City of Dublin, Ohio
Building Standards
Policy Memorandum
POLICY#: CI02-01(07)SUBJECT: Cold Weather Concrete Policy
PURPOSE:
The purpose of this policy is to establish standards for placing concrete in cold weather conditions as defined by the American Concrete Institute Committee Report 306 (ACI 306). In accordance with ACI 306, concrete can be placed safely during the winter months if certain precautions are taken:
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The ground on which the concrete is to be placed shall not be frozen. The sub grade material should not only be firm and dry but it should be free of frost. Special precaution should be taken to insure that forms and reinforcing are also free of frost.
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The outside temperature shall be a minimum of 28° F and rising. If the temperature is below 28° F, then a written process by a registered design professional shall be submitted for review by the Building Official prior to the placement of concrete. At the time of inspection, all materials and methods shall be in place in accordance with the procedures outlined by the registered design professional for observance by the building inspector.
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After being placed, the concrete must be covered by the appropriate insulation to maintain a concrete temperature of 50° F for three (3) days. For a definition of cold weather and for the appropriate insulation values, see ACI 306 Chapter 1.1.
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The minimum concrete temperature as placed shall be 45-50° F.
It is the City of Dublin’s policy to discourage the use of admixtures such as calcium chloride. However, if admixtures are necessary, then ASTM C-494 “Standard Specifications for Chemical Admixtures for Concrete” shall be applied. In that event, the concrete contractor and the ready mix supplier shall work together to reach the desired results for the site conditions. A letter from the design engineer shall be sent to the building official describing the admixture(s) used to meet the conditions in the field. The use of air entrained concrete as a method of controlling the curing process is encouraged.
Concrete inspections are to be performed the day of the pour. Non-structural slabs may be inspected the day prior to the pour with permission from the building official.
This policy does not apply to concrete for pavement, base course, curb, curb and gutter, sidewalks, and driveways. For the policy and procedures for these items, see the Administrative Policy and Procedure from the City Engineer. Concrete work associated with the building construction, such as porches, exterior steps, garage floors, patios, etc. shall be constructed in accordance with ACI 306.
All design and construction shall be in compliance with the Ohio Building Code or the Residential Code of Ohio.
Effective Date: December 11, 2007
Jeffrey S. Tyler, AIA, CBO
Director