BUSM4468 SUSTAINABLE FACADES AND MATERIALS
FORMIT PRO MODELLING 8AM JANUARY
8AM JULY
N
N
12PM JANUARY
12PM JULY
N
N
As technology advances and interests in sustainable building rise, Building Information Modelling (BIM) software usage and development has been steadily increasing. One of such softwares is FormIt Pro, a modelling software developed to be used as a conceptual design tool which is capable of producing solar and energy analyses. FormIt has been used to analyse the Flemington Commission flats and to better understand the solar radiation values and thus better predict the viability of installing technologies such as solar photovoltaic panels. The first stage of the analysis looks at how solar gains are impacted by shading - the images provided show the impact of shading at 8AM in the morning and 12PM in the afternoon during one Summer and one Winter month. It is shown that only during Winter, where the sun path is lower in the sky, shading is cast onto the tower being analysed - with this shading only being cast on lower levels. Therefore, it is safe to assume that the surroundings have a minimal affect on the amount of solar radiation cast onto the building. The second stage of the analysis looks at the solar radiation values of the building during different times of the year. The images shown below represent the yearly cumulative, Summer, Autumn, Winter and Spring radiation values, with the values for each facade (plus roof) graphed below the corresponding model image. The model below is looking primarily at the
YEARLY CUMULATIVE
JANUARY
south eastern corner of the building. The data shows that the roof consistently gets high values of solar radiation, with the lowest amount being 361.1Wh/sqm (during July) and the highest being 907.3Wh/sqm (in January). When looking at the yearly cumulative, the solar radiation value surpasses the values for the facades at 1297Wh/sqm. Installation of solar panels on the roof would have a reasonable return, but consideration also needs to be taken in regards to the lift motor room placed on the roof, as this restricts the amount of usable space for solar panels. Solar radiation on the northern facade varies according to the sun’s angle in the sky - in Summer where the sun path is high in the sky, the northern facade receives 286.6Wh/sqm compared to in Winter where it receives 536.5Wh/sqm. However when looking at the yearly cumulative, the northern facade values are higher than the values for the eastern and western facade. Due to the large variation in the northern solar gains, it is recommended to install an adjustable shading device so that sunlight can be maximised during winter and reduced during summer. The southern facade, as expected, has very low levels of solar radiation and thus ensuring that facade is well insulated and has high performance glazing can assist in preventing the amount of heat losses throughout the building.
APRIL
OCTOBER
JULY
1400
1200 1100 1000
1000
900
900
900
800 700 600 500 400 300 200 100 0 NORTH
EAST
SOUTH
WEST
ROOF
800 700 600 500 400 300 200 100 0 NORTH
EAST
SOUTH
WEST
ROOF
800 700 600 500 400 300 200 100 0 NORTH
EAST
SOUTH
WEST
ROOF
Radiation Values (Wh/sqm)
1000
900
Radiation Values (Wh/sqm)
1000
900
Radiation Values (Wh/sqm)
1000
Radiation Values (Wh/sqm)
Radiation Values (Wh/sqm)
1300
800 700 600 500 400 300 200 100 0 NORTH
EAST
SOUTH
WEST
ROOF
800 700 600 500 400 300 200 100 0 NORTH
EAST
SOUTH
WEST
ROOF
STAGE TWO KIM NGUYEN S3332948
BUSM4468 SUSTAINABLE FACADES AND MATERIALS
SKETCHUP/SEFAIRA ANALYSIS The development and utilisation of building modelling softwares in conjunction with an increased awareness of sustainable building practices in recent years has been resulting in building design with which more thoroughly considers energy efficiency and environmental impact across all stages of the building lifecycle. This analysis uses Sketchup, a rather basic modelling software, with the addition of the Sefaira Plugin to provide analytical data on the Flemington commission flats in regards to energy loads and natural daylighting capacity. The first analysis looks at the Flemington commission flats as currently constructed and assumes envelope and equip-
ment properties as specified on the slider diagram on the left. As it is not feasible to do an analysis of every single floor, four have been chosen to analyse - the ground floor, level 7, level 14 and the top floor (level 21). The daylighting diagram shows that there are some issues with overlighting along the corridors with Eastern/Western facing windows (30% overlit). The analysis also shows that it is mostly the central areas which are underlit. Annual energy usage totals to 135kWh/m2/year but this value only takes into account the four floors being analysed and ignores the other 17 floors.
100%
250000
90% 80% Floor Area (%)
200000 144852
150000
100000 56280 50000
30291
25838
WELL LIT
+ 5%
OVERLIT
-11%
Energy Use Improvement (kWh/year) HEATING
- 7.69%
COOLING
- 49.08%
LIGHTING
- 40.83%
- 17.15%
PUMPS
- 38.63%
TOTAL
- 18.28%
16930
Underlit
Well lit
Overlit
All energy reductions are beneficial - with one neutral value being the lack of change in equipment loads. However, the new shading proves overall to be a positive change, reducing the total building energy usage from 135kWh/ m2/year to 110 kWh/m2/year, an approximately 18% energy reduction. If Sefaira constrains were unlimited, it would be interesting to see the correlation between facade area shaded and energy decrease/increase and to find the optimum shaded areas in regards to performance.
90% 80%
200000
Floor Area (%)
Energy Consumption (kWh/yr)
4%
100%
150000
100000
85711 51951 21406
10390
71%
70% 60% 50% 40% 30% 20%
15423
Pumps
Fans
Equipment
Lighting
Cooling
Heating
PROPOSED
30%
30%
0%
214278
0
40%
10%
250000
50000
50%
The two tables on the left show the building performance improvement after the installation of the shading fins - with the amount of overlit floor space reducing by 11% and the amount of underlit spaces increasing by 6%. This means that overlit spaces will not have as much solar heat gains as in the original design and this improvement can be seen in the cooling loads - where they are reduced by almost half. As the amount of well lit spaces has also increased, this has resulted in lighting loads reduced by 40%.
EQUIPMENT - 0 % FANS
60%
20%
Pumps
+ 6%
66%
70%
The second stage of analysis involves designing additional shading systems to be installed and analysing the thermal and energy usage benefits of the proposed design. Due to the overlighting issues, a series of shading fins have been installed onto certain areas of the East and West facade, primarily in corridor spaces, to reduce the amount of sunlight infiltrating the building. Certain constraints with Sefaira meant that the amount of fins were limited with a limit of 500 shading devices allocatable per analysis. The analysis shows
Daylighting Improvement (% floor area) UNDERLIT
Fans
Equipment
Lighting
Heating
0
Cooling
EXISTING
Energy Consumption (kWh/yr)
214278
10%
19% 10%
0% Underlit
Well lit
Overlit
STAGE THREE KIM NGUYEN S3332948
BUSM4468 SUSTAINABLE FACADES AND MATERIALS
REVIT/SEFAIRA ANALYSIS
350000 300000 250000 200000 150000 100000 50000 0 Pumps
Fans
Equipment
Lighting
Cooling
Heating
60 50 40 30
191 kWh/m2/yr
20
BEFORE
10 0 Underlit
Well lit
Overlit
350000 300000 250000 200000 150000 100000 50000 0 Pumps
Fans
Equipment
Lighting
Cooling
Heating
60 50 40 30 20
185 kWh/m2/yr
AFTER
10 0 Underlit
The final stage of the analysis involves uing Revit to model the Flemington Commission Housing flats. After modelling the flats, changes will be made to the facade and an analysis through Sefaira will be undertaken to examine the energy performance and daylighting factor in both the existing situation and the proposed development. As with Stage 3, all the levels will be modelled but only the Ground floor, Level 7, Level 14 and the top floor will be simulated due to software limitations.
For the proposed upgrade, the Eastern and Western portions of the facade which are connected to the hallway will be changed from concrete/masonry walls to a glazed curtain wall system with horizontal louvres.
The results indicate that the upgrade will result in an overall energy usage reduction of 6kWh/m2/yr. This is due to a reduction in heating and cooling loads, fan energy usage and pump energy usage. Interestingly, depite an increase in percentage of well lit areas, there is no reduction in lightThe model for the existing situation utilises the same dimen- ing energy loads. Underlit areas reduce by alomst 44% with sions as the model in Stage 3 and the building material pathe upgrade and an increase of well-lit and overlit areas are rameters are inserted as shown at the top of the poster, with 22.73% and 60% respectively. parameters slightly differing between the existing and proposed situations.
Well lit
HEATING COOLING FANS PUMPS
Overlit
↓ 6.23% ↓ 2.13% ↓ 2.93% ↓ 7.24%
UNDERLIT
↓ 43.90%
WELL-LIT
↑ 22.73%
OVERLIT
↑ 60.00%
STAGE FOUR KIM NGUYEN S3332948