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Deck Preparation

Understanding the Foundation of Your Roof

What is a Roof Deck and
Why Does It Matter?

The roof deck is the critical layer between your roof’s structural components and insulation. Located directly over roof trusses, it creates a smooth surface to support roof felt, shingles, and other roofing materials. While often overlooked, the roof deck is as important to your roof as a foundation is to your home.

Windsor-Essex's Guide to Essential Roofing Infrastructure

Common Roof Deck Materials

Plywood

More durable than many realize, plywood is constructed from multiple layers of wood veneer. Its unique composition allows it to:

- Resist moisture effectively
- Dry out quickly when wet
- Provide long-lasting structural support

Oriented Strand Board (OSB)

Manufactured from wood strands and waterproof resin, OSB offers:

- Rigid structural support
- Moisture resistance
- A more cost-effective decking option
- Ability to endure years with minimal damage

Traditional 1X Board Decking

Prevalent in homes built before the 1990s, this decking typically uses:

- 1X6 or 1X8 boards
- Horizontal installation across roof trusses
- Slight gaps between boards
- Tongue-and-groove joints in older residential roofs

When Layering Might Be an Option

Building Over-the-Top

  • Price is the primary attraction for building over an existing roof. Adding a layer to existing asphalt shingles saves removal costs.

  • This is not realistic for most roofing renovations, but roofs in relatively good condition may be candidates.

  • Your existing roof must be in above-average condition to support an additional layer.

  • Avoid adding layers if shingles are:
    • Bent
    • Cupped
    • Warped
    • Currently leaking

Critical Knowledge for Homeowners

Removal and New Roof Installation

Understanding the Risks of Multiple Layers

  • A single layer of asphalt shingles can be roofed over once, but multiple layers involve significant risks.
  • Keeping the existing roof means retaining old flashings and vent boots.
  • Layered roofing is often a temporary fix that can become a more expensive problem later.


Disadvantages include:

  • Added weight that could compromise roof structural integrity
  • Increased removal costs for future roof replacements
  • Potential warranty invalidation by manufacturers

Delivering expert roofing solutions and reliability to Windsor-Essex homes and businesses since 1920.

Quick Links

Roofing Services

Contact Information

Phone Number

(519) 737-1920

Email Address

info@dayusroofing.com

Our Location

5120 Halford Drive Oldcaste, Ontario N9G 0B8

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