Metal Shed Roofing 101: A Complete Overview

Metal shed roofing is a popular choice for homeowners due to its durability and low maintenance requirements.

Metal roofs can last for up to 30 years or more with proper installation and maintenance.

There are several types of metal roofing materials available, including galvanized steel, aluminum, and corrugated metal.

Galvanized steel is a cost-effective option that can withstand harsh weather conditions.

A well-installed metal roof can save homeowners money on energy bills by reflecting sunlight and heat.

Before you start installing a metal shed roof, it's essential to prepare the existing shed structure. This involves clearing the roof of any old roof coverings and debris, which will give you a clean surface to work with.

Removing old shingles and debris requires some care, so use a pry bar or shovel to gently lift the shingles and remove the nails or screws holding them in place. Dispose of all debris properly and responsibly.

Inspecting the shed structure is a crucial step that's often overlooked. Check all the structural components, like the rafters, decking, and joints, for any signs of wear and damage.

Calculating the square footage of your roof is a crucial step in planning a successful metal roofing installation.

First, measure the length and width of your roof in feet.

To get the total square footage, multiply these two numbers together.

Keep in mind that corrugated metal roofing typically comes in 26-inch panels, so you'll need to divide the total square footage of your roof by the square footage of each panel to determine the number of panels needed.

You'll also need to calculate the total linear footage of ridge cap and eaves trim needed for your roof.

Be sure to add extra material for cutting and waste.

The materials needed for your metal roofing installation may include metal panels, ice and water shield, roofing nails, eave trim, gable trim, ridge cap, sidewall flashing, self-tapping roofing screws, metal roofing sealant, inside foam closure strips, outside foam closure strips, butyl tape, and roofing vent boots.

The lifespan of your shed roof is governed by two key factors: the local atmospheric environment and the steel sheets' corrosion protection system. This is crucial to know, as it directly affects how long your shed roof will last.

The lifespan of metal shed roofing is measured in the 'time to first maintenance'. This is the point at which you'll need to start thinking about repairing or replacing your roof.

In areas with high levels of pollution or salt in the air, the lifespan of your shed roof can be significantly reduced. Corrosion from these elements can weaken the steel sheets and cause them to fail.

A well-designed corrosion protection system can make a huge difference in the lifespan of your shed roof. This can include things like a protective coating or a specialized steel alloy.

Here are some examples of how different corrosion protection systems can affect the lifespan of your shed roof:

By choosing the right corrosion protection system for your shed roof, you can significantly extend its lifespan and avoid costly repairs down the line.

Choosing a Roof Profile is a crucial decision when it comes to your metal shed roof. You have two main options: 0.5mm (24swg) and 0.7mm (22swg) thicknesses.

The heavier 22swg material is the most widely used, with a typical purlin spacing of 1.0m. This makes it a great choice for larger sheds. It's also worth noting that this material is slightly more expensive than the lighter option.

However, if you're on a tighter budget, the 24swg material might be the way to go. It's cheaper and can be used on smaller buildings, but keep in mind that it's more prone to damage and requires closer purlin spacing (0.6m).

When choosing a metal roofing profile, the first decision is the material thickness. In the UK, roofing sheets are available in two thicknesses: 0.5mm and 0.7mm.

The heavier 0.7mm material is the most widely used, with a typical purlin spacing of 1.0m.

The lighter 0.5mm material is suited for domestic scale sheds and is slightly cheaper than the 0.7mm sheets.

However, the lighter material is more prone to damage and purlins are needed at closer centres, typically 0.6m.

You might want to weigh up whether the cost saving of the lighter material is really worth your while.

Choosing the right color for your roof can be a bit overwhelming, but there are many options to choose from. Metal building colors offer a wide range of choices.

You can explore the details on metal roof color options on our page dedicated to metal building colors.

PBR panels are a type of metal paneling product that can be used for various applications, including agricultural, commercial, industrial, and residential settings.

They're highly customizable to suit any need, with options for different coatings, color choices, and substrates.

PBR panels are made of 26-gauge steel and are a type of through-fastened roofing panel.

The panels overlap where they meet, providing a larger joint that offers better leak protection against wind-driven rain or snow.

This overlap also protects against snow or wind load and the weight of anyone walking on the roof.

PBR panels are a popular choice for buildings with high aesthetic value, such as office, community, and commercial structures.

Concealed fastened roof panels are a popular choice for commercial and industrial low-rise metal buildings. They're installed on approximately 50% of all new buildings of this type.

The unique design of concealed fastened roof panels provides maximum weather-proofing. There are no screws on the outside penetrating the panels, which means they're less prone to leaks.

The overlap seam is above the roof deck, further enhancing weather-proofing. This design also makes it easier to install the panels, as all attachment is underneath the panel itself.

The attachment system uses concealed steel clips with movable tabs. These clips are fastened to the purlins, while the roofing sheets are rolled around the tabs and can slide with the tabs relative to the clip bases.

Here are the pros and cons of concealed fastened roof panels:

However, concealed fastened roof panels come with a higher price tag. They can be twice as much or more compared to through-fastened roofs, making them a more expensive option.

To install a metal shed roof, you'll want to start by laying out and positioning the first panel at the eave line, ensuring it overhangs the edge of the shed by at least 4 inches. This overhang will help divert any water away from the structure.

The first metal panel should be secured in place using 1 ½-inch wood screws, tightened just enough to hold the panel in place without dimpling the metal. It's essential to add screws to both the outside edge and the bottom of the panel, spaced approximately every 8 inches.

To ensure a seamless, waterproof roof, overlap each metal panel adequately, maintaining a minimum overlap of six inches for corrugated metal roofing. This will prevent water from seeping under the panels and into the shed.

Explore further: Shed Roof Drip Edge

Here are the key steps to secure the panels with roofing nails and sealant tape:

Having the right tools is crucial for a smooth roof installation. You'll need a hammer, tape measure, snips, rivets, and a caulking gun.

Snips are ideal for cutting metal sheets, while rivets are useful for securing metal pieces in place. A caulking gun will help seal any gaps to prevent water leakage.

A sturdy ladder is also essential to reach the roof and move around safely. You'll want to make sure it's sturdy and secure.

An adjustable-torque handheld drill is necessary for driving screws or fastening metal pieces. This drill allows you to select the torque setting, which ensures the screws aren't overdriven and the metal panels remain intact.

For cutting metal panels, a malco turboshear is a recommended tool. It's designed for cutting corrugated roofing materials and can be fitted to the end of your drill.

To install a metal roof, start by laying out and positioning the first panel at the eave line, ensuring it overhangs the edge of the shed by at least 4 inches. This overhang will help divert water away from the structure and prevent seepage underneath the panel.

Secure the first panel in place using 1 ½-inch wood screws, tightening them just enough to hold the panel without dimpling the metal. A general rule of thumb is to stop tightening when you feel resistance.

To ensure the panel is properly secured, add screws to both the outside edge and the bottom, spaced approximately every 8 inches. This will prevent the metal panel from buckling, especially in windy conditions.

Next, overlap each subsequent panel by at least six inches to maintain a waterproof seal. Use roofing nails approximately six inches apart, inserted through the flat metal surface, to secure the overlapping edge.

After inserting the roofing nails, press sealant tape over each nail head to waterproof the nail holes and prevent leakage. Continue positioning and overlapping the panels until you complete the roof surface.

To ensure a long-lasting and waterproof roof, it's essential to have the right tools on hand. You'll need snips for cutting metal sheets, rivets for securing metal pieces, and a caulking gun to seal any gaps.

Here's a list of tools you'll need for a smooth installation process:

Remember to choose the right underlayment for a residential or commercial project, as it serves as an extra weather resistance barrier and provides greater moisture protection.

Cutting metal roofing panels requires precision and care to prevent water from entering through the openings. You can use power shears or tin snips, but be sure to wear proper safety gear.

To cut holes in the metal panels, you'll need to use precision and care to ensure that no water can enter. Power shears or tin snips are suitable tools for this job.

If you need to cut a metal panel, you can't use a circular saw, as it's not designed for cutting corrugated roofing materials. A pair of tin snips could be used, but a malco turboshear is a better option.

A malco turboshear is a tool that fits on the end of your drill and is designed specifically for cutting corrugated roofing materials. It's a game-changer for this type of job.

The most basic malco turboshear model will only cut straight lines or curves to the left, so you'll need to plan your cuts carefully. The more expensive models will cut both ways, giving you more flexibility.

This tool will cut material up to 18 gauge (1.22mm), which is a significant advantage when working with metal roofing panels.

Here's an interesting read: How to Cut Rafters for Shed Roof

A metal shed roof consists of several key components, each playing a crucial role in its overall performance.

The metal roof panel is the primary component, available in various raised rib styles and profiles, including the Ag panel, box panel, and wavy profile, also known as "corrugated iron."

These profiles can vary in dimensions and characteristics, so it's essential to check with your supplier for specific requirements.

The Ag panel, commonly used on agricultural buildings in the USA, has dimensions based in feet and inches, while the box panel is widely available in the UK and Europe.

The ridge cap is another critical component, covering the join between the two sheets at the apex of a gable shed, and ideally, it should match the corrugations of the roof sheet.

A drip edge isn't essential with metal roofs, as the edge of the roof forms its own "drip", but it's still required to ensure proper water discharge.

Here's a brief overview of the common metal shed roofing profiles:

An underlayment, such as tar paper or building paper, can be used to prevent condensation on the underside of the roof, especially in damp climates.

When installing corrugated metal roofing on your shed, you'll need some essential materials to get the job done.

You'll need metal to metal fasteners to secure the metal panels in place.

Silicone sealant is also a must-have to ensure a watertight seal between the metal panels.

Calculating the square footage of your shed is crucial to determine the right amount of materials to purchase.

A metal roof is made up of several key components, each playing a crucial role in its overall performance. The main components of a metal roofing system are the metal roof panel, ridge cap, roof verge trim, drip edge, and underlayment.

The metal roof panel is the most visible part of the system, and it comes in a variety of raised rib styles. Panels are formed from sheet steel that's been galvanized, shaped, and coated for protection and color.

You'll find different types of metal roof panels, such as the Ag panel, box panel, and wavy profile, each with its own characteristics and requirements. For example, the Ag panel is commonly used on agricultural buildings in the USA, while the box panel is widely available in the UK and Europe.

The ridge cap is a critical component that covers the join between two sheets at the apex of a gable shed. It's essential to ensure that the corrugations match with those of the roof sheet, but in many cases, this isn't a requirement.

A drip edge isn't always necessary with metal roofs, as the edge of the roof forms its own 'drip'. However, it's still important to ensure that the roof sheeting cantilevers over the shed wall so that water can discharge into the roof gutter.

Underlayment is a material used to prevent condensation on the underside of the roof, particularly in damp climates. A good option is a waterproof and long-lasting material like Tyvek, which can catch drips of condensation and direct them out of the building at the eaves.

Here's a quick rundown of the main components of a metal roofing system:

Securing the panels is a crucial step in installing a corrugated metal roof. You'll need to use the right fasteners, such as roofing screws, to secure the metal panels to your shed's surface.

Roofing nails aren't used for metal roofs, so make sure to use the recommended roofing screws instead. Special roofing screws are designed to provide a secure hold on the metal sheets.

For your interest: Secure Decorations

To secure the panels, you'll need to attach them using screws at regular intervals over the entire length of the roof. Consider the expansion and contraction of the metal due to weather changes.

You have a choice with where to fit the screws: in the trough of the metal profile or on the raised ridge. Fixing through the ridge can be a good option, but be sure to check the depth of the profile and use the correct length of screw.

Here are some tips for securing the panels:

A good seal between the panel and the screw is easy to do after a couple of attempts to learn the correct torque to apply with your screw gun.

Trimming excess material from your corrugated metal roof panels is a crucial step in achieving a clean and professional look.

To trim excess material, you'll need a speed square and tin snips. It's essential to take precise measurements to avoid trimming too much material, which can lead to leaks and other issues.

Measure and mark the areas that require trimming using a speed square. Place the metal panels on a flat, stable surface, such as a workbench or sawhorse, to get a clean cut without damaging the panel's surface or bending it out of shape.

Using tin snips, make strategic cuts along the marked lines. Take your time and make sure the snips are cutting through the metal smoothly and evenly.

Wearing gloves is a must when trimming metal to prevent injuries or cuts from sharp edges. The edges of the metal can be sharp, and gloves will help you avoid accidents.

After trimming, inspect the edges of the metal for any burrs or sharp edges. If you notice any, use sandpaper to dull them down. Dulling exposed edges or burrs will prevent injury and protect against rust.

A little extra care when trimming excess material can make a big difference in the final result.

A zinc coating, also known as galvanising, is the basis of the corrosion protection system that influences the life of a shed roof. This coating creates a sacrificial layer on the steel that protects the bare steel beneath.

A typical coating thickness is 275 g/m², which provides a good balance between protection and cost. However, this layer of zinc is gradually worn or washed away when it's exposed to the elements.

If the zinc coating is not protected, the steel will begin to rust, significantly reducing the lifespan of the roof. A typical polyester paint system can extend the time to first maintenance in a coastal environment from 1-5 years up to 10-15 years.

A PVC Plastisol coating is more durable and can give a time to first maintenance in a coastal environment of 15-25 years. It's essential to choose a paint colour that will help prolong the life of your roof.

Interestingly, light colours tend to last significantly longer than dark colours. A light colour can have a time to first maintenance twice that of a darker colour. This is because light colours reflect heat and suffer less thermal stress than dark colours.

Here's a comparison of the time to first maintenance for different paint systems and colours:

Corrugated metal roofing is a popular choice for sheds and homes due to its impressive durability. It can last for decades and withstand harsh weather conditions, including high winds, heavy rainfall, and extreme temperatures.

One of the most significant advantages of corrugated metal roofing is its recyclability. Metal roofing materials are highly recyclable and can be repurposed or reused at the end of their lifespan.

Corrugated metal roofing offers several style options, making it an aesthetically pleasing choice for homeowners. Metal roofs come in different colors and styles, including traditional standing seam panels and metal shingles.

A corrugated metal roof can provide a higher return on investment for homeowners. This type of roofing material is nearly maintenance-free, meaning you won't need to spend money on frequent repairs or replacements.

Here are some key benefits of corrugated metal roofing at a glance:

A corrugated metal roof can also help decrease ambient roof temperature, extend the service life of your roof, attic, and supporting infrastructure, and make your structure more energy-efficient.