Increasing the Height of a Commercial Property

Hi
Im looking at adding some value to an existing industrial warehouse with an internal height of 3.6mtrs. I think if I remove the pitched roof, and install a taller flat roof would add significant value and increase its attractiveness to potential tenants.
Has anyone done this before,

 

A flat roof will still result in 3.6m clearance unless you extend the walls.

 

1) Zoning and permitted height
2) Internal size, nobody is going to install a gantry crane in a 300sqm unit etc
3) Comparable leased/for lease and is there any significant per sqm net increase for the additional height
4) ROI on cost to increase height

 

Fair bit of engineering sign-off required if building up and replacing. Is it realy worth it?

 

Yes i would hardly think it is worth it
Increase the wall height
New roof
New concrete floor to take greater load (more pallets on racking)
May as well demolish and start again

 

I have about 1.9ha of industrial buildings and have never found it worthwhile

 

Even if the current configuration isn't h&bu?