Installing a tin roof over existing shingles can be a great way to give your home a new look and protect it from the elements. However, it’s important to do the job correctly to avoid any problems down the road. In this article, we’ll walk you through the steps on how to put a tin roof over shingles, including how to prepare the roof, install the tin panels, and finish the job. By following these instructions, you can ensure that your new tin roof will last for many years to come.
Before you begin, it’s important to make sure that your roof is in good condition. If there are any damaged or missing shingles, you’ll need to repair them before you can install the tin roof. Once the roof is in good condition, you can start by removing any old flashing or other roofing materials that may be in the way. Then, you’ll need to install a layer of roofing felt over the shingles. This will help to protect the shingles from the elements and provide a smooth surface for the tin panels.
Once the roofing felt is in place, you can start installing the tin panels. Tin panels are typically attached to the roof using screws or nails. It’s important to use the correct type and size of fasteners for the type of tin panels you’re using. Once the tin panels are installed, you’ll need to seal the seams between the panels using a roofing sealant. This will help to prevent water from leaking into the roof. Finally, you can install any necessary trim or flashing to finish the job.
Assessing the Condition of Existing Shingles
Before installing a metal roof over shingles, it’s crucial to thoroughly evaluate the condition of the existing shingles to ensure a successful and long-lasting installation. Here are some key factors to consider:
Age and Condition of Shingles
Inspect the shingles for signs of wear and tear that may affect the stability of the new metal roof. Look for:
– Curled, cracked, or missing shingles
– Granules loss, resulting in exposed asphalt
– Rot or water damage
– Loose or missing nails
– Sagging or uneven roof areas
Roofing Underlayment
Examine the condition of the roofing underlayment, which acts as a moisture barrier between the shingles and the roof deck. Check for:
– Rips, tears, or holes
– Deterioration or crumbling
– Proper installation and overlap
Slope and Surface
Assess the slope and surface of the roof. A metal roof requires a minimum slope for proper drainage. Check for:
– Flat or low-slope areas that may retain water
– Uneven surfaces or protrusions
– Valleys, hips, and ridges that may require special attention
Flashing
Inspect the flashing around chimneys, vents, and other roof penetrations. Ensure that the flashing is:
– Secure and watertight
– Well-sealed to prevent leaks
– Made of a durable material
By carefully assessing these factors, homeowners can make informed decisions about whether their existing shingles can support a metal roof installation. If any significant issues are identified, it may be necessary to repair or replace the shingles before proceeding with the metal roof installation.
Preparing the Roof Surface for Tin Installation
Before you can install a tin roof over shingles, you need to prepare the roof surface. This involves removing any existing shingles, as well as any nails or staples that may be holding them in place. Once the roof is clear, you need to inspect it for any damage. If you find any damaged areas, you will need to repair them before you can install the tin roof.
Inspecting the Roof
Once you have removed the shingles, you need to inspect the roof for any damage. This includes looking for any holes, cracks, or missing shingles. You should also check the flashing around the chimneys and vents to make sure that it is in good condition. If you find any damage, you will need to repair it before you can install the tin roof.
Here is a table of some of the most common types of roof damage and how to repair them:
| Type of Damage | How to Repair |
|---|---|
| Holes | Patch the holes with roofing cement or flashing. |
| Cracks | Seal the cracks with roofing cement or caulk. |
| Missing shingles | Replace the missing shingles with new ones. |
| Damaged flashing | Replace the damaged flashing with new flashing. |
Selecting the Appropriate Gauge and Type of Tin
Choosing the right gauge and type of tin is crucial for a durable and aesthetically pleasing tin roof.
Gauge
Tin roofing is available in various gauges, which refer to its thickness. Thicker tin is more durable but heavier and more expensive. For residential applications, 26- or 28-gauge tin is typically recommended. Here’s a table summarizing the differences:
| Gauge | Thickness (Inches) | Weight (Pounds per Square Foot) |
|---|---|---|
| 24 | 0.024 | 1.25 |
| 26 | 0.018 | 0.90 |
| 28 | 0.015 | 0.75 |
Type
There are two main types of tin roofing: terne-coated steel and aluminum-zinc alloy. Each has its own advantages and drawbacks:
- Terne-coated steel is a traditional material that has been used for centuries. It’s made from steel that’s coated with a thin layer of tin. Terne-coated steel is durable, corrosion-resistant, and relatively inexpensive. However, it can be noisy when raining and can develop rust spots over time.
- Aluminum-zinc alloy is a newer material that’s made from an alloy of aluminum and zinc. It’s lighter than terne-coated steel, more corrosion-resistant, and doesn’t make as much noise when raining. However, it’s more expensive and can be more difficult to install.
Factors to Consider
When choosing the gauge and type of tin, consider the following factors:
- Climate: In areas with severe weather conditions, a thicker gauge tin may be necessary.
- Budget: Terne-coated steel is generally more affordable than aluminum-zinc alloy.
- Aesthetics: Terne-coated steel has a more traditional appearance, while aluminum-zinc alloy has a more modern look.
Cutting and Shaping the Tin Panels
Once you’ve measured and marked the tin panels, you’ll need to cut them to size. Use tin snips or a circular saw with a metal cutting blade to make clean, straight cuts. When cutting, be sure to wear safety glasses and gloves to protect yourself from sharp edges.
After cutting the panels, you may need to shape them to fit around obstacles, such as chimneys or skylights. To do this, use a tin brake or a pair of pliers to bend the panels into the desired shape. Be careful not to over-bend the panels, as this can weaken the metal.
Once the panels are cut and shaped, you’re ready to install them on the roof. Start by nailing the bottom edge of the first panel to the roof deck. Then, overlap the next panel over the first panel by 2 inches and nail it down. Continue in this manner, overlapping each panel by 2 inches until you reach the top of the roof.
As you’re installing the panels, be sure to seal the seams with roofing cement to prevent leaks. You can also use a ridge cap to cover the seam at the peak of the roof.
Tips for Cutting and Shaping Tin Panels
- Use sharp tin snips or a circular saw with a metal cutting blade.
- Wear safety glasses and gloves to protect yourself from sharp edges.
- Be careful not to over-bend the panels, as this can weaken the metal.
- Start by nailing the bottom edge of the first panel to the roof deck.
- Overlap the next panel over the first panel by 2 inches and nail it down.
- Continue in this manner, overlapping each panel by 2 inches until you reach the top of the roof.
- Seal the seams with roofing cement to prevent leaks.
- Use a ridge cap to cover the seam at the peak of the roof.
Installing the Tin Panels: Starting at the Bottom
1. Start at the Edge
Begin by aligning the first tin panel at the bottom edge of the roof, ensuring it overhangs the edge by approximately 2 inches. Use roofing nails to secure it every 12 inches along the bottom edge.
2. Install Starter Strips
Install starter strips along the bottom edge of the roof, which will help keep the tin panels in place. Nail the starter strips into the roof deck using roofing nails spaced 6 inches apart.
3. Overlap the Panels
Overlap the next tin panel by a minimum of 6 inches, ensuring the overlapped section is against the prevailing wind direction. Drive roofing nails through the overlapped section, spacing them 12 inches apart.
4. Install Side Laps
Install side laps by fastening tin panels together with roofing nails. Overlap the panels vertically by 4 inches and nail them together every 12 inches, creating a weathertight seal.
5. Seal the Joints
To prevent water infiltration, seal all joints and seams using a high-quality roofing sealant. Apply a generous bead of sealant along the edges and overlaps, then smooth it out with a putty knife. Allow the sealant to dry completely before moving on.
| Joint Type | Sealing Method |
|---|---|
| Horizontal Overlaps | Apply sealant along the overlapped section |
| Vertical Side Laps | Seal between the panels and the side laps |
| Roof Edges | Caulk around the edges of the tin roofing |
Overlapping and Sealing the Tin Panels
Properly overlapping and sealing the tin panels is essential for ensuring a leak-proof and durable roof. Follow these steps carefully:
1. Overlapping the Panels
- Start at the bottom edge of the roof and work your way up.
- Overlap each row of panels by at least 6 inches.
- Ensure that the horizontal seams overlap vertically by at least 12 inches.
2. Installing the Center Seam
Use tin snips to cut a V-shape into the center of the overlapping panels. This creates a channel for the sealant to flow into.
3. Applying Sealant
Apply a generous bead of roofing sealant into the V-shaped channel. Use a caulking gun for precise application.
4. Crimping the Seam
Use a seaming tool to crimp the edges of the overlapping panels together. This will help seal the seam and prevent leaks.
5. Applying Silicone Caulk
Apply a bead of silicone caulk along the entire length of the crimped seam. This will provide an additional layer of protection against moisture penetration.
6. Flashing the Seams
To ensure maximum protection, install a layer of flashing over the crimped and sealed seams. The flashing should be made of a waterproof material such as galvanized steel or aluminum and should overlap the seams by at least 6 inches on all sides.
| Flashing Material | Recommended Overlap |
|---|---|
| Galvanized Steel | 6 inches |
| Aluminum | 6 inches |
Flashing and Trim Work
Flashing
Flashing refers to thin sheets of metal used to seal the roof’s edges, preventing water from penetrating. It’s typically made of galvanized steel, aluminum, or copper and comes in various shapes and sizes to fit different roof components.
Step 1: Install Base Flashing
Secure the base flashing to the roof’s edge, where the shingles meet the fascia boards. Overlap the flashing at the corners and seal it with caulk.
Step 2: Install Step Flashing
Cut step flashing into pieces that fit the spacing between the shingles. Slide the flashing under the shingles and over the base flashing. Seal the joints with caulk.
Step 3: Install Ridge Cap Flashing
Fit the ridge cap flashing over the ridge of the roof. Overlap the panels and seal them with adhesive.
Step 4: Create Custom Flashing
In some cases, you may need to create custom flashing pieces for complex rooflines or penetrations. Use a metal brake or snips to cut the flashing to the desired shape.
Trim Work
Trim work refers to decorative elements used to enhance the roof’s appearance and protect its edges from damage.
Step 1: Install Facia Boards
The fascia boards are installed around the roof’s perimeter, covering the edges of the roof sheathing and shingles.
Step 2: Install Soffit Vents
Soffit vents are installed on the underside of the eaves to allow air to circulate through the roof’s attic space.
Step 3: Add Exterior Corner Trim
Exterior corner trim is installed at the corners of the roof to provide additional protection and a seamless appearance.
Step 4: Choose Decorative Trim
Various decorative trim options are available, such as molding, gingerbread, and finials. These elements can enhance the roof’s aesthetic appeal.
Painting or Coating the Tin Roof
Painting or coating your tin roof can enhance its longevity, protect it from the elements, and improve its aesthetic appeal. Here are some detailed steps to follow:
1. Cleaning the Roof
Thoroughly clean the roof to remove dirt, debris, and any existing paint or coating. Use a pressure washer or a stiff brush with a cleaning solution.
2. Preparation
Inspect the roof for any damage or rust spots. Repair any damages and sand down any rust spots.
3. Primer Application
Apply a metal-specific primer to the roof. This will provide a good base for the paint or coating to adhere to.
4. Paint or Coating Selection
Choose a paint or coating designed specifically for metal roofs. Consider factors such as rust resistance, UV protection, and color.
5. Application Techniques
Use a brush or roller to apply the paint or coating. Apply even coats and avoid leaving any streaks or drips.
6. Drying Time
Allow the paint or coating to dry according to the manufacturer’s instructions. Drying times may vary depending on the product and weather conditions.
7. Multiple Coats
For optimal protection and durability, apply multiple coats of paint or coating. Sand lightly between coats to ensure a smooth finish.
8. Safety Precautions
Wear appropriate safety gear, including gloves, eye protection, and a dust mask, when handling the paint or coating. Ensure adequate ventilation when working with solvent-based products.
| Gutter Material | Pros | Cons |
|---|---|---|
| Copper | Durable, corrosion-resistant, aesthetically pleasing | Expensive, requires soldering |
| Steel | Strong, affordable, easy to install | Can rust if not properly protected |
| Aluminum | Lightweight, corrosion-resistant, easy to shape | Can be more expensive than steel |
Maintaining and Repairing the Tin Roof
Regular maintenance is crucial to extend the lifespan of a tin roof. Here are some essential steps to keep it in good condition:
- Clean the Roof: Remove debris, dirt, and mold by gently washing the roof with a mild detergent and soft brush.
- Inspect the Roof: Regularly check for any damage, such as leaks, loose sheets, or rust spots.
- Repair Leaks: If leaks are detected, locate the source and use sealant or patching materials to repair them promptly.
- Replace Damaged Sheets: If sheets are damaged beyond repair, they should be replaced with new ones.
- Touch Up Paint: Touch up any scratched or peeling paint to prevent rust and corrosion.
- Inspect and Clean Gutters: Make sure gutters are free of debris and functioning properly to prevent water damage.
- Trim Overhanging Trees: Remove branches that may damage the roof during storms or high winds.
- Walk with Caution: Avoid walking on the roof unless necessary, as excessive foot traffic can cause damage.
- Avoid Acidic Cleaners: Use mild cleaning agents to avoid damaging the protective coating on the tin.
- Annual Inspection: Schedule an annual inspection by a roofing professional to assess the roof’s condition and identify any potential issues.
| Maintenance Frequency | Task |
|---|---|
| Monthly | Clean roof and inspect for leaks |
| Annually | Repair leaks, replace damaged sheets, and touch up paint |
| Yearly | Professional roof inspection |
Safety Precautions for Tin Roof Installation
Installing a tin roof over shingles requires careful preparation and adherence to safety guidelines. To ensure a successful and hazard-free installation, follow these comprehensive safety precautions:
-
Install Safety Equipment:
Wear appropriate safety gear, including a hard hat, safety glasses, gloves, and sturdy work boots, to protect against falling debris and sharp edges.
-
Inspect the Roof:
Before beginning installation, thoroughly inspect the roof for any structural damage, loose shingles, or potential hazards.
-
Secure the Ladder:
Use a sturdy extension ladder with a wide base and tie it off securely to prevent slipping or falling.
-
Use Fall Protection:
Install fall protection equipment, such as a safety harness or a roof anchor point, if working at heights.
-
Avoid Power Lines:
Maintain a safe distance from power lines and avoid any contact with them.
-
Check Weather Conditions:
Plan installation during favorable weather conditions, avoiding extreme heat, rain, or strong winds.
-
Wear Protective Clothing:
Wear long sleeves and pants to protect your skin from metal shavings and sharp edges.
-
Handle Materials Safely:
Use proper lifting techniques to move tin roof panels and other heavy materials to prevent injuries.
-
Secure Tools and Equipment:
Keep all tools and equipment in a designated area to prevent them from falling or being knocked over.
-
Follow Manufacturer Instructions:
Carefully read and follow the manufacturer’s installation instructions for the tin roof and any associated materials.
How to Put a Tin Roof Over Shingles
Installing a tin roof over shingles is a great way to extend the life of your roof and add a stylish touch to your home. However, it’s important to note that this is a complex project that should only be undertaken by experienced roofers. Here are some simple steps to follow:
- Remove the existing shingles.
- Install a layer of roofing felt over the bare roof deck.
- Install the metal panels over the roofing felt, starting from the bottom edge of the roof and working your way up.
- Secure the metal panels with roofing screws.
- Install flashing around the edges of the roof and any penetrations, such as chimneys or skylights.
- Trim the excess metal and caulk around the edges of the roof.
People Also Ask About How to Put a Tin Roof Over Shingles
Do I need to remove the existing shingles before installing a tin roof?
Yes, it is important to remove the existing shingles before installing a tin roof. This will ensure that the new roof is properly installed and will not be damaged by the old shingles.
Can I install a tin roof over damaged shingles?
No, you should not install a tin roof over damaged shingles. The damaged shingles could compromise the integrity of the new roof and lead to leaks.
How long will a tin roof last?
A tin roof can last for 50 years or more with proper maintenance.
