Sun, 03 May 2026 09:53:34 +0100 https://www.greenbuildingforum.co.uk/newforum/ Lussumo Vanilla 1.0.3 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=938&Focus=10201#Comment_10201 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=938&Focus=10201#Comment_10201 Sun, 02 Dec 2007 13:55:05 +0000 Jeff B
Jeff B.]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=938&Focus=10207#Comment_10207 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=938&Focus=10207#Comment_10207 Sun, 02 Dec 2007 14:31:36 +0000 passivhausfan
I imagine they could work to some extent. Using low e glass for single glazing with the low-e coating facing into the room is thought to have some effect, and this is analogous. I am not saying they do work, though. Maybe someone could test this?

However, to the extent that they work, they must do this by reducing heat transfer from the interior of the room to the surface of the wall. They don't affect the conductivity of the wall, so this means they must reduce its surface temperature. So in fact, they'll probably make condensation worse!]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=938&Focus=10467#Comment_10467 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=938&Focus=10467#Comment_10467 Wed, 05 Dec 2007 16:50:17 +0000 passivhausfan
www.electro-optical.com/bb_rad/emissivity/matlemisivty.htm

the emissivity of water is about 95%, so if you do get condensation, that presumably renders the paint ineffective, at least where it's actually covered by water.]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=938&Focus=10471#Comment_10471 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=938&Focus=10471#Comment_10471 Wed, 05 Dec 2007 17:48:14 +0000 fostertom https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=938&Focus=10516#Comment_10516 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=938&Focus=10516#Comment_10516 Thu, 06 Dec 2007 17:13:46 +0000 Jeff B
www.thermilate.com

I am tempted to get some of the powder additive variety (rather than the ready-to-use paint) just for the heck of it, mixing it with some emulsion paint and painting the inside of the external walls in one room as an experiment. I have an infra red thermometer so I could do a crude "before and after" check. The product apparently contains hollow microspheres of a ceramic material. The interior of the sphere is a vacuum so the theory is that after the paint dries you are left with a thin layer of mini-Dewar flasks on the wall!

I was rather hoping another Forum reader had already tried it but it appears not, from the lack of responses to date.

Jeff B.]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=938&Focus=10518#Comment_10518 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=938&Focus=10518#Comment_10518 Thu, 06 Dec 2007 17:57:09 +0000 passivhausfan
"Q. What is the texture, when Thermilate is mixed into paint?
A. The texture is ever so slightly rough, most of our customers don’t even notice the difference, however some prefer to apply another final coat of paint, without Thermilate mixed in, for a perfect flat finish."

Presumably this works on the same principle as under-slab multifoil...]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=938&Focus=10558#Comment_10558 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=938&Focus=10558#Comment_10558 Fri, 07 Dec 2007 08:55:53 +0000 fostertom https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=938&Focus=10560#Comment_10560 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=938&Focus=10560#Comment_10560 Fri, 07 Dec 2007 09:04:32 +0000 caliwag At the time we did recommend extraction of humidity at source so he may well have tackled that at the same time...so a bit inconclusive really. I will seek out the thread.]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=938&Focus=10575#Comment_10575 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=938&Focus=10575#Comment_10575 Fri, 07 Dec 2007 13:18:50 +0000 Jeff B
Jeff B.]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=938&Focus=10576#Comment_10576 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=938&Focus=10576#Comment_10576 Fri, 07 Dec 2007 14:12:39 +0000 fostertom https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=938&Focus=10577#Comment_10577 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=938&Focus=10577#Comment_10577 Fri, 07 Dec 2007 14:38:23 +0000 passivhausfan
I've found a reference for the increased condenstation issue:

http://www.pilkington.com/europe/uk+and+ireland/english/building+products/forhouseholders/frequently+asked+questions/windows.htm#faq3

"If Pilkington K Glassâ„¢ is used in single glazing with the coating facing the room, it may also promote the formation of condensation. This is because the coating acts as a barrier to heat, keeping the glass colder than ordinary single glazing. Because the surface is colder, condensation will form more readily and in larger quantities than on ordinary single glazing."

The same thing would happen with a low-e wall coating.

I would be interested to see a test of the principle of this. If anyone's got a temperature probe, how about putting two sheets of tinfoil, one with a coating of emulsion paint, against a cold exterior masonry wall and seeing whether the area with the tinfoil showing is significantly colder than the one with it covered. If not, that would tend to invalidate the claims. If so it would be easy to use the external temperature to work out the difference in heat transfer and hence the percentage saving.]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=938&Focus=10582#Comment_10582 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=938&Focus=10582#Comment_10582 Fri, 07 Dec 2007 15:58:26 +0000 fostertom Posted By: fostertomAdd that to min 75 of sprayed hemcrete internally plus airtight external repointing, we begin to get somewhere worthwhile with internal insulation (where it can't be done externally) without loss of benefit of the wall's thermal massivenessOn second thought, not so sure - leaving aside the effect on U-value for a moment, would a more emissive inner surface tend to cut off the interior from benefit of the wall's thermal massiveness?

How can ceramic bubbles affect the wall's emissivity if the bubbles are themselves coated with paint of probably high emissivity, facing into the room?]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=938&Focus=10583#Comment_10583 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=938&Focus=10583#Comment_10583 Fri, 07 Dec 2007 16:03:08 +0000 Jeff B
Like Fostertom I am rather sceptical of course, but for approx. £13 per pack (which buys enough additive to treat 5 litres of emulsion paint) I am prepared to take a gamble.I did try asking for a small sample to test but my request was denied on the grounds that I was not a representative of a paint manufacturing company!

Jeff B.]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=938&Focus=10587#Comment_10587 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=938&Focus=10587#Comment_10587 Fri, 07 Dec 2007 17:06:47 +0000 caliwag insulation and ventilation
heat insulation
single brick outbuilding...23 Jan 07

One day I'll learn how to paste the link...hope you locate it]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=938&Focus=10595#Comment_10595 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=938&Focus=10595#Comment_10595 Fri, 07 Dec 2007 18:02:36 +0000 Jeff B
Jeff B]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=938&Focus=45208#Comment_45208 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=938&Focus=45208#Comment_45208 Thu, 29 Jan 2009 09:43:21 +0000 Nick Parsons https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=938&Focus=45215#Comment_45215 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=938&Focus=45215#Comment_45215 Thu, 29 Jan 2009 10:17:38 +0000 PaulT
Since producing the thesis I have done more research and also have a thermal imaging camera.

I have been able to establish that the surface emissivity does not change significantly, but unlike multifoil I can establish a measurable change in the thermal resistance of the surface boundary and can also track differences in the admittance rate (effective thermal mass).

http://thehealthyhome.co.uk/downloads/MSCThesisPLT.pdf]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=938&Focus=45309#Comment_45309 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=938&Focus=45309#Comment_45309 Thu, 29 Jan 2009 17:51:11 +0000 James Norton Sempatap"- work in this way Paul...?

(of course afters it's given you spongy walls, killed you with fumes in a house fire and destroyed your respiratory tracts with hidden mould spores... )

J]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=938&Focus=45335#Comment_45335 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=938&Focus=45335#Comment_45335 Thu, 29 Jan 2009 20:41:13 +0000 Gotanewlife https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=938&Focus=45342#Comment_45342 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=938&Focus=45342#Comment_45342 Thu, 29 Jan 2009 21:13:51 +0000 Jeff B
Funnily enough I have only this week just painted the walls in our kitchen/diner and, because I have some Thermilate left over, I have painted the exterior wall with 2 coats of emulsion containing 10% Thermilate. Not that we have any condensation problems at all, but why not - just for the heck of it really! It does produce a slightly coarse texture to the finish but as the walls in this room appear to have been painted (by the previous owner) with a job lot of yellow Sandtex exterior wall paintthen, if anything, the surface has actually been smoothed a little!]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=938&Focus=45394#Comment_45394 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=938&Focus=45394#Comment_45394 Fri, 30 Jan 2009 10:56:57 +0000 PaulT
This factor alon will make the home more responsive to heating.

The change in overal U value is big because the original U value is so poor!

The surface resistance of a wall is set at R = 0.13

I found with our paint samples this increased to R = 0.3

So we have added the equivalent of R = 0.17

An R value of 0.17 is actualy quite a bit more than 3mm of EPS (6mm), but caution prevails... plus who would beleive me?

- The important issue here is that because the layer is so small I am adjusting the surface boundary conditions rather than adding a distinct layer of insulation. This is an important distinction and takes us into a complicated area of physics and is, in my view, a reason for misleading claims on how other additives work. My interpretation is not strictly correct, but maybe closer than others. For a full explanation take a look at my post on the decrement thread.]]>