ᐅ Making a cold roof with OSB walkable – which battens to use as a sub-batten?

Hello everyone,

we are planning to equip our cold roof with a subfloor made of OSB boards to use it as storage space. We have been advised to install counter battens on the rafters to improve air circulation in the insulation between the rafters.

Could someone give us advice on which dimensions the battens should have? 28x48mm (1.1x1.9 inches), 40x60mm (1.6x2.4 inches), ...?

Many thanks in advance!

My current advice: Take whatever you can get 😉 A 2cm (1 inch) gap from the insulation is sufficient for air circulation. In practice, this will likely be inexpensive roof battens measuring 3x4cm (1.2x1.6 inches). With 15mm (0.6 inch) thick OSB, a practical batten spacing is about 40cm (16 inches).

You’re right... better act fast while there’s still some left 😉

And in your opinion, what should the spacing be for 25mm (1 inch) boards?

Nail the tongue-and-groove boards on directly, without counter battens. This allows some air to reach the insulation. It's also easier than working with the panels.

Create a gap to the insulation and use tongue-and-groove boards

Unfortunately, the panels are already on site 😎