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Formwork (shuttering) in concrete construction is used as a mould for a structure in which fresh concrete is poured only to harden subsequently. Types of concrete formwork construction depends on formwork material and type of structural element.

Formworks can also be named based on the type of structural member construction such as slab formwork for use in slab, beam formwork, column formwork for use in beams and columns respectively etc.

The construction of formwork takes time and involves expenditure upto 20 to 25% of the cost of the structure or even more. Design of these temporary structures are made to economic expenditure. The operation of removing the formwork is known as stripping. Stripped formwork can be reused. Reusable forms are known as panel forms and non-usable are called stationary forms.

Timber is the most common material used for formwork. The disadvantage with timber formwork is that it will warp, swell and shrink. Application of water impermeable cost to the surface of wood mitigates these defects.

A good formwork should satisfy the following requirements:

  1. It should be strong enough to withstand all types of dead and live loads.
  2. It should be rigidly constructed and efficiently propped and braced both horizontally and vertically, so as to retain its shape.
  3. The joints in the formwork should be tight against leakage of cement grout.
  4. Construction of formwork should permit removal of various parts in desired sequences without damage to the concrete.
  5. The material of the formwork should be cheap, easily available and should be suitable for reuse.
  6. The formwork should be set accurately to the desired line and levels should have plane surface.
  7. It should be as light as possible.
  8. The material of the formwork should not warp or get distorted when exposed to the elements.
  9. It should rest on firm base.

Economy in Formwork

The following points are to be kept in view to effect economy in the cost of formwork:

  1. The plan of the building should imply minimum number of variations in the size of rooms, floor area etc. so as to permit reuse of the formwork repeatedly.
  2. Design should be perfect to use slender sections only in a most economical way.
  3. Minimum sawing and cutting of wooden pieces should be made to enable reuse of the material a number of times. The quantity of surface finish depends on the quality of the formwork.

Formwork can be made out of timber, plywood, steel, precast concrete or fiberglass used separately or in combination. Steel forms are used in situation where large numbers of re-use of the same forms are necessary. For small works, timber formwork proves useful. Fibre glass made of precast concrete and aluminium are used in cast-in-situ construction such as slabs or members involving curved surfaces.

Types of Formwork (Shuttering) for Concrete Construction:

Timber Formwork:

Timber for formwork should satisfy the following requirement:

It should be

  1. well seasoned
  2. light in weight
  3. easily workable with nails without splitting
  4. free from loose knots

Timber used for shuttering for exposed concrete work should have smooth and even surface on all faces which come in contact with concrete.

Normal sizes of members for timber formwork:

Sheeting for slabs, beam, column side and beam bottom25 mm to 40mm thick
Joints, ledges50 x 70 mm to 50 x 150 mm
Posts75 x 100mm to 100 x 100 mm

Plywood Formwork

Resin bonded plywood sheets are attached to timber frames to make up panels of required sizes. The cost of plywood formwork compares favourably with that of timber shuttering and it may even prove cheaper in certain cases in view of the following considerations:

  1. It is possible to have smooth finish in which case on cost in surface finishing is there.
  2. By use of large size panels it is possible to effect saving in the labour cost of fixing and dismantling.
  3. Number of reuses are more as compared with timber shuttering. For estimation purpose, number of reuses can be taken as 20 to 25.

Steel Formwork

This consist of panels fabricated out of thin steel plates stiffened along the edges by small steel angles. The panel units can be held together through the use of suitable clamps or bolts and nuts. The panels can be fabricated in large number in any desired modular shape or size. Steel forms are largely used in large projects or in situation where large number reuses of the shuttering is possible. This type of shuttering is considered most suitable for circular or curved structures.

Steel forms compared with timber formwork:

  1. Steel forms are stronger, durable and have longer life than timber formwork and their reuses are more in number.
  2. Steel forms can be installed and dismantled with greater ease and speed.
  3. The quality of exposed concrete surface by using steel forms is good and such surfaces need no further treatment.
  4. Steel formwork does not absorb moisture from concrete.
  5. Steel formwork does not shrink or warp.

Construction of Concrete formwork:

This normally involves the following operations:

  1. Propping and centring
  2. Shuttering
  3. Provision of camber
  4. Cleaning and surface treatment

Order and Method of Removing Formwork:

The sequence of orders and method of removal of formwork are as follows:

  1. Shuttering forming the vertical faces of walls, beams and column sides should be removed first as they bear no load but only retain the concrete.
  2. Shuttering forming soffit of slabs should be removed next.
  3. Shuttering forming soffit of beams, girders or other heavily loaded shuttering should be removed in the end.

Rapid hardening cement, warm weather and light loading conditions allow early removal of formwork. The formwork should under no circumstances be allowed to be removed until all the concrete reaches strength of atleast twice the stresses to which the concrete may be subjected at the time of removal of formwork. All formworks should be eased gradually and carefully in order to prevent the load being suddenly transferred to concrete.

Figure 1 to 6 shows formwork for different types of members in civil engineering construction.

Types of formwork - Details of timber formwork for RCC beam and slab floor

Figure 1(a): Details of timber formwork for RCC beam and slab floor

Details of timber formwork for RCC beam and slab floor

Figure 1(b): Details at section (A) shown in above figure

Details of timber formwork for circular RCC column

Figure 2(a): Elevation

Details of timber formwork for circular RCC column

Figure 2(b): Details of timber formwork for circular RCC column

Details of timber formwork for square or rectangular RCC column

Figure 3(a): 150 3D View

Details of timber formwork for square or rectangular RCC column

Figure 3(b): Details of timber formwork for square or rectangular RCC column

Sectional plan showing details of timber formwork for an octagonal column

Figure 4: Sectional plan showing details of timber formwork for an octagonal column

Details of formwork for stair

Figure 5: Details of formwork for stair

Timber formwork for RCC wall

Figure 6: Timber formwork for RCC wall

Table: Period of Removal of Formwork

S. No.Description of structural memberTime Period
1Walls, columns and vertical sides of beams1 to 2 days
2Slabs (props left under)3 days
3Beam soffits (props left under)7 days
4Removal of props to slabs
(a) For slabs spanning upto 4.5 m7 days
(b) For slabs spanning over 4.5 m14 days
5Removal of props to beams and arches
(a) Spanning upto 6 m14 days
(b) spanning over 6 m21 days

Read More:

Plastic Formworks for Concrete – Applications and Advantages in Construction

Wooden Concrete Formwork Design Criteria with Calculation Formulas

Concrete Formwork Loads and Pressure Calculations

Formwork Removal Time & Specifications

Measurement of Formworks

Formwork (Shuttering) for Different Structural Members -Beams, Slabs etc

Formwork Safe Practices Checklist

About Gopal MishraVerified

Gopal Mishra is a Civil Engineer from NIT Calicut and has more than 10 years of experience in Civil Engineering and Construction. He is the founder of The Constructor.

Comments ( 106 )

  1. good work formwork

  2. Nice & technically helpful..thanks to the author.

  3. Hunadi Ntsoane
    Aug 9, 2014 at 20:42

    usefull info

  4. Hunadi Ntsoane
    Aug 9, 2014 at 20:42

    usefull info

  5. Saurabh Ganeshkar
    Jul 20, 2014 at 07:20

    thanks for that information this is very useful to us

  6. Sachini Rathnayaka
    Jul 8, 2014 at 05:44

    thanks for information

  7. nice ……….

  8. helpful for upgrading knowledge

  9. Good information and helpful

  10. good information

  11. here no spacing given in between yoke, batten,

  12. please make sure be safe always in construction sit

  13. useful information. thanks

  14. Thanks but what about concreting

  15. Thanks but what about concreting

  16. i need a job if usomeone help me [email protected] is my id so contact me plzzzzzzzz

  17. very nice for information to a civil engineer

  18. Who has timber form design for pile cap

  19. THANX FOR GOOD INFORMATION FOR CONSTRUCTION

  20. Thank for good explanation.

  21. thanks inf. indeed.

  22. you guys are strait and accurate!

  23. thank you very much it,s help me a lot……….

  24. Mzilethi Khelele
    Jan 30, 2014 at 16:05

    THANK YOU FOR THE INFOR

  25. Straight to the point……thank you

  26. thanks all workers were waiting for instructions

  27. so usefukll thx a lot for this articl

  28. incredible material.thanks civil eng.

  29. Made engineering world easy

  30. very good thought for improve and short time learing thanku

  31. anything else thats economical to supplement timber

  32. perfact design of wooden shuttering

  33. Arianne Punzalan, " Low cost housing" after earthquack diaster.

  34. The above information is very good but valuable to the beginners. If you can take the details to the depth, our community will take the benefit.
    If you can discuss the details of Plastic and Aluminum form work, the economy in the number of turns would benefit the construction field as a whole.

  35. Arianne,

    If you want to take an innovative study, please consider the following fields.
    1. Foundations – Our foundation cost on any structure is very high. Take a study and compare with one another and deliver a paper that the one which is economical.

    2. We are spending more on Form works. Take a study on different form works being used. Aluminum and Plastic form works are out in the market for commercial use. I understand from my experience, the plastic forms are efficient in handling, increase the out put and the number of turns is from 40 to 50 times, whereas wood is very costly. Your technical paper will get appreciation.

    Many more are there on the list.

    Try these two first and see your out put.

    Regards,
    Janardhanan
    Qatar

  36. wonderful presentation but need more information about steel structures

  37. I am into a Timber Formwork with encapsulated High Density Thermocol – the Thermocol is not removed and stays in place to provide Thermal Insulation

  38. Thanks for the useful information, we are manufacturing plasticformwork, if someone wants to have more information. plz sendcur enqry to [email protected]

  39. more study fiber form work shuttering

  40. Er Niraj Kumar after 7 days v shld get 70% of the strength.

  41. Prince Jacob is there any way to check the supports? that what i meant

  42. Check for level,sides,etc are there

  43. can u plz tell what all tests are there to check the quality of formwork.

  44. Sunil Sr Frankly Don
    Sep 22, 2013 at 04:08

    really good

  45. nice

  46. Baracka Biswalo Matthew
    Sep 11, 2013 at 16:18

    ts great

  47. Vinula Rehan Dias
    Sep 8, 2013 at 12:24

    great help………………. Thanx….

  48. Lakmina Vishodana
    Sep 2, 2013 at 05:19

    thanks for this info service.

  49. very helpful…

  50. sir can you tell me how to calculate shuttering materials all

  51. I would be grateful if your technical study took into account the possibility of use of: stone (basalt), raw land and insulating materials entirely organic. Thanks

  52. nice article, thanks n good job.

  53. its gud

  54. good day sir/madam, Thank you very much.

  55. how to build timber form work.

  56. Attn! Attn! attn! everyone………
    we r the manufractures of steel scaffolding & formworks products. we r JVR FORGINGS LTD.Everyone who have required pls contct me. Rishi Singh or [email protected].

  57. Thanks for good article it is very usful.

  58. thank you for this information!

  59. Arianne – have a look at what moladi does – Reusable plastic formwork http://moladi.blogspot.com

  60. Thank you for this info – maybe you can compile an article on moladi plastic formwork – http://www.moladi.net.

  61. Nice article. Specially shutter opening table is very helpfull.

  62. Er Niraj Kumar . Steel is the heart of the construction. so, learn how the steel is designed for the building as per S.B.C.(soil capacity) and give quantities of steel in columns, beams and slabs water tanks and checking .

  63. there is a lot of new information that I got. thanks alot

  64. thanks for the informations…

  65. dear can u innovate leveling machine for slab checking without needing leveling just install it and ready to use

  66. Dear Mr.Gopal, I am Rajesh from Sri Raam Traders,Tamil Nadu.I am one of the leading Building Construction MatConterial supplier in my city.And also young growing builder.Basically i have a 3 years experience in Construction field.Last May i was started a New Residance contract work.i have a lot of suggestion in this work.

    I wil send my plan to ur mail.so plsend me email id to my mail.i will send all the details to u.

    Thanks & Regards,

    Rajesh.

  67. cn newe1 plzzzzzz tel me abt a site 4m wer I cn download my projcts………

  68. hello, Arianne Punzalan
    the main thing is in the field of construction is CONCRETE TECHNOLOGY.

  69. feasibility study of what?

  70. Benjamin Kardel
    Nov 19, 2011 at 20:08

    Hi Gopal Mishra.I'm Benjamin Kardel from VietNam.I'm interested in Construction field.your blog containt many posting which are interested.May I copy these post and Links to my Blog? Tks you.
    My blog at: http://www.construction-site-vn.blogspot.com.
    Nice to meet you.

    • Hi Benjamin,
      you can not copy complete post and put in your blog, but you can copy 2-3 lines, like an abstract and post in your blog with a link to the original post on the constructor.

  71. I would like to learn all types of form work methods and designs kindly provide the information about the new methods & demos to improve my knowledge in my construction proffession.Regards,Rajendra.

  72. steel,wood form work

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