FAQ About Polycarbonate Installation: Expert Views on Slope and Waterproofing
Below is a list of FAQs that may help you:
1. How to Create a Slope?
Experts recommend creating at least a 5-degree slope. Here’s an easy calculation to achieve the required 5-degree slope: If you have a roof length of 12 feet, the upper roof end should be 1 foot taller than the lower end.
Option 1: You can cut the whole beam diagonally to create two shims for the slope.
Option 2: Install or reinstall the ledger board and attach it to the roof or the wall.
2. Is Flashing Necessary at the Edges of the Polycarbonate Roof?
You can use aluminum or galvanized metal flashings at the edges to ensure that rainwater doesn’t seep into the gaps between the polycarbonate panels and the beams.
Alternatively, you can use an overhang instead of flashing.
3. Overhang.
An overhang extends the polycarbonate panels beyond the edge of the beam.
Recommend overhang is 6 inches. The maximum overhang is 12 inches.
4. Gutters
Installing gutters along the edge of your polycarbonate sheets is a great way to manage water runoff. Gutters collect rainwater from the roof, directing it away from your patio or structure to prevent leaks and damage.
To install gutters:
Attach the gutter securely along the bottom edge of the polycarbonate sheets.
Ensure proper alignment so that the water flows seamlessly into the gutter system.
5. How to Extend the Length of Polycarbonate Sheets: Overlapping or H Profiles
When the length of your polycarbonate sheets isn’t sufficient to cover the entire area, there are two primary methods to achieve the desired length: overlapping the sheets or using an H profile to connect two panels. However, neither method is ideal, so it’s always better to use a single, continuous panel whenever possible.
Overlapping Polycarbonate Sheets
One way to extend the length of your installation is by overlapping the sheets. This method creates a seamless joint where one sheet overlaps the next, ensuring water flows off the roof without seeping between the sheets.
How to Overlap Sheets Properly:
• Overlap the polycarbonate sheets by at least 12 inches to prevent water penetration at the joint.
• Ensure the overlap is aligned with the slope of the roof so water runs down and off instead of getting trapped.
• Maintain a minimum roof slope of 5 degrees when using this method to ensure effective water drainage.
• Adjust the height of the rafters. For example if you use 14 mm panels the height of 1 rafters should be 14 mm higher than another.
Using an H Profile to Connect Panels:
Align the Sheets: Position the edges of the two polycarbonate sheets you want to join, ensuring they are straight and properly aligned.
Insert the H Profile: Slide the H profile into place between the sheets, ensuring a snug and tight fit along the joint.
Secure the Panels: Use screws with rubber washers to fix the panels and the H profile to the supporting structure. This prevents leaks and ensures stability.
Seal with Silicone: Apply a bead of silicone along both sides of the H profile where it meets the sheets. This provides an additional layer of waterproofing and helps prevent dust or debris from entering the joint.
6. How Do I Connect the Polycarbonate Roof to My House Wall?
When attaching a polycarbonate roof to the wall of a house or building, you should use L flashing to create a waterproof seal between the roof and the wall. This prevents water from getting behind the sheets and into the house.
To connect to a house wall:
Place the L flashing between the top edge of the polycarbonate sheets and the wall.
Secure the L flashing tightly to both the wall and the sheets, ensuring there are no gaps.
7. List of Materials for Twin-Wall Polycarbonate Panel Installation:
- Polycarbonate Sheets: The main and key component.
- Connectors (H or Snap Profiles): Used to connect two sheets together.
- U Caps: Used to cover the ends of the sheets.
- Vented Tape: Protects against moisture and dust particles.
- Screws with Plastic Washers or Screws with Neoprene Washers: Ideal for preventing rainwater leaks.
Tools:
- Measuring Tape: Essential for adjusting the polycarbonate sheets.
- Drill: Useful for creating precise screw holes.
- Circular Saw or Jigsaw: Used to cut and adjust panels.
- Safety Glasses: Protect against potential eye damage during installation.
8. How to Calculate the Number of Screws
For proper installation, it’s recommended to place screws every 2 feet in each direction. At the same time, you should place screws where you have an H or snap connector.
Here’s a reference for a standard 4 ft x 8 ft sheet size:
- For one sheet (4 ft x 8 ft), you will need approximately 15 screws.
- For two sheets connected with an H or snap profile (4 ft x 8 ft), you will need around 25 screws.
- For three sheets connected with an H or snap profile (4 ft x 8 ft), you will need about 45 screws.
