Technical Booklet F1 Conservation of Fuel and Power in Dwellings·Page 34·2.57
Party walls separating dwellings and thermal bypasses
Cavity walls separating dwellings (party walls) cannot have zero heat loss due to thermal bypass from air movement in the cavity. Fully filling the cavity may affect sound transmission through the party wall.
Cavity walls separating dwellings (hereafter referred to as party walls) may not have zero heat loss because a thermal bypass is created where there is air movement in the cavity. Fully filling the cavity may have implications for sound transmission through the party wall.
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