Should I Convert My Flat Roof to a Pitched Roof?

Most people that are interested in converting their flat roof to a pitched roof are simply tired of dealing with leaks, repairs and other issues. Tar and gravel, and other asphalt based roofing, were the most popular roofing material for flat roofs until recently. Even today, there are roofing companies that recommend installing asphalt (aka Built Up Roof). These types of roofs dry and crack and lead to headaches even before the material warranty period ends. Additionally, any poorly installed flat roofing system requires constant upkeep and repair. As a consequence, many people look into converting their low sloped roof to a pitched roof, commonly called a Roof Conversion.

For those of you who are in this frustrating position, let’s take a look at all of your options, as well as the pros and cons of a conversion. Roofing manufacturers have introduced reliable flat roof membranes, such as TPO and EPDM, which have grown in both credibility and popularity over the last decade. While it may seem that shingles will solve all of your problems, the fact is that TPO and EPDM membranes can be just as water tight as a pitched roof.

It is important to find a roofing contractor that can identify the right kind of membrane and be able to install it properly. This is important, as the dependability of a roof is determined by the quality of material and the skill level with which it was installed. If you can find a qualified contractor to install a dependable membrane on your home or business, it can cost 3 to 4 times less than a roof conversion. White roofing membranes can also be extremely energy efficient, resulting in energy savings over time.

If you are considering converting your roof in order to raise the value of your home, keep in mind that the value of your home will only increase about half of the cost of the conversion. As a result, if you are considering selling your home within the next 7-10 years, converting your roof may not be worth the required time and money.

However, there are some viable reasons to convert to a pitched roof. Probably the best reason I have come across is a situation I ran into a few days ago. The owner was concerned that his flat roof’s support system was not structurally sound. He could hear the rafters creaking under the weight of recent snowfall. That creaking is usually the result of fasteners coming apart a little bit at a time. Nails and screws will creak as the structures wood members. If the fasteners back out, or if wood dries and shrinks, it could cause a dangerous and destructive situation.

A pitched roof conversion, done properly, will distribute weight to the bearing walls of the structure. In the previous case, a conversion would help his structurally unsound roof to become dependable long term.

Some other pros to converting your flat roof to pitched include:

You simply like the look of shingles. If money isn’t a concern, the perceived aesthetic value of a pitched system can be enough of a reason in and of itself.
A roof conversion results in easier and more efficient insulation. It is more economical to insulate a pitched roof at R40 than it is to try and insulate a flat roof with even an R19. (Insulating a flat cavity usually requires removing sheet rock or sheeting.) You can also insulate above the roof deck and below the waterproofing system with rigid insulation, but once again this is fairly expensive.
Vapor drive, which causes moisture to form on the underside of a roof system, won’t occur with a pitched roof as easily because you can create an efficient pattern of air flow. (If the humidity in the home is equal to the humidity outside, vapor drive will not be an issue.)
You may be able to create more storage space or even an added room in the cavity between the existing flat and newly pitched roof.
Pitched roofs have about a 40% longer life than flat roofs. They last 25-50 years, while a flat roof membrane will last about 15-20 years.
Flat roofs are about 10-20% more expensive to install than a pitched roof (after the conversion). This is because the membrane is more expensive to manufacture, as well as the need for more specialized labor.
In the end, it is really just up to you and your individual situation to decide whether a roof conversion is right for you and your home.

Roofing Terminology

Knowing common roofing terminology will enable you as a homeowner to make an informed decision about roofing materials that are good matches for your home’s style and the region in which you live. It will also help you understand the contract with your roofing professional and the project updates.
Some key roofing terms are listed below:

Asphalt: A waterproofing agent applied to roofing materials during manufacturing.

Asphalt plastic roofing cement: An asphalt-based sealant used to bond roofing materials. Also known as flashing cement, roof tar, bull or mastic.

Back surfacing: Granular material applied to the back side of shingles to keep them from sticking during delivery and storage.

Base flashing: That portion of the flashing attached to or resting on the deck to direct the flow of water onto the roof.

Built-up roof: Multiple layers of asphalt and ply sheets bonded together.

Butt edge: The bottom edge of the shingle tabs.

Caulk: To fill a joint to prevent leaks.

Closed valley: The valley flashing is covered by shingles.

Coating: A layer of viscous asphalt applied to the outer roof surface to protect the roof membrane.

Collar: Pre-formed flange placed over a vent pipe to seal the roof around the vent pipe opening. Also called a vent sleeve.

Concealed nail method: Application of roll roofing in which all nails are covered by a cemented, overlapping course.

Counter flashing: That portion of the flashing attached to a vertical surface above the plane of the roof to prevent water from migrating behind the base flashing.

Course: Row of shingles that can run horizontally, diagonally or vertically.

Cricket: A peaked water diverter installed at the back of a chimney to prevent accumulation of snow and ice and to deflect water.

Deck: The top surface of which a roof system is applied, surface installed over the supporting framing members.

Double coverage: Asphalt roofing whose lapped portion is at least two inches wider than the exposed portion, resulting in two layers of roofing material over the deck.

Downspout: A pipe for draining water from roof gutters to drain. Also called a leader.

Drip edge: L-shaped flashing used along the eaves and rakes to allow water run-off into the gutters and to drip clear of underlying construction.

Eave: The part of the roof that overhangs or extends outward and is not directly over the exterior walls or the buildings interior.

Exposed nail method: Application of roll roofing where nails are driven into the overlapping course of roofing. Nails are exposed to the elements.

Fascia: A wood trim board used to hide the cut ends of the roof’s rafters and sheathing.

Felt: Fibrous material used as an underlayment or sheathing paper, describes roll roofing materials.

Flashing: Pieces of metal or roll roofing used to form water seal around vent pipes, chimneys, adjoining walls, dormers and valleys.

Gable: The end of an exterior wall that comes to a triangular point at the ridge of a sloping roof.

Granules: Ceramic-coated and fired crushed rock that is applied as the top surface of asphalt roofing products.

Gutter: The trough that channels water from the eaves to the downspouts. Usually attached to the fascia.

Head lap: An overlapping of shingles or roofing felt at their upper edge.

Hip: The fold or vertical ridge formed by the intersection of two sloping roof planes. Runs from the ridge to the eaves.

Ice dam: Condition forming water back-up at the eave areas by the thawing and re-freezing of melted snow on the overhang. Can force water under shingles, causing leaks.

Interlocking shingles: Individual shingles that mechanically fasten to each other to provide wind resistance.

Laminated shingles: Strip shingles made of two separate pieces laminated together to create extra thickness. Also called three-dimensional and architectural shingles.

Lap: Surface where one shingle or roll overlaps with another during the application process.

Mansard roof: A design with a nearly vertical roof plane connected to a roof plane of less slope at its peak. Contains no gables.

Mineral stabilizers: Finely ground limestone, slate, traprock or other inert materials added to asphalt coatings for durability and increased resistance to fire and weathering.

Nesting: A method of reroofing, installing a second layer of new asphalt shingles, in which the top edge of the new shingle is butted against the bottom edge of the existing shingle tab.

Pitch: The degree of roof incline expressed as the ratio of the rise, in feet, to the span, in feet.

Low Slope – Roof pitches that are less than 30 degrees.

Normal Slope – Roof pitches that are between 30 and 45 degrees.

Steep Slope – Roof pitches that are more than 45 degrees.

Rafter: The supporting framing that makes up the roof structure; immediately beneath the deck; the roof sheathing is nailed to the rafters.

Rake: The inclined edge of a sloped roof over a wall from the eave to the ridge. They can be close or extended.

Ridge: The horizontal external angle formed by the intersection of two sloping sides of a roof at the highest point of the roof, hip or dormer.

Run: The horizontal distance between the eaves and a point directly under the ridge; or one half the span.

Selvage: That portion of roll roofing overlapped by the application of the roof covering to obtain double coverage.

Sheathing: Exterior grade boards used as a roof deck material.

Shed roof: A single roof plane with no hips, ridges, valleys or gables, not connected to any other roofs.

Slope: The degree of roof incline expressed as the ratio of the rise, in inches, to the run, in feet.

Smooth-surfaced roofing: Roll roofing that is covered with ground talc or mica instead of granules (coated).

Soffit: The finished underside of the eaves that extends from the fascia to the siding and hides the bottom of an overhang.

Soil stack: A vent pipe that penetrates the roof.

Span: The horizontal distance from eaves to eaves.

Specialty eaves flashing membrane: A self-adhering, waterproofing shingle underlayment designed to protect against water infiltration due to ice dams or wind driven rain.

Starter strip: Asphalt roofing applied at the eaves as the first course of shingles installed.

Tab: The weather exposed surface of strip shingles between the cutouts.

Telegraphing: Shingles installed over an uneven surface that show distortion.

Truss – A combination of beams, bars and ties, usually in triangular units to form a framework for support in wide span roof construction.

UL label: Label displayed on packaging to indicate the level of fire and/or wind resistance of asphalt roofing.

Underlayment: A layer of asphalt based rolled materials installed under main roofing material before shingles are installed to provide additional protection for the deck.

Valley: The internal angle formed by the intersection of two inclined roof surfaces to provide water runoff.

Vapor barrier/retarder: Any material that prevents the passage of water or water vapor through it.

Vent: Any device installed on the roof as an outlet for air to ventilate the underside of the roof deck.

How to Prevent Ice Dams and the Roof Leaks They Cause

Here we are in the midst of another cold Massachusetts winter and like every winter here in New England many property owners will have major issues with ice dams causing roof leaks and shingle damage.

Although it may seem as though ice dams are an unstoppable force of nature, they are actually quite preventable. Attics and cathedral or vaulted ceiling areas that have been correctly incorporated into the overall building envelope don’t have problems with ice dams and icicles in the cold seasons. Through the use of proper insulation and ventilation techniques ice dams can be stopped cold (pun intended).

Here a typical scenario for the formation of ice dams:

A house has a build up of snow on the roof.
The temperature outside is below freezing.
The temperature inside the attic is above freezing, thus raising the temperature of the roof itself to above freezing.
Because of the warm roof, the snow on top of it begins to melt from the bottom up.
This melted snow water tries to run down and off the roof.
As soon as the water reaches the edge of the roof it gets exposed to the freezing air.
The water refreezes as ice instead of snow in the gutters, if present, and along the edges of the roof.
As more and more melted snow water continues to run down the roof it just keeps freezing behind and on top of the previously frozen run off, forming a bigger and bigger ice dam.
So How Do Ice Dams Cause Roof Leaks?
The melted snow water doesn’t immediately freeze anymore after the ice dam has begun to take shape. Once the ice dam has built up a bit it literally creates a dam that traps the rest of the water trying to run off the roof behind it. While this trapped water will eventually freeze, it may take a while and during that time a portion of the shingles on this roof, behind the ice dam, are basically submerged in water.

Now of course your roof shingles are obviously suppose to protect your home from the weather i.e. rain and snow. However, most roofing materials are not meant to have a pond or river on top of them.

So What Can You Do To Prevent Ice Dams?

First and foremost you must recognize that proper insulation and ventilation is the key(see image on right). If we are talk about an attic area then typically this means that the insulation needs to run up the walls of your house then over the attic floor joists forming an ideal insulation envelope. In the attic scenario only the floor of the attic should be insulated, not the underside of the roof!

Proper ventilation is also required. Outside air needs to be able to enter the attic so that the attic temperature is the same as the temperature outside. You achieve this ventilation through the use of gable vents, soffit vents and a roof ridge vent.

In roof systems with attic areas below them it is fairly straight forward to have a contractor that knows what they are doing to correct any problems as far as proper insulation and ventilation. However, roof systems with a cathedral ceiling below them that have these issues are much more of a project to correct, but they can be corrected.

In order to have a properly ventilated and insulated cathedral ceiling the contractor must install baffles within each rafter bay before installing the insulation. These baffles allow air to flow between the soffit vents and the ridge vent which keeps the underside of the roof the same temperature as outside. If these baffles ore not installed in your cathedral ceiling then the contractor will need to remove the existing sheetrock and insulation from your ceiling in order to properly ventilate the area. This type of project will be more expensive than an attic project.

In addition to the ice dam issue, if your attic is warmer than the outside temperature you are also wasting lots of money heating that space. So basically you are paying extra money on your heating bill for the privilege of growing nice big ice dams and icicles that cause roof leaks and destroy your roof. Kind of makes it even worse when you think of it that way doesn’t it?

What Can You Do About Existing Ice Dams?

If it’s the middle of the winter and you have ice dams or through past experience you think they will be forming soon there are some measures you can take. First of all, if you don’t have experience climbing on a roof in the winter, especially with snow on it, don’t do it! Call a pro. What you can do is go to your local hardware store and buy a snow rake that has an extendable handle designed to pull snow off of the first few feet of the roof and attempt to pull some of that snow off, from the ground, before it has a chance to melt and refreeze along the roof edges. You can also do this once the ice dam has formed and keep it from getting any bigger and give it a chance to melt, hopefully.

Also, many roofing contractors, us included, work through the winter and often provide roof snow removal services in addition to their typical roofing services. This is a service we are happy to provide for our customers here in Massachusetts, for example. Again, please don’t try and do this yourself. Between icy ladders and slippery roof surfaces it is a recipe for disaster for the inexperienced.

There are also some products on the market that can assist in preventing ice dams before they form and melting them if they have already formed. You should be able to find a home improvement store in your area that sells a product that is basically a coated, heated wire that you fasten along the edges of the roof and then plug in when the conditions are right for the ice dams to form (see picture on right). These actually work pretty good, however, they aren’t solving the real problem which, of course, is ventilation and insulation issues. They may be right for some homes in some circumstances though.

Most home improvement and hardware stores also sell pellets or tablets that are designed to be thrown up onto the roof from the ground. These tablets then supposedly will melt the ice from the roof as they dissolve into the water that is running down the roof into the ice dam. I have no experience with these products so I can’t say for certain if they work as designed or not. However, some people say they have worked for their ice dam problems. A couple of things I would be worried about as a roofing contractor is potential damage to the shingles from the chemicals these tablets are made of (salt is no good for asphalt shingles), as well as possibly staining the roof with those same chemicals. And even in a base case situation this product is still just a band-aid for a greater problem.

Proper Roofing Techniques For Cold Climates

In addition to making sure that the roof has proper ventilation and attic insulation there is an additional level of security against ice dam issues and roof leaks that all responsible and ethical roofing contractors should be taking in cold weather climates with regards to pitched, asphalt shingled roofs. When a new roof is installed, these days, an extra layer of protection called ice and water membrane should be installed from the edge to at least 3 feet up the roof.

What to Expect During Your Home’s Roof Replacement Project

Replacing your roof is an essential part of maintaining your home. A damaged or improperly maintained roof can cause thousands and dollars in damage to other parts of the home. Repairs only go so far, and eventually it will be time to replace your roof entirely. Replacing your roof can seem like a daunting task for the first time homeowner. Choosing between hundreds of professional roofing contractors can be confusing. Thankfully, the project of getting a new roof is not too complicated, and it helps to know what to expect.

The first step in any roof replacement project is obtaining estimates and choosing a contractor. It’s a good idea to research several companies. Make sure they have good reputations and are licensed in your state. Be sure to obtain estimates from several contractors before signing a contract, as roofing estimates can have a wide range. There are many factors that can influence the cost of a roof replacement. It’s good to know a little about them before you get too involved.

The size and slope of the roof, the materials being used, and the region of the country can all affect the final cost of the project. A roof that is particularly steep and slippery will cost more to replace than a roof that is more easily accessible. The height of the roof matters as well. Roofs on two-story homes are more expensive to replace than roofs on ramblers or ranchers. This is simply because it’s easier for the workers to access a roof that is closer to the ground. Also, like almost anything, prices vary depending on where you live. Roof replacements cost more in places where the general cost of living is higher. The frequency of roof replacements differs depending on the region of the county as well. Roofs in the Midwest generally need to be replaced more often than roofs in other parts of the country due to extreme weather. Likewise, homeowners in Southern California replace their roofs less often since the weather is usually mild year-round.

There are several different types of roofs you can have installed. The materials can range in price anywhere from $1 to $40 or more per square foot. The most common roofing material is asphalt shingles. These are relatively inexpensive and are usually guaranteed to last anywhere between 20 and 30 years. They come in may different colors to compliment the exterior of your home. Another form of roofing is wood shake, which usually costs $6 to $9 a square foot. These roofs are usually made of cedar and can last 12 to 25 years, but they require almost constant maintenance. Metal roofing such as copper or aluminum can cost $15-$20 a square foot. Tile roofs, such as terra cotta, are generally used in southwestern architecture and cost $6 to $9 a square foot. (Tiles are not recommended in areas with frequent rainfall, as they have a tendency to leak.) A slate roof is the most durable, though it is also the most expensive, and can cost up to $40 a square foot ($120,000 to replace a 3,000 square foot roof). Slate is generally used on upscale homes and can last up to 200 years or more depending on the quality.

Along with being inexpensive, asphalt shingles require little maintenance, making them the most popular roofing choice for American homeowners. While asphalt shingle roofs are often designed to last 25 or 30 years, the actual life span of your roof can vary depending on where you live. High speed winds, hurricanes, heavy storms, blizzards, and dramatic temperature fluctuations decrease the longevity of your roof. Estimates for replacing an asphalt shingled roof can range from $1,500 to $9,000 depending on the size of the roof as well as location.

The cost of a roof replacement project varies depending on where you live. A roof replacement costs less in the Midwest than it does in the Northeast. In places where the general cost of living is higher, roof replacements will cost more as well. If you live in the Midwest, you will need to replace your roof more often. High speed winds, tornadoes, blizzards, and ice storms will all wreck havoc on your roof. Temperature fluctuations can also damage roofs. In the desert the temperature can be over 100 degrees during the day and drop to 50 or 40 degrees at night. 20-year asphalt shingles in Arizona and New Mexico last on average only 15 years, due to sustained damage from temperature fluctuations. Homeowners in regions with mild weather can get away with more moderate roof repairs, putting off full replacements for longer periods of time.

Roof replacement estimates may vary depending on all of these factors (location, materials, etc.). The final cost once the work is completed may be higher than the initial estimate, as your roof may have some unforeseen damage that will add to the final cost . Underneath the shingles, your roof could be rotted or have water damage. Replacing the roof support system can add thousands of dollars to the bill, depending on the extent of the damage. This is a good incentive to keep your roof properly maintained and have it replaced on time.

When you’re choosing your roofing contractor, ask for references. You’ll definitely want to see examples of their work on local homes. When giving an estimate, a contractor will come to your house to inspect your roof. He’ll come up with a number that factors in the cost of materials and labor, including the cost of stripping and throwing away the old shingles. The estimate should include the cost of removal and disposal of the old roofing material. If not, ask about this to avoid surprises. There is a chance that there will be some unforeseen costs in the project, so it is good to avoid as many of these as possible. After the visit, they will send you a written contract. A contract from a roofing company should include a description of what is to be done, as well as when it is to be done and a schedule for payment. Having it all in writing can protect the homeowner later on. Be sure to shop around before settling on a specific contractor, as prices can vary considerably.

Once you’ve chosen your roofing materials and your contractor, it’s time to set a date for the project. The actual work of replacing the roof can take anywhere from a few days to a few weeks, depending on the size of the roof. You should plan to have someone at home while the work is being done. If they have any questions or discover any additional problems with your roof, it helps that you are home to discuss things with them.

Before the workers arrive, it’s good to remove any items that may get in the way of their ladders. Climbing on roofs can be dangerous, even for professionals, so it’s best to stay out of their way. First, the roofers rip out all the old roofing shingles and replace any rotted or damaged wood in the roof. Next they lay a base, and then they lay the shingles. Roof work is noisy. Expect to hear a lot of hammering as well as people running around all over your roof. It’s not really an invasive home repair. You won’t have workmen coming inside your house. As long as you don’t mind the noise, it’s not much of a hassle.

When the old shingles have been stripped, any un-shingled portions of the roof should be covered with a tarp overnight to protect your home in case of rain or overnight storms.

Once your new roof is completed, make sure the workers have cleaned up all the debris that has fallen. When a roof is replaced, the workers usually toss the pieces of the old roof onto the ground or into a dump truck as they’re working. Once the bulk of the old material is disposed of, responsible companies will clean up after themselves to ensure customer satisfaction. They usually have a magnetic broom that picks up all the nails and other materials that can be hazardous as well as unsightly. You may find a shingle or two in your yard afterwards, which is perfectly normal.

When you have roof work done, you should never pay anything up front. You always pay after the job is completed. This is standard procedure. All reputable roofing companies operate this way.

Environmentally Friendly Roofing

The roof is one of the most important features of your home so it’s very important that you choose the right roofing material so that your roof will last you many years. Asphalt shingles are the most commonly used roofing material. Asphalt shingles are very harmful to the environment because they absorb heat, hold on to that heat for a long time, and are rarely recycled (because it is difficult). Asphalt shingles are the most popular roofing material because they are cheaper.

If your roof is getting old and needs to be replaced why not replace it with an environmentally friendly roof. There are numerous choices available in green roofing. Here are a few:

The Living Roof This is one of the most popular choices when it comes to green roofing. These roofs contain a layer of soil and plants grow on top of them. A living roof provides much better insulation than an asphalt shingle roof. A living roof helps it blend into its surroundings, and they’re beautiful. The topsoil that was removed during construction can be used as part of the living roof. Green roofs contain plants which help to replace the plants that were destroyed when the home was constructed. Most living roofs are found in Germany. Green roof systems can either be intensive or extensive depending on the plant material and planned usage for the roof area. Intensive green roofs use a wide variety of plants that may include trees and shrubs. They are extremely heavy and require a lot of support. Extensive roofs usually contain herbs, grasses, and mosses. They are not as heavy as intensive roofs. Green roofs can lower your electric bill. They also keep rain water from running off into the ground. The plants on the living roof can help remove pollutants from the air.

Metal Roofs Metal roofing is sustainable. It contains a significant amount of recycled material. It lasts a lot longer than asphalt shingle roofs and hardly ever needs to be replaced. When metal roofing needs to be replaced, it can be recycled. Metal roofing is fire resistant and can withstand strong winds. Metal roofs will not rust, crack, or rot. It never needs cleaning. Metal roofs are light weight so they don’t require a lot of support. Metal roofs can also be put over the original roof which saves removal and disposal costs.

Cedar Shake Roofs Cedar shake roofs are also very popular. They are made of untreated cedar and they don’t rot like other wood material does. They also last longer than asphalt shingles. Enviroshake┬« is a composite roofing product that replicates the look of an antique cedar shake roof but is more durable and more resistant to wind, water, mold and mildew. Enviroshake roofing is mostly made from recycled materials. There are several environmentally friendly options available for cedar shake roofs. One is real cedar shingles which are harvested from well-managed forests or shake tiles made from recycled materials. Either way, you’ll get a long-lasting, beautiful roof that will add a traditional look to your home.

Ceramic Tiles Ceramic tile is mainly used in the Southwest. Ceramic tile roofs are also nontoxic and long lasting. Individual tiles may occasionally need to be replaced but the whole roof is usually durable. Unglazed tiles are the most popular, but glazed ones also exist. Tiles tend to be expensive, and are also very heavy.

Solar Tiles Solar roof tiles look just like normal roof tiles however they are covered with a thin film photovoltaic (PV) material which generates electricity. One tile by itself doesn’t produce much power however covering an entire roof can produce a lot of electricity. In fact, an entire roof covered with solar tiles can easily generate enough power for your entire home.

If you choose to install solar roof tiles, you still will need to stay on the electric grid since even the sunniest climates have cloudy days, which limits how much power the tiles can generate. You should still be able to save a substantial amount on your electric bill.

This is an excellent time to purchase solar powered tiles. There are many excellent state and federal tax incentives (up to 80% of the cost). You can increase the value of your home and save on your electric bills by installing solar tiles.

The solar roof tile is made up of photovoltaic modules that are capable of being integrated into any standard roofing system. Solar roof tiles are connected by electrical sockets on their underside. This creates a single electrical unit, and therefore, an electric current. Basically, solar roof tiles use the sun’s rays to absorb heat and generate electricity for your home or building.