HomeMy WebLinkAboutCold Weather Concrete Policy (EICCC)
Contact: Gary Hansen, EICCC President Phone: 319-743-6332 Email: ghansen@cityofmarion.org
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Cold Weather Requirements for Concrete Placement
1. Purpose
1.1 The purpose of this policy is to regulate the placement of concrete during cold weather by
application of currently accepted codes and standards. This policy is an interpretation of agreed
upon building codes and standards for adoption by member jurisdictions of the EICCC.
2. Scope
2.1 This policy shall apply to all new or replacement concrete that is placed during cold weather.
This shall include but is not limited to footings, walls, slabs, sidewalks, and drives.
3. Requirements
3.1 Cold weather practice is required when the National Weather Service forecasts an air
temperature below 40° F (4°C) at the time of concrete placement or during the required
protection period per Table 1 below.
Table 1 - Required Protection Period
Forecast Exposure Concrete Element
Required Protection Period
Normal
Concrete
Accelerated-Set
Concrete
> 32° F (0°C) < 40° F (4°C) Footings, Slabs on Grade, & Walls 2 Days 1 Day
> 10° F (-12°C) < 32° F (0°C) Footings & Slabs on Grade 3 Days 2 Days
> 10° F (-12°C) < 32° F (0°C) Walls 6 Days 4 Days
> 10° F (-12°C) < 32° F (0°C) Suspended Slabs & Beams Professional Design Required
< 10° F (-12°C) All Concrete Placement Professional Design Required
3.2 An approved method of weather protection must be on site for a passing inspection when
temperatures below 40° F (4°C) are expected within the first 24 hours after concrete placement.
3.3 Blankets, straw covered by secured tarp, or tented plastic with heat may be considered
adequate for cold weather protection and shall be kept in place for the duration of the required
protection period.
3.4 Concrete inspections will not be scheduled without approval of the building official when the
temperature is predicted to drop below 10° F (-12°C) during the required protection period.
3.5 Cold weather protection, procedures, and length of the protection period for elements that are
subject to full load when forms or shoring are removed (suspended slabs, cast-in-place concrete
beams, etc.) shall be as directed by a qualified design professional.
3.6 Forms, reinforcing bar, embedded plates, fillers, and the ground with which concrete is to
come in contact shall be free from ice and frost.
3.7 Dry calcium chloride shall not be field added to ready mix concrete. Calcium chloride and
any other admixture must be used according to the manufacturer’s specifications and guidelines.
3.8 Air entrained concrete shall be used when exposure to moisture and freezing and thawing
conditions are expected.
Contact: Gary Hansen, EICCC President Phone: 319-743-6332 Email: ghansen@cityofmarion.org
4. Recommended Best Practices per ACI
4.1 During cold weather, a high early strength concrete mix should be specified. Guidelines and
manufacturer’s recommendations for utilizing admixtures must be followed. Type III cement may be
substituted for Type I cement to accelerate the curing of cold-weather concrete.
4.2 Concrete materials and production methods should be selected so that the concrete temperature at
delivery is a minimum of the following specified temperature limits:
Outside/Ambient Air Temp: Concrete Temp:
Above 32° F (0°C) 60° F (16°C)
10° F (-12°C) to 32° F (0°C) 65° F (18°C)
4.3 An approved means to provide additional heat may be required to maintain the concrete temperature
at 55° F (13° C) for the duration of the required protection period as recommended by the ACI.
4.4 Cold weather protection should be kept in place in a manner that prevents excessive moisture loss.
4.5 Humidity is normally lowered when heating an enclosure. Membrane-forming curing compounds
should be used to ensure that the concrete surface does not dry out too soon and cause plastic shrinkage
cracks.
4.6 Fossil fuel burning heaters can cause carbonation of newly placed concrete surfaces. This may cause
unacceptable dusting. Therefore, combustion byproducts shall be vented from enclosures.
4.7 After the full duration of the protection period, concrete should be allowed to acclimatize to the
ambient temperature as gradually as practicable.
4.8 Specific design and procedure(s) by a qualified professional and professionally specified concrete
admixtures may be adequate, or allow less restrictive requirements, when approved by the qualified
design professional and the building official.