Planning an Indoor-Outdoor Remodel? Read This First.
A large Bi-Fold Door System can completely transform your home — opening up your living space, flooding interiors with natural light, and creating a seamless indoor-outdoor flow. But such a major investment deserves careful planning.
Before you order, take a few minutes to review these 9 common mistakes homeowners make when buying or installing a bi-fold door system — and how to avoid them.
1 | Confusing Door Configuration Options
When selecting your door’s configuration (how panels fold and stack), remember:
All configurations are viewed from the exterior looking in.
It’s easy to misread diagrams and end up with panels folding in the opposite direction from what you expected. A quick review with your dealer or installer can prevent this costly mix-up.
Pro Tip: Print your configuration drawing and stand outside your space to visualize how the doors will open.
2 | Forgetting the Daily Door
If you’ll use your bi-fold door daily, choose a configuration with a “daily door” — a single operable door that opens independently without unlatching the entire system.
Odd Configurations (like 3L, 5R, or 7L) include a daily door.
Even Configurations (like 4L or 2L2R) do not — meaning no exterior access if the system is closed.
Rule of thumb: Always include a daily door if the system will be your main entry to the backyard or patio.
3 | Measuring Incorrectly
Your door will only perform as well as it fits. Always hire a professional to measure your rough opening — twice.
AG Millworks custom builds every unit to your provided net frame dimensions, and even small measurement errors can cause delays or installation issues.
Tip: Ask your authorized AG Millworks dealer to recommend a certified installer to ensure precision and warranty compliance.
4 | Mismatched Transoms and Doors
Pairing a transom with your bi-fold system? Make sure they align perfectly.
Your transom design should match the panel width, stile size, and divided lite pattern of your bi-fold below. Mismatched proportions can disrupt sightlines and diminish the visual harmony of your design.
Pro Tip: Order your transom and bi-fold together from the same manufacturer to guarantee perfect alignment.
5 | Skipping the Overhang Check
If you’re installing a flush sill for smooth transitions, you need proper overhang coverage to protect against water intrusion. Without it, you risk leaks — and voided warranties.
Minimum Recommendation:
- 6' deep overhang for flush sills (varies by climate).
- Choose a raised sill or drainage track if adequate overhang isn’t possible.
Your AG Millworks dealer can help determine the best sill for your project conditions.
6 | Hiring an Inexperienced Installer
Bi-Fold systems are precision-engineered, top-hung doors that require expert handling. Poor installation can lead to misalignment, air or water leaks, and warranty loss.
Avoid this by:
- Asking your dealer for a certified installer experienced in large patio systems.
- Confirming that installers have handled AG Millworks or similar high-end systems before.
Remember, proper installation isn’t an upgrade — it’s a necessity.
7 | Choosing the Wrong Clad Color
Once your aluminum-clad color is chosen, it can’t be changed.
Before finalizing, confirm your color choice under natural light and ensure it complements existing windows or doors.
At AG Millworks, we offer custom color matching using high-performance 70% Kynar 500® paint finishes — ensuring long-lasting durability and a perfect aesthetic match across your home’s exterior.
8 | Forgetting the Retractable Screen
Don’t miss out on comfort. A retractable accordion screen lets you enjoy fresh air and open views — minus the insects.
These screens:
- Are built directly into the door jamb at the factory.
- Can be completely concealed when not in use.
- Are available with optional shades for added privacy.
- Are not sold separately.
Ask your dealer to include this feature in your quote — it’s much harder to add later.
9 | Overlooking Your Floor Plan
Large doors change how spaces function. Before finalizing your system, consider how furniture placement, pathways, and stacking direction will work together.
AG Millworks Bi-Folds can stack left, right, or both directions, giving you flexibility to maximize usable space inside and out.
Visualize: Mark where panels will fold before committing — especially if you have outdoor seating, lighting, or planters nearby.
Your Perfect Bi-Fold Door Starts with Expert Guidance
Avoiding these mistakes ensures your new bi-fold door system performs beautifully for years to come.
At AG Millworks, every large folding door is:
- Pre-hung and factory-tested for smooth operation.
- Custom-built to your exact specifications.
- Backed by our warranty for long-term peace of mind. Learn more about what our warranties cover.
Ready to Transform Your Home?
- Call 805-644-4494 to speak with our team of experts.
- Find your local dealer.
- Explore our Photo Gallery for design inspiration.
