When deciding on what type of material to use for a commercial roof between TPO and PVC, one of the first determining factors is the cost.

Grant

A flat roof replacement is a big investment for facilities managers and business owners throughout the region, and the first big decision that has to be made is what single-ply membrane to select. Of the many options, TPO and PVC are the most common roofing choices for warehouses and big box stores. While TPO and PVC appear similar, their distinctions in performance and cost are important considerations when thinking of the lifespan of the building. Recognising their differences helps a specifier decide the best choice for their building.

What Is TPO Roofing?

TPO is a flexible, budget-friendly, and long-lasting membrane that has gained traction with commercial and industrial rooftops. TPO has the added benefit of reflecting heat back and reducing cooling costs for large warehouses and distribution facilities. The seams of TPO roofing membranes are welded while on site with hot air, thus creating a sealed and continuous barrier against water. TPO is also quite puncture resistant as industrial and commercial rooftops are usually in close proximity to HVAC systems.

What Is PVC Roofing?

Polyvinyl chloride (PVC) roofing systems possess unique stain resistance and are ideal for applications with grease, oil, and chemical exposure such as restaurants, food processing facilities, and industrial processing units. PVC roofing systems include heat-welded membranes that form highly dependable and reliable seams. While the initial cost of a PVC roof is typically more than a TPO roof, many facility managers believe that the increased cost is justified when chemical exposure is a primary concern.

Key Considerations for Facilities Managers

Choosing between the materials is mostly situational depending on the specific building. Environments with kitchen extraction, oil manufacturing processes, and chemical storage proximity resolve to use PVC for its superior resistance to such substances. Warehouses and distribution units valuing thermal performance and being budget-conscious tend to go with TPO, especially in cases of large, flat roofs, since reflectivity matters a lot for inner building temperature control. The age of the roof, type and current state of roof insulation, roof drainage, and the client’s intended use for the building in the future are also relevant in the decision analysis. A thorough commercial roofing assessment is needed before deciding on any material.

Installation and Long-Term Maintenance

Like any other installation, trained personnel are required for both membranes, since the quality of welded seams is entirely dependent on the installers. Poor welds are the main cause of leaks, and are found not only in inferior systems, but more often in better systems; poor welds can lead to leaks in even the best systems. A planned maintenance schedule that includes semi-annual or annual inspections of seams, flashings, and roof penetrations will prolong the working life of either system. As with most things, neglecting to perform the planned maintenance results in issues that can lead to major problems. Lifted seams and damaged flashing can lead to major damage before a leak is noticed.

Getting the Right Advice

In the end, there are no perfect answers for every commercial or industrial building. A roofing contractor with experience will look at how the building is used, how exposed the building is to chemicals, oils, and budget, then suggest TPO or PVC. For businesses planning a re-roof or new building project, getting that right assessment at the start saves money on re-work in the future and ensures the membrane performs to the expected satisfaction for the life of the building. Making this decision now may even save money on maintenance that it would otherwise cost in the future, and reduces disruption to normal day-to-day operations.

Industrial Roof Replacement

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Industrial roof replacement is unlike domestic or commercial work. Industrial roof replacement involves larger scale, complex access, demanding health and safety requirements, and significant consequences when things go wrong.

Roof replacement on industrial buildings is mostly done when the roof is profiled metal sheeting systems with or without single-skin liners and insulation gaps. Some of the older industrial buildings have built-up felt or asphalt on a concrete or steel deck.

Strip and Replace versus Overcladding

The replacement of industrial building roofs involves the removal of the existing roof and the placement of a new roof on the existing roof support (strip and replace) or the placement of a new roof on the existing roof (overcladding).

Large industrial roofs require the application of the Overcladding method. It is less disruptive than the removal of the current roof, maintains the containment of the facility during the roof work, and eliminates the disposal costs of the existing upper metal rodding.

Since the present arrangement already supports I-beams, there will be an additional structural load, necessitating an evaluation of structural integrity before proceeding. However, in the case of a robust structure, it is what is typically preferred, as well as the more economical option. The choice of ‘strip and replace’ is correct when the existing sheeting has deteriorated past the point of being acceptable for overlayment. It is also the option when there exists a structural failure of the sheeting that requires deconstruction and remediation at the level of rafters, or in the event that the client desires a change in the roof profile together with a replacement of the roof and improvement of the structural deck.

Health and Safety on Industrial Sites

Working on an industrial roof brings specific health and safety requirements. Edge protection, working platform systems, and in some cases full scaffolding are standard. For roofs with fragile materials — older profiled sheeting, rooflights that are no longer load-bearing, areas of corrosion — additional protection measures are needed both for the operatives and for anyone working below.

We operate under documented RAMS (Risk Assessments and Method Statements) for every industrial roofing project. These are produced in advance and can be submitted for client approval before work starts. We work within permit-to-work systems on sites that require them and participate in site inductions as a matter of course.

If asbestos-containing materials are present — older cement fibre sheeting, asbestos insulation board, asbestos-containing flashings — a licensed asbestos contractor needs to be involved before any stripping work begins. We can coordinate this as part of the project or work alongside a specialist you’ve already appointed.

Commercial Roofing Materials and Fire Safety

Grant

The materials used to build an office, warehouse, or industrial roof can significantly impact a building’s fire performance, including how quickly the fire spreads and what protections are available to occupants and nearby structures. However, commercial roofing fire safety is typically overlooked until something goes wrong.

The UK Commercial roofing industry is influenced by the stratified nature of the Building Regulations and Approved Document B as well as British Standards like BS 476 and the more recent BS EN 13501 fire classification. These laws and regulations determine how roof covering materials respond to fire as well as the External fire spread and Surface spread of flame. With regard to roofing systems, the external fire safety performance is very critical since a covering that is easily ignitable or spreads flame quickly can transform what would have been a minor incident into a major disaster.

In recent years, the discussion surrounding the use of certain insulation and roofing membrane combinations, especially involving PIR (polyisocyanurate) insulation boards, has intensified. PIR provides great thermal performance, but its fire behaviour varies depending on how it is installed, what kind of facing is used, and whether it is sufficiently protected by fire-rated boards or membranes above and below. Getting this detail wrong can result in a roof build-up that, while using individually compliant products, fails as a system.

When it comes to commercial and industrial roofing, landlords and insurers typically use the BROOF(t4) classification under BS EN 13501-5 as a benchmark. This classification means that the roof system, which is tested as a complete unit rather than separate components, does not allow for the spread of an external fire, nor does it cause a significant increase to the fire. For compliance purposes and to make insurers happy afterwards, it is necessary to keep Broof(t4) documents that show the exact build-up construction that was installed.

Along with structural fire safety, insurance is becoming an increasing issue. Many commercial property insurers are now requiring insured parties to show proof of fire-rated roofing systems. This is especially true for large industrial units or large buildings that hold combustible stock. A roof that is poorly specified, ageing, or unknown in its fire performance will likely result in higher insurance premiums, exclusions, and in some cases a total loss of coverage. Many business owners do not realize that the replacement or refurbishment of a roof is just as much of a risk management decision as it is a maintenance decision.

Other than the materials used, detailing around roof penetrations, rooflights, ventilation units, and the intersections between different roof sections are also crucial for fire safety. Unprotected gaps or penetrations that are poorly sealed may provide pathways for fire and smoke to travel through compartments, bypassing the best specified roof covering. Any knowledgeable commercial roofing contractor should be able to show how these details are addressed and should be able to provide compliance documentation as part of the works.

When business owners plan to do a re-roof or major repairs, there are a few important things to keep in mind. First, insist that BROOF(t4) systems be used for the full build-up. Second, request test certificates from the manufacturer that are specific to your roof design. Finally, check with your insurer to see what their requirements are before the work gets started, not after a claim has been filed. Getting professional advice early saves you from costly surprises and ensures both compliance and coverage.

Commercial Roof Repairs

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Commercial roof necessary repairs fundamentally stem from poorly built seam and lap seals; incomplete, poorly installed, or missing flashing; clogged or damaged drainage systems; corrosion at metal roof fixing points; and damage from people walking on the roof or installation of rooftop equipment. The cause of the problems at the rooftop dictates the repairs to be carried out.

We handle repairs for all commercial roof systems we install including single-ply, felt, liquid-coated, and metal. We also repair systems we have not installed including older built-up felt roofs, modified bitumen systems, and existing profiled metal roofs from other contractors.

Getting to the Right Diagnosis

The largest visible consequence of a roof problem is almost always the presence of water inside the building. This is usually not the cause of the problem. Water has to be trapped for an extended period of time and is likely to enter at one location and, then, travel across the roof covering, across the deck, and then find an exit through the ceiling. The most critical step in repairing a roof is not the actual repair but to find the source.

We do not charge for a formal assessment to identify the problem along with an out of pocket actual repair. Our philosophy is simple. The survey and the repair are priced separately. If the survey finds something more significant than a straightforward repair, we are obligated to identify the issue and provide appropriate options.

Reactive Repairs

In critical repairs, such as leaking roofs, storm damage, or lost cover, we will as quickly as possible, address the condition, as the fastest option will be able to make the condition watertight. In some situations, this will mean doing the repair in multiple stages. We will be transparent about what is involved in what we will do and what the follow on work is.

Planned Repairs

Not all repairs are urgent. Commercial roofs are examined for repairs. Commercial roofs will develop issues. Inspections will leave issues on the roof that spill into the interior. We want to fix these issues before the water damage enters the room, as we will lose money inside the building.

You will spend more money and leave the roofs in worse repair if you do not enter into a program that is preventative if you have a planned maintenance portfolio. We are happy to work with you to tailor a program to your portfolio.

Condition Reports

In the instance that we are, we are happy to develop condition reports of the roofs. We will not tell you to replace the roof. These roof reports have various uses. We will describe the roof in its current state, its current state. the various sections of the roof. We will describe the current state of the roof in various sections.

Metal Roofing

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Metal roofing is commonly found on most commercial and industrial buildings, such as architect designed offices with standing seam aluminum and logistics warehouses with profiled steel sheeting. Although the materials and profiles may differ, the strategies for installation, weathering, and maintenance are the same.

Metal roofing systems are configured, designed, and built for many commercial and light industrial facilities. This includes systems for new builds, overclad systems on existing roofs, and systems for the complete removal and replacement of failed/end-of-life systems the building may have.

Standing Seam

Standing seam systems are designed as concealment systems, meaning the areas where the joint and the fastener interact are concealed. They are more concealed than sys that actually penetrate through the surface of the sheeting. The failure point of fasteners is removed, and therefore, standing seam systems are less susceptible to failure. Water ingress is a consideration and a properly designed standing seam reflects this, as there are designed are none.

Where the roof is only partially visible and may have an architectural design, this is where a standing seam is most appropriate over a large spans of profiled steel. Because there is and continues to be no capability to paint or place exterior protective coatings, weathering is left to nature, hence roof systems with aluminum and zinc are preferred. Since the systems are mainly aluminum, contracts and expansions are significant.

Standing seam systems require a considerable amount of precision and there is a considerable amount of flexibility that is required to preclude bending and/or deforming of the standing seam roof and to accommodate the substantial deviation that is expected.

Folding Metal Sheets

Folding steel and aluminum plates are almost the standard covering for large industrial and commercial buildings. Easy to install on large surfaces, available in a variety of profiles and colors, and with the correct specification, they can be expected to last more than 25 years.

The most important factor is the specification of the sheet — coating, steel grade, and thickness. A commercial building with a 30-year design life should not have the lightest grade materials as the roofing sheets. We let the project’s requirements guide the specifications, rather than the price. As a result, the quotations will be very clear.

Screw fixings determine the quality of the sheet and the metal sheet roof. Roof sheets are usually secured to the purlins with self-tapping screws. The quality of the screws and, in particular, the sealing through the purlins with screwing screws are some of the first elements to fail on a metal roof. On a roof in otherwise good condition, a screw inspection and replacement program can greatly extend the service life before a complete replacement is required.

Overcladding

Overcladding means providing a new metal sheet system on top of an old one instead of removing and replacing an old metal roofing system. It saves the removal and disposal costs, maintains the integrity of the building during replacement, and often allows the workspace to be used.

It isn’t appropriate for every situation. The current structure needs to be examined to ensure it can accommodate the additional weight. Any signs of severe corrosion or structural collapse on the existing sheeting should be resolved before implementing this solution. However, on a large industrial or commercial structure where the existing roofing is failing but not completely, this is a solution worth looking into.

Commercial Roof Maintenance Contracts: Why They Are Worth the Investment

Grant

While roof maintenance jobs may be a nuisance, planned roofing contracts help property owners avoid problems, thereby saving them time and money.

Catching Small Problems Early

Routine maintenance inspections can catch what may appear to be minor problems, like a broken seal around a rooflight or an obstructed drainage outlet, and have them fixed before a full leak occurs, protecting stock, equipment, and office space below. When it comes to commercial property, the costs associated with water damage will typically exceed the costs associated with preventative maintenance by several multiples.

Protecting Warranties

Due to the absence of documented maintenance on file, businesses are exposed to the risk of having warranty coverage missing just when they need it most after storm damage or premature failure of roofing materials.

Budgeting With Confidence

For facilities and finance teams who manage budgets for commercial and industrial premises, the maintenance contract converts unpredictable emergency repair costs into a known, manageable expense, helping with costs and making budgeting easier.

Extending Roof Lifespan

With regular maintenance, commercial flat roof and cladding systems can outlast unmaintained systems by over a decade, thereby saving you a considerable amount of money compared to the cost of early replacement.

What a Good Contract Should Include

Seek a maintenance contract that covers at least two inspections annually, outlet and gutter clearing, a written condition report, and prompt access to repair work when issues are identified.

If your commercial or industrial building still lacks a roof maintenance plan, contact our team to talk about a contract that best fits your property.

New Roof Installation

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New roof installations are most commonly required for extensions, new-build properties, or conversions, whether it be loft, garage, or outbuilding conversions. An installation begins with a structure that has either an absence of or a temporary roof covering.
It differs from a roof replacement in one key aspect: stripping out is not required. An installation begins at the structural level, confirming that the rafters or structural deck is in good condition and correctly specified, followed by underlay, battens, and the covering of choice.

Getting the Specification Right

There are multiple factors to take into account when deciding on the covering of a new installation, such as the building’s roof pitch, the site’s exposure, the architectural style of the building, and any planning considerations. While it is likely that most properties will not have much of a constraint in terms of planning considerations, if the building is listed or it is within a conservation area, there may be limited options for materials. This will be important when coming to a decision.


There are multiple options for pitched roofs: interlocking concrete tiles can be laid to around a 17.5 degree, natural slate will lay to a pitch of at least 25 to 30 degrees depending of the lap, and plain clay tiles require a steeper pitch. If build is built with a pitch that is on the marginal side, we will inform you of the situation sooner rather than later.

Developing and installing flat roofs in home extensions is one of our more standard tasks. We usually use EPDM and GRP for home flat roofs. You can learn more about them on our flat roofs page.

Leadwork and Abutments

Every new roof that abuts an existing wall (an example would be an extension that adjoins the main house) requires lead flashing to weather the joint. Several new installation works can be undermined by proper leadwork, especially with chimney abutments, parapet walls, and rooflights. We do our own leadwork and do not subcontract it. After all, it is a roof and should be treated as such.

Building Regulations

Installing a new roof on an extension will likely require all aspects of Building Regulations to be considered, including structural adequacy, thermal performance, and the spreading of fire. If you’re working with a designer or an architect, this will be accounted for in the specification. If not, we can inform you on all aspects of compliance during the survey and quote.

We do not submit applications for Building Regulations, but we work to specifications that will meet the current requirements to help. We can also give you all the information a Building Control inspector will require.

Considerations When Hiring Flat Roof Roofers for Commercial Buildings

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Most managers give little thought towards the roof of a building until a problem arises. Flat roofs are designed to be low-profile and segregated. However, damage to a flat roof may take a long time to surface, and when it does, it is usually noticeable. An office or store with a busy interior may experience a roof leak that is a problem that has been ignored for too long.

That is why it is important to hire the right staff to take care of flat roof roofers before a problem arises, or before it gets worse. There are many options to choose from when it comes to commercial roofing. So much so, that it is important to keep in mind the consequences of choosing the wrong contractor.

Knowledge is Better than Saving

Consider a system’s knowledge rather than the cost of a roof. There are numerous options when it comes to flat roofing. There are single-ply TPO membranes, PVC membranes, built-up feel systems, inverted, or warm deck construction. There are also many options to choose from when it comes to liquid grow systems. Different systems require different solutions, so from a single systems roofing contractor’s perspective, each job is solvable.

When you analyze quotes, be specific. Propose what system is being used, and why. If the answer is unsatisfactory, or the same system is quoted across every building regardless of their age, status, condition, or purpose, it communicates a trend.

Accreditation and Insurance — What to Consider

When it comes to commercial contracts, there are some things that are desirable and others that are not. A CHAS health and safety certificate or a health and safety certificate of the same status and procedure is the bare minimum. It confirms that the contractor’s health and safety practices have been examined and evaluated. It is a requisite for a number of supervised facilities and should be implemented for others.

The NFRC stands for the National Federation of Roofing Contractors and is the primary umbrella trade organization in the UK for the roofing trade. If a contractor is a member, it indicates that they are part of the professional body and are therefore accountable (though it does not mean that the contractor will provide high quality service).

It is important to make sure that the public liability insurance is appropriate for commercial projects. For a large flat roof project on a commercial building, the insurance coverage should be higher than the contract value and should take into consideration the value of the building and the contents. Please provide the insurance certificate and make sure that the coverage is appropriate and that the insurance is not old.

It is important to consider the benefits of manufacturer-approved installer status when dealing with single-ply systems. Most of the primary membrane manufacturers provide 15 to 25 years of extended warranties, but only if the system is installed per the manufacturer’s instructions by an approved contractor. An approved installer gains exclusive technical support from the manufacturer if issues arise.

What a Proper Survey Looks Like

Flat roofers who are worthy of hiring are going to want to do an in-person assessment of the roof before they provide a quote. For a commercial building, this assessment is mandatory. The deck condition, the drainage, the built-in slopes, any rooftop obstructions, rooftop plants, and the current state of flashings and upstands, are all going to impact what the quote looks like. Any quote that is generated from images or building schematics is going to be a very educated guess.

The survey should produce a condition report, and a quote should include a detailed specification system that states the type of material, how thick the system will be, and how the drainage will be handled. It should include explanation for the upstands and the perimeter. You create opportunities to compare quotes if all the details are provided. Identifying and holding the contractor accountable for deviations from the agreed-to end product is equally important.

Maintenance Contracts and Long-Term Costs

Do not underestimate maintaining a large commercial flat roof. Warranties on most membrane systems stipulate inspections are maintained to keep the warranty valid. Inspections should be done every one to two years. They identify potential leaks (like a blocked outlet or loose roofing materials) and prevent them from becoming a larger issues.

Flat roofing companies with experience in the industry will include maintenance contracts with installation. Planned maintenance contracts are a time-saver and alleviate the headache of managing maintenance budgets at multiple properties.

A Note on Emergency Repairs

Prompt care is critical for active leaks in a commercial property. Some situations will inevitably require a temporary repair for the sake of protecting the building’s (and tenants) interior. Be cautious of those who will insist on an entire roofing replacement almost immediately. A sequence of a temporary repair followed by a report of the building’s condition and a permanent fix is a nice course of action for the situation.

Flat Roof Frameworks — Single-Ply, Built-Up Felt & Fluid Coatings

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Flat roofs can be found atop many structures, from retail units to school buildings to apartments and distribution centers, to name a few. Each structure’s flat roofs have different usage and design requirements. Considerations include available budget for installation and long-term maintenance, the roof’s design and the equipment it will hold, the volume of foot traffic the roof will receive, and the roof’s shape and structure, among many others. Most of the three systems commercial roofs utilize the most are single-ply membranes, built-up felt, and liquid coatings. Each system is more applicable in different situations.

Single-Ply Membranes

Without deviation, single-ply is the best option for commercial flat roofs, with the exception of built-up roofs. All single-ply roofs use one of the two most popular membranes – TPO or PVC. Membranes are inherently flat and are placed in huge sheets atop a roof. Unlike built-up systems with many horizontal seams, a single-ply system’s seams are almost completely replaced by one continuous weld seam. With this in mind, built-up systems inherently struggle with roofs large enough to require many horizontal seams, unlike single-ply systems, which further struggle with many seams. On a built-up system, each horizontal seam is a transition between roof elements which potentially introduces a point of failure to the system.

PVC is more established in the UK and is chosen for roofs that come in contact with chemicals, like industrial settings and kitchen exhaust zones. Both systems are offered with long manufacturer warranties, including 15 to 25 years, on the membrane, if the installation is done by an authorized installer to the manufacturer’s directions. We are authorized to install under the warranties of several major manufacturers and will decide which one is correct for your project during the specification phase.

Built-up Felt (BUR) Built-up felt systems have been developed and used in many commercial buildings, and in modern times, more high-performing options are available. It is the practice of assembling the same thickness and the same system of different layers of bitumen and impregnated felt together, forming the built-up system. They are systems that have been vetted on commercial buildings with lower pitched roofs and those with complex roof drainage and/or those with irregular roof substrate. It is also one of the cheapest systems among the options available for built-up roofs, allowing it to be proposed to more commercial buildings that will are restricted by budget.

We do not skimp on suggested prep work and number of application layers. Liquid CoatingsLiquid roofing systems are applied with a brush or roller and cure to become a seamless waterproof surface. While not usually used as a primary roofing system on a large commercial roof from scratch, they have their benefits in certain situations.The most popular use is refurbishment, or the use of an existing flat roof that has structural integrity but surface issues, such as deterioration, cracking and failing lap joints.

Liquid Coatings applied to a pre-prepared surface can extend the existing flat roof’s surface life, without the inconvenience of a full tear-off replacement. On large commercial buildings, this is a big deal. Liquid systems are also helpful detailing around various commercial building features such as, drainage outlets, pipe penetrations, and upstand junctions, where a roof coating system is typically not used, due to system ‘neatness’ issues. Liquid roofing coatings can sometimes be used in such instances in conjunction with a wider single-ply or felt roofing system.

The most popular liquid roofing systems on commercial buildings are polyurethanes and PMMA (polymethyl methacrylate) liquid systems. PMMA also has the shortest cure time, and can in fact cure in an hour, which is an advantage for occupied buildings, where you have to have a waterproof roof by the end of the workday.

Roof Replacement

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Roof repairs can be inordinately costly. If you are overlooking the same problem repeatedly, repairs add up unexpectedly. If you are surveying the roof repairs and they are marking the same area over and over, it can be financially sensible and arguably easier to replace the roof rather than to keep repairing it. Even if the cost of replacement is greater, replacement can be the more financially reasonable option.

There are multiple signs that indicate a roof has officially reached the replacement territory. Missing or dislocated tiles can still be manageable, but if tiles become brittle and the moisture seeps into the roof’s void, there is little more to be done. After repeatedly repairing a flat roof and it still absorbs water, it can become necessary to remove the roof completely.

What Roof Replacement Involves


Complete roof replacement entails completely removing all of the roof’s tiles, battens, and felt down to the rafters. Replacement reveals the roof’s rafter structure and exposed timber, which can be upgraded, and replacement is also an upgrade. Replacement also means the upgrading of the roof’s membrane and its underlay. Contemporary underlay is breathable while battens are not. It can be worthwhile to think about material choices for replacement. Many roofs can be cement tiles, for example, but replacement allows the line(s) to be improved. Natural slate is superior to concrete and can improve the roof.

There are implications on both the structure and the weight of the building when the material used is changed. We will consider that in the survey and specification.

How Long It Takes

Typically, a semi-detached or a detached house will show multiple semi-detached roofs with similar features and will take between three and five days. Properties with a number of roof planes and components take longer. We will provide a realistic program before the work begins, so do not expect a more positive message. Removal and disposal of the old materialAll of the materials that have been removed will not be kept on the site and will be legally disposed.

We have a current license to carry waste. If you are concerned about asbestos-related materials, some of the cement roof sheeting and some of the older flashing materials can contain asbestos, and we will carry out a survey before the stripping is done. If asbestos is disturbed without a survey, it is a legal issue, so we do consider it a precaution.

Your guarantees pertaining to the warranty on your new roof will be included in your new building code. The quality of the material and the specifications used to build your roof are important for us to assess in the provisions we are making to protect the warranty. Tile and slate material manufacturers tend to have a warranty on their newer products. It is important for you to compare the quotes in the same layers of the material rankings and the warranty about the removal of the materials, and the prospects that accompany these assessments, because a quote that is cheaper while using materials on the lower end of the grading system, and is not cheaper, while including the removal of the ridge and hip work, is not actually a quote that has cheaper work involved.