Large Automatic Chicken Coop Door Sizing Guide
Why Coop Tender's "large" openings (10" to 21") outperform standard 8"×8" competitor doors—and how to choose the right size for your flock.
Why Size Matters: Industry Comparison
Industry Standard: 8"×8" = 64 square inches
Most commercial automatic chicken doors feature 8"×8" openings. While adequate for bantams, this creates bottlenecks and stress for standard and large flocks.
Coop Tender Large Doors: 10" to 21" openings
Our "large" door range provides 56% to 456% more opening area than competitor "standard" doors—dramatically better traffic flow for any flock size.
10"×10": +56% larger
12"×12": +125% larger ⭐
15"×15": +252% larger
21"×18": +456% larger
Quick Answer: Which Large Door Size?
10"×10" Standard: 1-12 chickens (Rhode Island Red, Leghorn, Plymouth Rock) under 7 lbs
12"×12" Large ⭐: 8-20 chickens, large breeds (Orpingtons, Wyandottes) — Most Popular
15"×15" Extra Large: 15-49 chickens, giant breeds (Jersey Giant, Brahma), ducks
21"×18" Certified Humane: 50+ chickens, turkeys, geese, commercial operations
Large Door Size Comparison
| Specification | 10"×10" | 12"×12" ⭐ | 15"×15" | 21"×18" |
|---|---|---|---|---|
| Opening Area | 100 sq. in. | 144 sq. in. | 225 sq. in. | 378 sq. in. |
| vs. 8"×8" Standard | +56% larger | +125% larger | +252% larger | +456% larger |
| Flock Size | 1-12 chickens | 8-20 chickens | 15-49 chickens | 50+ chickens |
| Max Bird Weight | 6-7 lbs | 8-9 lbs | 10-12 lbs | Unlimited |
| Best For | Standard layers | Large breeds | Giants, ducks | Turkeys, geese |
| Starting Price | $329 | $349 | $369 | $449 |
⭐ 12"×12" Large Door is our most popular size across all categories
10"×10" Standard Door (Large vs. Competitors)
Why we call 10"×10" "standard": While most competitors offer 8"×8" doors, Coop Tender's baseline 10"×10" provides 56% more opening area—better accommodating standard backyard chickens and reducing stress during flock movement.
👥 Flock Size
1-8 chickens
📏 Max Weight
6-7 lbs per bird
📐 Cutout Size
13½" × 26½"
🐔 Perfect Breeds for 10"×10":
- Rhode Island Red
- Leghorn
- Plymouth Rock
- Australorp (standard)
- Sussex (light)
- New Hampshire Red
- Dominique
- Welsummer
- Barnevelder
- Maran (standard)
✅ Choose 10"×10" When:
- You have 4-8 chickens of standard egg-laying breeds
- Your largest bird is under 7 lbs fully grown
- You're upgrading from an 8"×8" competitor door
- Installation space is somewhat limited
12"×12" Large Door
🌟 Why 12"×12" is our most popular size: Handles 90% of backyard scenarios. Only $20 more than 10"×10", but accommodates larger breeds, bigger flocks, and future expansion. Perfect balance of capacity and value.
👥 Flock Size
8-20 chickens
📏 Max Weight
8-9 lbs per bird
📐 Cutout Size
15" × 28¼"
🐔 Perfect Breeds for 12"×12":
- Buff Orpington
- Wyandotte
- Barred Rock
- Sussex (standard)
- Australorp (large)
- Rhode Island Red (large)
- Plymouth Rock (large)
- Brahma (light)
- Cochin (standard)
- Delaware
- New Hampshire
- Langshan
✅ Choose 12"×12" When:
- You have 8-20 chickens of any standard or large breed
- Any birds are 7+ lbs (Orpingtons, Wyandottes, large Rocks)
- You want room for growth - planning to expand flock
- You're unsure between 10"×10" and 12"×12" - only $20 difference
15"×15" Extra Large Door
Giant breeds and high-traffic flocks: The 15"×15" opening provides 252% more area than standard 8"×8" doors. Essential for Jersey Giants, large Brahmas, ducks, and flocks exceeding 15 birds.
👥 Flock Size
15-49 chickens
📏 Max Weight
10-12 lbs per bird
📐 Cutout Size
17½" × 34¼"
🐔🦆 Perfect Birds for 15"×15":
- Jersey Giant
- Brahma (standard/exhibition)
- Cochin (large specimens)
- Orpington (exhibition size)
- Marans (large strain)
- Pekin Duck
- Rouen Duck
- Muscovy Duck
- Cayuga Duck
- Swedish Duck
✅ Choose 15"×15" When:
- Giant breed enthusiasts: Jersey Giants, large Brahmas, exhibition Cochins
- Larger flocks: 15-49 birds requiring high-traffic capacity
- Duck coops: Most duck breeds need 15"×15" minimum
- Mixed poultry: Chickens + ducks together
- Commercial breeding: Heavy breed operations
📐 Installation Consideration:
Requires 17½" wide × 34¼" high cutout. Ensure adequate wall space and structural support. Not recommended for thin-walled coops without reinforcement.
21"×18" Certified Humane Door
🏆 Commercial-grade capacity: With 378 square inches (456% larger than 8"×8"), this door handles turkeys, geese, and high-volume commercial operations. Meets Certified Humane® standards for professional poultry facilities.
👥 Flock Size
50+ chickens
📏 Max Weight
Unlimited
📐 Cutout Size
24" × 41½"
🦃🦢 Perfect Birds for 21"×18":
- All Turkey Breeds
- Broad Breasted Bronze
- Bourbon Red
- Narragansett
- Royal Palm
- All Goose Breeds
- Toulouse
- Embden
- African
- Chinese
✅ Choose 21"×18" When:
- Turkey operations: All turkey breeds require this size minimum
- Goose housing: Full-size geese need adequate clearance
- Commercial egg production: High-volume facilities (50-200+ birds)
- Certified operations: Meets Certified Humane® standards
- Multi-species farms: Mixed large bird operations
🏆 Certified Humane® Compliant:
Meets Certified Humane® standards for commercial poultry operations, ensuring adequate access for high-density flocks while maintaining animal welfare requirements. Essential for certified organic or humane label operations.
📐 Installation Consideration:
Requires 24" wide × 41½" high cutout—essentially a small doorway. Structural support recommended and is typically installed in barn-style or commercial construction. Professional installation recommended for proper structural support.
Why Coop Tender's Large Doors Outperform Competitors
📏 Larger Openings
Our 10"×10" "standard" is 56% larger than competitor 8"×8" doors. Our largest provides 456% more opening area—dramatically better traffic flow.
🔒 Steel Worm Drive
Solid 5/8" steel Acme threaded drive—not cables that predators can defeat. Mechanical lock security on all door sizes.
⏱️ 10-15 Year Lifespan
Proven durability with solid wood and steel construction. Competitor plastic and cable systems fail in 2-5 years.
🌐 Global WiFi Control
Universal Web App™ works on any device, anywhere. No proprietary apps or local network limitations.
☀️ True Solar Capability
15-watt panels with 5+ day battery backup. Competitors' smaller panels fail during cloudy weather.
Made in USA
Pennsylvania manufacturing with made-to-order quality. Latest improvements in every door vs. warehouse inventory.
Popular Breed Size Guide
| Breed/Bird Type | Adult Weight | Recommended Door | Notes |
|---|---|---|---|
| STANDARD EGG LAYERS (10"×10") | |||
| Leghorn | 4-5 lbs | 10"×10" | Lightweight layers |
| Rhode Island Red | 6-7 lbs | 10"×10" or 12"×12" | 12"×12" if flock > 8 |
| Plymouth Rock | 6-7 lbs | 10"×10" or 12"×12" | 12"×12" for large specimens |
| LARGE DUAL-PURPOSE (12"×12") ⭐ | |||
| Buff Orpington | 7-8 lbs | 12"×12" | Popular, needs space |
| Wyandotte | 6-8 lbs | 12"×12" | Fluffy, larger opening |
| Barred Rock | 6-8 lbs | 12"×12" | Substantial birds |
| Sussex | 6-9 lbs | 12"×12" | Heavy breed |
| Australorp | 6-8 lbs | 12"×12" | Can get large |
| GIANT BREEDS & DUCKS (15"×15") | |||
| Jersey Giant | 10-13 lbs | 15"×15" | Largest chicken breed |
| Brahma (Standard) | 9-12 lbs | 12"×12" or 15"×15" | 15"×15" for large specimens |
| Cochin (Large) | 8-11 lbs | 12"×12" or 15"×15" | Very fluffy, needs space |
| Pekin Duck | 8-11 lbs | 15"×15" | Most common duck breed |
| Muscovy Duck | 10-15 lbs | 15"×15" | Large domestic duck |
| TURKEYS & GEESE (21"×18") | |||
| All Turkey Breeds | 15-40 lbs | 21"×18" | Minimum size required |
| Toulouse Goose | 15-25 lbs | 21"×18" | Large domestic goose |
| Embden Goose | 20-30 lbs | 21"×18" | Largest domestic goose |
Traffic Flow Comparison
8"×8" Competitor
⚠️
BOTTLENECK
2-3 birds simultaneously
Fighting common
10"×10" Standard
✓
GOOD FLOW
3-4 birds simultaneously
Reduced stress
12"×12" Large ⭐
✓✓
EXCELLENT
4-5 birds simultaneously
Zero bottlenecks
15"×15" X-Large
✓✓✓
HIGH CAPACITY
5-7 birds simultaneously
Commercial grade
21"×18" Certified
✓✓✓✓
MAXIMUM
8-12 birds simultaneously
Industrial capacity
Frequently Asked Questions
How do I choose between 10"×10", 12"×12", and 15"×15"?
10"×10": 1-12 standard chickens under 7 lbs. 12"×12": 8-20 chickens or any large breeds (Orpingtons, Wyandottes) - most popular. 15"×15": Giant breeds (Jersey Giant, Brahma), ducks, or flocks over 15 birds. When in doubt, size up—only $20-40 difference between sizes.
Why is Coop Tender's 10"×10" called "standard" when it's so much larger than competitors?
Industry standard has been 8"×8" for years, but that size creates bottlenecks for modern backyard flocks. Our 10"×10" baseline provides 56% more area than competitor "standard" doors, making it truly appropriate for standard-sized chickens. We're setting a new, better standard.
I have Buff Orpingtons. Which size should I choose?
Definitely choose the 12"×12" large door. Buff Orpingtons are hefty birds (7-8 lbs) with fluffy plumage requiring extra clearance. If you have more than 10 Orpingtons or plan to expand, consider the 15"×15" for even better traffic flow.
Do I need the 21"×18" door for regular chickens if I have a large flock?
Not for chickens—the 15"×15" handles flocks up to 49 chickens comfortably. The 21"×18" Certified Humane door is specifically for turkeys, geese, or commercial operations with 50+ birds. For chicken-only operations under 50 birds, the 15"×15" provides excellent capacity at lower cost.
Can ducks use the same door as chickens?
Most duck breeds need the 15"×15" opening minimum due to their wider body shape and waddling gait. Pekin, Rouen, and Muscovy ducks are 8-15 lbs and require more horizontal clearance than chickens of similar weight. Don't try to fit ducks through 10"×10" or 12"×12" doors.
What's the installation difficulty difference between sizes?
10"×10", 12"×12", and 15"×15" all use similar installation processes—mainly cutting the opening and securing the unit. The 21"×18" requires more substantial structural support due to its size and weight. If you can install one size, you can install any of the first three with minimal difficulty increase.
Is a larger door less secure against predators?
No—all Coop Tender doors use the same solid steel worm drive mechanism regardless of size. When closed, a 21"×18" door provides identical security to a 10"×10" door. The steel worm drive creates a mechanical lock that predators cannot defeat, regardless of door opening dimensions.
Can I upgrade to a larger door later?
You'd need to purchase a new door and enlarge your cutout opening, which costs more than choosing the right size initially. The price difference between sizes is minimal ($20-40) compared to the cost and hassle of upgrading later. If you're considering expansion, choose the larger size now.
Quick Decision Guide
Do you have turkeys or geese?
→ Choose 21"×18" Certified Humane Door
Do you have ducks or giant chicken breeds?
→ Choose 15"×15" Extra Large Door
Do you have 8-15 chickens or large breeds?
→ Choose 12"×12" Large Door ⭐ Most Popular
Do you have 4-8 standard chickens under 7 lbs?
→ Choose 10"×10" Standard Door
💡 Pro Tip: When uncertain between two sizes, choose the larger option. The minimal cost difference prevents future regrets.
Installation Cutout Requirements
| Door Size | Opening | Required Cutout | Unit Weight |
|---|---|---|---|
| 10"×10" Standard | 10" × 10" | 13½" × 26½" | ~15 lbs |
| 12"×12" Large ⭐ | 12" × 12" | 15" × 28¼" | ~17 lbs |
| 15"×15" Extra Large | 15" × 15" | 17½" × 34¼" | ~22 lbs |
| 21"×18" Certified Humane | 21" × 18" | 24" × 41½" | ~35 lbs |
Note: Cutout dimensions include space for integrated controller. Verify wall space before ordering.
Need Help Choosing Your Large Door Size?
Get personalized sizing recommendations from our expert team based on your breeds, flock size, and setup.
📧 Email: support@cooptender.com
Include your chicken breeds and flock size
Response within 1 business day
Or view our Complete Sizing Guide covering all door sizes (8" to 21")
Ready to Order Your Large Door?
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