The second permanent under secretary for defence told the conference that while there was a pressure on all Government divisions to reduce the size of their estate, the MoD would be spending £8 billion on construction and property maintenance over the next four years.
He warned that less would be invested in new build and there would be a push on the sustainability of the department’s already-established assets. The MoD’s civil estate is currently valued at some £30 billion.
Sir Andrews said: "The nature of our demands is changing and it’s changing fast.
"There are great pressures for a lesser carbon footprint. We will need government supply chains that are increasingly sustainable – that is a message I suggest for all of you. So start thinking outside the box as to what this means for you."
The MoD released its sustainable procurement action plan late last year and a charter is expected to be signed by ministers later this month.
Housing minister Caroline Flint escaped questions at the industry summit when a vote on counter-terrorism measures in the House of Commons cut her speech short.
She did, however, spend her brief appearance thanking the industry for its support and encouraging anxious individuals to speak to her regarding issues within the troubled sector.
Mrs Flint said: "I can make a promise to you that I will always have an open door to listen to your concerns."