Adverse Conditions
Stramit® Top Hats and Battens will give excellent durability in most applications. In exposed conditions, unwashed areas subject to salt-laden air or other corrosive matter may need additional protection. Stramit® Top Hats and Battens are not recommended for use in enclosed areas within 450mm of moist soil.
Compatibility
Contact between galvanised steel and copper (e.g. pipework) must be avoided as premature corrosion will occur.
Ceiling Batten - Maximum Batten Spans (mm)
material
layers
batten centres (mm)
450
600
12mm plasterboard
1
1500
1400
12mm plasterboard
2
1250
1100
Perth Ceiling Batten - Maximum Batten Spans (mm)
material
layers
batten centres (mm)
450
600
12mm plasterboard
1
1550
1400
12mm plasterboard
2
1250
1150
Spacings
Member, fastener or roof sheeting capacity influences top hat spacing. It is often economical to reduce top hat spacing at the building edge and ends to account for the higher wind pressures encountered on these parts of the building. Additional runs may be required adjacent to roof penetrations or in areas of additional loading.
Roof batten spacings are influenced by support (truss) spacing, sheet capacity or roof tile spacing.
Ceiling batten spacing is invariably chosen to suit plasterboard manufacturer's requirements.
Laps/Ends
Lapped Stramit® Top Hat configurations require a minimum 10% lap length (i.e. 5% at each end). Section properties within the lap have been assumed to be twice that of a single section rather than the properties of a double thickness section.
End fastenings of top hats or battens are recommended to be at least 25 mm from te section end irrespective of whether this occurs at the structure end or at an internal support. The absolute minimum required by AS4600 is 1.5 df where df is the nominal screw diameter). Remember to allow for this additional material over and above the span length/s when specifying, ordering or cutting sections.
Stramit® Top Hats TH96 and TH64 have one end partially crimped to facilitate lapping.
Top hat/batten overlaps (or non-structural laps) are recommended to be 100 mm in length. In these cases structural continuity must not be assumed.
Photographs
