Metal roofing is a durable and attractive option for your home, but it requires proper installation and maintenance to ensure its performance and longevity. One of the most important aspects of metal roofing installation is how to screw down metal roofing correctly. Screwing down metal roofing is not as simple as it may seem, as there are many factors to consider, such as where to put the screws on a metal roof, how to screw down metal roof panels, how many inches do you overlap metal roofing, and where do you screw metal roofing. In this blog, we will explain how to screw down metal roofing in a step-by-step guide, and provide some tips and tricks to make the process easier and faster.
Step 1: Prepare the Roof Deck
Before you start screwing down metal roofing, you need to prepare the roof deck by making sure it is clean, dry, and level. You also need to install the underlayment, which is a layer of material that provides insulation, moisture protection, and soundproofing for your metal roof. The underlayment should be installed according to the manufacturer’s instructions, and should cover the entire roof deck, overlapping at least 6 inches at the edges and ends. You should also install the drip edge, which is a metal strip that prevents water from seeping under the metal roof, along the eaves and rakes of the roof.
Experts of a Spokane roofing company suggest that you should also check the roof deck for any damage, such as rot, holes, or cracks, and repair or replace it as needed before installing the metal roof panels. This will ensure that your metal roof has a solid and stable base to support it.
Step 2: Lay Out the Metal Roof Panels
The next step is to lay out the metal roof panels on the roof deck, starting from the bottom edge and working your way up. You should measure and mark the roof deck to ensure that the panels are aligned and spaced evenly. You should also cut the panels to fit the roof dimensions, using a circular saw with a metal-cutting blade or a pair of tin snips. You should leave a gap of about 1/4 inch between the panels and the drip edge, and a gap of about 2 inches between the panels and the ridge cap, to allow for expansion and contraction of the metal.
Step 3: Screw Down the Metal Roof Panels
The third step is to screw down the metal roof panels to the roof deck, using the appropriate screws and washers for your metal roofing type and thickness. You should use self-tapping screws with rubber washers that create a watertight seal around the screw head. You should also use a screw gun with an adjustable clutch that prevents overdriving or underdriving the screws. The screws should be driven perpendicular to the roof surface, and should penetrate at least 3/4 inch into the roof deck.
The most common question about how to screw down metal roofing is where to put the screws on a metal roof. The answer depends on the type and profile of your metal roof panels, but in general, there are two options: through the flat or the rib. Through the flat means that you screw the panels through the flat part of the panel, between the ribs. Through the rib means that you screw the panels through the raised part of the panel, along the ribs. Both methods have their pros and cons, but through the rib is usually preferred, as it provides more stability and strength, and reduces the risk of leaks and corrosion.
Another question about how to screw down metal roofing is how to screw down metal roof panels in terms of spacing and pattern. The spacing and pattern of the screws depend on the wind load and the roof pitch, but in general, you should follow these guidelines:
- For the eave and rake edges, you should place one screw every 12 inches, or every 6 inches in high-wind areas.
- For the field of the roof, you should place one screw every 24 inches, or every 12 inches in high-wind areas.
- For the ridge cap, you should place one screw every 12 inches, or every 6 inches in high-wind areas.
- For the valleys, hips, and flashings, you should place one screw every 9 inches, or every 6 inches in high-wind areas.
You should also use a staggered pattern for the screws, meaning that you alternate the position of the screws on each row of panels, to create a more secure and uniform attachment.
Step 4: Install the Ridge Cap and Other Accessories
The final step is to install the ridge cap and other accessories, such as vents, skylights, and chimneys, on your metal roof. The ridge cap is a metal piece that covers the ridge of the roof, where the two slopes meet. The ridge cap should be installed over the metal roof panels, overlapping them by at least 6 inches on each side. You should screw down the ridge cap using the same method and spacing as the metal roof panels, and seal the edges and joints with a high-quality metal roof sealant.
The other accessories, such as vents, skylights, and chimneys, should be installed according to the manufacturer’s instructions, and should be flashed and sealed properly to prevent leaks and damage. You should also use compatible materials and fasteners for the accessories, to avoid galvanic corrosion and other issues.
Conclusion
Screwing down metal roofing is a crucial part of metal roofing installation, as it affects the performance, durability, and appearance of your metal roof. By following the steps and tips we have provided, you can screw down metal roofing correctly and efficiently, and enjoy the benefits of metal roofing for years to come.
