Roof Batten Spacing Calculator

A simple calculator to ensure your roof is supported and secure.

Ensure your roof has the correct batten size and spacing.

Whether for a new roof installation or repairs, knowing the correct spacing for your battens is crucial in order to make your roof structure safe and secure. Simply entering a few details will provide you with not only the correct spacing, but also the total batten length needed.

Calculate Batten Spacing

online roof batten spacing calculator

Batten Spacing: 0 mm

Total Batten Length Needed: 0 m

Calculator checked on By Jamie

Calculations Used

Roof Tiles Batten Spacing = Tile Length - Overhang - Nib Length Subtract the overhang and nib length from the tile length to determine the batten spacing.
Slate Batten Spacing = (Tile Length - Overhang) / 2 The spacing is half the length of the tile minus the overhang.
Cedar Shingles Batten Spacing = 137 mm Fixed spacing for a 45° roof.
Rosemary Roof Tiles Batten Spacing = Min(115 mm, Roof Pitch) Spacing is the minimum of 115 mm or the roof pitch.
Plain Tiles / Concrete Roof Tiles Batten Spacing = 600 mm Maximum allowable spacing.
Marley Modern Tiles Batten Spacing = 345 mm Standard spacing for Marley Modern tiles.
Redland 49 Roof Tiles Batten Spacing = Min(307 mm, Roof Pitch) Spacing is the minimum of 307 mm or the roof pitch.
Corrugated Roof Batten Spacing:
  • 1200 mm if Roof Pitch ≥ 0.7°
  • 1000 mm if Roof Pitch < 0.7°
Spacing depends on whether the roof pitch is above or below 0.7°.
Polycarbonate Roofing Batten Spacing = 800 mm Standard spacing for polycarbonate roofing.
Counter Batten Batten Spacing = 4000 mm Standard spacing for counter battens.

What are Roof Battens?

Roof battens are thin, horizontal strips of material (typically wood or metal) that are installed over the roof rafters or trusses They serve as a fixing point for roofing materials like tiles, slates, or shingles.

Battens help to evenly distribute the weight of the roofing material and provide ventilation between the roofing material and the underlying structure.

Importance of Proper Spacing

Proper batten spacing is crucial for the overall integrity of the roof. Incorrect spacing can lead to several issues, such as:

  • Poor Load Distribution: Uneven or incorrect spacing can result in localised pressure points, leading to potential damage or failure of the roofing material.
  • Water Penetration: Gaps can lead to water ingress which can damage the roof structure over time.
  • Ventilation Issues: Adequate spacing ensures proper airflow beneath the roof covering, reducing the risk of condensation and related issues like mould and rot.

Types of Roofing Materials

Roof battens can be used with a variety of roofing materials, each requiring specific spacing to ensure optimal performance and durability. The most common materials include:

  • Roof Tiles: Made from clay or concrete, these tiles are heavy and require robust batten support.
  • Slate: A natural stone option, slate is durable but requires precise batten placement.
  • Cedar Shingles: Lightweight and eco-friendly, cedar shingles are ideal for traditional homes.
  • Concrete Roof Tiles: Similar to clay tiles but heavier, requiring sturdy battens.

Material-Specific Batten Spacing

Each roofing material has unique spacing requirements:

  • Roof Tiles: Based on the tile's length, overhang, and nib length.
  • Slate: Closer batten spacing due to its thin profile.
  • Cedar Shingles: Fixed spacing, often around 137mm.
  • Concrete Roof Tiles: Wider batten spacing, around 600mm, to ensure proper load distribution.

Factors Affecting Batten Spacing

Weather Conditions

Local weather can significantly influence batten spacing. In regions with heavy snowfall, closer batten spacing may be necessary to support the additional weight. Similarly, areas prone to high winds might require more secure batten spacing to prevent uplift and damage.

Roof Design

The complexity of your roof design also has an impact:

  • Gable Roofs: Straightforward, requiring standard batten spacing.
  • Hip Roofs: More complex, might require varying batten spacing depending on the angle and layout.
  • Flat Roofs: Require careful consideration of water drainage and batten strategies.

Choosing the Right Battens

The choice of batten depends on factors such as the type of roofing material, the roof's pitch, and the environmental conditions the roof will face.

Batten Material and Quality

Choose battens that are made from high-quality, durable materials. Timber battens should be treated to resist rot and insect damage, ensuring they withstand harsh weather conditions over time. The quality of the wood is equally important; battens should be straight, free from knots, and meet the required grading standards for roofing.

Batten Dimensions

The size of the battens should correspond to the load they will bear and the type of roofing material used. For heavier materials like concrete tiles, thicker and wider battens are necessary to provide adequate support. Standard dimensions often used are 25mm x 38mm for light roofs and 25mm x 50mm for heavier materials.

Compliance with Standards

It’s crucial to ensure they comply with relevant building codes and standards, such as the BS 5534 in the UK, which outlines the specifications for roofing battens. This can be quickly identified by being either bright blue or bright red in colour.

Installation Best Practices

  • Correct Spacing: Follow the calculated spacing specific to your roofing material to ensure even load distribution.
  • Secure Fastening: Use appropriate fasteners to securely attach battens to the roof structure, preventing movement or lifting.
  • Alignment: Ensure battens are aligned properly and parallel to each other.

Common Mistakes to Avoid

  • Incorrect Spacing: Avoid using generic spacing for all materials.
  • Improper Fastening: Inadequately secured battens can lead to roof failure, especially in high-wind areas.

Maintaining and Replacing Roof Battens

Over time, exposure to the elements can cause battens to deteriorate. Regular inspections are essential to detect early signs of damage, such as rot, warping, or splitting, which could compromise the roof's stability. When inspecting, pay attention to any signs of moisture damage, particularly in areas where water might pool or where there is poor ventilation. If any battens show signs of significant wear, they should be replaced immediately to prevent further damage.

Replacement

When replacing battens, it's important to use materials that are treated for rot and insect resistance to ensure longevity.

Ensure that the replacement battens are installed again with the correct spacing and securely fastened to the roof structure. Regular maintenance not only extends the life of your roof but also prevents more costly repairs in the long term.

Frequently Asked Questions

Why is batten spacing different for various materials?

Batten spacing varies based on the weight, size, and installation method of the roofing material.

How does roof pitch affect batten spacing?

The pitch of your roof impacts water runoff and the angle at which roofing materials are installed, requiring adjustments in batten spacing to ensure proper alignment and structural integrity.

What is the standard batten spacing for roof tiles?

This depends on the tile's length and the roof's pitch, with spacing often ranging between 200mm to 350mm.

Can I use the same spacing for all roofing?

No, different roof types and materials require specific batten spacing to ensure proper support and longevity. Always calculate spacing based on the specific material and roof design.