PROGRAMME TIME
Reinforced concrete offers fast lead times. This translates into significant programme savings.
A cost model study has found that reinforced concrete can be up to 5% cheaper than steel frames for typical commercial buildings. These cost advantages were compounded by a lead time of only 4-6 weeks for reinforced concrete compared with up to 18 weeks for steel.
The study, Commercial Buildings: Cost Model Study, was carried out for The Concrete Centre by architects Allies and Morrison, structural engineers Arup and cost consultants Davis Langdon with programming carried out by Mace. The study compared the cost of constructing three- and six-storey office buildings using a variety of reinforced concrete and steel framed short and long span options.
When procurement, lead times and construction duration are taken into account - based on a 10 week procurement programme and contractor lead times of 4-6 weeks for concrete and 12-18 weeks for steel - the overall programme for the concrete framed options were shorter than for steel.
For building A, concrete with its faster start on site came in at 64-66 weeks compared to 70 weeks for steel. For Building B, concrete came in at 82-86 weeks compared to 91-93 weeks for steel. For the long span option for Building B, the overall programme time was 83 weeks for concrete and 95 weeks for steel.
“The total programme time, including lead time, is often overlooked in cost studies. This is disingenuous. For total programme time is what really matters to the bottom line”, said Elliott.
