10.00 am Sara welcomes Heather and Mitchall to Arup's offices in the West End of London. 10.30am First of all, a crash course in what "building services engineers" really do. Sara explains that what she's responsible for are the insides of buildings - the power, the water supply, the ventilation - basically everything that makes a building comfortable to be inside. Find out more here... 11.00am Once a building is under construction, Sara will don her hard hat and visit the site a couple of times a week.. but at the moment, her jobs are all in the planning stages. Heather and Mitchall are invited to sit in on a meeting with her colleague Heather Carter. They're discussing a new building project and all the steps that will have to be taken to make sure it doesn't fall behind schedule. This involves co-ordinating all the sub-contractors. What's with all the drawings? Sara and Heather constantly refer to plans and drawings as they talk about the project. Sometimes words are not enough! Sara reckons she can't discuss work without a notebook to sketch her ideas out as she speaks 12.00pm Sara demonstrates the office printer. It's set to produce A0-sized print-offs of technical drawings (ie 16x as big as a piece of A4). What's just been printed are the are drawings for each storey of a building, including the basement. Sara explains how to read the lines and symbols the professionals use. 13.00pm Time for a spot of lunch. Luckily the office is just round the corner from some groovy cafes, so soup and a sandwich is within easy reach. Better than school dinners. 14.00pm OK, your turn, guys. Sara leaves Mitchall and Heather to show their talents as the building services engineers of the future... They're shown the plan of a theatre complex Sara's worked on herself. Their challenge is to position the air handling units, which provide the ventilation to the building, into the plan. Not as easy as it might appear as there are many constraints. Verdict: "Excellent work!" says Sara, after assessing the solution they've come up with. "You've obviously understood all the issues, and you've come up with a plan for this building that would really work…" 15.30pm And here's one Sara prepared earlier! This is the brand new Greater London Authority building, now known as City Hall, designed by Norman Foster and Sara's company Arup. PS – Find out how to become a buildings services engineer? Here’s how Sara did it!