Floor Deck Sheet

Flordec Sheets

The floor is constituted by a profiled sheet onto which a layer of concrete is poured. The sheet is bonded to the concrete by means of mouldings on the sheet which stop the concrete from slipping horizontally and detaching vertically. When the concrete is poured and until it has reached an appropriate level of hardening.

(stage 1), the weights of the concrete, personnel working and equipment used in borne by the sheet alone. Once the concrete has hardened .

(stage 2) the sheet and the concrete form a unified bond with all the Characteristics of traditional reinforced concrete, where the sheet, after having performed the function of framework, acts as a metal reinforcement. Appropriate crop ends must be provided to absorb the negative moments.

Decking Profile 75 / 305mm

  • Reduced Concrete usage : Tensile steel for composite slab construction that cuts down on slab thickness and dead weight of buildings. Providing a more sustainable solution and reducing costs.
  • No separate formwork required for slab casting.
  • Reduces construction time.
  • Technical department at Alfa offers comprahassive advisory of service on design of composite flooring should quiries arise when are not cover by this literature please contact us.

Base Metal

  • High tensile structural grade steel
  • Coating Mass 120, 180 & 275 GSM
  • Coating Standard IS : 277
  • Yield Strength 240 MPA / 350 MPA / 550 MPA
  • Premier Coating Minimum 10 Microns
  • Colour coating Premier 10 Microns Bottom 25 Micron

Available Finish

  • Cold Rolled (CR)
  • Pre coated galvanized under side giving durable and attractive appearance and minimum future maintenance. Thickness 0.8mm/1mm/1.2m
Panel Thickness Design Thickness Profile Weight Area of Steel Height of neutral axis Moment pof Lnertia Moment of carying capacity
Sagging Hogging
mm mm kg.m2 cm2 mm cm4 KN.m/m KN.m/m
0.8 0.77 7.66 9.76 37.80 100.90 4.004 3.983
1.0 0.97 9.57 12.19 38.12 126.10 4.993 4.962
1.2 1.17 11.97 15.25 38.28 157.70 6.230 6.179
fy= 25 Kn/cm2
E= 2.00E+08 KN/M2
Maximum span (double span) (in meters)
Panel Thickness Profile Weight Sectional Area Concrete slab depth above profile
mm kg/m2 cm2 100mm 150mm 200mm 250mm
0.80 7.66 9.76 2.90 2.50 2.30 2.000
1.00 9.57 12.19 3.30 2.80 2.50 2.300
1.20 11.97 15.25 3.70 3.20 2.80 2.600

Deck Sheet For Car Park

Uniquely for a composite floor profile

Alfa Deck Sheet 75 can be manufactured with pre-finished steel coating to the underside. This is suitable for situations where a visibly exposed soffit is required, such as in multi-storey car parks. The Alfa soffit can be left exposed or where further protection is required it can form the base coat for further protective systems

No Typical Properties Test Specification Test Values
1 Nominal coating thickness ECCA T1 25 microns
2 Gloss (600) ECCA T2 25-45%
3 Pencil hardness ECCA T4 2H
4 Flexibility
Reverse Impact
Minimum Bend
4T diameter, 2T radius
5 Adhesion
Cross Hatch
BS 3900/E2 100%
6 Corrosion resistance
Salt Spray
UV resistance (QUV-A)
BS 3900/F2
Galvatite® 500 hrs
Galvatite® 1000 hrs
Very good
7 Abrasion resistance (Taber) *1 ASTM D4060 <40mg
8 Scratch resistance BS 3900/E2 2500mg
9 Maximum continuous operating temperature 120ºC
10 Minimum forming temperature 20ºC
11 Surface spread of flame BS 476 Part 7 Class 1


The Alfa soffit is manufactured using Exterior Flexible Polyester pre-finished steel. The product has good formability and durability in exterior application. It has a Galvanised substrate to BS EN 10326 with a zinc metallic coating offering good corrosion resistance.

An overall prediction of soffit performance in a semi-external environment is not possible due to the variation in conditions that inevitably apply to different applications.

The 25 micron polyester coating on its own will be satisfactory in a dry and unpolluted environment (such as would be expected on most car park soffits) and will only require regular inspection or assessment after a period of ten years.

Use of (pre-finished) steel decking with composite beams

Through deck welded shear studs cannot be used with pre-finished deck, however various alternative options are available.

  • Use shear connectors that are attached to the beams without the need for welding. A number of connectors that use shot-fired pins are available.
  • Weld the studs to the beams in the fabrication shop, prior to applying the corrosion protection. With this solution the decking is laid in single span lengths and butted up to the studs.
  • Use non-composite beams.
  • Use a combination of non-composite secondary beams and composite primary beams. The decking can then be laid in continuous lengths across the secondary beams, which are normal to the span of the primary beams.


Deck Sheet in Car Parks

Composite floor decking offers the same benefits to car parks as to other steel framed buildings. Primarily these are speed of erection and reduced carriage requirements. Furthermore the reduced structure weight, height, and the provision of a working platform during construction can be very significant advantages.

Durability of metal decking in car parks

Galvanised is the standard protective coating for composite steel decking, giving a sufficient level of corrosion protection to the upper surface of the decking, provided adequate provision has been made to prevent the ingress of water (using reinforcement to control cracking, and waterproofing to the top surface of the concrete). The top deck of the car park should be waterproofed with a traditional bituminous membrane or liquid applied seamless coating. It is also good practice to treat other floors to prevent ingress of water from above. Adequate falls and drainage should be provided, to prevent the build up of water on the slabs.

The underside of the decking may additionally be pre-finished (such as Alfa with Colorcoat Exterior Flexible Polyester) or by using epoxy paint applied in situ, in order to provide a contemporary appeal or additional protection. Corus will provide advice on durability or future maintenance depending on the preferred post-finish.

Car park roof

Car parks, but more importantly their users, will benefit from protection against the external climate.

There is a growing trend to use a lightweight roof over the top parking deck. This gives added protection to the top floor of the car park allowing users to park in all weathers. The aesthetic appeal of a car park can be significantly enhanced by this method enabling the car park to blend in with the urban environment. The long-term benefits of reduced maintenance can far outweigh the initial cost of this approach.

Send Us Enquiry