Concrete Formwork Removal Times: When and How to Remove Concrete Forms

When to Remove Concrete Forms?

Concrete forms are steel or aluminum mould in which concrete is poured to manufacture many structures like columns, slabs, beams, and many other types of cement structures. It is an alternative method of an old type of timber shuttering. To reduce the construction cost the steel or aluminum types of mould are used.

If it has under proper maintenance then it can be reused as many as 2000 times. The forms can be removed after when the concrete is properly hardened in to the mould. This process is called stripping or shuttering. The form removal time is different with different types of cement.

For walls and columns, the removal time forms are 24 to 48 hours. With their props left the forms of the slab can be removed after 3 to 4 days. With their props left the soffits can be removed after one week. Over fifteen feet slab with props support can be removed after two weeks. Less than fifteen feet slab with props support can be removed after one week.

With props supporting beams and arches less than 20 feet can be removed after 2 weeks. With props supporting beams and arches over 20 feet can be removed after 2 weeks.

Concrete Formwork Removal Time:

The formwork can be removed after when the concrete is properly hardened in to the mould. The mould should be steel or aluminum or wood. The formwork removal time is different with different types of cement.

#1. Formwork Removal Time with Ordinary Portland Cement.

1. The formwork removal time of beams, columns, and walls are 2 to 3 days.
2. The formwork removal time of slabs is 3 days.
3. The slab shuttering is completely removed after 10 days.
4. In 8 days beam removal of sheeting required.
5. With props supporting beams and arches less than 20 feet can be removed after two weeks.
6. With props supporting beams and arches over 20 feet can be removed after two weeks.

#2. Formwork Removal Time with Rapid Hardening Cement.

1. In rapid hardening cement, the slab shuttering completely can be removed after 5 days.
2. In this cement the walls, columns, and beams formwork removed after 2 days.
3. In this rapid hardening cement the slab sides required 3 days.
4. In this rapid hardening cement beams removal of sheeting required 5 days.
5. The rapid hardening cement the beams and arches complete removal of shuttering required 5 to 8 days.
6. The shuttering removals time should be 8 to 10 days if the span of a beam and arches is more than 6 meters.

Earliest Time to Remove Concrete Forms:

To remove early the concrete forms have high risk. But in business, everyone wants to gate profit for this to know the short time to need hardening the concrete and gain the strength some mechanical process is used. The form removal time is different with different types of cement. Which is as follows.

1. By removing forms at any given age was similar for plastic faced plywood the probability of causing damage to concrete.
2. For walls and columns, the removal time forms are 24 to 48 hours.
3. With their props left the forms of the slab can be removed after 3 to 4 days.
4. After the curing period equivalent to 12 hours the concrete attained an in-place strength of 290 psi as measured by cubes. It was concluded that for exposed high-quality work the plywood can be removed.
5. With their props left the soffits can be removed after one week.
6. Over fifteen feet slab with props support can be removed after two weeks.
7. Less than fifteen feet slab with props support can be removed after one week.
8. To props supporting beams and arches less than twenty feet can be removed after two weeks.
9. To props supporting beams and arches over twenty feet can be removed after two weeks.
10. With the releasing agent, the plywood is treated.
11. At last the deshuttering time is varies to varies with cement-like from the ordinary portland cement to the rapid hardening cement takes less time in setting.

How Long Before Removing Concrete Forms?

1. For Concrete Forms, Concrete walls and concrete columns can be removed after about 24 to 48 hours.
2. Slabs, with their support left under them, can be normally removed after 3 to 4 days.
3. The Soffits, with their remaining supports under them, can be removed after 1 week.
4. Concrete Forms supporting slabs of less than 15 meters can be removed after 1 week.
5. Concrete Forms supporting slabs over 15 meters can be removed after 2 weeks.
6. Concrete Forms to support the beams and arches of less than 20 feet can be removed in 2 weeks.
7. Concrete Forms to support beams and arches of more than 20 meters can be removed after 3 weeks.
8. If the engineers use Portland Pozzolana Cement (PPC), the time before the form is removed is 10/7 of the above times.

When to Remove Forms From Concrete Slab?

1. The forms from Concrete Slab should only be removed when the concrete has hardened to the point where it can support its load and the loads placed on it, otherwise, it may change or fall without support.
2. If you are pouring concrete for a driveway, wall or other home improvement project, the form is usually required to hold the concrete in place before setting up. Some forms remain in place permanently, but most forms are temporary and should be removed if they are no longer needed.
3. Many factors can affect the timing of concrete slab forms removal, those are Grade of Cement or Concrete Grade, higher grades can be cured quickly.
4. Different types of cement have different form removal time, like Rapid Hardening cement that will gain strength quickly so the forms can be removed early.
5. Temperature is also a factor for form removal time of concrete slabs. The concrete will quickly set in warm conditions and the forms can be removed early.
6. Size of Forms is also a factor for form removal time of concrete slabs. large concrete forms gain strength quickly and can be removed faster.

When Can I Remove Concrete Forms?

1. Forms should not be removed until the concrete is strong enough to safely carry any heavy loads.
2. The supporting time (the time between concrete installation and form removal) varies with the type of concrete used and the formwork. In standard building-carrying structures, side beams will not be removed within 7 days and supporting beams within 28 days of concrete installation.
3. No conditions can be sustained until the concrete reaches a force of at least twice the pressure at which the concrete can be placed during the strike.
4. The strength in question will be concrete using the same cement and composite, in equal proportions, cured under conditions of temperature and humidity similar to those available at work. Where possible, the forms should be left for a long time, as this will help in the treatment.

When To Strip Concrete Forms?

Forms can be stripped where the concrete is strong enough to support its weight and the weight of any loads to be carried. The required period will be determined by the specification of other functions. For activities where sector indicators have not yet been established for the removal of forms and ACI 347 Committee was proposed.

Their recommendations can be summarized as follows:

1. Pan joist Forms less than 30 inches wide, will take 3 days.
2. Pan joist Forms more than 30 inches wide, will take 4 days.
3. If the design load is greater than the dead load, it will take 14 days.
4. If the design load is less than the dead load, it will take 7 days.
5. For Soffits of joists, beams, and girders: If the clear span is under 10 feet, it will take 7 days to 4 days.
6. If the clear span is between 10 feet to 20 feet, it will take 14 days to 7 days.
7. If the clear span is greater than 20 feet, it will take 21 days to 14 days.
8. Permanent support intervals span is less than 10 meters it will take 4 days to 3 days.
9. Permanent support intervals span are between 10 to 20 meters, it will take 7 days to 4 days.
10. Permanent support intervals are greater than 20 feet, it will take 10 days to 7 days.

Formwork Removal Time Period | Deshuttering Time

Type of Formwork	Removal Time Period
Walls, columns, and vertical sides of beams	24 to 48 hours as may be decided by the engineer-in-charge.
Slabs (props left under)	3 days
Beam soffits (props left under)	7 days
Removal of props to slabs (Spanning upto 4.5 m)	7 days
Removal of props to slabs (Spanning over 4.5 m)	14 days
Removal of props to beams and arches (Spanning upto 6 m)	14 days
Removal of props to beams and arches (Spanning over 6 m)	21 days

FAQs – Concrete Formwork Removal Times

When should concrete forms be removed after pouring?

Concrete forms should generally be removed after the concrete has sufficiently hardened to support its weight and any imposed loads. Specific times vary depending on the type of concrete and the structure being formed.

What factors influence the time for formwork removal?

Factors such as the type of cement used (e.g., Ordinary Portland Cement, Rapid Hardening Cement), ambient temperature, size and complexity of the structure, and design loads all influence the formwork removal time.

How soon can forms be removed for walls and columns?

Forms for walls and columns can typically be removed within 24 to 48 hours, as determined by the engineer overseeing the project.

What is the recommended time to remove forms for slabs?

Slab forms, with props left underneath, are generally removed after 3 to 4 days to ensure the concrete has adequately cured and gained strength.

How long should soffit forms remain in place?

Soffit forms, supported by props, are usually removed after approximately 7 days to allow the concrete to achieve sufficient strength.

Are there different removal times based on the span of slabs and beams?

Yes, for slabs and beams, the removal time varies based on their span. Slabs spanning less than 4.5 meters can have their props removed after 7 days, whereas those spanning over 4.5 meters may require up to 14 days.

What about beams and arches?

Beams and arches, depending on their span, may require support for up to 21 days after pouring to ensure structural integrity.

Can forms be removed early to expedite construction?

Early removal of forms carries risks and should only be done when the concrete has reached sufficient strength to support its load and any imposed loads. Engineers and contractors must carefully assess these conditions before proceeding.

How does the type of cement affect formwork removal times?

Rapid Hardening Cement allows for quicker formwork removal compared to Ordinary Portland Cement, due to its accelerated strength gain properties.

What are the guidelines for removing formwork based on international standards?

International standards such as those outlined by ACI 347 provide specific recommendations for formwork removal times based on structural considerations and concrete strength requirements.