Cold Weather Paving Resources for Asphalt Contractors

Asphalt paving in late fall or cold weather conditions presents unique challenges that can affect the quality and durability of the pavement. This page provides essential resources to help contractors navigate these challenges, offering guidance on best practices, MnDOT regulations, and important contractual documents to mitigate risks when paving in cold weather.

Key Documents and Resources:

1. Late Season Paving Advisory (2024)
   Summary: This advisory discusses the specific risks and limitations of paving in cold weather, emphasizing the importance of written approval for proceeding in prohibitive conditions and highlighting the use of warm mix asphalt technology.
   Why It Matters: This document provides contractors with strategic advice and tools, such as PaveCool, to manage cooling rates and achieve proper compaction, even in challenging weather conditions.
   Download the Late Season Paving Advisory
2. Late Season Paving Assumption of Risk Letter (2023)
   Summary: This letter serves as an acknowledgment that the owner or engineer accepts the risks of cold-weather paving, including voiding the warranty and waiving density requirements. It also outlines potential additional costs for the contractor.
   Why It Matters: This document protects contractors from penalties and liabilities by ensuring that the project owner is fully aware of and accepts the risks associated with paving under adverse conditions.
   Download the Late Season Paving Agreement
3. Contractual Notice Requirement for Late Season Paving
   Summary: This notice is sent when paving work is requested after November 1. It informs owners about the risks of cold-weather paving and holds them responsible for any consequences.
   Why It Matters: This document shifts the liability from the contractor to the project owner, ensuring that contractors are not held accountable for the inherent risks of late-season work.
   Download the Contractual Notice Requirement
4. MnDOT Cold Weather Bituminous Paving Guidance (2024)
   Summary: This document outlines critical steps and precautions for asphalt paving in cold weather to ensure quality and long-lasting performance. Topics include tarping loads, minimum temperature controls, compaction strategies, and use of PaveCool software to manage cooling rates.
   Why It Matters: Following this guidance can help ensure pavement integrity despite cold temperatures, avoiding common pitfalls like poor compaction and thermal segregation.
   Download the MnDOT Cold Weather Guidance

Best Practices for Cold Weather Paving

• Tarping Loads: Protect the asphalt mix from forming a “cold crust” by tarping loads during transport.
• Mixing Temperatures: Increase plant mixing temperatures as ambient temperatures drop, but avoid exceeding the specified maximum temperature.
• Paving in Thicker Lifts: Thicker lifts retain heat longer, improving compaction time.
• Use of Warm Mix Asphalt (WMA): WMA technologies allow for lower production temperatures while achieving the necessary compaction.

Tools to Assist with Cold Weather Paving

• PaveCool Software: This tool predicts asphalt cooling rates and helps contractors manage compaction timing.
  Download PaveCool for Windows and Mobile

For any questions or further assistance, please contact us at info@mnapa.org.