TECHNICAL INFORMATION

FIRE
The thermoplastic glazing materials have been tested in accordance with the relevant British Standards with the following results:

TEST
POLYCARBONATE
STANDARD ACRYLIC
PVCu

BS 2782: 1970
Method 508 A
Flame retartant
Not flame retardant
Flame retardant
BS 2782: 1970
Method 508 D
Very low flammability
Flammable
Very low flammability
BS 476: Part 7: 1971
Surface spread of flame (or 1987)
* Class 1
(see note)
* Class 3
* Class 1
BS 476: Part 8: 1972
Fire resistance of elements of building construction
** Less than 1/2 hour
** Less than 1/2 hour
** Less than 1/2 hour
BS 476: Part 3: 1958
External fire exposure roof tests
AA
DDX
Not applicable
Building Reg.
Appendix A
Approved Document B
TP(a)*
TP(b)*
TP(a)*

* when tested in 3mm thickness and over
** Assumed results
Note: Materials which achieve class IY can be regarded as having an AA
designation

WEIGHT
POLYCARBONATE 3mm - 4.5kg/m2
PVCu 3mm - 4.5kg/m2

RELATIVE IMPACT & BREAKAGE RESISTANCE
6mm Georgian Wired Glass
3mm PVCu - approximately 50 times stronger than the glass
3mm Polycarbonate - unbreakable within the limits of the test comparison

THERMAL TRANSMISSION (U Value)
POLYCARBONATE
 Single Skin - 3mm 5.4w/m2/degree C
Double Skin - 3mm 2.6w/m2/degree C


LIGHT TRANSMISSION (BASED ON 3mm)
POLYCARBONATE
clear - approximately 82%
opal - approximately 50%

PVCu
clear - approximately 85%
opal - approximately 72%

CAST ACRYLIC
clear - approximately 92%
opal - approximately 78%

All Astrofade rooflights can be supplied in bronze to control solar gain and glare

MATERIAL
LIGHT TRANSMISSION
TOTAL SOLAR ENERGY TRANSMISSION
Bronze Polycarbonate
50%
55%
Bronze PVCu
60%
69%