On-Site Solutions: A Troubleshooting Guide for Korniche Bifold Doors

Korniche bifold doors are a great choice, but even the best products can run into issues if they aren’t installed correctly. This comprehensive guide provides expert tips for troubleshooting Korniche bifold doors, based on the expertise of our on-site support team.

Flush Seals

A quick visual inspection of the flush seals can tell you a lot about the quality of the installation. A good installation will have no gaps or overhangs in the seals.

Overhang of seals against the sill: If you see an overhang below the rollers, it means the bottom roller is positioned too high and the sashes are sitting too low.
Overhang of seals against the head of the frame: This indicates that the head of the frame has been packed down, “sandwiching” the sashes and causing the rollers to scrape along the track.
Gap in seals above the sashes and frame: If you notice a gap here, check to see if the head has been pulled up too high with the fixings. This could also be a sign of incorrect toe and heel or an incorrect roller position.

Compression on Shootbolt Rods

If your door handles are difficult to operate or your key won’t turn, it could be due to pressure on the shootbolt rods. This is often caused by the door’s frame being “sandwiched” due to incorrect toe and heel.

How to Identify the Problem:

Look for an overhang on the gaskets on the shootbolt section of the door.
Check for a gap at the top of the seals above the shootbolt.
The shootbolt handle may not sit flush and could be pointing slightly diagonally.
The handle will feel tight, and the key won’t turn.

How to Fix It:

You will need to correct the toe and heel of the door to relieve the pressure on the rods. This will bring the door up to the correct height, taking the tension off the shootbolt mechanism and allowing it to lock properly. For a full guide on this process, please see the Toe & Heel section.

Gap Measuring and Checking Alignment

If you feel compression on the shootbolt, or if the doors are catching, measuring the gaps is the first step to figuring out the problem. A tell-tale sign of pressure on the shootbolt is if the handle is not sitting straight down but is pointing diagonally.

Remove the closer, which is the profile that covers the gap between the traffic door and the next frame.
Measure the width and height of all the sashes from aluminium to aluminium, do not include the seals.
Measure the gap between the frames. The ideal measurements are:
- Closer Gap: 17mm
- Shootbolt Keep: 16mm
- Jamb (against the frame): 15-16mm

If your measurements are below or above these guidelines, the cams may be catching on the profile. If they are above, you will likely have drafts.

Adjusting Door Compression and Cams

If your traffic door feels loose or too tight when using the handle, you may need to adjust the cams.

You will need a 4mm Allen key.

To loosen the seal, turn the cam 90 degrees clockwise.
To tighten the seal, turn the cam 90 degrees counter-clockwise.

Pro-Tip: Adjusting cams can help with seasonal changes. We recommend loosening the cams in the summer when materials expand and tightening them in the winter to prevent drafts. If a client struggles with a tight handle, you can loosen the two cams in the middle of the frame around the handle and tighten the cams at the top and bottom for a better balance.

Hinge Replacement

Incorrect toe and heel can put extra stress on the hinges, causing them to fail. Here’s how to replace a faulty hinge:

Use a PZ2 screwdriver bit to remove the two middle screws first, then the four outer screws.
Replace the hinge and secure it with the screws. Make sure they are tight.
Important: Only replace one hinge at a time. Never release more than two hinges at once, or the door could drop and cause damage.

Handle and Shootbolt Replacement

If a handle or shootbolt is damaged, faulty, or you just want a new colour, you can change them.

Handle Replacement

First, loosen the barrel screw to free the locking barrel.
From the inside of the door, unscrew the screws holding the handle in place.
Have someone hold the handle on the outside of the door to prevent it from dropping. Gently pull both sides to remove the handles.
To replace, reverse the process. Have someone hold the new handle in place on the outside while you tighten the screws from the inside. Make sure all screws are tight.

Shootbolt Replacement

Turn the shootbolt handle to the open position.
Unscrew both the top and bottom screws.
Pull to remove the handle section.
Place the new handle in position and tighten the screws.
Finally, check that the new shootbolt twists and the system locks correctly.

The Toe and Heel Process

If your measurements are off, or the doors are catching on the outer frame, you’ll need to re-toe and heel the glazing to fix the alignment.

Assess the Door: First, check the door’s alignment. Look for rubbing, sticking, or gaps. Use a spirit level to see if it’s hanging evenly. This helps you figure out where the adjustment is needed.
Remove the Speed Bead: Use a speed bead removal tool to remove one sash at a time. Work your way along, being careful not to damage the beads or the frame. Keep the beads organised so you know where they go. Never remove all the beads and leave the glass in the frame, as it could fall out. Have someone hold the glass while you remove the glazing beads.
Remove the Glazing: Carefully remove the glass panel.
Identify Packer Points: The toe is the packers placed at the bottom corner on the roller side of the door. This packer supports the weight and keeps the door from dropping. The heel is the packer placed at the top corner on the opposite side (the handle side). This acts as a counterbalance and helps keep the frame square.
Insert the Toe Packer: Place a packer (approximately 5mm) at the toe position next to the roller.
Insert the Glazing and Heel Packer: Place packers at the top, handle-side corner. Use a glazing shovel to gently lever the door frame up at the bottom corner (the toe) to create a gap at the top (the heel). While the frame is lifted, insert packers into the top corner until the glass is snug and the door is level. You might need to adjust the number of packers to get the correct alignment.
Check the Alignment: Once the packers are in place, check the door’s alignment again. Open and close it to ensure smooth operation. If it’s still misaligned, adjust the packers as needed.
Replace the Bead: When you’re happy with the alignment, re-install the beading. Start with the top and bottom beads to secure the glass, then fit the side beads.

For a bifold door system with multiple panels, you work in a zigzag pattern, starting with the panel that is fixed to the wall and working your way toward the traffic door. Proper toeing and heeling is key to ensuring the longevity and smooth operation of your bifold doors.

Kit Form: Assembly Advice

Korniche bifold doors come in a kit form, but we’ve noticed a few common issues that can lead to problems later on. Here’s a checklist to make sure your assembly goes smoothly and you don’t need a call-out.

Seal Joins: Make sure the C corners are sitting snug in the corners of the frame. If the first sash is positioned too low, it can lead to every subsequent sash being low and dragging along the bottom.
Don’t Trap Qlon Seals: When putting the frame together, be careful not to trap the Qlon seal. We often see seals that are too short on kit form doors, which is a clear sign they were trapped during assembly.
Check Sash Levels: Ensure that all sashes are level when you join them together. If they’re not, you could end up with a stepped effect, leading to a gap at the top or an overhang at the bottom, which can cause drafts.
Use the Right Tools: Use a PZ2 screwdriver bit for the screws. It’s important to use the correct bit to avoid stripping the screw heads.
Tighten All Screws: This might seem obvious, but it’s crucial. Make sure all screws are tight to prevent a sash from coming loose or falling off.
Roller Positions: Ensure your roller positions are correct before you start glazing. Incorrect placement can cause the bottom roller to sit too high, meaning the sashes sit too low and drag.

By paying close attention to these details, you can ensure a professional result and a perfectly functioning bifold door system.