Calculation of the required area

Dear all, We are doing a project with an IT office complex. The largest possible waste stream is E-Waste, food and paper. We do not see much potential for glass and metal waste streams. So we are thinking of eliminating those insignificant waste streams in our calculation to estimate the required waste storage area and add E-Waste and Food waste streams in to the equation. In doing so we calculated a worst case scenario of about 5 tons of waste per month. And now we have a challenge of converting this waste amount in to floor area requirement. Q1: Please give your comments on our approach that I have described above. Do you think we are thinking correctly on this matter? Q2: Please give your advise on converting the waste quantities to required storage space (area). Is there any rules of thumbs or standards for this? Thank you!