• barsoap@lemm.ee
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    1 year ago

    You know if you muppets used sane units you’d be right. But you’re using colonial measurements.

    Here’s conversion table. US R30 is equivalent to proper units R5.3, R60 is R10.5.

    …and we don’t really have recommendations as such. KfW55 is nowadays mandatory for new construction, KfW70 and up gets you cheap loans. KfW70 means less than 45 kWh/m² per year for heating and they don’t really care how you achieve that. We didn’t really get around yet factoring cooling into stuff.

      • barsoap@lemm.ee
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        1 year ago

        Your numbers still don’t make any sense or are a century out of date or something.

        The KfW also hands out loans to add insulation to existing buildings, U0.14 roof, 0.2 walls, 0.25 floor, so lowest R22.7 in Rankine land. The other numbers are for window, listed buildings, etc. All of that is minimum what’s actually recommended is well ask your architect and budget. There’s only so much that’s sensible to do when it comes to old construction as at some point hunting for air gaps and heat bridges is more bother than tearing the thing down and building new, and the KfW did set the standards sufficiently low so that currently uninsulated buildings at least get something and you can’t just tack on half a metre of insulation to an existing structure either. Mostly it’s the roof that’s missing insulation, walls tend to be defensible as they are and it probably makes more sense to upgrade the heating system.

        • jimbolauski@lemmy.world
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          1 year ago

          You can back out R values based on insulation thickness, that table may be old… It didn’t have a date on it.

          The values you provided equate to freedom R values of R40.5, R28, and R22.5 for the roof, walls, and floor. Those are inline or behind the US minimum requirements R60, R30, R20.