Insulation - where to start?
Discussion
One of the bedrooms in my late 1960s bungalow needs better insulation.
It’s on the north side of the building and has 3 outside walls.
It’s a twin wall brick construction with plastered thermalite blocks as the inner skin and a suspended wooden floor.
It currently has 250mm of loft insulation, 20 year old wooden
framed, double glazed windows and foam cavity wall insulation.
What’s the most cost effective way to improve things?
The room is big enough to consider over boarding the walls with
Kingspan or similar and drywalling over. I’m also considering reflooring and putting some insulation under there, but apparently it’s not as simple as I thought and you can’t just hang insulation between the joists.
Any pointers or suggestions would be welcome as I’m fed up with missus moaning about it being cold.
It’s on the north side of the building and has 3 outside walls.
It’s a twin wall brick construction with plastered thermalite blocks as the inner skin and a suspended wooden floor.
It currently has 250mm of loft insulation, 20 year old wooden
framed, double glazed windows and foam cavity wall insulation.
What’s the most cost effective way to improve things?
The room is big enough to consider over boarding the walls with
Kingspan or similar and drywalling over. I’m also considering reflooring and putting some insulation under there, but apparently it’s not as simple as I thought and you can’t just hang insulation between the joists.
Any pointers or suggestions would be welcome as I’m fed up with missus moaning about it being cold.
bobtail4x4 said:
thats a pretty good insulation standard now,
are you SURE its thermalite? as we didnt start to see them until mid 70s?
I would start with draught proofing everywhere
They are soft lightweight cement based blocks. Everyone refers to them as thermalite, but I don’t know if that’s specifically what they are.are you SURE its thermalite? as we didnt start to see them until mid 70s?
I would start with draught proofing everywhere
Start with the floor…..if your all for ripping up the flooring then board insulation between the joists is the way to go. Ive done a few but these are the only pictures i have of the last one i did.
Its 150mm. , a 50mm layer then 100 mm on top. I staggered the joints for no draughts, tile lathe fixed to the joists so you can fit it in nice and tight and it wont fall through . Expanding foam any gaps around the edge and then tape it all up. I don’t mind fitting it but i hate the dust that comes off it , really makes my skin/ eyes sore.
The key is fitting it nice and tight .
Its 150mm. , a 50mm layer then 100 mm on top. I staggered the joints for no draughts, tile lathe fixed to the joists so you can fit it in nice and tight and it wont fall through . Expanding foam any gaps around the edge and then tape it all up. I don’t mind fitting it but i hate the dust that comes off it , really makes my skin/ eyes sore.
The key is fitting it nice and tight .
I would suggest trying to understand where the heat is going.
If the foam insulation in the walls is good, then the walls are OK.
If the floor is carpet, then that should be reasonable.
I would suspect draughts and windows.
If your windows are fairly big, they can be the dominant heat loss.
In our lounge, the windows are quite big, with curtains open they generate cold air current.
Close the heavy thermal curtains which pretty much seal to the floor and window cill, it makes a big difference.
Draughts howling through the floor void, wall cavities (sorted in your case?) or loft can make a big impact.
You need ventilation, you don't need a gale.
The other thing is, maybe the heating side is just inadequate? A small, old style panel rad doesn't give out much heat at low flow temperatures.
Is the heating actually on long enough to get the room war/m?
As well as the heat loss through the walls, it takes heat to get the inner skin of the walls etc up to temperature.
A room can have mega insulation and still be cold
I had problems in the previous house. It was informative to pick a cold day and fire up a 2kW fan heater in the lounge. It gave me some numbers to work with.
Don qui Apple is right to recommend an Ir thermometer, ideal for sussing the cold surfaces.
Also a hygrometer, cheap temperature/humidity monitors can be informative.
Sometimes we process 'damp' as 'cold'. If you nail the draughts, you risk excess humidity.
Sometimes the best answer to 'cold' is 'more heat'.
If the foam insulation in the walls is good, then the walls are OK.
If the floor is carpet, then that should be reasonable.
I would suspect draughts and windows.
If your windows are fairly big, they can be the dominant heat loss.
In our lounge, the windows are quite big, with curtains open they generate cold air current.
Close the heavy thermal curtains which pretty much seal to the floor and window cill, it makes a big difference.
Draughts howling through the floor void, wall cavities (sorted in your case?) or loft can make a big impact.
You need ventilation, you don't need a gale.
The other thing is, maybe the heating side is just inadequate? A small, old style panel rad doesn't give out much heat at low flow temperatures.
Is the heating actually on long enough to get the room war/m?
As well as the heat loss through the walls, it takes heat to get the inner skin of the walls etc up to temperature.
A room can have mega insulation and still be cold
I had problems in the previous house. It was informative to pick a cold day and fire up a 2kW fan heater in the lounge. It gave me some numbers to work with.
Don qui Apple is right to recommend an Ir thermometer, ideal for sussing the cold surfaces.
Also a hygrometer, cheap temperature/humidity monitors can be informative.
Sometimes we process 'damp' as 'cold'. If you nail the draughts, you risk excess humidity.
Sometimes the best answer to 'cold' is 'more heat'.
Trustmeimadoctor said:
Imho a ir thermometer is all but useless you need a thermal camera it shows the issue more easily you can see gaps in insulation and leaks around windows and other thermal bridging
It may be all but useless in your hands......It's easy to misinterpret the pretty pictures from IR cameras.
You can 'see' a lot of stuff with an IR camera which is misleading.
Trustmeimadoctor said:
That is true
But if you can see a big patch of blue in the middle of a wall you know something's up
Just pointing an thermometer at the wall doesn't give you as much imho
True.But if you can see a big patch of blue in the middle of a wall you know something's up
Just pointing an thermometer at the wall doesn't give you as much imho
You need to use your thermometer or camera as a tool, gather the data and ask the right questions.
And be prepared to have another go if your analysis doesn't stack up.
When IR cameras first appeared, a few people I worked with used them to look at the outside of their houses, to see where the heat was getting out.
A lot of pictures were misleading, because 'hot' areas were stored heat from the day, not heat leaking out at night.
The floor
Just about Every energy performance certificate I’ve seen shows that insulating a floor where possible is cheapest & efficient - usually a 2yr payback with reduced bills.
If you don’t have an energy certificate/survey it costs about £100, or if you know a similar house that would have (either being rented or sold fairly recently) look it up on the register using a postcode & see the professionals suggestions on what to do, the cost & the expected payback.
(Insulate Britain do kinda have a point that loads of folk should insulate properties better, folk just don’t know until they’ve seen a survey )
Just about Every energy performance certificate I’ve seen shows that insulating a floor where possible is cheapest & efficient - usually a 2yr payback with reduced bills.
If you don’t have an energy certificate/survey it costs about £100, or if you know a similar house that would have (either being rented or sold fairly recently) look it up on the register using a postcode & see the professionals suggestions on what to do, the cost & the expected payback.
(Insulate Britain do kinda have a point that loads of folk should insulate properties better, folk just don’t know until they’ve seen a survey )
AndyAudi said:
The floor
Just about Every energy performance certificate I’ve seen shows that insulating a floor where possible is cheapest & efficient - usually a 2yr payback with reduced bills.
If you don’t have an energy certificate/survey it costs about £100, or if you know a similar house that would have (either being rented or sold fairly recently) look it up on the register using a postcode & see the professionals suggestions on what to do, the cost & the expected payback.
(Insulate Britain do kinda have a point that loads of folk should insulate properties better, folk just don’t know until they’ve seen a survey )
Just about every EPC I've seen has been written by cretins. Nearly as thick as the general public,Just about Every energy performance certificate I’ve seen shows that insulating a floor where possible is cheapest & efficient - usually a 2yr payback with reduced bills.
If you don’t have an energy certificate/survey it costs about £100, or if you know a similar house that would have (either being rented or sold fairly recently) look it up on the register using a postcode & see the professionals suggestions on what to do, the cost & the expected payback.
(Insulate Britain do kinda have a point that loads of folk should insulate properties better, folk just don’t know until they’ve seen a survey )
It looks as though the floor is going to be the place to start.
Theres no carpet in there at present, just wood laminate flooring and a small bedside rug.
The windows have fairly heavy curtains, but I can’t run them to the floor as the radiator is under one of them.
Another aggravating factor is that the room has a 9ft ceiling
Theres no carpet in there at present, just wood laminate flooring and a small bedside rug.
The windows have fairly heavy curtains, but I can’t run them to the floor as the radiator is under one of them.
Another aggravating factor is that the room has a 9ft ceiling
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