PURSUIT OF SUSTAINABILITY!
Environment II
University of Adelaide
J. Douglas-Hill
Study of a Building’s Thermal Performance Building Introduction
ADELAIDE
LAT LONG
34° 54’ S 138° 35' E
Current Issues
Result 1
This inves)ga)on looks at a building in regards to its environmental performance and sustainability.
The Current Building (no modifica+ons) A simula)on using Apache was run throughout a typical summer and winter season of Adelaide. Results for indoor temperatures from both bedrooms and the ground floor living space can easily reach over 45°C during mid-30° days. Even in winter, the building seems to heat up at an increasing rate on 20° days. The temperature can fluctuate 10° almost hourly, with freezing cold dips of 12°C.
T h i s fi rs t m o d i fi c a ) o n included a simple shade which was added to the north face. This local shade successfully blocked most direct light in summer while maintaining it during winter.
Air Temperature: Bedroom 1st floor, Bedroom 2nd floor & Living Space
To modify the thermal mass of the building, all external walls were subs)tuted with double-brick wall.
Summer & Winter Room Temperatures
Winter: Outside Dry-bulb Temperature
! ! !
Summer: Outside Dry-bulb Temperature
The case, a medium sized three-storey townhouse, sustains environmental shortcomings, where the building lacks thorough thermal performance, lacks proper shading, and magnifies the effects of seasonal weather. While it accommodates unique and pleasing internal spaces, it falls short when it comes to energy efficiency and environmental sustainability due to the need for frequent hea)ng and cooling system usage, motorised shading and more. The building is built of a lightweight steel structure with corrugated steel cladding and R1 insula)on. All glass is single glazed. The floor is a 100mm concrete founda)on on 100mm of sand, and the above levels consist of uninsulated )mber flooring.
! ! !
Date : January & February
Date : June, July & August
This buildings weather intolerance and tendency to severely intensify warm days and direct sunlight show a full lack of airflow with outside air, lack of shading where and when it is needed, and an improper use of thermal insula)on in rela)on to the buildings thermal mass.
Date : January & February
Date : June, July & August
It is interes)ng to note that the original building has steel cladding walls with insula)on board, and this double-brick contains just a 40mm air cavity. Re s u l t s a b o ve s h o w e d t h e double brick had very similar thermal proper)es to the original building, however seemed to perform slightly beKer – maintaining heat in winter and slightly slowing thermal variance.
!
Assignment 1 Shading Testing Summer
The shading designed for the north wall did help well in reducing the extent of temperature increase. The maximums decreased appreciably by around 3°C for most hot days.
! !
9:00am!!
!
12:00pm!
!
!
3:00pm
Winter
Comments While the double-brick change was quite a significant altera)on, it did not solve the issue with the building. The change from the original lightweight steel structure increased the thermal mass and appeared to match the thermal performance despite the removal of R1 insula)on.
The model above was made as proof of concept to solve the issue of shading. This was tested under Adelaide sun and blocked direct summer light into the building, while allowing it in June-August.
!
9:00am!!
!
12:00pm!
!
!
3:00pm
Shading did help no)ceably, but it was not enough – much light entered the building both through the eastern windows and in the mornings and aQernoons in summer. In winter, the effects of the shading was less prevalent because of the fact it only blocked morning sunlight an insignificant amount.
Environment II
Result 2
Result 3
In a second modifica)on, the shading development design from Assignment 1 was assigned to the IES model.
This final modifica)on consisted of mul)ple small altera)ons to the design. The south side of the building had changes to each window. Since much of t h e f a c a d e w a s g l a s s , m o d i fi c a ) o n s s u c h a s thickening of the frames and removing half of the bathroom windows were done. The bathroom windows [2nd and 3rd floor] were halved and kept only as higher windows.
It func)ons as designed, and from tes)ng in model-view, blocks all direct sunlight in summer at 9:00, 12:00pm and 3:00, but allows winter light at these )mes to enter the building. Sunlight begins to penetrate the northern rooms in early April, as this is typically when autumnal season effects begin to take place in Adelaide. Entering light then begins to cut off on or around the September Equinox [Sep. 22nd]. Air Temperature: Bedroom 1st floor, Bedroom 2nd floor & Living Space Winter: Outside Dry-bulb Temperature
Summer & Winter Room Temperatures
J. Douglas-Hill
Case Study & Final Results Comparison
! !
Both these windows and the top windows on the eastern facade were modified so that they were openable. The bathroom glass was changed to sliding windows so that they were 50% openable, while the east windows could be
University of Adelaide
Case Study Summer & Winter Room Temperatures
Summer: Outside Dry-bulb Temperature
Date : January & February
Date : June, July & August
Other changes made to the building:
Date : January & February
- All walls changed to:
hinge opened by 30%. These higher hinged windows were also mirrored on the western side of the building where there was previously none. Finally, an openable skylight-vent was added to the southmost roof slope. The ground floor concrete slab w a s t h i c ke n e d t o 1 2 0 m m [ p r e v i o u s l y 1 0 0 m m ] t o experiment in heat escape minimisa)on. Finally, 6 of the windows on the 3 new windows north-face were changed to fully openable sliding windows.
- Roof cladding changed to:
reverse brick veneer consis*ng of: clay +le consis*ng of: - 8mm compressed fibre cement - 20mm thick clay )les - weatherproof membrane [CFC] cladding - )mber framing with 90mm baK - air cavity - 90mm baK insula)on insula)on - 40mm air cavity - 12.5mm plasterboard ceiling - weatherproof membrane - All glass was double-glazed with - 110mm brickwork argon fill - 12.5mm plasterboard
!
Comments These modifica)ons were very useful to the design in t h e r m a l p e r f o r m a n c e . Temperature fluctua)ons w e r e m i n i m i s e d b y a significant 6-7°C in both seasons. The reverse brick veneer, different from the tex t b o o k b r i c k ve n e e r construc)on, is designed to keep the thermal mass close to the building with exterior insula)on placed to protect it from outside condi)ons. This insula)on radiates internal temperatures back into the bricks enabling the bricks to store them.
Date : June, July & August
Comments From seeing the results, it can be deduced that these addi)ons helped enormously. The western windows were very valuable as they acted in unison with the eastern openings to allow heat to escape. This concept reflects that of the vernacular design in the tradi)onal Malay House. High slope roofs were oQen accompanied with ven)la)on joints (patah) enabling heat to rise and flow out with air currents. The addi)on of the skylight was a risk both thermally and because of its lack of shading. However, due to its placement on the southernmost slope, very liKle direct sunlight entered the top floor, making the addi)on favourable due to its capacity to directly ven)late hot rising air.
Date : January & February
Date : June, July & August
Air Temperature: Bedroom 1st floor, Bedroom 2nd floor & Living Space Winter: Outside Dry-bulb Temperature Summer: Outside Dry-bulb Temperature
Date : January & February
Final Summer & Winter Room Temperatures
Date : June, July & August