Wall insulation: R-14.2 or R-22.7?
I’m after some advice on whether I should shell out the extra money to bring my walls up to R22.7. My all my walls are 3 inch concrete with no insulation at the moment. I am planning on having kooltherm k5 external cladding installed. This comes in R14.2 or R22.7. I currently have R22.7 batts in the roof. My house is located in Melbourne Australia, the local sustainable building guide recommend R15.9 for walls. The R22.7 is about 25% more expensive. So I’m looking an extra $1500-$2000 for the 22.7. So do you think it is worth putting the extra money in for the 22.7 or save that money? Maybe put it towards double glazing or underfloor insulation? Note all R values are imperial not metric. PS. When is America giving up on imperial and joining the rest of the world on metric? It’s a pain converting everything but worth it for the good advice one this forum. 🙂
Edit adding metric R-values as it seems like lots of non Americans on this forum
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