Staples vs. Cap Nails in Roofing: What You Need to Know
When it comes to roofing, even the smallest decisions can make a big impact—especially the type of fastener you use. The choice between staples and cap nails may seem small, but it impacts the strength, safety, and code rules of your roof installation.
This article explains the main differences, advantages, and disadvantages of each fastener. It also gives helpful tips to help you choose the best one for your next roofing project.
Roofing Staples: Fast and Affordable
What Are Roofing Staples?
Roofing staples are U-shaped metal fasteners, typically made from galvanized steel. They’re used to secure materials like synthetic underlayment or felt paper to the roof deck. Staples are applied using a staple gun, making them a common choice for speed-focused installations.
✅ Pros of Roofing Staples:
Fast Application: Staple guns make the process quick, ideal for large-scale jobs with tight timelines.
Lower Cost: Staples are generally cheaper than cap nails, helping reduce upfront material expenses.
Lightweight Tools: Staple guns are easy to handle, which reduces fatigue for installers covering large surfaces.
❌ Cons of Roofing Staples:
Weaker Holding Strength: Staples don’t grip roofing materials as securely, especially under high wind loads.
Code Limitations: Many municipalities prohibit or discourage staples for roof underlayment due to reliability concerns.
Risk of Damage: Staples can tear underlayment if overdriven or misaligned, reducing waterproofing effectiveness.
Cap Nails: Stronger, Safer, and Code-Compliant
What Are Cap Nails?
Cap nails feature a large plastic or metal head that helps secure roofing underlayment more effectively. They are often used in synthetic underlayment systems. These fasteners are installed with special pneumatic nail guns.
✅ Pros of Cap Nails:
Superior Holding Power: The wide cap helps prevent tearing and keeps the underlayment firmly attached, even in windy conditions.
Building Code Friendly: Many roofing codes mandate or recommend cap nails for underlayment attachment.
Enhanced Durability: Less risk of material uplift, puncture, or premature wear due to cap head pressure distribution.
❌ Cons of Cap Nails:
Higher Cost: Cap nails are more expensive than staples, both in material cost and required equipment.
Slower Installation: Driving cap nails takes longer, particularly on steep or complex roofs.
Tool Requirements: Pneumatic cap nailers are heavier and more expensive than staple guns, potentially increasing labor fatigue and overhead.
Side-by-Side Comparison
| Feature | Roofing Staples | Cap Nails |
|---|---|---|
| Installation Speed | Fast | Slower |
| Cost | Lower upfront cost | Higher material and tool cost |
| Holding Strength | Moderate | Strong |
| Durability | Lower | Higher |
| Tool Weight | Lightweight staple gun | Heavier cap nailer |
| Code Compliance | Limited in many areas | Widely accepted/required |
| Best Use | Budget-friendly installs | Long-term, high-performance roofs |
Which Fastener Is Right for Your Roof?
Your decision between cap nails and staples should be based on a few key factors:
Local Building Codes: Many regions—especially those with strict wind-resistance standards—require cap nails. Always check your local code before proceeding.
Weather Exposure: If your area has strong winds, heavy rain, or storms, cap nails are a safer choice.
Project Budget: Staples may save money upfront, but they could cost more in repairs or code violations down the road.
Installer Experience: Proper installation is essential. Even cap nails won’t perform well if driven incorrectly or with the wrong tools.
Final Thoughts
When it comes to roofing fasteners, cap nails offer greater durability, better weather resistance, and meet more building codes. Roofing staples can make the job faster and cheaper at first. However, they may not be the best choice for the long run, especially if local codes do not allow them.
For most home roofing projects, cap nails are the best choice. This is especially true for projects with synthetic underlayment or in tough weather conditions. Cap nails are reliable and effective.