BeckryTherm — thermal control performance
A laboratory demonstration
Dark grey BeckryTherm (left) and standard coatings (right) are equally irradiated by an artificial solar lamp. This is how the panels appear in visible light:
However a thermal infrared image of the same two panels shows that the right-hand, standard, panel is much hotter:
This is confirmed by outdoor tests
The chart below shows how the interior surface of the panel is cooled as a result of using both the exterior solar reflective and the interior thermal reflective coating together.
In this set of six common roofing shades an average reduction in temperature of nearly 8°C was achieved in South Africa with BeckryTherm thermal control coatings.
| Location: |
nr. Johannesburg, RSA |
|
Panels: |
37º from horizontal |
| Latitude: |
26.6º S |
|
|
North facing |
| Longitude: |
27.9º E |
|
|
Open backed, no isolation |
| Time: |
12:05 |
|
|
| Exterior temp: |
30ºC |
|
Temperatures: |
panel interiors measured
individually using an IR pyrometer |
| Sky temp: |
-9ºC |
|
|
| Weather: |
Light breeze, clear sky |
|
|
BeckryTherm's thermal control performance compared to other coatings
BeckryTherm offers greatly improved thermal control performance compared with standard pigmentations and with spectrally-reflective ceramic colors.
The table below shows the solar reflectance of BeckryTherm (exterior with primer) compared to standard high performance polyester pigmentation and ceramic PVdF pigmentation according to ASTM E903-96 (Colour: Grey Brown RAL 8019).
| Solar reflectance |
Standard
Polyester |
Typical
ceramic pigmentations |
BeckryTherm |
| Total |
5% |
24% |
35% |
| UV |
2% |
3% |
3% |
| Visible |
4% |
4% |
4% |
| NIR |
6% |
41% |
57% |
| For this deep colour in the near infrared, BeckryTherm is nine times as reflective as standard pigmentation and 40% more reflective than ceramic
colours. |
Don’t take our word for it!
BeckryTherm’s performance has been studied and checked using a number of recognized test methods and by independent laboratories.
Measurements comparing BeckryTherm (exterior with primer) against standard pigmentations in a range of typical roofing colors for solar reflectance and IR emittance are shown below (BeckryTech binder system).
|
Colour
RAL |
Quality |
Total solar
reflectance
ASTM
E903-96
(Beckers) |
Total solar
reflectance
ASTM
E903-96
(R&D
Services*) |
Total solar
reflectance
ASTM
C1549-02
(R&D
Services*) |
Exterior IR
emittance
ASTM
C1371-98
(R&D
Services*) |
| 7040 |
BeckryTherm
Standard |
0.65
0.41 |
0.62
0.39 |
0.62
0.38 |
0.88
0.87 |
| 7015 |
BeckryTherm
Standard |
0.44
0.09 |
0.43
0.10 |
0.44
0.09 |
0.88
0.90 |
| 7021 |
BeckryTherm
Standard |
0.38
0.05 |
0.37
0.05 |
0.38
0.04 |
0.89
0.91 |
| 6014 |
BeckryTherm
Standard |
0.38
0.12 |
0.37
0.12 |
0.39
0.12 |
0.90
0.88 |
| 5008 |
BeckryTherm
Standard |
0.32
0.18 |
0.31
0.19 |
0.29
0.20 |
0.89
0.90 |
| 8012 |
BeckryTherm
Standard |
0.33
0.23 |
0.33
0.23 |
0.35
0.25 |
0.90
0.87 |
| * Accredited Independent
Testing Laboratory for Cool Roof rating. |