Sloped roof or no slop, that is the question

[Jaygray]

Hi All,

I have a traditionally built 1970s extension with a cold flat roof.

I'm looking to build a new warm roof ontop of it, finished with grp. Keeping the existing 195mm birdmouth rafters.

It's currently dead flat. Should I take off the current deck and ad furing strips to give myself a 1/60 fall or should keep it the same?

My brain says ad the fall but I'm seeing a lot of new build that look to have a dead flat roof.

Any advise or tips welcomed.

 

[catlad]

If it's not a problem now, why should it be a problem in the future?

 

[Jaygray]

It's not so much "a problem" but more a question. Is it worth doing while I'm renovating the house.

 

[Tigercubrider]

I have a flat roof as well. Never actually put a level on it.
Are you sure that when it was built they didn’t put firings on it?