How to Back Block Plasterboard Joints

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How to Back Block Plasterboard Joints

What is Back Blocking

Block blocking is a joint reinforcing system designed to strengthen plasterboard joints, reducing deformation and preventing cracks. It serves as an essential safety measure in building structures, ensuring durability and stability to certain joints which often undergo additional stresses. These stresses include subsequent building movement, abnormal loadings due to heavy traffic, renovations where trades people are moving in ceiling spaces, and more.

Back blocking (also known as butt joints) is recommended by plasterboard manufacturers to avoid the consequential cracking of the finished jointing that often requires a call-out for warranty repair, which is an avoidable and unwanted additional cost to the contractor/builder.

Introducing the Studco B005

Studco® B005 Back Blocking Batten has been developed with the plasterboard industry and provides a consistent recess shape for the finishing of joints when installed as per the plasterboard manufacturer’s recommendation.

Back-blocking is a joint reinforcing system where Studco B005 back blocking battens are screwed behind the sheets, at certain joints which often undergo additional stresses and are therefore more vulnerable to cracking.

Back blocking is recommended by plasterboard manufacturers in accordance Australian and New Zealand Standard 2589.1. As a minimum requirement, B005’s should be used for all butt joints and in any area with 3 or more recessed joints.

The decision to back block all joints, not just the minimum requirement in the Standard, is best made by the builder after consideration of factors such as:

• Moisture content of timber.
• Maintenance history for similar installations.
• Type of roof framing and timber used.
• Severity of temperature and humidity conditions to which the installation will be subjected.

Butt Joints Installation Notes

• Butt joints which are to be back-blocked must be formed midway between framing members.
• Where mid-span butt or end joints are not required but are used to minimise plasterboard wastage, these joints must also be back-blocked.
• All mid-span joints must be positioned within 50mm of the mid-span point between the framing members.

Back-blocking is an essential process that reinforces plasterboard joints and screw fixings, providing solid support. It results in a smooth wall surface and significantly reduces the risk of cracking.

For architectural specifications or installation advice, please contact Studco Building Systems for fast, friendly service at techadvice@studcosystems.com.au or call 1300 255 255.

Studco Back Blocking Batten