I think our house is shockingly badly insulated.

[Danm54]

Well you need to know the height of the room as well. Or do as above just use a thermometer.

If you really want to work it out then you can do a calculation to work out it out exactly, using the specific heat capacity of air (fixed pressure though) ~1.006 kJ/kgC, and then you need the mass of the air density at 15c, so ~1.225 kg/m^3, then do your density x volume calculation, and use that to work out the energy needed which is 1.006 x (density/volume) x5, the 5 being the differential you want to calculate. You've get you answer in kJ, so if it was a 5x3x2 room 30m^3 then it would be 1.006 x 30 x 5.

You then need to work out the output of the radiator.

If you're just checking the rads are big enough then it isn't that complicated.
Find a heat loss calculator online, City Plumbing have a good one, put in your room sizes, construction, window area etc and it'll give you a btu and Kw figure that your rad should meet.

Little trickier finding the exact output of the rads as each manufacturer will have slightly different ways to work it out but find the same size rad on Screwfix or somewhere and the figures they give will be close enough.

As the op is finding out though, trvs aren't great at giving or maintaining accurate temps.

 

[Semple]

We recently replaced the ones in our living room for thermal lined full length curtains and put a draught excluder thing by the front door. Amazing what difference these make to how warm the room and hallway feel.

Definitely, i even tuck the living room curtains behind the radiator. I accept that we're all a bit limited in our homes with where you can put a window and a radiator, so naturally they're put together. But this never makes any sense as the coldest part of the room will be the window, so you're just warming the cold area. I accept by having curtains you will create a pocket of cold air, but at least the radiator is then used to warm the room.

In which case how much are these trvs worth?

The point of smart TRV's was to allow automatic changing of radiator settings depending on your usage.

(When i get round to buying/installing them) my idea would be to control based on room occupancy. I.e. during the day whilst in working in the office, it makes no sense to have the living room TRV's at max. Then in the evening whilst we're in the living room watching TV, there's no point the TRV in my office being at max.

I could change them manually throughout the day, for every day. But that gets tiring and tedious, especially as some radiators have covers on them, and my desk is in front of the one in the office.

 

[413x]

FWIW, ours is new build end terrace. Built in 2013. The Google nest is fitted in the hallway.
We went to Scotland over new year, so set the nest to "Away Mode" Heating only comes on if temp hits 10 degrees or lower.
House was 21 degrees when we left, and never dropped below 16 degrees for the 6 days we were away.
The Nest also provides info on how long it will take to get to temperature. Now its been in a while, its pretty accurate.
I have the boiler on ECO mode, and going from 20 to 22 degrees can take 1-2 hours at this time of year.

Radiators under windows is standard practice, as it helps the air circulate (Allegedly)

Hearing this I do believe this house has significant issues. I was also away at Christmas and heating was always coming on to keep it above 13(at the trv)

 

[413x]

Definitely, i even tuck the living room curtains behind the radiator. I accept that we're all a bit limited in our homes with where you can put a window and a radiator, so naturally they're put together. But this never makes any sense as the coldest part of the room will be the window, so you're just warming the cold area. I accept by having curtains you will create a pocket of cold air, but at least the radiator is then used to warm the room.



The point of smart TRV's was to allow automatic changing of radiator settings depending on your usage.

(When i get round to buying/installing them) my idea would be to control based on room occupancy. I.e. during the day whilst in working in the office, it makes no sense to have the living room TRV's at max. Then in the evening whilst we're in the living room watching TV, there's no point the TRV in my office being at max.

I could change them manually throughout the day, for every day. But that gets tiring and tedious, especially as some radiators have covers on them, and my desk is in front of the one in the office.

This is what I was doing. But gf has been complaining about temperature drop. This is where I'm at. I didn't find it too bad. But looking online I found our curves were very very different to others.

 

[sovietspybob]

I have to say i'm not a huge believer in smart TRV's in a lot of rooms, sure you don't want your spare bedroom heated when no one is in it but for a lounge you don't heat it in the day but then it takes far more energy to bring the room up to temp in the evening when you do want to use it.

I'd be interest to see proper calcs of keeping the whole house at a fairly steady temp rather than trying to spot heat individual rooms.

We've only got dumb TRV's and the only 2 i have on anything other than max are the en suite and downstairs toilet as they get way too hot otherwise. For the rest of the time the heating just comes on with doors open in the rooms so the whole house just gets to a nice comfortable temp until the thermostat in the hall turns the whole heating system off.

 

[413x]

I have to say i'm not a huge believer in smart TRV's in a lot of rooms, sure you don't want your spare bedroom heated when no one is in it but for a lounge you don't heat it in the day but then it takes far more energy to bring the room up to temp in the evening when you do want to use it.

I'd be interest to see proper calcs of keeping the whole house at a fairly steady temp rather than trying to spot heat individual rooms.

We've only got dumb TRV's and the only 2 i have on anything other than max are the en suite and downstairs toilet as they get way too hot otherwise. For the rest of the time the heating just comes on with doors open in the rooms so the whole house just gets to a nice comfortable temp until the thermostat in the hall turns the whole heating system off.

Starting to think the same.
Originally I thought this is great. We work in office during day and then go in other rooms in evening. Heat office and kitchen. Then before work finishes heat the living room etc.

But now I'm wondering if it is better to revert to dumb rads. But this window issue. Will try and research if there's any way to 'close the dafts'.
I think this is the biggest issue for myself

 

[krooton]

Something deffo aint right.

I have Tado, and the largest and draftiest room is the lounge, which has a cat flap that does a great job of letting in drafts.

Massive french doors, plus a big bay window area, with all the vent closed, and it still takes 12 hours for the temp to drop from 20 to 12.

That said, the only rad we have that is directly under a window is in the downstairs toilet.

 

[Countcussy]

Starting to think the same.
Originally I thought this is great. We work in office during day and then go in other rooms in evening. Heat office and kitchen. Then before work finishes heat the living room etc.

But now I'm wondering if it is better to revert to dumb rads. But this window issue. Will try and research if there's any way to 'close the drafts'.
I think this is the biggest issue for myself

One of the first things I did when we moved in was address the window vents. Cheap plastic things that were useless. When open, they not only let air in, but a huge amount of external noise.
Removed vents, stuffed the holes with some pond filter foam I had lying around, and re-fitted the vents to make it look tidy. Made a huge difference. When I had some rear windows changed, it became my choice whether I wanted vents or not.
I am aware vents are part of the Regs and necessary for "fresh" air. But, we have 3 toilet extractors and the kitchen extractor all plumbed to the outside, which all let air in/out.
And if we want fresh air, we open a window or go outside.
Downstairs is open plan kitchen/living room, so those TRVs are on max, 2 rads have no TRV at all,(To keep boiler happy at low demand) and rest are set mid to low, especially upstairs.
The heat travelling upstairs is the biggest problem for us. Getting child/wife to close doors saves me more money than any other tech

 

[SoliD]

Starting to think the same.
Originally I thought this is great. We work in office during day and then go in other rooms in evening. Heat office and kitchen. Then before work finishes heat the living room etc.

But now I'm wondering if it is better to revert to dumb rads. But this window issue. Will try and research if there's any way to 'close the dafts'.
I think this is the biggest issue for myself

Simple way would be to remove any sealant around the frame and redo it.

Our house is pretty bad as it's tile faced on first floor, so single skin brick - bit of felt and then layer of tiles, but even overnight it'll only drop 3 or 4c at most in an empty room. Planning to resolve this year by installing internal celotex insulation and moisture barriers etc. We have had 2 new windows in front South facing bedrooms and the rooms have felt a lot better this year moving from old metal framed double glazing.

 

[413x]

Something deffo aint right.

I have Tado, and the largest and draftiest room is the lounge, which has a cat flap that does a great job of letting in drafts.

Massive french doors, plus a big bay window area, with all the vent closed, and it still takes 12 hours for the temp to drop from 20 to 12.

Yep. I agree
This is the room stat on the kitchen table.
The radiator at trv has been set to 22c since 9am.
I can absolutely feel the gradient across the room.
You can see ita not getting above 15c really



Added the kitchen trv stat.



I'm at a bit of a loss. The epc rating wasn't this bad I'm sure. Going to dig it out

If I'm looking at this correctly. In this room I'd have to have the tado permanently open basically to hit 20c across the room?? This isn't right.

 

[krooton]

Well you also have to factor in that the TRV can only read the temperature from it's surrounding, unless you have it controlled by a separate thermostat elsewhere.

So if you have one of those radiator box covers, the TRV will get up to its target temp quickly, whilst the actual general temperature in the room will not match.

Not so much of a problem for uncovered TRVs as they are close to the ground, so by the time that level is reading 20º, the rest of the room should be decently warm. The higher your ceilings, the longer that will take to happen.

 

[Semple]

Starting to think the same.
Originally I thought this is great. We work in office during day and then go in other rooms in evening. Heat office and kitchen. Then before work finishes heat the living room etc.

But now I'm wondering if it is better to revert to dumb rads. But this window issue. Will try and research if there's any way to 'close the dafts'.
I think this is the biggest issue for myself

I suspect it's your windows that are the main culprit. Especially if you can feel a draft when near, that's not normal, you shouldn't feel a draft near the windows at all.

 

[413x]

I suspect it's your windows that are the main culprit. Especially if you can feel a draft when near, that's not normal, you shouldn't feel a draft near the windows at all.

Yes definitely a draft coming from between the seal where the frame meets the opening part.
(bad terminology)
I can actually feel air flow.

I've been looking online and some say you can replace the hinge. My weekend job is going to be going round all my windows and checking. And checking in with neighbours.

I'm. Guessing this is further compounded by not having good curtains/shutters etc and rad being under said drafty window

Can't really justify new windows if might only be going through next winter here.

 

[Countcussy]

Yes definitely a draft coming from between the seal where the frame meets the opening part.
(bad terminology)
I can actually feel air flow.

I've been looking online and some say you can replace the hinge. My weekend job is going to be going round all my windows and checking. And checking in with neighbours.

I'm. Guessing this is further compounded by not having good curtains/shutters etc and rad being under said drafty window

On some, you can adjust the hinge. You could also consider replacing the gaskets/rubbers if they have them? Its a cheap simple fix, and worked wonders at my previous property.

 

[413x]

On some, you can adjust the hinge. You could also consider replacing the gaskets/rubbers if they have them? Its a cheap simple fix, and worked wonders at my previous property.

I'll get a pic

 

[Semple]

Yes definitely a draft coming from between the seal where the frame meets the opening part.
(bad terminology)
I can actually feel air flow.

I've been looking online and some say you can replace the hinge. My weekend job is going to be going round all my windows and checking. And checking in with neighbours.

I'm. Guessing this is further compounded by not having good curtains/shutters etc and rad being under said drafty window

Can't really justify new windows if might only be going through next winter here.

If you light a candle and stick it in the window, once you've stopped moving it should settle almost completely still. If it's flickering around a lot then there's drafts.

Yeah if you're only planning on living there for another year then there's unlikely to be any ROI. If you were looking for at least the next 4-5 then it may well be worth doing if they're approaching 25 years old. You'd also need to consider the next prospective buyer might knock down the price a little if the windows look like they need replacing.

 

[413x]

Here's the hinge mechanism


And in this poor pic you can see the gap.



Edit
All windows in house open with hinge on size with full height open.

 

[413x]

If you light a candle and stick it in the window, once you've stopped moving it should settle almost completely still. If it's flickering around a lot then there's drafts.

Yeah if you're only planning on living there for another year then there's unlikely to be any ROI. If you were looking for at least the next 4-5 then it may well be worth doing if they're approaching 25 years old. You'd also need to consider the next prospective buyer might knock down the price a little if the windows look like they need replacing.

Yeah definitely not. 5 years. Probably 2 years tops.

 

[Countcussy]

Hinges are maybe a little worn, vac the rubbish out of the channel whilst you are at it.

When you open and close the window handle with the windows open, you will see some small circular items move. These are normally cams with a Hex head, and are in the middle, or at either end of the window.
On some windows, you can turn these to increase or decrease the amount of "pull" the window has when closing.

Another option is the seals. The rubber seals just pull out (With a little persuasion). You will then know the "profile" of the seal.
Search on line or a local window fitter. You can get oversize versions for exactly this kind of scenario. Purchase by the meter, so you could do one window and test.
Also do a seal test. Get a thin piece of paper/card With the window closed, try to push the paper between window and gasket.
You should feel a little resistance and paper should stay in its own, due to the pressure of the gasket.

I feel you pain, and it reminded me of another issue we had when we first moved in. The patio doors on the back were so draughty, the curtains would move. Purely because the builders could not be bothered to adjust the doors properly.

 

[413x]

Hinges are maybe a little worn, vac the rubbish out of the channel whilst you are at it.

When you open and close the window handle with the windows open, you will see some small circular items move. These are normally cams with a Hex head, and are in the middle, or at either end of the window.
On some windows, you can turn these to increase or decrease the amount of "pull" the window has when closing.

Another option is the seals. The rubber seals just pull out (With a little persuasion). You will then know the "profile" of the seal.
Search on line or a local window fitter. You can get oversize versions for exactly this kind of scenario. Purchase by the meter, so you could do one window and test.
Also do a seal test. Get a thin piece of paper/card With the window closed, try to push the paper between window and gasket.
You should feel a little resistance and paper should stay in its own, due to the pressure of the gasket.

I feel you pain, and it reminded me of another issue we had when we first moved in. The patio doors on the back were so draughty, the curtains would move. Purely because the builders could not be bothered to adjust the doors properly.

Thanks for this. I've found one other window with this issue so far and this has me thinking this is the main problem.

I have 2 upstairs spare bedrooms rooms on the left of the house. One is small and a study and other is a guest room/partners study.

The big room (set to same temp at trv as the small) occupies a significantly smaller time portion "on" than the small room.
But the small has the same seal issue and the bigger room doesn't.

Hopefully this is the main issue and can be fixed with what you mentioned above.