DAK a good Heat Retaining Material

[richfool]

We live in a flat that faces north-east and therefore doesn't get much sun. One of the elevations with a patio type door to a Juliette balcony (our lounge) faces south-east and gets the sun, depending on the time of year, from about 10.00am - 12.30pm, which warms the room nicely, until the sun moves on round in the afternoon, causing the room to cool down.

I was pondering if there was any material, such as storage heater bricks, that would retain the heat well and release it slowly later, that I could position in the room, inside of the JB patio door glass? For example, I was thinking whether it would be feasible to either lay an internal patio of bricks or a suitable material (on the carpet!), or stack them to form a low wall, that would thus warm up from the sun and retain the heat and release it later. Releasing it slowly later is the key issue.

The flat is generally well insulated, with double glazing and dry linings. Rooms round the front of the building (other people's flats) can be running into the mid 20's (25C) degrees C, but we tend to drop back from 22.5-23.0 C around midday on a good sunny day, back down to 20C in the late afternoons and evenings.

Does anyone know of any suitable material or have any good ideas?

[PhaseThree]

The simple answer is water.

A more detailed answer requires knowing the heat capacity of various materials. In this instance you are probably interested in the volumetric heat capacity. This is the amount of energy a given volume of substance requires to raise its temperature by 1 degree - also known (inaccurately) as thermal mass.

See the table at this link for some values of common materials
https://energyeducation.ca/encyclopedia/Thermal_mass

As you can see stone/concrete has a value of around 2, water has a value around 4. So twice as much energy can be stored in water as can be stored in an equivalent sized lump of concrete raised to the same temperature

How about a fish tank ??

[Dod101]

The simple answer is water.

A more detailed answer requires knowing the heat capacity of various materials. In this instance you are probably interested in the volumetric heat capacity. This is the amount of energy a given volume of substance requires to raise its temperature by 1 degree - also known (inaccurately) as thermal mass.

See the table at this link for some values of common materials
https://energyeducation.ca/encyclopedia/Thermal_mass

As you can see stone/concrete has a value of around 2, water has a value around 4. So twice as much energy can be stored in water as can be stored in an equivalent sized lump of concrete raised to the same temperature

How about a fish tank ??

The fish would probably die. Is water a good radiator though, even if your advice is correct?

Dod

[PhaseThree]

The simple answer is water.

A more detailed answer requires knowing the heat capacity of various materials. In this instance you are probably interested in the volumetric heat capacity. This is the amount of energy a given volume of substance requires to raise its temperature by 1 degree - also known (inaccurately) as thermal mass.

See the table at this link for some values of common materials
https://energyeducation.ca/encyclopedia/Thermal_mass

As you can see stone/concrete has a value of around 2, water has a value around 4. So twice as much energy can be stored in water as can be stored in an equivalent sized lump of concrete raised to the same temperature

How about a fish tank ??

The fish would probably die. Is water a good radiator though, even if your advice is correct?

Dod

I was suggesting the fish tank, not necessarily the fish
The water doesn't radiate - the tank it is in radiates or more accurately convects in the same way as a standard room radiator.

[Mike4]

The simple answer is water.

A more detailed answer requires knowing the heat capacity of various materials. In this instance you are probably interested in the volumetric heat capacity. This is the amount of energy a given volume of substance requires to raise its temperature by 1 degree - also known (inaccurately) as thermal mass.

See the table at this link for some values of common materials
https://energyeducation.ca/encyclopedia/Thermal_mass

As you can see stone/concrete has a value of around 2, water has a value around 4. So twice as much energy can be stored in water as can be stored in an equivalent sized lump of concrete raised to the same temperature

How about a fish tank ??

The fish would probably die. Is water a good radiator though, even if your advice is correct?

Dod

I was suggesting the fish tank, not necessarily the fish
The water doesn't radiate - the tank it is in radiates or more accurately convects in the same way as a standard room radiator.

Surely a fish tank without fish is just "a tank"...

OB joke. Two fish in a tank. One says to the other, "You steer, I'll fire the gun".

Oops, wrong board.

[tjh290633]

The simple answer is water.

A more detailed answer requires knowing the heat capacity of various materials. In this instance you are probably interested in the volumetric heat capacity. This is the amount of energy a given volume of substance requires to raise its temperature by 1 degree - also known (inaccurately) as thermal mass.

See the table at this link for some values of common materials
https://energyeducation.ca/encyclopedia/Thermal_mass

As you can see stone/concrete has a value of around 2, water has a value around 4. So twice as much energy can be stored in water as can be stored in an equivalent sized lump of concrete raised to the same temperature

How about a fish tank ??

The fish would probably die. Is water a good radiator though, even if your advice is correct?

Dod

I was suggesting the fish tank, not necessarily the fish
The water doesn't radiate - the tank it is in radiates or more accurately convects in the same way as a standard room radiator.

If you want the tank to be most effective, it needs to have a black surface, which will both receive radiation and emit it most effectively. I guess it should also be placed in front of the window, to receive the maximum solar radiation. Then you have the problem of it radiating it's heat to the window. A curtain, perhaps?.

TJH

[kempiejon]

I remember hearing a large black water butt in the greenhouse could be used to smooth temperature fluctuations.

[AsleepInYorkshire]

A water tank would have issues in cold weather

AiY(D)

[richfool]

In terms of water tanks, I don't have a fish tank or similar, and a water butt would be too big and unsightly. It would need to be something that could be moved and perhaps part covered to look presentable.

Wouldn't a wall of stacked bricks be more practical, as well as possessing heat retaining properties? That could be part covered on the in-room side, to look like a coffee table or counter.

I recollect when living in the Far East, standing by one of our patio's rendered brick columns, late in the evening, long after the sun had set, and feeling the heat radiating off the columns (and for that matter off the wall of the house).

[88V8]

...we tend to drop back from 22.5-23.0 C around midday on a good sunny day, back down to 20C in the late afternoons and evenings.
Does anyone know of any suitable material or have any good ideas?

Leaving aside the point that 68F (20C) is a very decent temperature... what's the floor? Wood or concrete?

If it's concrete it could be quarry-tiled, that would absorb/release nicely, then a loose-lay fitted carpet or Turkey rugs for the winter.

V8

[richfool]

...we tend to drop back from 22.5-23.0 C around midday on a good sunny day, back down to 20C in the late afternoons and evenings.
Does anyone know of any suitable material or have any good ideas?

Leaving aside the point that 68F (20C) is a very decent temperature... what's the floor? Wood or concrete?

If it's concrete it could be quarry-tiled, that would absorb/release nicely, then a loose-lay fitted carpet or Turkey rugs for the winter.

V8

Those are the current spring early summer temperatures, and in the lounge which gets some sun late morning. The other rooms are cooler. I would hope that any any heat gain in the lounge would filter through to the other rooms..

The floors have fitted carpets, over I suspect, chipboard flooring, on top of concrete, - we are a mid floor flat.

[9873210]

Those are the current spring early summer temperatures, and in the lounge which gets some sun late morning. The other rooms are cooler. I would hope that any any heat gain in the lounge would filter through to the other rooms..

You should consider if you can increase air circulation between rooms. This would effectively use the rest of the building as your thermal mass, and directly address your desire to warm the other rooms.

[88V8]

Does anyone know of any suitable material or have any good ideas?

what's the floor? Wood or concrete?
If it's concrete it could be quarry-tiled, that would absorb/release nicely, then a loose-lay fitted carpet or Turkey rugs for the winter.

The floors have fitted carpets, over I suspect, chipboard flooring, on top of concrete, - we are a mid floor flat.

Ummm. So the chipboard could be removed and the concrete tiled. That would do it. But I suppose that between the chipboard and the concrete there may be services, which would complicate the process. And the cost would be high in relation to the gain, unless you plan to live there a long time.

The problem is that for a material to absorb and retain heat it must be dense.
And heavy. Even a small storage heater is a great heavy lump.

OK, here's one; an electric trainset running around the perimeter of the room, with a cargo of mini bricks. The train stops beside the window; every 30 minutes it runs to the other side of the room where the cargo is tipped into an insulated hopper and a new lot of bricks loaded, and repeat.
In the evening, open the lid of the hopper.
Needs a bit of time spending to implement the details, but you are retired, aren't you?

V8

[richfool]

Does anyone know of any suitable material or have any good ideas?

what's the floor? Wood or concrete?
If it's concrete it could be quarry-tiled, that would absorb/release nicely, then a loose-lay fitted carpet or Turkey rugs for the winter.

The floors have fitted carpets, over I suspect, chipboard flooring, on top of concrete, - we are a mid floor flat.

Ummm. So the chipboard could be removed and the concrete tiled. That would do it. But I suppose that between the chipboard and the concrete there may be services, which would complicate the process. And the cost would be high in relation to the gain, unless you plan to live there a long time.

The problem is that for a material to absorb and retain heat it must be dense.
And heavy. Even a small storage heater is a great heavy lump.

OK, here's one; an electric trainset running around the perimeter of the room, with a cargo of mini bricks. The train stops beside the window; every 30 minutes it runs to the other side of the room where the cargo is tipped into an insulated hopper and a new lot of bricks loaded, and repeat.
In the evening, open the lid of the hopper.
Needs a bit of time spending to implement the details, but you are retired, aren't you?

V8

It's a condition of the lease (leasehold flat) that the floors are carpetted with a good quality carpet and underlay, and I wouldn't want to start pulling up fixed carpets, or dismantling the floors. Point taken re use of heavy dense materials. That was why bricks had crossed my mind, or as you suggested, maybe lay some quarry tiles (laid loose not fixed), like an internal patio, on the carpet where the sun falls.

[eepee]

I wonder whether you could arrange some lightweight structure to form the basis of a Trombe Wall?

Regards,
Ernest

[Dod101]

The OP tells us in his original post that the room gets sun for only a couple of hours or so. It is not going to meaningfully heat bricks or a water tank very much in that time. I think the whole issue is a non starter. Ensure that the room is as well insulated as possible and then it should retain the warm air for longer, I should think.

Dod

[88V8]

The OP tells us in his original post that the room gets sun for only a couple of hours or so.

Good point.
But he also mentions a Juliette balcony.
Could one position solar collectors around the balcony, that would presumably extend the sun time?
Pump the heated water through a hot water cylinder.
In the evening pump the heated water from the cylinder through a radiator.
A nice little DIY project.

I recall seeing solar HW systems on the rooves of houses in Cyprus, together with a water tank. Rather like this https://www.ebay.co.uk/itm/294976569748?hash=item44adf94194:g:4FUAAOSwrFFiekyx
Although it is probably hotter in Cyprus

I agree that it might be a waste of time, but what with climate change, one never knows.

V8

[UncleEbenezer]

I recall seeing solar HW systems on the rooves of houses in Cyprus, together with a water tank. Rather like this https://www.ebay.co.uk/itm/294976569748?hash=item44adf94194:g:4FUAAOSwrFFiekyx
Although it is probably hotter in Cyprus

I agree that it might be a waste of time, but what with climate change, one never knows.

V8

I have a friend who has that in Blighty (installed back in the days when solar electric would've been an arm and a leg, if she could have got it at all).

She said it basically halved her gas bills in winter (compared to before installing it), and eliminated them altogether in summer.