The roof of your house is its first line of protection against the weather. It protects you from the sun, wind, rain, and snow while preserving a cozy living space and your possessions. However, a roof can only serve its intended purpose if it is placed correctly. The process of installing a new roof or replacing an old one on a building is known as roofing installation. This important project requires careful planning, appropriate material selection, and precise execution of each phase. This summary will go over how to install a roof, look at the many materials that are available, stress the value of correct installation, and provide advice on how to choose a reliable roofing contractor.

process of roofing installation

The Process of Roofing Installation


Project Planning:

  • Consultation and Needs Assessment: Before any work begins, a qualified roofing contractor will meet with the homeowner to discuss their needs and expectations. This includes factors like the desired roof style, budget considerations, and any specific concerns about the existing roof.
  • Roof Design and Material Selection: Based on the consultation and a thorough inspection of the roof structure, the contractor will present the homeowner with different design options and recommend suitable roofing materials. Factors influencing design selection include roof pitch, local building codes, and desired aesthetics. Material selection will depend on factors like budget, desired lifespan, durability needs, and compatibility with the roof structure. The contractor should present the pros and cons of various options like asphalt shingles, metal roofing, and tile roofing, and discuss factors like weight, fire resistance, maintenance requirements, and noise reduction.
  • Cost Estimates and Timeline: Once the design and materials are finalized, the contractor will provide a detailed estimate outlining the total project cost. This should include the cost of materials, labor, permits (if required), disposal fees for old roof materials, and any unexpected costs that may arise. The estimate should also include a clear timeline for the project, outlining the expected start and completion dates.
  • Permitting: Depending on the location and scope of the project, obtaining a permit from the local building department may be necessary. The roofing contractor will typically handle the permit application process, ensuring all required documents and inspections are completed.

Site Preparation:

  • Safety Measures: Before any demolition work begins, the contractor should prioritize safety by setting up a proper working area. This includes erecting scaffolding for safe access to the roof, establishing clear fall protection zones, and ensuring proper ventilation to avoid dust inhalation when removing old materials.
  • Existing Roof Removal (if applicable):
  • Tear-Off: The process of removing the existing roof is often referred to as a “tear-off.” The contractor will carefully remove shingles or tiles using pry bars and roofing hooks. Safety measures like using a dumpster chute and keeping bystanders clear of the work area are crucial.
  • Underlayment Removal: Once the shingles or tiles are removed, the old underlayment is also removed and disposed of properly.
  • Roof Sheathing Inspection: After the old roof is completely removed, the underlying roof sheathing (typically plywood or oriented strand board) is thoroughly inspected for signs of moisture damage, rot, or structural weaknesses. Any damaged sheathing needs to be repaired or replaced before installing the new roof.
  • Debris Removal and Disposal: A significant amount of debris will be generated during the tear-off process. The roofing contractor is responsible for safely removing and disposing of all old roofing materials according to local regulations. This may involve separating recyclable materials like metal flashing from materials destined for landfills.
  • Asbestos Inspection (if necessary): If the existing roof was installed before the late 1970s, there’s a potential presence of asbestos-containing materials in the underlayment or shingles. The contractor will recommend an asbestos inspection by a certified professional before any demolition work begins. If asbestos is found, specific abatement procedures are required for safe removal and disposal.

Roof Deck Inspection:

  • Following the tear-off (if applicable) or a thorough inspection of the existing roof deck, its condition needs to be carefully assessed. The roof deck is the structural base that supports the underlayment and roofing materials. The contractor will look for signs of moisture damage, warping, rot, or insect infestation. They will also check for sufficient nail penetration from the previous roof (if applicable) to ensure the structural integrity of the deck. Any weak or damaged areas will require repairs or replacement of the roof sheathing before proceeding with the new roof installation.

Installation Phases:

Underlayment Installation:

  • Purpose: Underlayment acts as a secondary barrier against water infiltration. It protects the roof deck from moisture damage caused by wind-driven rain or ice dams that may occur under certain weather conditions.

Types of Materials:

  • Felt Underlayment (Asphalt Saturated Felt): A traditional choice, felt is affordable and easy to install. However, it absorbs moisture over time and can lose its effectiveness.
  • Synthetic Underlayment: Newer synthetic underlayments are made from materials like fiberglass or non-woven polyester. They offer superior water resistance, and breathability, and can last longer than felt. They come in various thicknesses depending on the desired level of protection.

Installation Process:

  • Underlayment is typically rolled out horizontally across the roof deck, starting at the eaves (the lower edge of the roof) and working upwards.
  • Overlaps between rolls (usually 4-6 inches) and at the ends (seams) are sealed with waterproof tape to create a continuous water barrier.
  • The underlayment is secured with staples or roofing nails along the edges and at defined intervals across the surface.
  • Special attention is paid to valleys (interior angles where two roof slopes meet) and around roof penetrations, ensuring proper sealing with flashing materials (discussed below).

Flashing Installation:

  • Importance: Flashing is a thin sheet metal material installed around roof penetrations like chimneys, vents, skylights, and around walls where the roof meets the siding.
  • Flashing creates a watertight seal and prevents leaks at these vulnerable points on the roof.

Types of Flashing:

  • Step Flashing: Used around walls where the roof meets the siding. Step flashing consists of overlapping pieces that create a watertight channel, directing water away from the wall.
  • Base Flashing: Installed directly on the roof deck and under the shingles/tiles, forming the primary water barrier around chimneys and other penetrations.
  • Counter Flashing: Installed over the base flashing and shingles/tiles, creating a secondary water barrier and capping the step flashing.
  • Valley Flashing: A specialized type of flashing installed in the valleys of the roof to channel water and prevent leaks at these intersections.

Installation Process:

  • Flashing installation involves cutting the metal sheets to size and shaping them to fit around the specific roof penetration.
  • Flashing pieces are overlapped and sealed with waterproof sealant or soldered together (for copper flashing) to ensure a watertight connection.
  • Nails driven through the flashing secure it to the roof deck and underlying structure.

Shingle or Tile Installation (depending on material choice): 

Shingle Options:

  • Asphalt Shingles (Most Common):
    • Pros: Affordable, easy to install, wide variety of styles and colors available.
    • Cons: Shorter lifespan (15-30 years) compared to other options, susceptible to wind damage and high heat.
  • Metal Shingles:
    • Pros: Durable, fire-resistant, long lifespan (40-70 years), low maintenance.
    • Cons: Higher cost than asphalt, can be noisy during heavy rain, may dent in hailstorms.
  • Slate Shingles:
    • Pros: Beautiful natural aesthetic, extremely long lifespan (over 100 years), fire-resistant.
    • Cons: Very expensive, heavy (requires strong roof structure), fragile, and requires skilled installation.
  • Wood Shingles:
    • Pros: Classic aesthetic, good insulation properties, environmentally friendly (renewable resource).
    • Cons: High cost, requires regular maintenance (staining/sealing), fire risk (depending on treatment).

Ridge Cap and Ventilation

Ridge Cap: Sealing the Roof’s Peak 

Purpose: A ridge cap is a covering placed along the peak of the roof, where two sloping roof planes meet. It serves several important functions:

  • Water Protection: The primary function of a ridge cap is to prevent water infiltration at the peak. Rain can blow sideways under shingles, and a properly installed ridge cap creates a watertight seal, preventing leaks and potential water damage to the roof deck and attic below.
  • Wind Uplift Resistance: Strong winds can exert significant uplift pressure on shingles, potentially causing them to tear or blow off. A ridge cap helps secure the shingles at the peak and reduces the risk of wind uplift.
  • Finished Appearance: Ridge caps provide a clean and finished aesthetic look to the roofline, enhancing the overall curb appeal of the building.

Types of Ridge Caps:

  • Shingle Ridge Cap: This is the most common type, typically made from the same material as the asphalt shingles used on the roof. It involves folding and overlapping the top row of shingles at the peak to create a continuous cap.
  • Metal Ridge Cap: Made from galvanized steel, aluminum, or copper, metal ridge caps offer superior durability and weather resistance compared to shingle caps. They come in various styles and colors to complement different roof materials.
  • Vented Ridge Cap: This type of ridge cap incorporates a built-in ventilation channel that allows air to flow out of the attic space. This can be beneficial for promoting proper roof ventilation (discussed further below).

Installation: Installing a ridge cap requires careful attention to ensure a watertight seal and proper ventilation (if using a vented cap). Shingle ridge caps require skilled craftsmanship to achieve a neat and even fold. Metal ridge caps are typically fastened to the roof deck using nails or screws.

Roof Ventilation: Importance and Methods

Proper roof ventilation is crucial for a healthy and long-lasting roof system. It helps to:

  • Reduce Heat Buildup: During hot weather, sunlight can heat up the attic space significantly. Ventilation allows hot air to escape, reducing attic temperatures and preventing heat-related damage to shingles and other roof components.
  • Prevent Moisture Problems: Moisture can build up in the attic due to condensation, especially during cold weather. Proper ventilation helps to remove moisture-laden air, preventing mold growth, rot, and other moisture-related issues within the roof structure.
  • Improve Energy Efficiency: By reducing heat buildup in the attic, proper ventilation can help to lower cooling costs in the summer.

There are two main methods for achieving proper roof ventilation:

  • Intake Vents: These vents are installed at the eaves (the lower edge of the roof where it meets the wall) and allow cool air to enter the attic space.  There are various types of intake vents, including soffit vents (installed under the eaves) and rake vents (installed along the sloped edge of the roof).
  • Exhaust Vents: These vents are located at the highest point of the roof and allow hot, moist air to escape. There are several types of exhaust vents:
  • Ridge Vents: These vents are installed along the peak of the roof under the ridge cap. They create a continuous airflow channel that allows hot air to escape efficiently.
  • Power Vents: These are electrically powered vents that use a fan to actively draw out hot air from the attic. They are particularly effective in attics with limited natural ventilation.
  • Wind Turbine Vents: These vents use wind power to rotate a turbine, drawing air out of the attic. They are a good option for areas with consistent winds.


Final Inspection:

A thorough final inspection by both the roofing contractor and the homeowner is crucial to ensure a successful roofing project. This inspection should be conducted meticulously and address all aspects of the new roof. Here’s a breakdown of key areas to examine:

  • Roof Shingles or Tiles:
    • Check for proper alignment and straight rows.
    • Ensure there are no missing, damaged, or improperly fastened shingles/tiles.
    • Verify all shingle/tile edges are sealed correctly to prevent water infiltration.
    • Inspect valleys and eaves for proper shingle/tile installation and flashing.
  • Flashing:
    • Meticulously examine all flashing around chimneys, vents, skylights, and other roof penetrations.
    • Ensure flashing extends far enough onto the roof surface and walls to create a watertight seal.
    • Verify all flashing seams are properly overlapped and sealed.
  • Roof Deck:
    • Briefly walk on accessible areas of the roof deck (with caution) to check for any protruding nails or uneven surfaces.
    • Look for signs of moisture damage on the roof deck that might have occurred during installation.
  • Valleys and Eaves:
    • Inspect valleys for proper drainage and ensure there are no gaps or debris buildup that could trap water.
    • Verify eaves are properly flashed and vented to prevent moisture buildup.
  • Ridge Cap and Ventilation:
    • Ensure the ridge cap is securely fastened and creates a watertight seal at the peak of the roof.
    • Check for proper ventilation installation, including intake and exhaust vents, according to building codes and manufacturer recommendations.
  • Gutters and Downspouts:
    • Verify gutters are securely fastened to the fascia board and pitched correctly for proper drainage.
    • Ensure downspouts are properly connected to gutters and extend far enough away from the foundation to prevent water pooling near the house.
  • Cleanup and Debris Removal:
    • Inspect the property surrounding the house for any leftover roofing materials, nails, or debris.
    • Ensure the contractor has removed all waste materials from the job site and disposed of them properly.

Additional Tips for Final Inspection:

  • Conduct the inspection on a dry, clear day with good lighting.
  • Don’t hesitate to ask the roofing contractor questions about any aspect of the installation.
  • Take pictures of the roof from various angles to document its condition after installation.
  • If any issues are identified during the inspection, have the contractor address them promptly before final payment is made.


Following the installation, the roofing contractor is responsible for leaving the property clean and free of debris. This includes:

  • Removing all leftover roofing materials, shingle scraps, nails, and other construction waste.
  • Cleaning up the work area around the house, including driveways, walkways, and landscaping.
  • Properly disposing of all waste materials according to local regulations.

Homeowner Responsibility:

While the contractor is responsible for major cleanup, homeowners can also play a role:

  • Rake nearby lawns and gardens to remove any fallen debris.
  • Inspect the property for any missed nails or debris that might pose a safety hazard.

By conducting a thorough final inspection and ensuring proper cleanup, homeowners can ensure a smooth transition to enjoying their new roof with peace of mind.

variety of roofing materials during an installation

Roofing Materials


Asphalt Shingles (most common):

  • Affordability and Ease of Installation: Asphalt shingles are the most budget-friendly roofing option. They are readily available and relatively simple to install, making them a popular choice for homeowners on a tight budget.
  • Styles and Colors: Asphalt shingles come in a wide variety of styles and colors, allowing homeowners to achieve a desired aesthetic look for their roofs. Common styles include 3-tab (flat), dimensional (textured), and architectural (multi-layered with a dimensional look). Colors range from classic black and brown to more modern options like grey and green.
  • Lifespan Limitations: While asphalt shingles offer a good value, their lifespan is generally shorter than other roofing materials. They typically last 15-30 years depending on factors like shingle quality, climate, and installation.

Metal Shingles:

  • Durability and Fire Resistance: Metal shingles are known for their exceptional strength and longevity. They can withstand harsh weather conditions like strong winds, hail, and even fire. Metal roofs typically have a lifespan of 40-70 years or even longer with proper maintenance.
  • Noise During Rain: One potential downside of metal roofs is their tendency to amplify noise during rainfall. This can be a concern for homeowners who are sensitive to noise.
  • Higher Cost: Metal shingles generally have a higher upfront cost compared to asphalt shingles. However, their extended lifespan and lower maintenance needs can make them a cost-effective option in the long run.
  • Material Options: Metal shingles come in various materials like steel, aluminum, zinc, and copper. Each material offers unique benefits and drawbacks in terms of durability, weight, and aesthetics. Steel is a popular choice for its affordability and strength, while copper offers a classic, long-lasting option with a distinctive patina that develops over time.

Other Shingle Options:

  • Slate Shingles:
    • Unique Aesthetics: Slate shingles offer a timeless and elegant look, often used on high-end homes. They are naturally beautiful and come in various colors depending on the region where the slate is quarried.
  • Drawbacks: Slate is a heavy material that requires a strong roof structure to support its weight. Additionally, slate shingles are very expensive and require specialized installation, making them a less common roofing option.

Wood Shingles:

  • Rustic Appeal: Wood shingles provide a natural and rustic aesthetic, particularly popular in cabins and historical restorations. They offer good insulation properties and can blend well with natural surroundings.
  • Maintenance Requirements: Wood shingles require regular maintenance, such as periodic staining or sealing, to ensure their longevity and prevent rot. They are also more susceptible to fire damage compared to other roofing materials.


Concrete Tiles:

  • Strength, Durability, and Longevity: Concrete tiles are known for their exceptional strength and durability. They are resistant to fire, wind, and impact, offering excellent protection for the building. Concrete tile roofs can last 50-100 years or even longer with proper maintenance.
  • Weight Considerations: Concrete tiles are a heavy material, requiring a roof structure specifically designed to support their weight. This can add to the overall cost of the roof installation.

Clay Tiles:

  • Classic Aesthetics and Fire Resistance: Clay tiles offer a classic Mediterranean aesthetic and are highly fire-resistant. They are also resistant to rot, insect damage, and harsh weather conditions.
  • Higher Cost and Brittleness: Clay tiles are a more expensive roofing option compared to asphalt or metal. They are also more brittle than concrete tiles and can crack if walked on or impacted by hail.

Flat Roof Materials:

  • Modified Bitumen: This is a popular choice for flat roofs due to its waterproofing capabilities and ease of application. It consists of asphalt sheets modified with polymers for increased flexibility and durability. Modified bitumen roofs typically last 15-20 years.
  • TPO Membranes (Thermoplastic Polyolefin): TPO membranes are a newer option for flat roofs, known for their energy efficiency and heat reflectivity. They are lightweight, easy to install, and offer good resistance to UV rays and punctures. TPO roofs typically last 20-30 years.

illustrates the importance of proper roof installation

Importance of Proper Installation

Avoiding Leaks and Damage: Improper installation can lead to a cascade of problems for your home, threatening its structural integrity, health, and overall value. Here’s a breakdown of some key issues:

  • Leaks: This is the most common consequence. Faulty flashing around chimneys, vents, or valleys, along with improperly sealed seams or shingle gaps, can create pathways for water intrusion. Leaking roofs can damage ceilings, walls, insulation, and even electrical systems.
  • Water Damage: Leaking water can lead to extensive water damage within the house. This can cause warping of floors, peeling of paint and wallpaper, and growth of mold and mildew, which can pose serious health risks.
  • Mold Growth: Mold thrives in damp environments. Leaks and improper ventilation caused by poor installation can create a breeding ground for mold, leading to respiratory problems, allergies, and other health issues for occupants.
  • Structural Issues: Over time, water damage can weaken the roof deck and supporting structures. This can lead to sagging ceilings, cracked walls, and even roof collapse in severe cases. Repairing these structural issues can be very expensive.
  1. Ensuring Roof Longevity:  A properly installed roof can last for decades, depending on the material and climate. Here’s how proper installation contributes to a long-lasting roof:
  • Attention to Detail: Qualified roofers ensure proper flashing installation, correct shingle or tile application techniques (e.g., proper overlap, nail placement), and adequate ventilation. These details prevent weaknesses that could lead to premature roof failure.
  • Material Integrity: Proper installation minimizes damage to roofing materials during the process. This ensures the materials perform optimally throughout their lifespan.
  • Weatherproofing: Proper installation methods create a watertight seal, protecting the roof deck and underlying structure from harsh weather elements. This prevents premature deterioration caused by moisture exposure.
  • Ventilation: Adequate ventilation allows for proper airflow within the roof system. This helps to prevent moisture buildup, which can lead to rot and mold growth, ultimately extending the lifespan of the roof.
  1. Maintaining Warranty Coverage: Most roofing materials come with warranties that cover manufacturer defects. However, these warranties are often voided if the roof is not installed according to the manufacturer’s specifications.  Here’s why using qualified contractors is crucial:
  • Manufacturer Training: Qualified roofers are often trained by the manufacturers of the roofing materials they install. This ensures they understand the proper installation techniques specific to each material.
  • Warranty Compliance: By using a qualified contractor, you have better assurance that the installation adheres to the manufacturer’s guidelines, keeping your warranty valid.
  • Documentation: Reputable contractors will provide documentation of the installation process, materials used, and manufacturer warranties. This documentation is essential for filing any warranty claims in the future.

In conclusion, proper roofing installation is an investment that pays off in the long run. It protects your home from costly leaks and damage, ensures a long roof lifespan, and safeguards your warranty coverage. By choosing a qualified and experienced roofing contractor, you can have peace of mind knowing your roof is installed correctly and will provide lasting protection for your home.

process of hiring a roofing contractor

Hiring a Roofing Contractor

Finding Qualified Professionals:

Research and Recommendations:

  • Online Resources: Utilize online resources like the Better Business Bureau (BBB), Angie’s List, or HomeAdvisor to check contractor ratings and reviews. Look for contractors with consistently positive reviews and minimal complaints.
  • Industry Associations: Search for roofing contractors who are members of industry associations like the National Roofing Contractors Association (NRCA) or your state’s roofing contractor association. These organizations often have certification programs and hold members to high standards.
  • Word-of-Mouth: Ask friends, family, and neighbors for recommendations of roofing contractors they have had positive experiences with. People you know can provide valuable insights into a contractor’s reliability, quality of work, and communication style.

Licensing and Insurance:

  • License Verification: Contact your local building department or licensing agency to verify that the contractor holds a valid roofing license in your area. This ensures they have met the necessary qualifications and passed relevant exams.
  • Insurance Coverage: Ensure the contractor has adequate insurance coverage, including:
  • General Liability Insurance: Protects you from financial responsibility in case of property damage or injuries caused by the contractor or their workers during the project.
  • Workers’ Compensation Insurance: Covers medical expenses and lost wages for workers who are injured on the job.

Getting Estimates and Contracts:

Detailed Estimates:

  • Scope of Work: The estimate should clearly outline the specific work to be done, including roof tear-off (if applicable), underlayment installation, chosen roofing material, flashing details, ventilation methods, and final cleanup.
  • Materials: The estimate should detail the specific brands and types of materials to be used, including shingle type, thickness, and warranty information. Don’t be afraid to ask about alternative materials and their cost implications.
  • Labor Costs: The estimate should break down the labor costs associated with the project, including hourly rates or a flat fee for the entire project.
  • Timeline: The estimate should provide a realistic timeline for the project’s completion, considering factors like weather and material availability.
  • Itemized Costs: Request an itemized breakdown of all costs to understand how much each step of the project contributes to the total price.

Written Contract:

  • Never rely solely on verbal agreements. A written contract protects both you and the contractor. The contract should clearly detail:
  • Project Scope: Ensure the written scope of work matches the agreed-upon details in the estimate.
  • Payment Schedule: Outline the payment schedule, including any down payment amount, staged payments tied to project milestones, and final payment upon completion.
  • Warranties: Specify the warranties offered on the materials and labor. This should include both the manufacturer’s warranty on the roofing materials and the contractor’s warranty on their workmanship.
  • Change Order Procedures: Outline the process for handling any changes to the project scope or materials after the contract is signed. This helps avoid disputes about additional costs later.
  • Dispute Resolution: Specify the process for resolving any disagreements that may arise during the project. This might involve mediation or arbitration.

By following these steps, you can increase your chances of finding a qualified and reputable roofing contractor to ensure a successful and stress-free roofing installation project.


In conclusion, a well-installed roof is crucial for protecting your home and ensuring its longevity. By understanding the roofing installation process, the various materials available, and the importance of hiring qualified professionals, you can make informed decisions. Remember to prioritize thorough research, verify contractor licenses and insurance, obtain detailed estimates, and secure a written contract. With careful planning and the right team, you can invest in a new roof that provides peace of mind and lasting value for your property.