Radiator heat reflectors

madlyn

Czure said:

madlyn said:

Thank you everyone for your replies.
I'm looking at radflek as they have the option of sticking them to the wall or using a bracket.

Remember not to use reflectors behind radiators on internal walls OR properly insulated external walls as it has a negative effect.

Before making a final choice however I'd suggest checking out the Insulated Reflective Bubble wrap types that are coated on both sides. These not only reflect heat back into the room but also insulate the wall whilst at the same time reflecting the cold back into external walls, importantly they are for attaching to (or at least contacting with) the wall so don't need to be kept from touching them which is an absolute must for Radflex to work correctly.

I know Radflex has the hanging bars & may seem slightly easier to fit but you may find it awkward to get the correct spacing from rad' & wall with it & if you don't have enough space behind your rads for correct fitting you could end up losing heat instead of preventing loss, basically if Radflex touches the wall it conducts heat into the wall.

There's plenty of the insulated sheeting available on Amazon for around £16 for enough to do many rads & I've used it in a previous rental with excellent results, but if Radflex is preferred that's also cheaper on Amazon than direct from manufacturer website.

Make sure you check out the Amazon review by Andy R for the Radflex 5 pack, it's long but very informative & points out.

Thank you for your advice, I've found the below on Amazon which seems to fit your description.

https://www.amazon.co.uk/SuperFOIL-RadPack-Reflective-Reflector-Money-Insulates/dp/B00GUDVUXW/ref=sr_1_1_sspa?crid=2GF9A1VFRTKZ8&dib=eyJ2IjoiMSJ9.4oRjOfBtfAMM-MXVg0ze253ZEfVsrRaczWVJtI6A0pCc1q7FuVbIG6qi2v_AE4TRwEOox7i3WqjnSj9fBcJS3Ug9_vZwtvOSBIG_dSUL1Vep2Hg4puFS0BxgMUurOvyc_XRPp8t5mZHsMDvIp-0opDvRkE4fteZ1X_-Z0NYWkc-WIpIRZER0us2HPJ-_L3wEnjabtaYoEYTeR3Wg4b8v6s3D_umz79Ap1sUKgy9dtU5JHBrp1sZnT_dLOdewmNyYWYI9PMBKEqKJ49igxufrlaLqXR30GO2IVjU9s7CfMJc.4rkhXamPF8qnCmXeGG_gfvtEU51i8ip1oVGPcUP0Zn8&dib_tag=se&keywords=superfoil&nsdOptOutParam=true&qid=1732297193&sprefix=superfoil,aps,119&sr=8-1-spons&sp_csd=d2lkZ2V0TmFtZT1zcF9hdGY&psc=1&smid=A39IZ27BZDGWD0

Czure

madlyn said:

Czure said:

madlyn said:

Thank you everyone for your replies.
I'm looking at radflek as they have the option of sticking them to the wall or using a bracket.

Remember not to use reflectors behind radiators on internal walls OR properly insulated external walls as it has a negative effect.

Before making a final choice however I'd suggest checking out the Insulated Reflective Bubble wrap types that are coated on both sides. These not only reflect heat back into the room but also insulate the wall whilst at the same time reflecting the cold back into external walls, importantly they are for attaching to (or at least contacting with) the wall so don't need to be kept from touching them which is an absolute must for Radflex to work correctly.

I know Radflex has the hanging bars & may seem slightly easier to fit but you may find it awkward to get the correct spacing from rad' & wall with it & if you don't have enough space behind your rads for correct fitting you could end up losing heat instead of preventing loss, basically if Radflex touches the wall it conducts heat into the wall.

There's plenty of the insulated sheeting available on Amazon for around £16 for enough to do many rads & I've used it in a previous rental with excellent results, but if Radflex is preferred that's also cheaper on Amazon than direct from manufacturer website.

Make sure you check out the Amazon review by Andy R for the Radflex 5 pack, it's long but very informative & points out.

Thank you for your advice, I've found the below on Amazon which seems to fit your description.

https://www.amazon.co.uk/SuperFOIL-RadPack-Reflective-Reflector-Money-Insulates/dp/B00GUDVUXW/ref=sr_1_1_sspa?crid=2GF9A1VFRTKZ8&dib=eyJ2IjoiMSJ9.4oRjOfBtfAMM-MXVg0ze253ZEfVsrRaczWVJtI6A0pCc1q7FuVbIG6qi2v_AE4TRwEOox7i3WqjnSj9fBcJS3Ug9_vZwtvOSBIG_dSUL1Vep2Hg4puFS0BxgMUurOvyc_XRPp8t5mZHsMDvIp-0opDvRkE4fteZ1X_-Z0NYWkc-WIpIRZER0us2HPJ-_L3wEnjabtaYoEYTeR3Wg4b8v6s3D_umz79Ap1sUKgy9dtU5JHBrp1sZnT_dLOdewmNyYWYI9PMBKEqKJ49igxufrlaLqXR30GO2IVjU9s7CfMJc.4rkhXamPF8qnCmXeGG_gfvtEU51i8ip1oVGPcUP0Zn8&dib_tag=se&keywords=superfoil&nsdOptOutParam=true&qid=1732297193&sprefix=superfoil,aps,119&sr=8-1-spons&sp_csd=d2lkZ2V0TmFtZT1zcF9hdGY&psc=1&smid=A39IZ27BZDGWD0

That's the stuff, it works a treat. Buy it on Subscribe & Save to save a couple of quid then cancel the subscription once it arrives.

bjorn_toby_wilde

Czure said:

madlyn said:

Thank you everyone for your replies.
I'm looking at radflek as they have the option of sticking them to the wall or using a bracket.

Remember not to use reflectors behind radiators on internal walls OR properly insulated external walls as it has a negative effect.

Before making a final choice however I'd suggest checking out the Insulated Reflective Bubble wrap types that are coated on both sides. These not only reflect heat back into the room but also insulate the wall whilst at the same time reflecting the cold back into external walls, importantly they are for attaching to (or at least contacting with) the wall so don't need to be kept from touching them which is an absolute must for Radflex to work correctly.

I know Radflex has the hanging bars & may seem slightly easier to fit but you may find it awkward to get the correct spacing from rad' & wall with it & if you don't have enough space behind your rads for correct fitting you could end up losing heat instead of preventing loss, basically if Radflex touches the wall it conducts heat into the wall.

There's plenty of the insulated sheeting available on Amazon for around £16 for enough to do many rads & I've used it in a previous rental with excellent results, but if Radflex is preferred that's also cheaper on Amazon than direct from manufacturer website.

Make sure you check out the Amazon review by Andy R for the Radflex 5 pack, it's long but very informative & points out.

I’m interested by some of your comments, mainly because I don’t really understand the science behind them.

1. How can using reflectors behind a radiator on an internal wall or a “properly insulated external wall” have a negative effect?

2. How would Radflek touching the wall conduct heat into it?

3. Cold is by definition the absence of heat, so how can cold be “reflected back into external walls”?

Can you tell me what your sources are for these statements?  Just looking to understand the evidence base.

Descrabled

Radiators in this context are badly named because the heat transfer is predominantly by convection. Cold air in contact with the metal surface heats up and rises due to boyancy or chimney effect. Colder air is drawn in at the bottom of the radiator rises and warmer air exits from the top of the radiator.

So for good heating conditions there must be no obstruction to the air circulation. No furniture against the radiator, no shelves over the top and don't fill the area between the radiator and the wall because any of these will inhibit air circulation around the metal parts of the radiator. Especially never put a cover over the top of the radiator.

Czure

bjorn_toby_wilde said:

Czure said:

madlyn said:

Thank you everyone for your replies.
I'm looking at radflek as they have the option of sticking them to the wall or using a bracket.

Remember not to use reflectors behind radiators on internal walls OR properly insulated external walls as it has a negative effect.

Before making a final choice however I'd suggest checking out the Insulated Reflective Bubble wrap types that are coated on both sides. These not only reflect heat back into the room but also insulate the wall whilst at the same time reflecting the cold back into external walls, importantly they are for attaching to (or at least contacting with) the wall so don't need to be kept from touching them which is an absolute must for Radflex to work correctly.

I know Radflex has the hanging bars & may seem slightly easier to fit but you may find it awkward to get the correct spacing from rad' & wall with it & if you don't have enough space behind your rads for correct fitting you could end up losing heat instead of preventing loss, basically if Radflex touches the wall it conducts heat into the wall.

There's plenty of the insulated sheeting available on Amazon for around £16 for enough to do many rads & I've used it in a previous rental with excellent results, but if Radflex is preferred that's also cheaper on Amazon than direct from manufacturer website.

Make sure you check out the Amazon review by Andy R for the Radflex 5 pack, it's long but very informative & points out.

I’m interested by some of your comments, mainly because I don’t really understand the science behind them.

1. How can using reflectors behind a radiator on an internal wall or a “properly insulated external wall” have a negative effect?

2. How would Radflek touching the wall conduct heat into it?

3. Cold is by definition the absence of heat, so how can cold be “reflected back into external walls”?

Can you tell me what your sources are for these statements?  Just looking to understand the evidence base.

1. Thermal Mass.
 Internal walls should be allowed to absorb heat so they can slowly release it back into the home once heating switches off. Likewise the same applies to the inside surface of insulated external walls (as long as quality insulation has been correctly installed). Foil insulation behind radiators on these walls drastically slows down or prevents thermal mass building up thus losing or reducing a valuable free source of heating. Of course it's not free to build that thermal mass up in the first place as it only builds internally whilst running a heating system, but it becomes free & reduces costs by increasing the length of time before the system needs to fire back up by slowly releasing it's stored heat in the same way that electric storage heaters do.

2. Radflek's laminated to give it strength & some rigidity but unlike the bubble wrap type it has no insulating air pockets sandwiched between the layers, so although it still deflects heat back when it's in contact with an un-insulated external wall it'll lose more of it's absorbed heat into the wall than the bubble types when installed in the same way.
 This is why Radfleks instructions say to leave 25mm gaps both front & rear, obvious why the front gap's needed but the rear gap's to help it overcome it's lack of air pockets. But if you install a bubble type with those same gaps it'll again be more efficient.

3. I should've said 'conducting' instead of reflecting it back I guess so stand corrected.

 As for sources you'll find more than you could ever wish for on the www. Obviously there's some dodgy ones as always but for the most part & on any reputable company or source you'll find the info you need to confirm the above as it's pretty simple thermodynamics.
 Incidentally, the sources mentioned in Radfleks Amazon advert & as mentioned by the review I referred to I looked at myself to see if any mention of Radflek could be found & I couldn't find anything!

I spent 2 winters with thick Radflek type insulation (not that brand though but correctly installed) & am now on my 4th winter with the bubble type (just stuck to walls behind rad's) & I can definitely say it's better even fitted in that way.

bjorn_toby_wilde

That’s interesting. I wasn’t aware of the idea of building up thermal mass in internal walls and that makes sense.

I’ll take a look for references on Radflek. Their fitting literature didn’t seem to mention the air gap when I was fitting it (not that I recall anyway) so surprising that it’s on their website.  They should make more mention of this.

Re. 3 the point is that cold is not a form of energy or a physical property and cannot be reflected or conducted. Cold is the absence of heat.  Heat energy can be conducted or reflected. Cold can’t because it’s isn’t a form of energy.