I went through alot of sites and pdf's on internet. and everywhere the calculation for number of fixtures for a given area has no factor for height of the ceiling. which means it may be calculating for a normal height, say 3-4 m.

But the problem I am facing is, I have to increase 2m of the height of the ceiling. which means the number of light fixtures should increase.

Can someone direct me to, or provide me some information.

Thank you all.