When it comes to replacing your flat roof, you need to think long-term. Getting a cheaper roof, such as EPDM Rubber, may be appealing at first, but you need to consider some factors that will affect the total price of your new roof. Here we will discuss in detail what the total roof replacement price includes, and factors affecting it.

Installation price from every roofing company also includes that company’s overhead or cost of running the business. For example, an established roofing company should be fully insured. This includes adequate Liability and Worker’s Comp Insurance. If for example you get a very low bid, consider that the bidder might not be adequately insured or have no insurance at all. If that is the case and you hire such a contractor, you will be responsible for any damages or injury claims that may occur.

Introducing IB PVC Roof – the longest lasting flat roofing system.

Over the last 30 years, IB Roofs, once a small family-owned company importer and installer of German-developed PVC flat roofing systems, has become a household name in the flat roofing industry. There is a reason for IB’s success – it is the ultimate quality of their products and unparalleled customer service. IB’s original roofs from 30 years ago are still in service and performing well, and when it comes to working with customers, IB will go out of their way yo give you the product you are looking for – be it a color of the membrane, a thickness, or special application requirements.

Quality of IB Flat Roofs:

IB Roofs has not changed the formulation of their PVC membrane since its early days in the late 1970′. Today’s IB membrane is the same great proven product that they were importing from Germany 30+ years ago. IB did not try to make the product cheaper by using less expensive components and fillers. On the contrary, IB has chosen to use the more expensive non-wicking scrim to prevent the membrane from splitting in the center due to water penetration, as is often the case with cheaper TPO roofs.

At some point, there comes a time when flat roof patches stop working and it is time for a replacement.

Here we will review flat roofing cost structure and factors affecting your price, IB Roof prices in Massachusetts and surrounding states ( CT, RI, NH, ME and VT). We’ll also reveal insights into choosing your flat roofing contractor, and what you should expect to pay for your particular roof, as well as your specific roofing product choice.

Flat Roof Replacement Cost: Residential and Commercial

Our general pricing for flat roof replacement works in the following manner:

Residential flat roofs are priced at $675 per square for a simple roof, with no existing roof removal. This includes 50-mil IB Roof membrane, 1/2 inch foam insulation with 2 r-value, perimeter pressure-treated wood nailer and half-roll membrane around the roof edges for wind-uplift prevention. Roof attachment using heavy-duty screws and barbed plates, 6 inches O.C. along the perimeter and 12 inches O.C. in-field. All required roofing parts and accessories are included.

Generally, for a 1000 sq. ft. residential home, your cost should be around $6750 for an average (simple) roof. If you would like to upgrade the membrane type or add more insulation, this will slightly increase your price. Please note: For all residential installations, all IB roofing membranes come with a lifetime residential warranty, therefore there is no need to upgrade from 50 to 80-mil product, as both will perform the same in protecting your roof from the elements and will remain water-tight throughout its life and beyond.

Commercial flat roofs are priced at $600 per square for roofs over 25 squares (2500 sq. ft.) The price difference from residential roofs is due to ‘economy-of-scale’ factors and lower per-square ‘setup’ and insurance costs.

If your commercial roof is around 50 squares you can expect a $30000 price range.

Use our interactive roof price calculator to estimate the cost of you roofing project. You can choose different roof options difficulty level, and will get ‘quotes’ for an IB roof, as well as other roofing products and approximate energy-savings derived from using an IB roof.

Please Note: All prices described above are assuming an ‘average’ roofing project and may/will change depending on your roof’s condition and scope of work required. The price may change in either direction, and will be determined on a case-by-case basis.

We are a premium roofing contractor and do not compete with other roofing companies solely on price. Our roof packages are priced accordingly to the quality, warranty and customer service we provide.

IB Roof packages and prices in New England

All packages described below include roof installation in accordance with manufacturer’s specifications and state/local building codes. They also include the cost of building permits, material warranty and our labor warranty. Prices below do not include tear-off of the existing roof, as that usually varies a lot from one flat roof to another. The cost of a tear-off is determined on a case-by-case basis when we perform a roof inspection. Please refer to our Residential roofing and/or Commercial roofing sections to see the available material / color / membrane thickness options available for your particular roof.

Package 1 – 50-mil white residential IB Roof with Lifetime warranty:

Our basic and most common roof package, includes 50-mil white IB Roofing membrane with all necessary trim, flashings and accessories such as drip edge, air-vents, inside/outside corner flashings, drains, etc., and 1/2 inch fan-fold Styrofoam insulation.

Cost of this package starts at around $675 per square (100 sq. ft.) of roof area.

Package 2 – IB Traditions flat Roof – Architectural Shingles Pattern imprinted onto the membrane:

IB Traditions was created specifically for low-slope roofs with aesthetics in mind. They offer the beautiful look of architectural shingle combined with proven reliability of an IB roofing membrane to give you decades of leak-free performance and curb-appeal. IB Traditions come in three color options: Sierra Vista ( beige / brown ), Stony Ridge (grey) and Mountain Spruce (green). To maintain a consistent shingles look, all IB Traditions installation feature hand-welding of all seams, and use special accessories / flashings designed to match the aesthetics of IB Traditions.

Cost per square for IB Traditions is $775-825, and includes 1/2 insulation and all necessary trim and flashings.

Package 3 – 80-mil white residential IB Roof with a Lifetime warranty:

Includes 80-mil white membrane, 1/2 insulation and all necessary trim / accessories / flashings. Cost per 1 square is $800. If you are looking for an 80-mil Color IB roof, there are six standard colors available and $850 per square. For custom colors the minimum order must be 100 squares ( This is the requirement of IB Roof Systems, and we have no control over it).

One: Roof Installation Prices

Our pricing structure is based on two direct (main) variables and a number of indirect variables that affect the total price of your roof replacement project. You can expect similar pricing methods from other roofing contractors.

First cost variable: Roof Size

The most important variable is the size of your roof. The bigger the roof, the higher the roofing cost. We base our pricing on the number of Squares, where each square is equal to 100 sq. ft. For example, if your flat roof is 1900 sq. ft. it is 19 squares.

Second cost variable: Roof difficulty

The difficulty of roof installation is the second most important variable affecting the cost of your roofing project. If you have a simple roof with a minimal number of roof penetrations (such as HVAC units, sky-lights, roof drains, through-wall scuppers, vent-pipes, posts, etc.), then your roof prices will be much less than if you had a more difficult roof with multiple roof penetrations and obstacles that require more roof flashing details. These roof penetrations require a great deal of professional manual labor and time, and slow-down the entire roof installation process.

Another factor associated with roof difficulty is the roof’s present condition, and presence of gravel and/or multiple roofing layers. These layers generally require removal and consume a lot of time because it is necessary to dispose of them. At the same time, roof removal must be performed quickly to eliminate the possibility of water penetration during the removal process.

Third cost variable: Indirect costs and material upgrades

Additionally, you can expect changes in roofing cost, depending on ease of access, roof location, and material options: As far as material options go, we offer a complete line-up of IB roofing membranes for residential and commercial installations. This includes: 50, 60 and 80-mil membranes in white and custom colors, as well as specialty membranes such as ChemGuard for restaurants, and IB Traditions (Architectural shingles pattern imprinted onto the membrane) and a Slip-proof IB DeckShield for walk-on flat-roof decks. We also offer a wide range of insulation options from 2-r fan-fold foam insulation to 20-r 3.3 inch ISO board and “tapered insulation” to create a slight roof pitch for drainage purposes.

Total Cost Concept

Consider the total installation price of the new flat roof. It will include: labor, materials, warranty and other factors. Roofing materials usually carry a manufacturer’s warranty period ranging from 5 to 25 years for commercial installation. Residential warranties will range from 5-15 years, while IB has the only Residential Lifetime Warranty in the industry. However, residential warranties are more complex, as many flat roofing manufactures will not warranty residential installations, or they fill impose certain requirements before they issue that warranty.

Any roofing job should also include a Labor warranty from the roofing contractor, and usually you can also purchase additional labor warranty from the manufacturer. IB Roofs offers an ‘NDL’ or No-Dollar-Limit labor warranty, which you can purchase as an additional ‘insurance policy’ for your roof.

Flat Roofing – thinking long-term

Most roofing contractors will warranty the water-tightness of the roof they install for the minimum period required by state law or building code. In Massachusetts for example, such minimum period is 2 years. After that, you are usually on your own. We find this especially troubling when someone chooses to install an EPDM or a black-rubber roof, which is especially popular among roofing contractors for its low materials cost. However, rubber roofs usually start to leak within 5 to 8 years after they are installed, due to failing seam adhesives. By this time your labor warranty has already expired and the cost of repair is on you – the owner.

We at CoolFlatRoof warranty our jobs for the length of the material warranty! We can do so, because we exclusively use IB PVC/CPA roofs, and we know that our roofs will NOT leak due to failing seams or other flashing detail.

Two: Overheads or Cost of doing business

Insurance Costs

It is in your best interest to hire a fully insured roofing company. However, adequate insurance coverage for a roofing company is very high: Worker’s Comp is usually 40 cents for each 1 dollar of payroll, or higher if the company had some incidents in the past. Liability Insurance is cheaper, but still it is one of the most expensive in the construction industry, due to possible damages if a contractor fails do adequately protect the building from water during or after installation.

Advertising: Market acquisition cost

Another considerable overhead for most roofing companies are the Marketing/Advertisement costs, as well as Sales-force commissions and office expenses. For many roofing companies, ‘market acquisition cost’ often range from $500 – $1500 per job. These include ‘Yellow Pages’ and news-paper ads, direct mailing, and Internet advertisement, such as Google or Yahoo Pay-Per-Click ads. As a result, you the customer, end up paying these expenses, or as we call it ‘marketing taxes’, that are not directly related to the cost of you roofing job.

We at CoolFlatRoof, do not spend any money on advertisement, except minimal expenses to run our web-site (around $100/year), so we will not charge you the ‘marketing tax’. Instead, we will provide you with the best materials, workmanship and warranty, for less.

Three: Ongoing repair and maintenance expenses

Ponding / Standing Water

While maintenance for most flat roofs is mostly due to the location of the building and surrounding conditions, one of the most frequent maintenance/repair expenses is due to ponding water. Positive drainage is preferable for any flat roof. However, the very nature of flat roof construction makes it often impossible to avoid ponding water accumulation, or it is too expensive to fix it. Ponding water can be eliminated in two ways: Installing Tapered Insulation, or creating a pitch, which is often impossible due to building design. Both are extremely expensive and will cost more than the roof itself, so eliminating ponding water is often out of budget.

While most flat roofing manufactures will void their warranty if there is presence of ponding water for periods of more than 72 hours after the rain, IB Roofs are explicitly warranted against ponding water and it is proven that an IB roof will keep your home or building dry even if you have big puddles of standing water for long periods of time!

Roof Repairs

As we mentioned above, many flat roofing systems will start to leak with-in 5 to 8 years after installation. Most roof leaks occur as a result of ponding water, failing seams, and to a lesser degree, faulty installation. Other factors affecting performance of a flat roof are weather conditions and devastating UV rays of the Sun. This is very true in the New England. We have hot summers and cold winters, and the temperature can dramatically change in matter of hours. Refer to our flat roof repair guide for more information on how roof leaks occur, and what your repair options and costs will be.

In most cases these repairs will be an out of pocket expense for you, as the usual warranty period will be long over by that time. We on the other hand will uphold our warranty after the usual 2-year period, if the leak happens. However, we do everything right the first time so there is usually no need to repair our roofs!

Four: Energy costs/savings

Cool, energy-efficient roofing form IB

Unlike most conventional roofing systems such as Epdm black-rubber, or Asphalt/Tar based BUR roofs, which attract, store and transfer solar heat, white IB Roofs reflect as much as 90% of the solar heat, and carry a Cool Roof certification! Even if you choose one of IB’s color choices, they are also certified by the Cool Roof Council, by implementing highly reflective color pigments. This will save you tremendous amounts of money in reduced HVAC costs. IB roofs act as a complete thermal barrier and increase the R-value of your roof, thus also reducing your heating expenses in the winter. By adding more insulation you will further increase the thermal qualities of your roof.

Conclusion

An IB Roof is the best choice when it comes to flat roofs. An IB Roof has the lowest Total Cost combined with unsurpassed quality and longevity. If the need to repair your IB roof ever arises, such repairs can be performed even 20 years from the day of installation, with IB’s unique Hot-Air fusion welding. It is however highly unlikely, unless there is unforeseen physical damage to the membrane. Expect not to have to repair your IB roof, ever!
An IB Roof will eliminate your ponding water problems and you will avoid expensive pitch-change. IB will also save you money every year by reducing your energy cost, and you will be covered by the Industry’s Best warranty!

If you are looking for a sustainable, long-lasting roofing product for your home or business pitched roof, the Metal Roof will be the perfect choice for you. Known for decades of leaks and corrosion free service, Aluminum metal roofs are becoming the prime choice for quality and longevity oriented home and business owners looking for a new roof. With its Cool Roof properties and permanent design, metal roofs will outlast any conventional asphalt shingles roof. Metal roofs are light-weight, and do not require any structural modifications. In fact they are only 1/4 the weight of regular shingles and 1/10 the weight of slate, and ceramic / concrete tile.

Use our Flat Roof Calculator to estimate the installation cost of a new IB Roof, as well as compare it with other alternatives. You can also estimate your annual energy savings derived from installation of an IB roof.

Are you excited about an IB Roof? Fill out our Roofing Estimate Request form and indicate which IB product you are most interested in, as well as details about your roof. We will contact you very soon after receiving your request, and we will work with you to provide the best roofing system available!

This is part 2 of our rubber roofing guide. In this part we will explain shortcomings of rubber roof (such as inherently faulty design), inability to hold ponding water and generally short life span, etc.

We will aslo demonstrate how many roofers are “trained” in installation of EPDM single ply roofing systems, results of their work (our Horrible Rubber Roofs series), and explain why we recommend that you avoid installing a rubber roof on your house.

Read this and you will save yourself lots of cash and many headaches. Also see our special “Horrible Rubber Roofs” video series below!

The truth about residential flat roofing market and contractors.

This rubber roof is just 1 year old, and has been leaking since day one, until we replaced it with a lifetime IB PVC flat roofing membrane.

Rubber Roof Contractors: It is unfortunate, but most residential flat roofs are installed by roofing contractors that specialize in asphalt shingles. Since they can easily purchase rubber roofing materials from their roofing supply warehouse, and are not required to be certified installers, nor do they need any special training or equipment, they will often undertake such projects to keep their crews busy.

Incorrectly installed EPDM roof in Quincy, MA – rubber glued right over shingles:

Horrible Rubber Roofs videos:

Horrible rubber roof part 1.
Location: Brockton, MA
Date taken: SUMMER 2011

Horrible rubber roof part 2.
Location: Revere, MA
Date taken: Fall 2011

Horrible rubber roof part 3.
Location: Country Club in Central MA
Date taken: Summer / Fall 2011

These are just some roof inspections that we did in the summer / fall of 2011. Look – even commercial roofs are not immune to hack roofers and faulty materials (like rubber roofing), but in residential, this is much more common.

Getting a quality flat roof installed:

The truth is that to get a quality rubber roof installed, it usually has to be done by a commercial roofing company that specializes in flat roofing. However, it is often the policy of such companies not to work with residential customers, for which there are many reasons. These contractors work with large commercial and institutional customers, employ union workers who are trained roof mechanics, specializing in their particular niche. For example, a commercial roofing contractor will have separate crews doing metal roofing or slate – these guys are “roofers”, and yet another crew doing flat roofing ONLY – these are “roof mechanics”.

A residential roofing contractor usually employs just roofers, who are good at what they do all day long – install asphalt shingle roofs, and often do not have a clue about how flat roofs work. When they get a potential client with a flat roof, they go to their supplier, ask what supplier has for flat roof, and the salesman at the supply warehouse TEACHES the roofer how to install EPDM rubber. This is not creative fiction or a product of my imagination – I see this happening nearly every time, when I come in to the supply store to get something.

“Trained rubber roofing installers”: If you are lucky, you may get a roofer that has received some sort of training about rubber roof installation. For example, one of my suppliers, provides installation training programs for their roofing contractors who install only asphalt shingles. The idea behind such training seminars is to increase awareness and solicit sales of more roofing products. A manufacturer technician provides a sample installation on a 8×8 feet demo stand.

Bellow is and example of such “hands-on rubber roofing training”.

As you can see, the roofers just sit around the demo stand while the MFG Installation technician shows them what to do. The whole demonstration took about an hour and a half, and covered thing like installing flat roofing insulation (ISO), adhering rubber to the ISO board, flashing a sky-light / chimney penetration with un-cured flashing material, installing the membrane up the vertical wall, cleaning & priming seams and installing seam tape, installing drip edge and a tape to seal the drip edge fasteners, and installing termination bar. In the same 1.5 hours we’ve also “learned” how to correctly apply yellow glue – membrane adhesive, seam primer – seam & flashing glue and how to install these systems in the winter, while violating manufacturer’s installation specs.

Out of 25 or so roofing contractors present, there were about 15 or so questions particular to the installation details. 7 of them where asked by me! Bear in mind that I already knew how to install a rubber roof and attended the event to talk to my salesman, representatives of the metal roofing manufacturer and for free refreshments

In any case, each one of those 25 or so roofing contractors, willing to learn a new, and very complicated roofing system, asked an average of 0.3 questions about this system.

Rubber roofs for residential customers: It was clear that my supplier and the roofing representatives were selling to Residential Roofing Contractors. Not once did they mention roof-top HVAC units, roof hatches, elevator shafts, gas/electrical pipes, roof drains, etc. They did however insist that the rubber is a good choice for a low slope shed dormer (without mentioning the poor low slope roof ventilation and ice dam prevention associated with shed dormers). They also mentioned that rubber is a good choice for a flat roof decks and patios.

Here you will find video profiles of roofs we installed in Massachusetts, Connecticut and Rhode Island. These videos will demonstrate how the roof was installed from beginning to end, as well showcase short excerpts taken during roof installation, such as installing standing seam metal roofing panels, or hot-air welding of seams on IB PVC roof installations. Most videos are available in High Definition (HD 720P) to better show the details of the work performed.

You can also check out our roofing job profiles gallery which shows some of the roofs we installed in MA, CT and RI. Roof video profiles here will be presented in no particular order. If we’ve already written a full job profile, we’ll reference it below the video.

You can see more of our roofing videos on our YouTube Roof Video channel.

New Roof installation videos, added in March 2011

IB Flat Roof installаtion with Tapered ISO insulation- Cambridge, MA

IB PVC flat roof installation with 1/8″ tapered ISO insulation in Wayland, MA

IB PVC Flat Roof installation wit 3″ ISO insulation in Weston, MA

Flat roof installation and slate roof repair in Brookline MA

This PVC flat roof was installed in Brookline, MA on a roof of a home undergoing major renovations. The old rubber roof (with 5 layers of tar roofing underneath the rubber) was leaking, and the slate roof adjoining the flat roof was also in poor shape.

We removed old roofing, wet insulation and old slate roof, and installed new plywood over entire roof deck, 20-r value 3.3″ ISO insulation on a flat roof (sloped roof had insulation between the rafters) and new 80 mil IB PVC roof on flat and sloped sections of the roof, 4 inch Dark Bronze drip edge around roof perimeter, and copper drip edge with PVC coated flange on the sloped edges of the roof. The video is in two parts – on showing preparation work and slate roof repair, and the second one showing roof installation.

Part one – roof preparation – tear off, plywood installation and slate roof repair:

Part two – installing insulation and IB PVC Roof:

Standing seam metal roof in Plymouth, MA

This aluminum standing seam metal roof was installed in Plymouth MA in the spring of 2008. The job was about 2500 sq. ft. total. The roofing material was .032″ aluminum metal roof in Patina Green color. Check out full roofing job profile – Metal Roofing in Plymouth MA.

Rubber roof repair in Boston, MA

This rubber roof repair was performed on a residential rubber roof in Boston MA in October 2010. We prepared and patched three leaking outside corner flashings – two at HVAC units, and one at a parapet wall. If your rubber roof roof leaks, we offer rubber roof repair service in metro Boston MA, which includes 2 hours of repair work, all needed EPDM flashing materials and accessories, and costs only $375.

80-mil IB PVC flat roof with copper drip-edge in Newton, MA

This new IB roof was installed in Newton, MA in summer 2010. The job features include IB’s new copper drip edge with PVC flange – now you have a choice of not only PVC clad galvanized steel drip edge in white and dark bronze colors, but also stainless steel and real copper drip edge, and the roof system integrity will remain the same as IB material can be welded to the flange of copper drip edge. Check out the IB flat roof installation steps, to see how an IB roof is installed.

This flat roof in Newton MA also had a walk-out roof deck / balcony on the side, for which we used 80-mil IB membrane with floating deck on top. Check out the complete roof job review of this flat roof in Newton MA.

Metal Shingles Roof in Johnston, RI

This Tamko Metal Works steel shingles roof was installed in the summer of 2007. Back then, the GAF DeckArmor underlayment, which we use on all out metal roof installation was in it’s first edition – you can see that it is grey, whereas now it is light blue color, and a little thicker and stronger.

This metal roof installation included tear off of 2 layers of asphalt shingles, installing the GAF DeckArmor underlayment and Tamko steel metal shingles roof – Stone Crest Slate profile in Vermont Blue color. There are four roof sections and about 75 feet of roof to wall flashing, where we had to remove old ceder shingles siding off the walls, so we could install underlayment and side-wall flashing at least 6 inches up the wall. Total roof size was about 2100 sq. ft.

PVC Roof Repair

Besides rubber roof repair, we also provide PVC roof repair services (as well as TPO roof repair) in the metro Boston area, and within 50-mile travel distance from Boston. Here are two examples of PVC roof repair that we did. In all PVC roof repairs, we use new IB PVC roofing material, and MEK cleaning solution or acetone to clean and prepare an old roof for welding a new membrane. Check out our PVC Roof Repair page.

Trocal PVC roof repair using IB PVC membrane in West Hartford, CT:

Sarnafil PVC roof repair using IB PVC membrane in Needham, MA:

If you like the work we do, and need to replace your old roof or install a new flat or metal roof, or need a rubber or PVC roof repair done, request a roofing estimate, and get a free roofing price quote – click the Roofing Estimate button below or call us at 617-444-9020.

Flat roof installation sequence and the way different components are put together can oftentimes be quite confusing. We also get many similar questions about particular aspects of how the roof detail work in different situations. To answer these questions and to demonstrate the step by step process of installing IB PVC flat roofing system, we are posting this quick roof installation guide. We welcome any questions you may have – you can ask them in the comments section at the end of this article.

Installing a flat roof (PVC single ply roofing membrane in this case) can be a pretty straight forward process, or a very confusing endeavor because each component must be installed in a particular order. Otherwise the system may not work the way it should. Of course there is an installation spec manual from IB roofs, which we always keep handy, and actually had to use once or twice. However, this manual only shows particular flashing detail or a general way of how membrane and insulation ought to be installed. It can’t possibly cover all the specifics of the roof installation that come up in the field.

Flat roof installation – mechanically attached assembly:

A reinforce PVC single ply roof allows installers a choice of installing the roof in a fully adhered assembly (sheets of membrane glued to the insulation) or a mechanically attached assembly where each sheet or roll of the roofing material is screwed to the roof deck substrate with heavy duty, corrosion resistant roofing fasteners, and barbed plates. Each roll is screwed to the roof deck on one side, and then the next roll, overlaps a row of screws, and is welded to the first roof, right next to the screws. Then the process continues in the same manner until the whole roof is covered by the membrane.

As you can see in the roof installation picture above, the narrow roll of membrane is installed around the roof perimeter and wider rolls are in place, and are ready to be installed. However, before you get to this point, there is a lot of prep work that has to be done first, and the actual membrane installation is the easy part.

Lets start looking at the prep work, and the order in which things actually happen.

Flat roof installation – prep work – insulation, wood nailer and penetration flashing.

PVC Roofing is a very durable and long lasting flat roofing material. However it should never be in direct contact with any oil and asphalt (also oil) products, and since most other roofing materials are made with oil or asphalt, we always install a protection layer between PVC membrane and either old roof or the roof deck. We usually use insulation to protect the membrane from being in contact with asphalt and also from deck fastener punctures. Roof insulation also serves its primary purpose of improving thermal insulation properties of your roof.

Before we install insulation though, we first install a perimeter wood nailer that serves as a rigid nailing base for the PVC-coated drip edge. Once wood nailer is in place, we lay out the insulation sheets and fasten them to the roof deck, using FM Global 60 or 90 mph wind rating standard – 8 or 10 plates + fasteners per 8×4 feet insulation board (although this is unnecessary, since it is a mechanically attached system). Once the wood nailer and insulation are in place, we install one or more rows of perimeter half sheet, which is a 3 foot wide roll of membrane, vs and standard 6 feet width for field rolls. The perimeter half sheet is installed to prevent wind uplift, and is fastened either 12″ o.c. or 6′ o.c. (for high wind areas).

Flat roofing – tapered insulation:

If there is a ponding water situation, the fastest and most cost-effective way to solve the ponding is to install a so called tapered insulation system, which creates slight roof pitch, which helps divert the water in a required direction and improves roof drainage.

Tapered insulation is basically the same thing as extruded PolyISO insulation with a fiberglass facing. The only difference is that tapered insulation is wider along one edge and narrower along the other. Tapered insulation system can have a roof slope ranging from 1/8″ per one foot run, to 1/2″ rise per one foot run or more. Normally we use a 1/4″ tapered insulation system which raises roof level 1″ for every 4×4′ insulation piece.

Flat roof installation – drip edge detail:

As we mentioned the perimeter half sheet is installed along roof edges, and fastened on the inside with screws and plates – what is holding the half sheet along its outer edge? Well, this is the question that homeowners often ask me. The way IB PVC roof system is designed, allows us to attach the outer edge either directly to the drip edge or run in over the roof edge by a couple of inches, nail it to the fascia board and install a drip edge metal over the membrane.

Both ways are acceptable, but most of the time we use the second method – especially in high winds area. Once the roofing material is installed and flipped down, over the edge of the roof, we install 10 foot sections of 22 ga PVC coated galvanized or stainless steel drip edge, and fasten it to the deck with the roofing screws, either 12″ or 6″ o.c. Then we weld a 5″ wide cover strip of the membrane to the roof and to the drip edge, to seal the screw holes and bake the whole detail water-tight.

Check out our video on how drip-edge metal is installed:

Once the 10-foot sections of drip-edge are installed, the joins are sealed using an aluminum tape and a PVC patch to mack the joint water-tight and protect the patch from metal expansion and contraction. After the joints are complete, the cover tape is welded to drip edge starter and the roof itself, and its now time to do the rest of the roof.

As a side note, there are many options for drip edge detail. Although the most used drip edge is the 2 or 3″ wide face, white starter, you can also choose it to be as much as 8 or more inches wide, as well as in gravel stop style (if you need to divert the water flow or prevent it from going over the edge of the roof.

Gravel stop drip edge has a 1″ bump-out, which stops water from spilling over, and makes it run down the roof – toward a drain or a gutter. Drip edge comes in two colors – white and dark bronze, and also can be painted any other color with acrylic paint. IB roofs also offers 16 oz. copper drip edge, with PVC material adhered to the flange, and can produce any style drip edge, with different angles, kick-in or kick-out face and in various widths.

Flat roof installation – field sheets, roof penetrations and roof to wall termination:

After all edge detail is complete, we install the field rolls of membrane and all penetration flashings, such as pipes, drains, HVAC / Skylight curbs, roof hatches, chimneys, etc.

IB Roof Systems produces a wide variety of flashing accessories, which allow installers to quickly and easily flash almost any roof penetration. Since all roof components are made of PVC, they are all welded together, and the use of any adhesives or glues is completely eliminated, as well as most installation errors by roof mechanics.

All curb and up-the wall flashing is installed using a two-step process. First, the roof is terminated that the wall, and then a separate piece of membrane is installed up the wall and welded to the roof.

After the flashing is installed and welded to the roof, the inside or outside corner flashing is welded to make a permanent watertight joint.

All IB flashing accessories are made of 60-mil non-reinforced flashing membrane and can stretch to perfectly adhere to any shape of a penetration on the roof. Pipe flashings and drains have a reinforced flange to be welded to the roof.

Bellow is a video demonstrating the curb flashing installation around a skylight:

As you can see in the video, the roof penetration flashing is a very clean process, and a chance of a leak is minimum to non. Unlike flashing details on a rubber roof, where a membrane cannot and should not be terminated at the base of the curb, due to high possibility of a leak caused by adhesive failure, the hot air welding process used in sealing overlaps and seams on a PVC roof, eliminates leaks, as well as membrane pull-out caused by contraction of the roofing material in cold weather.

Flat roof installation – special flashing details:

IB roof spec manual does not cover all installation details, as in the real world you often run into situations where you have to “improvise”, while your roof must still be watertight. One such example is the ridge vent detail on flat / low slope roofs such as shed dormers. While many low slope roofs are considered “flat”, they were built as sloped roofs with ridge / soffit ventilation in mind. However, many roofing contractors that install EPDM rubber roofs, block the ridge vent opening completely to prevent roof leaks.

We’ve developed a special assembly method, which allows us to still use the ridge vent, and keep the roof watertight. We run our roof up-to the ridge opening, weld additional strip of membrane, install a 2×4 wood to raise the level off the roof, flip the strip of membrane back and wrap the 2×4 with it. This prevents wind driven water from penetrating the roof, and ridge vent + ridge cap is installed on top, 2 inches up.

As you can see, IB PVC roof can be adjusted to virtually any type of flat roof, and roof penetrations. We recommend that you check out more roof installation videos on our Roofing Videos channel on YouTube.

You can see more examples of flat roof installations that we have done all over New England: Roofing in Massachusetts and roofs in Connecticut. We provide residential roofing and commercial roof installation services in all New England states. However most of our work takes place in MA, CT and RI.

Also, if you have a flat roof deck that is leaking, check out our roof deck section, to learn more about IB roof installation on flat roof decks, patios and balconies, using special slip-proof roofing material called IB DeckShield.