Boards to protect flat roof

[Drdub]

Hi

I'm about to paint the exterior wall and window frames of a bedroom and bathroom at the back of my house. Because these rooms are above a flat roof extension, I have to put my step-ladder onto the flat roof. It's a felt-covered roof and I want put down some boarding to protect the area where where the ladder will be.

What's the best cost-effective type of boarding to use? Thanks.

 

[Deleted member 174758]

OSB 11mm. We use it a lot for protection

 

[Drdub]

Thanks for the tip.

 

[Deleted member 174758]

Just double it up if it is on softer surfaces such as grass (or go to 18mm)