Formwork Removal Time for Concrete Members in Different Seasons According to Standards
The timing for removing formwork from concrete structures is critical and depends on several factors, including the type of structural member, curing temperature, cement type, and environmental conditions. The goal is to ensure that the concrete has developed sufficient strength to support itself and any imposed loads.
General Guidelines (Based on ACI, BS, and IS Standard Codes):
Types of Concrete Members:
Vertical elements (columns, walls)
Slabs (soffit removal)
Beams and girders (soffit and sides)
Cantilever structures
Recommended Minimum Stripping Times
| Type of Member | Temperature Conditions | Minimum Stripping Time |
|--------------------------|-----------------------|------------------------------|
| Vertical forms (columns, walls) | Normal (≥15°C) | 24-48 hours |
| | Cold (<10°C) | 3-5 days |
| | Hot (>30°C) | 18-24 hours |
| Slabs (props left under) | Normal (≥15°C) | 2-3 days |
| | Cold (<10°C) | 5-7 days |
| | Hot (>30°C) | 2 days |
| Slabs (props removed) | Normal (≥15°C) | 7 days |
| | Cold (<10°C) | 10-14 days |
| | Hot (>30°C) | 5 days |
| Beam sides | Normal (≥15°C) | 2-3 days |
| | Cold (<10°C) | 5-7 days |
| | Hot (>30°C) | 2 days |
| Beam soffit (props left) | Normal (≥15°C) | 7 days |
| | Cold (<10°C) | 10-14 days |
| | Hot (>30°C) | 5 days |
| Beam soffit (props removed) | Normal (≥15°C) | 14 days |
| | Cold (<10°C) | 21 days |
| | Hot (>30°C) | 10 days |
| Cantilever members | Normal (≥15°C) | 14 days |
| | Cold (<10°C) | 21 days |
| | Hot (>30°C) | 10 days |
Notes:
Above times are typical for concrete using ordinary Portland cement.
In cold weather, setting and strength gain slow down, requiring longer formwork retention.
In hot weather, concrete sets faster, and forms may be removed sooner, but ensure adequate strength gain.
Stripping times can be reduced if rapid hardening cement or admixtures are used, but field strength tests (such as making and testing cubes or cylinders) should always guide early stripping.
Where possible, props should be left in place under slabs/beams after initial formwork removal until full strength is achieved.
Standard References
ACI 347R "Guide to Formwork for Concrete"
BS 8110 "Structural Use of Concrete"
IS 456:2000 "Code of Practice for Plain and Reinforced Concrete"
About Clinic Beton Iran Group
Clinic Beton Iran Group (with Rayeh Sabz Beton and Zharf Taban Mehr), operating under the international brand RBS-CONTECH, provides technical consultation, quality products, and equipment for concrete formwork, curing, and professional construction solutions.
Contact Information:
Website: clinicbeton.com
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Email: clinicbeton.com(AT)gmail.com
Phone: +98 21 88070173 / +98 21 88584906
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