Roof Replacement Cost Guide
No one ever said that being a homeowner was going to be cheap. However, keeping your home in good condition has obvious advantages. For one, it would definitely come in handy if you were to decide to sell. When it comes to Home Improvement, one of the top 5 major costs to the homeowner is roof replacement. In fact, on the average, roof replacement usually comes in third (cost wise) after kitchen remodeling and bathroom remodeling.
Reasons to Replace your Roof
There are a few reasons why you should consider replacing your roof. It is often unclear if you should replace your roof or just do some repairs. If this is the case, then you should consider consulting a professional roofing contractor in your area. Some of these professional contractors even offer free in-home consultation. However, you will need to check the terms and conditions of these consultants before deciding to use their free consultation services.
- Age: Especially in areas with extreme weather conditions, after 20 to 30 years, you may want to consider the option, as most roofs have a 25-year lifespan, especially if your roof is made from Asphalt or Wood.
- Buckling or missing shingles: Buckling shingles could be caused by prolonged direct sunlight, An old and worn roofing or even some sort of defective roofing. If you have missing shingles, Then you would most likely have leaks.
- Roof Valleys: These are the channels that run along the inside angles of the roof. The roof valleys are important as this is where rain and snow flow. These valleys can corrode, especially if leaves or other debris get trapped and this can lead to rain overflowing onto your roof.
- Leaks: If leaks are present, then something is definitely wrong with your roof! Leaks are a serious hazard to your home. Mold and mildew growth can occur due to leaking roofs. This poses a serious health issue to your family, especially to those who are sensitive to respiratory ailments. Another evident reason is structural damage to your house. A leaking roof can cause damaged rafters, wood deterioration and weakened wall framing.
Items to Consider
Before you decide to replace your roof, it goes without saying that you will have to consider the different types of roofs available. There are several types of roofing materials to take into consideration, with varying life spans and costs.
Please note that in roofing terminology a square is 100 square feet (i.e. an area of 10feet x 10feet). There are many Online Roofing Calculator which you can use to help you calculate the size of your roof (see below an example of roof size calculation). Once you calculate your roof size, you may want to consult a professional to reconfirm your calculations.
In summary, you need to consider the following points:
- Project Type: Do you need to replace the whole roof or can you choose to replace just some of the tiles? Would you need a professional to have a look and advise?
- Costs: How long will the roofing material last? Are there any warranties?
- Weight: How heavy is the material? Are there any special installation and maintenance procedures?
- Colors and styles
- Fire codes in your area: Some materials are not allowed in some areas as they are not fire-resistant
- Weather suitability: Does the material fit the weather in your area? Some materials are more suited for cold climate and some are more suited for hot climates
Types of Roofing Materials
The following gives a summary of the most popular Roofing Types, together with their Pros, Cons, House Styles that these roofing materials are suitable for, Life Spans and Costs (please note that the costs here are for the roofing material only).
The most common roofing material used in the United States (more than 75%). It can be reinforced with fiberglass or organic material (cellulose) without altering the appearance of the shingle.
- One of the least expensive materials available
- Easily available
- Easy to install
- Fits well with any architectural styles and a variety of colors.
- Bad environmental track record (made from petroleum products)
- The least green roofing material option
- Short lifespan
- Low insulative value
House Styles: Goes well with most architectural styles.
Life Span: From 15 to 30 years.
Cost: $50 to $150 per square.
Wood Shingles or Wood Shakes
Many homeowners love the look of wood shingles and wood shakes. Homeowners interviewed loved the way the wood material weathered to an attractive gray shade. Wood shingles are usually cut by machine, whereas wood shakes are hand-made. They are usually made from Cedar, Southern Pine or Redwood (available in other types of wood too).
- Rustic look
- Natural product
- Usually come in Class C fire rating and therefore fire codes in some areas prohibit the use of this material (however, homeowners can look for Class A fire-rating shingles that have been treated with fire-resistant coating)
- In wet climates, wood shingles tend to mold, split and rot
House Styles: Cottages, Bungalows, Tudor-style homes, Ranch homes, Historic-style homes and even some contemporary home styles.
Life Span: From 25 to 50 years.
Cost: $100 to $165 per square.
Clay and Concrete Tiles
These are very durable and come in various colors and styles (flat, ribbed or scalloped). However, these tiles are heavy and usually need additional roof framing.
- Long life span and durable
- Energy efficient (can reflect over 50% of the sun’s solar energy)
- Heavy and usually require professional installation
House Styles: Go very well with Mediterranean and Spanish-style homes, Mission, Southwestern, contemporary Ranch homes.
Life Span: From 40 to 50+ years.
Cost: $300 to $600 per square.
Comes in various colors, beautiful and has a distinctive and elegant look. Slate is also easy to repair. The quality of imported slate can vary. Dark colored slate is not recommended for high-temperature climates.
- Very durable and fire resistant
- Can be recycled
- Long life span
- Quarrying and splitting slate tiles has little environmental impact compared to the production of some other roofing products.
- Heavy and therefore may need extra framing
- Often require very professional installation.
House Styles: Colonial, French and European homes.
Life Span: From 50 to 100 years.
Cost: $500 to $1,000 per square.
Usually available in two types, i.e. panels and shingles. Usually made from copper, stainless steel, zinc or aluminum. They are also good for high-temperature climates, as they have high solar reflectance.
- Durable (i.e. lasts longer than asphalt and wood)
- High solar reflectance
- Often have a high percentage of recycled material and therefore environmentally friendly
- Lighter than most roofing material
- Resistant to extreme weather
- Can be expensive
- Noise from rain or hailstorms can be very irritating
- Slippery when wet, so it could be dangerous to plumbers or other workmen should they need to work on the metal roofs.
House Styles: Bungalows, contemporary, some ranch and cottage style homes.
Life Span: From 50 to 75 years.
Cost: $100 to $300 per square. $600 to $800 for some coated steels and copper.
Synthetic Roofing Products
Nowadays, more homeowners are using these materials, which include rubber, plastic and polymer roofing. Many of these products are made to give you the color, texture and look of wood and slate products. Homeowners are advised to check the warranty information before considering these products. This is because Synthetic Roofing products are relatively new and therefore their track record is not proven.
Furthermore, these products are manufactured with dyes. It is not fully known how these dyes will react to weathering and ultra-violet light exposure. Warranties therefore, may not cover these materials or there may be limited warranty only.
- Lightweight (compared to natural products)
- Not as fragile as natural products
- Relatively inexpensive
- Quality varies, may even absorb water
- Wear characteristics also vary
House Styles: Work well with various architectural styles.
Life Span: Warranties of up to 50 years.
Cost: From $300 per square.
These are composite tiles made from a mixture of concrete, clay and wood fiber. They are often made to look like shakes. Fiber Cement roofing come in a variety of colors and textures.
- Not as heavy as Concrete tiles
- Very durable
- Not good for very cold climates as they can crack
- Shorter life span than most roofing products
House Styles: Work well with various architectural styles.
Life Span: 20 to 30 years.
Cost: $500 per square.
Roof Replacement Process Flow
The following is a typical process flow for a roof replacement project. Please note that this is a very basic guide:
- Measurements (Pitch Ratio & Roof Size in Square Feet)
- Calculate Costs
- Obtain quotes from Roofing Contractors
- Sign Contract & Set Date for Project Start
Removal of Old Roof
- Property Protection (Use of protection tarps & plywood to protect your house & surroundings)
- Set-up toe boards & scaffolding for roof traffic
- Removal of old roofing, starting with roof ridges
- Clean-up debris
New Roof Installation
- Roof Inspection (inspect wood decking thoroughly)
- Replace any rotted wood decking
- Install water/ice shields in eaves, vents & roof valleys
- Install Roofing Felt (this is the underlying material of the new roofing to be installed)
- Draw chalk lines to keep the shingles straight
- Carry up shingles & begin installation of new roofing
- Final post-roofing inspection & debris clean-up
Flat Roofs vs. Pitched Roofs (sloped)
The common usage of "Flat Roof" is erroneous as all roofs should be sloped. It would be more accurate to say "less sloped roof". However, we will use "Flat Roof" for our discussion here.
The following are some of the differences between "Flat Roofs" and Pitched Roofs:
- Flat Roofs have a Pitch of less than 3:12
- The Pitch or Slope of the roof is usually stated as the Pitch Ratio (see below for an example of a Pitch Ratio calculation).
- All roofs really should be sloped so as to be able to drain any rain or ice or debris from the roof.
- Flat Roofs need a membrane system as a roof covering (you cannot use shingles on roofs with a Pitch Ratio of less than 3:12), so that there would not be leaking of stagnant water. The most common membrane systems are BUR (Asphalt Built Up Roofing is the most common type of BUR material), Single-Ply Membranes (made from either thermoset or thermoplastic material) and Modified Bitumen.
- Flat Roofs usually have large roof overhangs. Large overhangs do not block windows & thus have better lighting.
- Flat Roofs however, have the reputation of being problematic! The reason being that these roofs do not drain water well & are therefore prone to leaks. Therefore, it is important that the membrane systems are installed properly.
- Pitched Roofs are generally less expensive to install because shingle installation is easier to install than installing membrane systems.
- High Pitched Ratio Roofs (more than 5:12) are difficult to walk on when servicing and repairing.
Do it Yourself or Hire a Professional?
Finally, after you choose the type of roofing material and costs involved, you have to decide if you can replace the roof yourself or whether you need a professional to do the job for you. You obviously need to decide if you are competent enough to replace the roof. Also, do you have the time and patience to do the job well?
Most areas have a few roofing contractors and therefore you can “shop” around for a competent professional. You can always ask for a quote and look at completed work done by these contractors in your area (you may even want to consider asking the homeowners where these contractors did the work). You can also look online for feedback from other homeowners.
The contractor’s workers need to be licensed and insured too (otherwise, if a worker gets injured, the homeowner may be held responsible for medical and other costs incurred; Liability Insurance covers the homeowner should there be damage during the roof replacement).
The Costs of using a professional vary, depending on:
- Angle or pitch ratio (the number of inches the roof rises vertically for every 12 inches it extends horizontally) of your roof (the higher the pitch ratio, the higher the cost). For the example below, for 4 inches of height with the tape measure at the 12 inch mark on the horizontal level, your pitch ratio is 4:12. So the pitch ratio in this example is 1/3 (i.e. 4 divided by 12).
- Accessibility to the roof (the less accessible the roof to transport trucks, the higher the costs) and cost of material.
- The Roof Area (roof size is the largest cost factor). To calculate the roof area, you will need (1) paper & pen; (2) calculator (3) the pitch ratio of your house (4) square footage of your house (as detailed below).
1. Determine the roof pitch (in this example we are using 1/3).
2. Square your roof pitch (i.e. 1/3), which will yield 1/9 in this example.
3. Add 1 to 1/9 (i.e. 1 + 1/9) =10/9. Take the Square Root of 10/9 (you can use an online calculator, if you do not have one at home) = 1.05409.
4. Say you have a single story house of 1,500 square feet (if you don't know the square footage of your house, you can obtain it from your city's building department records). Multiply 1,500 by 1.05409 (i.e. 1,500 x 1.05409) = 1,581 square feet. So you will therefore need 1,581 square feet of roofing.
As you can see, the charges will therefore vary quite a bit. Roofers charge per roofing square (e.g. a 5,000 square foot roof is broken down into 50 squares).
Professional Roofing Contractor's Charges
Please note that the following is just an average roof replacement cost guide, as there are many variations. However, with this guide, you can calculate the average costs and therefore get a good idea of what it will cost to replace your roof. Once you have an idea of what it will cost, you should then engage at least 2 to 3 professional roofing contractors for their quotes.
If we use our previous example, and assume that your roof is 1,581 square feet, it means that it is about 16 squares (after dividing it by 100).
Typically, the roofing contractor would charge for: (1) Removing your old roof; (2) Installing the new roof; (3) Material costs of the new roof.
- Contractors charge between $100 to $150 per square (for a single shingle layer of roofing) to remove your old roof. Therefore for our example here, you would pay between $1,600 to $2,400 to remove your old roof
- For installation (for this example, we take Asphalt as it is the most common type of roofing), contractors charge between $100 to $400 per square. Therefore it will cost you between $1,600 to $6,400 for installation
- Asphalt Shingle Material costs between $50 to $150 per square. Therefore your material costs for this example would be between $800 to $2,400
- Your total average costs for this example would therefore be between a minimum of $4,000 (i.e. $1,600 + $1,600 + $800) to a maximum of $11,200 (i.e. $2,400 + $6,400 + $2,400)
On the average, Asphalt (installation costs $100 to $400 per square) is the most affordable roofing option, followed by Metal (installation costs $500 to $1,800 per square), Clay and Concrete Tiles (installation costs $600, to $4,000 per square) and Slate (installation costs $800 to $4,000 per square).
Miscellaneous Roof Additions Costs
A Solar Panel is a panel used to absorb the Sun's rays for electrical or heat generation.
The best time to install Solar Panels is after you have done your roof replacement. That way you will not have to pay extra money to disconnect your Solar Panels, do your roof replacement and then put them up again.
Another consideration is, do you have a suitable sunlit roof to justify the cost of installing a Solar Panel?
To protect roofs, manufacturers have come up with a possible answer, i.e. use a waterproofing sealant to the surface of the roof. However, it has to be installed by an experienced professional. A properly installed roof sealant can potentially protect your roof from weathering agents like the sun, rain & snow. It can also help to cool your roof, prevent mold & help with fire resistance.
It goes without saying that "Flat Roofs' need some sort of sealant, as briefly discussed above ("Flat Roofs" versus Pitched Roofs). However, sealants are less popular for pitched roofs, as homeowners do not feel they need to spend extra, as Pitched Roofs have better drainage.
A professional roof sealing job costs an average of $1,000. However, if the sealant will extend the life of your roof by a few years, the cost may well be worthwhile.
Flashing is a thin sheet or strip of water-resistant material that is installed at roof intersections and projections. They are mainly installed to direct water flow away from the house and from entering roof penetrations.
Roof Flashing is relatively inexpensive, so it pays to replace any roof flashing when replacing your roof. If you do not have existing Flashing, then you may want to consider installing them. The cost of installing Flashing ranges anywhere from $200 to $500.