1. OTTV
FOR
NON ENGINEERS

3. OTTV
OVERALL THERMAL
TRANSFER VALUE

4. architect

5. OTTV
WATTS PER M2

6. HEAT W / m2 =
OTTV x skin area

8. architect

10. external
environment

11. Qgc
glass conduction
Qgs
glass
solar
Qwc
wall conduction

12. OTTV SOLAR CORRECTION FACTOR SHADING COEFFICIENT
Tdeq
x (1-WWR) x Uw x WWR x Uf x x WWR x DT SF CF SC
SHADING COEFFICIENT
SOLAR CORRECTION FACTOR
TEMPERATURE DIFFERENCE
DIFFERENTIAL TEMPERATURE EQUIVALENT
SOLAR FACTOR

14. SOLAR CORRECTION FACTOR SOLAR ABSORPTION FACTOR
OTTV
15 (1 −WWR) (WWR) (194 x x WWR x ) α
Uw Uf CF SC
SHADING COEFFICIENT
SOLAR CORRECTION FACTOR
SOLAR ABSORPTION FACTOR
U VALUE
BLACK
0.9 – 1.0
WHITE
0.15 – 0.3
SILVER / ALUMINIUM
0.1

15. α (1 −WWR)Uw + (WWR)Uf + ( x CF x WWR x SC)
OTTV 15
α (1 −WWR)Uw + (WWR)Uf + ( x CF x WWR x SC) 6
194
WALL HEAT
SOLAR THROUGH GLASS
WINDOW HEAT

16. Qgc Qgs 10% - 20% 80% Qwc 5% glass conduction glass solar
wall conduction 5%

17. SC
SHADING
COEFFICIENT
SC = SC1 x SC2

18. α SC U

19. OTTV IS
FOR
NON ENGINEERS

20. THANK YOU