Book - School of Science and Technology

Solar heat gains 831001 d = 02 d = 0.4h (all faces)3 d = 0.4h (S face only)4 d = 0.8h (all faces)5 d = 0.8h (S face only)1 23Cooling load %54(n+1)thFloor slabStoreynthStoreyhd6 8 10 12 14 16 18 20Sun timeFigure 3.8 Effect of horizontal projections upon cooling loadTable 3.8 Effect of structural shading upon annualenergy consumption for coolingMethod of shadingType Depth (mm) Annual indexNo shading 1.0Window recess 150 0.94500 0.821000 0.68Vertical fins 150 0.97500 0.941000 0.88Horizontal overhang 500 0.871000 0.762000 0.57Building shapeDeep plan constructions, generally single-storey, have been a commonplace approach toindustrial building for many years. In most cases room heights are generous, daylight isavailable from roof glazing and occupancy levels per unit of floor level are low. Simpleheating and ventilating systems will thus, in the majority of cases, provide adequateservice. As to solar gain through roof glazing in medium to heavy industrial buildings,experimental work at the (then) Building Research Station*demonstrated that applicationof two coats of whitewash, with a suitable binder such as tallow, to the outer surfacewould reduce solar overheating by about 70%.*Beckett, H. E., `The exclusion of solar heat', JIHVE, 1935, 3, 79.