How to represent "Buffer" on BigPicture?

[Bastien Delourmel]

Good morning, 

We are using bigpicture for project activites, scheduling, managing resourcing etc..

For the scheduling we would like to use buffer on the planning. 

What would be the best practice(s) in BigPicture to include buffer? I didn't find any documentation on BigPicture support, I may haven't searched well.

Thanks a lot!