Installation Instructions

28 SABIC Innovative Plastics
Installation
Installation
Glazing with Lexan Thermoclear sheet should be
considered a nishing operation and seen as the nal
step in the completion of an application.
Thermal Expansion Allowance
Since Lexan Thermoclear sheet has a greater coefcient
of linear thermal expansion than that of traditional
glazing materials, care should be taken to allow for free
expansion of the sheet to prevent bowing and internal
thermal stress.
Sheet Edge Clamping Conditions
The following recommendations apply to installations
involving both at glazing, i.e. vertical, horizontal or
inclined, and curved glazing. It is extremely important
when installing Lexan Thermoclear sheet that the edges
are correctly clamped, whether the application involves
wet or dry glazing conditions.
A cover plate, or glazing bead, with rubber gaskets or
silicone sealant, hold the sheet in place and create a
water-tight seal. In both cases there must be sufcient
clearance to allow for thermal expansion of the sheet. It
is also important that the edge of the sheet is engaged
for a minimum of 20 mm into the glazing frame with
at least one rib located in the clamping area. See g. 14
and 15.
13. This figure shows Thermal
Expansion Allowance at
various sash dimensions
14, 15. Indicates correct
#
installation when
clamping the sheet
in a profile
Allowance for thermal expansion must be made for
both the length and the width of the Lexan Thermoclear
sheet. The recommended allowances for various sheet
dimensions are outlined in the graph.
The sheet must be trimmed to allow for at least as
much as the indicated thermal expansion.
In general: Thermal expansion of the sheet is
approximately 3 mm per linear metre
at a delta of 50°C.
In general the total rebate depth for each prole should
include a minimum of 20 mm sheet edge engagement
and an allowance for thermal expansion.
#
Due to the rib geometry of Lexan Thermoclear sheet, at a
thickness of ≥16 mm, additional precautions should be taken.
In this case it is important that the sheet is cut such that at least
one rib is located in the centre of the rebate.
Sash dimension in mm
Total thermal expansion in mm
500 1000 1500 2000 2500 3000 3500 4000 4500 5000
0
1
2
3
4
5
6
8
10
12
7
9
11
13
14
15
13
14
sheet edge
engagement ± 20 mm
15