THE INFLUENCE ON BUILDING THERMAL-BEHAVIOR OF THE INSULATION MASONRY DISTRIBUTION IN A 3-LAYERED CONSTRUCTION/

Building envelopes are most often of a layered construction,, the laye rs often consisting of insulation and masonry. This study investigates the influence of layer distribution and relative thickness of the ins ulation/masonry on the thermal behavior of the building and plant capa city. To evaluate this influence we have assumed that the overall thic kness and the thermal transmittance (U value) of a three-layered build ing envelope are constant, but have varied the relative thickness and positions of masonry and insulation within the structure. Two structur es were investigated: masonry/insulation/masonry, and insulation/mason ry/insulation. The computer program BRE-ADMIT was employed; this progr am is based on the admittance procedure for analyzing building thermal behavior. Figures for the daily energy consumption in a single zone b uilding together with the maximum power requirement are presented for the ranges of structures tested. It is shown that, for intermittent he ating plant operation as opposed to intermittent cooling plant operati on, the insulation/masonry/insulation structure saves 32-72% more ener gy compared with the masonry/insulation/masonry structure. For intermi ttent heating and cooling plant operation, a position can be found for the insulation layer within masonry/insulation/masonry structure, suc h that daily energy consumption is minimized but plant power requireme nt is maximized. Designers may find it helpful to be aware of these ef fects when designing buildings. (C) 1997 Elsevier Science S.A.