Types of concrete frame
TypeEconomic span (m)Remarks
One-way slabs4-8Economic across a wide range of spans but supporting downstand beams affect the cost, speed of construction and services distribution
Flat slabs5-9Quick and easy to construct. Often the most economic method of construction. Holes require careful detailing
Troughed slabs6-12A slightly greater structural depth, higher formwork costs and longer programme time is offset by the structure’s lighter weight, longer spans and greater adaptability
Band beam slabs8-15Useful for long spans in rectangular panels making them popular for car park construction
Two way slabs 9-12Robust construction with large span and load capacities – popular for retail premises and warehouses, but downstand beams disrupt construction and service installation
Waffle slabs 9-14 Slow to construct but useful for long spans
Precast and composite slabs 4-16Economic across a wide range of spans and loads. Increased speed and improved quality on site may be offset by long lead-in times
Post-tensioned slabs and beams 6+Insitu slabs and beams. Useful where depth is critical
Typical amount of reinforcement allowances
Suspended slabs90-135 kg/m3
Beams250-300 kg/m3
Columns200-300 kg/m3
Walls85-125 kg/m3
Concrete frame benchmarking: Residential development
Project description Base dataNo of storeysGross exterior floor area (GEFA)Cost £m/2Package value (approx)
Residential apartments (with ground floor retail area) – west London1Q019-1545,9701707,900,000
Mixed use scheme with residential apartments and basement parking – north London4Q011241,7271717,200,000
Residential apartments only – north London4Q01715,1131302,000,000
Residential apartments with private health club – south-west London4Q017-1263,3171308,300,000
Residential apartments with basement parking and retail – Glasgow1Q027-1335,8381706,300,000
Residential apartments with podium parking and retail – east London2Q021040,8801476,100,000
Typical concrete frame rates
City office£175-206 m2
Office business parks£140-160 m2
Mixed use scheme(4-11 storeys) £144-175 m2
Mixed use scheme(12-20 storeys) £130-150 m2
Typical concrete rates
Concrete mixConcrete net supply price £/m3Prelims %Overheads and profit %All in rate for a slab £/m3All in rate for a column £/m3All in rate for a beam £/m3
C35682011113118124
C40722011118123130
C50782011126131138
C60882011139144151
Typical reinforcement rates
 Labour £/tMaterial £/tWaste £/tNet cost £/tPrelims £/tOverheads and profit £/tAverage rate £/t
T16 2503752064512985859
(average bar size)
Typical formwork rates
Type of formworkCost £/m2Remarks
Soffit of slabs25-40Dependent on height, propping requirements and thickness of slabs
Permanent shuttering20-30Dependent on length and gauge of decking
Walls25-30 
Beams35-40 
Columns30-35For square/rectangular
 35-60 For circular
Specialist concrete contractors
Trade package contracts (£15m+)Annual turnover
R. O’Rourke & Sons £200m+
Byrne Bros£50m+
P.C Harrington £50m+
John Doyle Construction £50m
Trade package contracts (£8m-15m)
Mitchellson Formwork & Civil Engineering £30m
Getjar £30m
Stephenson Construction £25m
Wheelan & Grant (Contractors) £12m (Group turnover £30m)
Trade package contract (up to £8m)
C J O’Shea and Company £30m
Duffy Construction £25m
Buildstone £20m
McDermott Bros£15m
Addington (Formwork) £10m
Ascon Contracting £10m (Group turnover £380m)
A J Morrisroe & Sons £8m
Michael J Gallagher Contractors £6m
Silver Construction£0.5m