" This research verified that any of the three clay brick walling formats provide property owners and residents with lowest energy usage and hence greatest thermal comfort ."
COVER STORY
Table 1 : Annual energy usage – 40m 2 affordable house |
|
|
|
|
|
GT |
KZN |
WC |
FS |
LM |
NC |
280mm cavity clay brick with insulation |
379 |
296 |
218 |
496 |
2 |
1 244 |
270mm cavity clay brick |
725 |
454 |
479 |
1 009 |
887 |
1 904 |
220mm clay brick |
1 055 |
590 |
734 |
1 464 |
1 282 |
2 428 |
Light steel frame ( SABS 517 ) |
1 082 |
827 |
868 |
945 |
1 135 |
2 054 |
Timber frame ( SABS 10 082 ) |
1 066 |
786 |
862 |
1 012 |
853 |
1 953 |
140mm hollow concrete block |
1 505 |
749 |
1 079 |
2 164 |
1 623 |
3 087 |
Table 2 : Thermal transmittance ( U-Values ) of walling systems
WALLING SYSTEM THERMAL TRANSMITTANCE ( W / m 2 K )
CLIMATE ZONES 1 AND 6
CLIMATE ZONES 2 , 3 , 4 AND 5
140mm hollow concrete block 3.17 3.17 220mm solid clay brick masonry 2.22 2.22 270mm cavity clay brick masonry 1.66 1.66 280mm cavity clay brick masonry insulated 0.80 0.80 Timber frame to SANS 204 0.75 0.80 Light steel frame to SANS 204 0.67 0.77
U-Value – long considered to be a good measurement of energy efficiency – has little correlation with energy use and electricity cost savings . Energy use does appear to correlate with material density .
CONCLUSION
“ Members of the Clay Brick Association ( CBA ) of Southern Africa are pleased to see that the study corroborates existing national and international research for clay brick products ,” says CBA executive director Jonathan Prior . “ This research verified that any of the three clay brick walling formats provide property owners and residents with lowest energy usage and hence greatest thermal comfort .”
“ This also shows the value of thermal insulation for residential buildings ,” comments CBA technical director , Nico Mienie . “ It points to the need for changes in the SA building regulations to relook at the thermal resistance and heat bridging requirements of SANS 517 and SANS 10082 .”
“ Thanks to this study , architects and public and private sector developers are able to make more informed decisions about future walling specifications ,” Mienie concludes . “ This will protect South Africa ’ s environment and give rise to high performance structures that reduce our reliance on electricity .”
" This research verified that any of the three clay brick walling formats provide property owners and residents with lowest energy usage and hence greatest thermal comfort ."
* Prepared by the Department of Architecture , University of Pretoria . Authors : G Rice ( Researcher ), P Vosloo , H Harris , D Holm , N van Rooyen . The authors and any participants in this study cannot be held liable for any claim of damages of any nature whatsoever , arising from this study .
FOR MORE INFORMATION :
The Clay Brick Association of South Africa Website : www . claybrick . org
THE VOICE OF THE CLAY BRICK INDUSTRY
16
JANUARY - FEBRUARY 2017
AFFORDABLE
SA HOUSING