For the purpose of this seminar I am going to study the environmental performance for a house of 140 m2 I designed which is currently being under construction. During the design of the house I used the theoretical backgound of sustainable design.In this assignment I am going to use Ecotect in order to 1) assess the so far design choices made 2) optimise the environmental performanceof the design through moderate changes in shading elements types and materials.
One of the most important decisions in design was the house’s orientation. In order to maximize the solar gains in winter and minimise them during summer the houses largest percentage of openings were orientated towards the south.
summer incident solar radiation
winter incident solar radiation
In a diagramatical comparison of the total incident solar radiation expressed in cumulative values we see in the summer the house gets less exposed to incident solar radiation than in the winter due to its orientation.
By conducting thermal analysis on the actual orientation of the house we get total number of 17296932 Wh for heating and cooling gains on a fully airconditioning model.
On a hypothetical 37 deg rotation of the North (which would place the house orthogonally to the site) the same analysis we get the sum of 16247432 Wh
Although, the same analysis on an only heating model proves that the thermal confort is covered by a percentage of that ranges from 86.2% to 89.6% . The conclusion could be that the house could function without cooling systems supporting it.
annual distribution of temeratures in fully air-conditioned model (zone6)
On a hypothetical 37 deg rotation of the North (which would place the house orthogonally to the site) the same analysis proves that the percentage of thermal confort drops to 82.5%-87.9% while the thermal analysis on the actual orientation of the house provides a number of 17296932 Wh for heating and cooling gains on a fully air-conditioning model.
For the master bedroom (zone 5) two different types of shading were tested through the software: vertical and rotated louvres.
VERTICAL LOUVRES
HOURLY TEMPERATURES – Saturday 30th June (181)
Zone: Zone 5
Avg. Temperature: 26.1 C (Ground 17.9 C)
Total Surface Area: 86.400 m2 (540.0% flr area).
Total Exposed Area: 56.800 m2 (355.0% flr area).
Total South Window: 0.000 m2 (0.0% flr area).
Total Window Area: 3.340 m2 (20.9% flr area).
Total Conductance (AU): 84 W/°K
Total Admittance (AY): 322 W/°K
Response Factor: 3.57
ROTATED LOUVRES
HOURLY TEMPERATURES – Saturday 30th June (181)
Zone: Zone 5
Avg. Temperature: 26.1 C (Ground 17.9 C)
Total Surface Area: 86.400 m2 (540.0% flr area).
Total Exposed Area: 56.469 m2 (352.9% flr area).
Total South Window: 0.000 m2 (0.0% flr area).
Total Window Area: 3.340 m2 (20.9% flr area).
Total Conductance (AU): 83 W/°K
Total Admittance (AY): 321 W/°K
Response Factor: 3.58
From the comparison in these two cases we see a minimal increase on the responce factor and a 0.331 m2 decrease on the exposed area. Therefore the impact of the orientation of the louvres is minimal on a horisontal placement.