09 Feb 2026

Trevor's Compliance Tips

In our series of articles, our Technical Compliance Manager, Trevor Atkinson, will highlight some of the most common technical non-compliances identified during inspections and provide practical guidance to help you get it right first time. We’re kicking off the series with a focus on batten installation, sharing key tips on how to avoid issues and ensure your work meets the required standards during CPS inspections.

Batten Installation

As inspectors for the NFRC Competent Person Scheme, we regularly see the same non-compliance issues arise when we inspect batten installations. CPS inspectors follow the British Standard (BS5534) to assess batten installation compliance. This standard is available to buy from the NFRC website, or freely accessible for existing NFRC members.

Typical non-compliance issues with batten installations

The most common non-compliance issues we see with batten installations are:

battens are too short
incorrect nail types/sizes are used
joints are lining up on the same rafter
cuts are made off-centre from rafter
inadequate or missing markings of battens.

The remainder of this article will provide simple guidance to ensure your batten installation can pass a Competent Person Scheme inspection.

Top tips to ensure your batten installation will pass a CPS inspection

Batten type and marking

Aequate marking is essential to ensure traceability and to confirm battens meet strength and grading requirements. Each batten must be clearly and indelibly marked to show:

Supper name
Origin/ timber species
Grade (to BS 5534)
Size

Batten fixings

Acceptable fixings include:

Galvanised or sherardized smooth round nails
Annual ring shank or helical shank (threaded) nails

Minimum nail size:

Hand nailing 65mm x 3.35mm
Nail gun: 63mm x 3.1mm galvanised ring shank
- head must finish flush with batten surface

Tip from Trevor: Remember that fixing resistance to wind uplift must comply with BS 5534.

Batten installation

battens must span at least 3 rafters
minimum batten length: 1200mm where practical
All cuts should be square, made on the centre of the rafter
Ends must be splay-nailed into the rafter.

Tip from Trevor: Measure batten layouts before cutting, to reduce waste and maintain consistent gauge.

Batten sizes

Batten sizes (typical application)

Application	Rafter Centres	Minimum Batten Size	Recommended Practice
Single lap tiles	≥ 450mm	38 x 25mm	Prefer 50 x 25mm regardles of rafter spacing
Double lap tiles	Any	38 x 25mm
Natural slate	Any	50 x 25mm

Batten Staggering (joint limits)

To maintain structural integrity and load distribution:

Batten Gauge	Max. Joints on Same Rafter
> 200mm	1 joint on 4 consecutive battens
< 200mm	3 joints in 12 consecutive battens

Keep this information handy next time you're installing battens to ensure that your work stays compliant. Look out for more of Trevor's Compliance Tips coming soon!