1. Sherwin-Williams Corothane (1 & 2)
Type: Single-component (Corothane 1) or two-component (Corothane 2) moisture-cured urethane
Best For: Industrial-grade metal surfaces exposed to extreme weather and heavy traffic
Durability: Very High – highly abrasion-resistant, chemical-resistant, and corrosion-proof
Weather Resistance: Excellent – moisture-proof, salt-resistant, and holds up against extreme Midwest temperatures
Slip Resistance: Needs an additive for walkable surfaces
Application: More difficult – high VOCs, requires PPE and good ventilation
Cure Time: Dries quickly but needs full curing time for chemical resistance
Pros:
✅ Industrial toughness – best for high-traffic metal surfaces
✅ Superior weather protection – great for extreme Midwest conditions
✅ Self-priming on some metals
Cons:
❌ Expensive – higher cost than standard urethane or acrylics
❌ Strong fumes – requires PPE and ventilation
❌ Not naturally slip-resistant – needs a non-slip additive
2. Sherwin-Williams Urethane Enamel (Industrial Urethane Alkyd)
Type: Single-component, urethane alkyd enamel
Best For: Moderate-duty metal surfaces that need a balance of durability and affordability
Durability: High – tougher than acrylic but not as extreme as Corothane
Weather Resistance: Good – resists moisture and rust but may require a primer
Slip Resistance: Needs an additive for foot traffic
Application: Moderate difficulty – solvent-based, but easier than Corothane
Cure Time: Dries in 4–8 hours, full cure in about 7 days
Pros:
✅ Durable and hard-wearing – ideal for moderate foot traffic
✅ Better adhesion than acrylics – sticks well to metal surfaces
✅ More affordable than Corothane
Cons:
❌ Requires more prep than DTM – primer recommended for best adhesion
❌ Not as tough as Corothane in extreme conditions
❌ Can yellow over time (common with alkyd-based coatings)
3. Benjamin Moore DTM (Direct-To-Metal) Acrylic
Type: Single-component, water-based acrylic
Best For: Light-duty residential metal surfaces
Durability: Moderate – fine for general use but not for heavy wear
Weather Resistance: Good, but less effective in harsh conditions
Slip Resistance: Can be improved with an additive
Application: Easiest – low VOCs, soap-and-water cleanup, DIY-friendly
Cure Time: Dries fast, full cure in 7 days
Pros:
✅ Low VOC & eco-friendly – no harsh fumes
✅ Easy to apply – DIY-friendly
✅ Decent adhesion to metal
Cons:
❌ Less durable than urethane and Corothane
❌ Not ideal for extreme Midwest weather without a topcoat
Comparison Table
| Feature | Sherwin-Williams Corothane | Sherwin-Williams Urethane Enamel | Benjamin Moore DTM Acrylic |
|---|---|---|---|
| Durability | Very High (industrial-grade) | High (moderate-duty) | Moderate (light-duty) |
| Best For | Extreme conditions, heavy traffic | Metal porches with moderate use | Light-duty residential metal |
| Weather Resistance | Excellent | Good | Good |
| Slip Resistance | Needs additive | Needs additive | Can be improved with additive |
| Ease of Application | Harder, needs PPE | Moderate | Easiest |
| Cure Time | Fast drying but longer for full cure | 4-8 hours touch dry, 7 days full cure | Fast drying |
| VOC Levels | High (solvent-based) | Medium (alkyd-based) | Low (water-based) |
| Cost | Most expensive | More affordable | Budget-friendly |
Which One Should You Choose for a Metal Porch in the Midwest?
- 🏆 Best for Extreme Durability & Harsh Weather:Sherwin-Williams Corothane
- If you need industrial toughness for high-traffic areas, this is the best option.
- Requires proper ventilation and PPE due to high VOCs.
- Needs a non-slip additive for safety.
- 🔧 Best for Moderate Foot Traffic & Budget-Friendly Durability:Sherwin-Williams Urethane Enamel
- Better than acrylics for wear resistance, but not as extreme as Corothane.
- More affordable than Corothane.
- May require a primer for best adhesion.
- 🏠 Best for DIY & Light Residential Use:Benjamin Moore DTM Acrylic
- Easiest to apply (water-based, low VOC).
- Best for general residential use but not for heavy traffic.
- Needs a topcoat or sealer for better longevity.
Final Recommendation for a Metal Porch in the Midwest:
- For the most durable & weather-resistant coating and metal refinishing: Sherwin-Williams Corothane (with a slip-resistant additive).
- For a good balance of durability, affordability, and ease of use: Sherwin-Williams Urethane Enamel.
- For an easy, budget-friendly option for light-duty residential use: Benjamin Moore DTM Acrylic.
