Talk:R-value (insulation)

I've taken the liberty of editing this, even though it's a topic on which I'm no expert. However, it's very clear that at least in New Zealand, R-value is taken to mean SI R, and nothing to do with fahrenheit or BTU. Perhaps the most contentious bit is my argument about thermal conductance through ceilings, so if any physics or building experts are out there, and I haven it terribly wrong, accept my humble apologies.--Limegreen 04:22, 26 May 2005 (UTC)[reply]

To avoid confusion, I think Wikipedia should default to SI units. 217.121.144.89 09:23, 28 May 2005 (UTC)[reply]

Good changes. I didn't want to appear like some avenging crusader, which probably impaired my clarity.Limegreen 00:17, 29 May 2005 (UTC)[reply]

F° versus °F

I think it is more proper to use the unit F° rather than °F when referring to temperature differences. One does not see this distinction made very often but it is technically correct. °F refers to a position on a temperature scale while F° refers to a unit of measure. Of course the same holds true for °C and C°. — Preceding unsigned comment added by 12.10.81.212 (talk • contribs) 2005-11-09 16:19:05 (UTC)

I don't think I've ever seen that notation used, but it sounds like something that could be very useful. Can you show any examples of where that notation is used or defined? It's rather difficult to search for on Google, since the degree symbol just gets stripped. —HorsePunchKid→龜 21:27, 9 November 2005 (UTC)[reply]

I've never seen that notation used, neither for the Celsius nor Farenheit scale. A temperature difference is in degrees Celsius; it doesn't make sense to talk about Celsius degrees. If this (distinction) is technically correct as claimed, please state your source. At least for my own part, as an energy engineer, I've never seen it in use. As an alternative to °F or °C, all temperature differences could be stated in Kelvin [K].

Incredible External Link?

Granted, it may be difficult to get a nonprofit link which is informative in such a mundane (and yet profitable) subject, but I do think that the "'R' fairy-tale" site, as hosted by an organization which seeks to profiteer off of an architectural concept (the "Monolithic Dome"), is not suitable to be linked to by an encyclopedia. Aside from discussing the "ignored" factor of convection on heat flow, the Monolithic Dome Institute does nothing other than to promote the sale of all things "Domephile." And as their financial future is dependant on their ability to promote dome-mania while dismissing weaknesses in their design, the institute does not qualify as a nonbiased source. I would recommend the replacement of those two external links with either non-profit organizations or academic sites.

"Some other countries" = "U.S."?

I think it would be useful to make it clear that the "some other countries" that use the BTU definition of R-factor include the United States. Also, I think it would be useful to give a straightforward defintion of the U.S. version of R-factor in W/m²KPciszek 19:15, 15 March 2007 (UTC)[reply]