Hi All,

For Sky Light or Awning, use Lexan* Twin Wall, Grade Recommended is Lexan* 10mm Thickness Solar Control IR, Light Green in Color

In the 1960s, NASA used Lexan* Brand Polycarbonate for Astronaut helmet assemblies and visors which became known as "bubble helmets", including those used by the Apollo moon astronauts.



Advantages
1) 2 Wall , Better Heat Insulattion
2) Lower Cost
3) Reduce 30% Heat
4) 2 Side UV Resistant Coating ( Generally, Polycarbonate is NOT Chemical Resistant. Can be printed as label, example laptop Battery uses Polycarbonate FR Film as Label)
5) Impact Resistance. Virtually Un-Breakble Youtube has many Video on the Impact Test
6) 10 year Warranty - Against Yellowing ( yellow Index Not more than 2, which naked Eyes can see)
- Against Impact ( Drilled Holes Failure not Warrant)
- Against Lost of Light Transmission
7) Light Transmission - More than 65%,

More Details

http://en.wikipedia.org/wiki/Lexan

http://www.sabic-ip.com/sfs/SFS/en/Product...ntrolsheet.html

Dust or Fungus will grow in the Slot but that can be eliminate if you get a Good Contractor.
Use Anti - Dust tape, which will allow the Water to Vaporize and 'Flow' out through the Special Membrane in the Anti-Dust Tape
It will prevent Water from Sipping in and Grow Fungus

Many Stadium are Built from Multi-Wall Sheet , which also uses the Anti-Dust Tape
Examples :





Material Cost for Lexan* 10mm Thickness Solar Control IR, Light Green in Color is approximately RM 6.80/square feet.
Note That The Structure is more Costlier that the Roofing Material



This post has been edited by jerryng75: Jan 15 2014, 04:38 PM

Hi,

UNCOATED Polycarbonate - WEAKNESS

1) Fair Chemical Resistant ( NOT Good for Outdoor), Excellent Printability ( Examples, Washing Machine Membrane Keyboard, Microwave Labels)
2) Color Fading , due to UV Ray ( Note : UV is good for killing bacteria)
3) Breakage after prolong exposure to UV Ray
4) Dust, fungus Growth & Water in the Twin-wall Roofing, due to workmanship

Therefore, only use Coated Polycarbonate like what I'm using ( Lexan* 10mm Thickness Solar Control IR) which solve all the above 3 issues

Last problem can be solve with Breather Tape
With this you will have not water inside the Twin-wall as the membrane will allow water condensation to sip out.
Dust will not flow in as the tape will prevent it.




I'm not a contractor. Please refer to SABIC SFS

This post has been edited by jerryng75: Apr 25 2014, 06:00 PM

Hi

Check out this video to differentiate

Can you share with us which brand is it?
Is there a warranty letter from the Poly maker can download it to check?

Lonewolf

See past Post

You can Purchase ' Easy Clean ' Lexan Grade of Material. It Behaves like 'Rainex'. Rain will take the Dust along.
The limitation is , The Coating can Only last 3 Years.

Plain or Emboss is not Critical. It's the Thickness of Solid Polycarbonate that Matters.

With 6 mm Solid , It's Unbreakable with an Axe. See Video Below

Thinner than this, You skylight will be Wavy during Hot Days.
AND Solid Polycarbonate is give more Heat

Twin-Wall Will give less Heat Compare. But Need Good Contractor to prevent Dust, algae and Water in the Sheets

Dust Can be prevented with Anti-Dust.

Get Polycarbonate ( which give High Light Transmission) but Less Heat Type ( Lexan Solar Control IR).
You Check out the Sheets at Kota Kemuning , Colombia Hospital Main Entrance. Go at Noon time to feel the Heat That pass Through.