Battens

Battens may be required to provide  create a speparation space between roofing and underlay. In some applications, they may need to be ventilated to achieve sufficient airflow.

The type and number of fixings required to fix the counter battens to the roof structure must meet the design wind load, or the roof fasteners should be long enough to achieve the required penetration into the purlin below.

Battens or counter battens, if not fixed by extended cladding fasteners, can be fixed using countersunk purlin screws or if fixed with hex headed screws, they should be counter-bored before installation to avoid damage to the roof cladding.

Steel top hat, C or Z sections are also used as counter battens but require an additional insulating spacer to avoid thermal bridging.

Using Z Counter Battens with Insulating Spacers

Zed Counter batten.svg

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