value as a triple glazed unit then clearly that double glazed unit would be preferred. Regardless, I'm not changing any of the windows any time soon.
As a general contractor for over 33 years I always tell my customers to get the best windows they can afford. There are hundreds of window manufacturers and designs. In the US, efficiency levels range from U.50 to U.10. For new construction code starts around U.32. It does not cost a huge amount to upgrade to U.20. To go higher starts to get pricy. FYI, U.10 windows are available either as triple glazed or dual glazed with films and coatings.
Yes, indeed. As and when we eventually replace these windows (who knows when that will be) I'll definitely be looking for the best option we can afford at the time.
my next task is actually replacing all uPVC windows myself, did lots of reviews and shows, you shall check out brands such as Infernorm, Gaulhofer, Norsken…you want Alu-Timber combo (alu exterior, timber interior), tripple glazed and solar control glass, these get you u values around 0.7-0.8, ie passive house specs…wont be cheap but you need to do it only once 👍
@@TimAndKatsGreenWalk forgot to mention, if you really keen getting your house more energy efficient, one can get passive house retrofit certified through EnerPHit, worth researching 👍
Tim , Metal frame thermal bridging causes a lot of heatloss . Try run your simulation with existing windows double glazed but wood/upvc... I guess it will be somewhere in the middle or nearer to triple ?
Our frames have thermal breaks but even so they do lose a lot of heat. But replacing the frames is the most expensive bit so that's why it's not happening any time soon.
I think your curtains will be as effective as triple glazing - measure the temperature between the curtains . May be add translucent thermal blinds as well.
@@TimAndKatsGreenWalk the problem with triple glazing is that there is twice the chance of a window blowing. We have a similar wall of glass and two double glazed panels blown in 12 years - £800 is a lot of heating cost to recover and more for triple.
The cling film pseudo triple glazing can be done really neatly. People rarely notice that I've done it to my windows. Definitely reduces condensation, but other than that I have no idea how much difference it actually makes.
@@TimAndKatsGreenWalk It's a cheap and easy experiment. Voice of experience: When you're attaching the film to the double sided tape, your main priority is to avoid ripples where it sticks to the tape. The hair drier will stretch it tight, but can't take the ripples out. Don't worry too much because the hair drier fixes most imperfections.
That is a lot of glass. I work in the Middle East and recently wrote a Paper on IR Solar gain through glass and its destructive nature. Whilst replacing glazing with Solar glass is expensive, Professionally installed window film (can be clear and you won’t see it) makes a big difference by blocking / reflecting solar IR/UV back out so saves your skin too.
Have you considered smart motors on the curtains and blinds for example switchboard? We are about to do this with both blinds and curtains. The greatest heat loss happens when the difference of temperature is largest and we are not home to pull the curtains.
What still baffles me to this day is why double or triple glazed windows are not more common here in Australia. Surely by now they would be more common as another way to keep houses cooler during our very hot summers.
What about the old aluminium vs UPVC windows? This is my next upgrade after getting the heat pump (which isn't quite working), the solar pv to help with the huge ASHP power demand.
We have modern aluminum frames but they're still not as good as upvc, so I'd like to get rid of them eventually. But that would be far too expensive to justify. I'm not going to compare every material against every other though, that would take forever. You have access to HeatPunk if you wanted to do it yourself, of course.
You live in a cool climate, so heat loss is your major cost. The best thing is there would be better insulation, but, solar reflection does indeed help as well in the summer. You might consider solar films that reflect as much sunlight as possible to reduce your heat gain during the summer. The best energy saving for you, though, would be to install temporary insulation panels over your windows during the colder months (Dec-Mar). I live in a very hot & humid climate (Houston TX), so cooling to offset heat gain is a major cost here. For my situation, white reflective roof material & solar window reflective film & good insulation is best.
It'd be a shame to reduce the amount of light coming into the house in Winter though by blocking the windows off. It gets pretty dark in the UK over the Winter months! And we have a cracking view I'd not want to sacrifice 😉
@@TimAndKatsGreenWalk My grandparents lived in the south of France. You weren't allowed either light or air into the house in the middle of the day. They had tiny windows in a house with thick walls. That house was never really hot.
@@jchidley we attempt to do that when it's super hot by closing the blinds and curtains on the sunny side of the house. It helps, but not completely. At least we have the AC if required.
@@TimAndKatsGreenWalk In hot countries, they have shutters on the outside to keep the sun out. Curtains and blinds on the inside get hot in the sun and then the glass keeps the heat in :-(. This is why I am also looking at AC
@@TimAndKatsGreenWalk, I forgot to add. I'm replacing my window, which is 3.5 by 2m, glazing for £1.5K, and it cuts the heat loss by half without going to triple glazing. It is worth checking the double glazing units because if they are builder grade, they will have u value of 1.6 or more depending on the year it was installed. High-quality double glazing can have a U value of 1.1. Your windows are big enough for the frame not to influence the insulation performance of the overall window
@@codeforme8860 fair enough. For the purposes of this video it was more the relative difference between big and small windows that I was trying to demonstrate, rather than worrying too much about the absolute u values. But interesting to know you can get better double glazed units.
@@TimAndKatsGreenWalk the funny thing is small windows are actually worse for energy performance especially if you have metal frames. I’d be happy to talk you through identifying the glazing you have and calculating the exact heat loss. Just Incase you didn’t know, the glazing and frames are different. The glazing is changeable there is some contrast depending on the frames. If you have aluminium window frames it never makes sense to change the frame. Just for context changing the frame for my floor to ceiling window would cost £10k. The frame it self would last 100 years
@@codeforme8860 we're not really in a position to change any glazing at this point but thanks for the offer. I absolutely hate our current window frames, they create condensation at the bottom when it gets cold outside even though they have a thermal break, which is a real pain. I'd love to get rid of them at some point but as you say, it's jolly expensive.
![CHILE vs. BRASIL [1-2] | RESUMEN | ELIMINATORIAS SUDAMERICANAS | FECHA 9](http://i.ytimg.com/vi/5ObJt_71AYc/mqdefault.jpg)
Windows like that were popular in the late 60's/early 70's. Our last house had them. Most of the houses had the lower sections boarded up and stuffed with a bit of insulation.
When I redid the cladding a few years ago, i stripped it back and fitted 100mm PIR before laying new composite cladding over the top.
Made a good difference to those rooms 👍
I'm not going to cover up any of the windows though.
15 years ago I fitted a roll-out sunshade over our south-facing patio doors, and it made a huge difference to the over-heating in the summer. Interestingly it only needs to be unrolled about 3 foot to shade the whole door because the sun is so high in the sky in summer. It's getting rather tatty now and I'm wondering if I can replace it with a solar panel.
I agree about the polythene secondary glazing, it's only a cheap, temporary solution. Now we have clear solid plastic sheets from Magneglaze. It's almost invisible and easy to remove if you want to open a window.
The other product I like is 'double cellular blinds'. The thermal camera makes the (40 year old) patio doors look as warm as the walls when the blind is down.
As it happens an awning for our patio doors is something we're planning for this year. It's West facing so will need to be quite deep but should help a lot in the Summer.
I did try suggesting those thermal blinds to Kat a while back but she wasn't keen. Might try again at some point!
Heatpunk is fantastic, absolutely love it really useful for gauging whether a heating engineer knows what they're talking about or not!
It's certainly a good double check, I agree. I expect a Heat Geek engineer could do a better heat calculation than me, but I'm glad this tool exists so I can say least try this sort of stuff out for myself.
Hi Tim. I think a U value of 1,6 for triple glazing is quite high. I replaced my windows, from double to triple. Before that, i had a company measuring the heat loss of each element: for Upvc double it was 1,2, and for the triple (top of the line), was
You're not the first to point this out. I guess HeatPunk is erring on the side of caution, but regardless it's good to know that modern triple glazing is so good.
Interesting experiment. I’m a bit surprised that the builders didn’t have to fit triple glazed as standard to get through building regulations for heat loss with such large panes - but if they’re not mandated then they’ll put in the least they can as solar gain and heat loss are not their problems down the road.
Well, quite, I'm surprised with a lot of things about this house, given how new it is, for example no PV built in and gas heating instead of heat pump. But at least that gave me the opportunity to do it myself! Although the windows might take a lot longer to address than the other stuff.
I’m a little surprised by the u-values you are using for the glass. Four years ago, I replaced my 30 years old double pane windows by triple pane (warm edge) windows with a u-value of 0.5 W/m2K. These were Krypton filled windows, that had a price of around € 115,- /m2 for a total of 16 windows. And the total was also about 16 m2. I replaced the windows as diy job and adapted the wooden window frames for the larger thickness of the glass.
The u values are just what Heatpunk had set for the materials, I didn't pick them. I guess they're erring on the side of caution. Good to know you can get significantly better windows than that though.
Hi Tim,
You could get secondary glazing. I used to have that in conjunction with single glazed windows in my old place to effectively make double glazed windows. They are safety glass in an aluminum frame with panels that slide sideways. That's if you don't like the cling film solution.
For the summer you could add shutters outside. They are more popular on the continent and the advantage is they keep the heat in the outside.
Definitely a possible option. Might not be worth the expense though. I'll look into it.
Thanks for very useful information. Have you considered insulated shutter rollers? They're remarkably useful and effective, you can automate them to close when it gets dark and open in the morning. They can come with a key fob remote control. They cut down draft, sound/noise, heat loss and obviously light
We already have roller blinds on most windows which are pretty good but not insulated. The curtains are insulated though, so those already do a good job of mitigating some of the heat loss. I'm considering insulated blinds for the bifolds, however, as those are the only panels without blinds yet.
Highly recommend reflective film on the windows in the summer. Makes a large difference to rhe heat build up.
A few folks have mentioned that. I'll look into it
Interesting video, it was nice to see how things were modelled in heatpunk. I did a video a while back modelling windows as if they were solar panels to try and forecast the solar gain through them - feel free to take a look / model your windows with it. It would be interesting to see how much heat you gain on a given day through those large windows overlooking your local landscape.
Yeah, you can definitely tell we need way less heating as soon as the sun comes out. At this time of year it makes a big difference for sure.
The glazing units themselves can make a massive difference. We replaced our relatively new (2018) patio doors with new, sliding doors but with triple glazing with a reflective coating. Even though there is more glass, the room is warmer in the cold and cooler when in direct sunshine. It’s not a small commitment, but high quality glazing will make a big difference.
Yes, indeed, it's just not something we're prepared to do in the near term. One day maybe.
@@TimAndKatsGreenWalk of course. With the amount of glass in your house, it’s a massive commitment. On a positive note, with your A2A system, at least you have total solar powered air conditioning when you need it most!
@@twelvebears1971 yup, absolutely!
Thanks for the very interesting video, have you done any calculations on how much cooling you use in the summer?
Yes, take a look at my September stats video, I show how much cooling we used over the Summer in that one. Not super loads, it has to be said, as we made strategic use of the blinds to help keep the house from overheating too much.
I got a triple for double deal on expensive triple glazing (expensive in terms of U value: 0.67). This to replace leaky double glazed patio doors (that covered the whole width of the back of my downstairs) with big lift and slide doors. Seems to have reduced heat loss so far. Will see next winter.
That's good. It certainly sounds like it'll make a big difference, so I hope it works out that way next Winter.
An interesting investigation Tim, thanks for the video. It certainly might be a factor when coming to replace the windows perhaps. For us, blinds have been a useful addition. Of course on the continent they use blinds built into the window frames (Germany) and France traditionally use shutters on the outside.
I really like the idea of blinds built into the windows themselves. It'll be a long time before we replace these windows but I'll definitely be looking into all the available options when I do.
Hi Tim, have you considered putting reflective film on the windows (professionally or DIY) not sure how it would change your calculations with heat loss, but it does help in the summer to reduce heat coming in, and also anyone outside can not see in, so you don’t need to pull curtains as much 👍😎
That might be something I look into but one thing we definitely have planned is an awning over the patio doors. That'll help for sure with the biggest source of heat in the Summer.
Get the industrial strength reflective film ,it works so much better.
A lot of these things are fine in principle but less so in practice.
We had triple glazing in our last house, and very large picture windows and I would NOT rush to have them again. All glazing units have a lifetime : sooner or later the seals will break down , especially if the units are exposed to a lot of sunlight. Triple glazed units have twice as many seals as double glazed units and they weight 50% more. Large picture windows, in particular, are very heavy and, if not properly supported in the frames, the risk of premature seal failure becomes even higher.
I do agree that there is a tendency for a higher solar gain - that said, we had argon fill, low E and A rated frames and the house still baked in the summer!
Large windows have the advantage of loads of light and we notice that now with our old house and smaller double glazed windows (argon fill, Low E).
Triple glazing is more marketing than actual actual improvement. The units cost minimally more to make wholesale but can be upsold to seduce customers. Almost any technically minded glazing salesman knows this.
If people are considering retrofitting triple glazing units think carefully first : the glazing unit depth for an optimal argon fill low E needs to be in the region of 36mm. Most double glazing unit depths do not exceed 28 and if triple glazing is retrofitted, the optimal pane gap is not achieved.
How do I know this stuff ? I used to own a glazing repair company !
Well, as with all these things it's the details that matter, i.e. the u values. Regardless of the number of sheets a lower u values will let less heat out. If you can get a high quality double glazed unit with the same u value as a triple glazed unit then clearly that double glazed unit would be preferred. Regardless, I'm not changing any of the windows any time soon.
As a general contractor for over 33 years I always tell my customers to get the best windows they can afford. There are hundreds of window manufacturers and designs. In the US, efficiency levels range from U.50 to U.10. For new construction code starts around U.32. It does not cost a huge amount to upgrade to U.20. To go higher starts to get pricy.
FYI, U.10 windows are available either as triple glazed or dual glazed with films and coatings.
Yes, indeed. As and when we eventually replace these windows (who knows when that will be) I'll definitely be looking for the best option we can afford at the time.
my next task is actually replacing all uPVC windows myself, did lots of reviews and shows, you shall check out brands such as Infernorm, Gaulhofer, Norsken…you want Alu-Timber combo (alu exterior, timber interior), tripple glazed and solar control glass, these get you u values around 0.7-0.8, ie passive house specs…wont be cheap but you need to do it only once 👍
Nice, yeah, that'd be ideal. Something to aim for but realistically not something we're likely to achieve for many more years, however.
@@TimAndKatsGreenWalk forgot to mention, if you really keen getting your house more energy efficient, one can get passive house retrofit certified through EnerPHit, worth researching 👍
@@robert_minarik at it happens I have been looking into that very thing!
Tim , Metal frame thermal bridging causes a lot of heatloss . Try run your simulation with existing windows double glazed but wood/upvc... I guess it will be somewhere in the middle or nearer to triple ?
Our frames have thermal breaks but even so they do lose a lot of heat. But replacing the frames is the most expensive bit so that's why it's not happening any time soon.
I think your curtains will be as effective as triple glazing - measure the temperature between the curtains . May be add translucent thermal blinds as well.
But hear me out: triple glazing with curtains...
@@TimAndKatsGreenWalk the problem with triple glazing is that there is twice the chance of a window blowing. We have a similar wall of glass and two double glazed panels blown in 12 years - £800 is a lot of heating cost to recover and more for triple.
The cling film pseudo triple glazing can be done really neatly. People rarely notice that I've done it to my windows. Definitely reduces condensation, but other than that I have no idea how much difference it actually makes.
That's good to know. I'm tempted to do a trial on one window to see what I think.
@@TimAndKatsGreenWalk It's a cheap and easy experiment.
Voice of experience: When you're attaching the film to the double sided tape, your main priority is to avoid ripples where it sticks to the tape. The hair drier will stretch it tight, but can't take the ripples out. Don't worry too much because the hair drier fixes most imperfections.
That is a lot of glass. I work in the Middle East and recently wrote a Paper on IR Solar gain through glass and its destructive nature. Whilst replacing glazing with Solar glass is expensive, Professionally installed window film (can be clear and you won’t see it) makes a big difference by blocking / reflecting solar IR/UV back out so saves your skin too.
Yeah, I might look into that at some point. Definitely pros and cons to big windows!
Have you considered smart motors on the curtains and blinds for example switchboard? We are about to do this with both blinds and curtains. The greatest heat loss happens when the difference of temperature is largest and we are not home to pull the curtains.
Our blinds are all motorised and can be controlled remotely by an app on my phone.
What still baffles me to this day is why double or triple glazed windows are not more common here in Australia.
Surely by now they would be more common as another way to keep houses cooler during our very hot summers.
Yeah, that definitely sounds like it could help. Perhaps it will become more common over time.
What about the old aluminium vs UPVC windows? This is my next upgrade after getting the heat pump (which isn't quite working), the solar pv to help with the huge ASHP power demand.
We have modern aluminum frames but they're still not as good as upvc, so I'd like to get rid of them eventually. But that would be far too expensive to justify. I'm not going to compare every material against every other though, that would take forever. You have access to HeatPunk if you wanted to do it yourself, of course.
You live in a cool climate, so heat loss is your major cost. The best thing is there would be better insulation, but, solar reflection does indeed help as well in the summer. You might consider solar films that reflect as much sunlight as possible to reduce your heat gain during the summer. The best energy saving for you, though, would be to install temporary insulation panels over your windows during the colder months (Dec-Mar).
I live in a very hot & humid climate (Houston TX), so cooling to offset heat gain is a major cost here. For my situation, white reflective roof material & solar window reflective film & good insulation is best.
It'd be a shame to reduce the amount of light coming into the house in Winter though by blocking the windows off. It gets pretty dark in the UK over the Winter months! And we have a cracking view I'd not want to sacrifice 😉
What's the heat loss if you removed the windows altogether? Not realistic but would be good to see the ratio between walls and windows
Good question. I decided not to do that for this video, to keep it brief, but I might just try that out for fun.
Is that a saving of one kilowat per day?. . Diminishing returns Tim
I did say I wasn't planning on replacing any windows until the existing ones had reached the end of their useful life.
The windows should be good for another 30 years. If it ain't broke don't fix it
The savings equate to 1 kwHr for every hour the outside temperature is -2 degrees C.
@@iaack1070 thanks for the clarification
This is the reason why in hot and cold countries houses used to have small windows.
Yup, exactly!
@@TimAndKatsGreenWalk My grandparents lived in the south of France. You weren't allowed either light or air into the house in the middle of the day. They had tiny windows in a house with thick walls. That house was never really hot.
@@jchidley we attempt to do that when it's super hot by closing the blinds and curtains on the sunny side of the house. It helps, but not completely. At least we have the AC if required.
@@TimAndKatsGreenWalk In hot countries, they have shutters on the outside to keep the sun out. Curtains and blinds on the inside get hot in the sun and then the glass keeps the heat in :-(. This is why I am also looking at AC
I found the defult U values for the windows in heatpunk not that accurate
Ok
@@TimAndKatsGreenWalk, I forgot to add. I'm replacing my window, which is 3.5 by 2m, glazing for £1.5K, and it cuts the heat loss by half without going to triple glazing. It is worth checking the double glazing units because if they are builder grade, they will have u value of 1.6 or more depending on the year it was installed. High-quality double glazing can have a U value of 1.1. Your windows are big enough for the frame not to influence the insulation performance of the overall window
@@codeforme8860 fair enough. For the purposes of this video it was more the relative difference between big and small windows that I was trying to demonstrate, rather than worrying too much about the absolute u values. But interesting to know you can get better double glazed units.
@@TimAndKatsGreenWalk the funny thing is small windows are actually worse for energy performance especially if you have metal frames.
I’d be happy to talk you through identifying the glazing you have and calculating the exact heat loss.
Just Incase you didn’t know, the glazing and frames are different. The glazing is changeable there is some contrast depending on the frames.
If you have aluminium window frames it never makes sense to change the frame. Just for context changing the frame for my floor to ceiling window would cost £10k. The frame it self would last 100 years
@@codeforme8860 we're not really in a position to change any glazing at this point but thanks for the offer. I absolutely hate our current window frames, they create condensation at the bottom when it gets cold outside even though they have a thermal break, which is a real pain. I'd love to get rid of them at some point but as you say, it's jolly expensive.
If the sun is powering all your heating and cooling via solar, there is nothing to fix.
There is always room for improvement.