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This calculation rule is mentioned in CIBSE CP1 2020 (Heat Network Code of Practice for UK), and is based on the ‘rule of thumb’ that is often used in Denmark (Varme Stabi 7th edition, 1st print 2015, published by Praxis – Nyt Teknisk Forlag 2015, see http://staabi.dk)

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Applies diversity

•  inside the dwelling
•  outside the dwelling

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