"roof forms"

A question that homeowners often ask about steel roofing is “Will a steel roof be noisy when it rains?”. We’ve created this fact sheet to help answer that question. Residential steel roofing is available in many shapes and forms. The forming process provides not only strength, but when coupled with high quality build finishes, absorbs and deadens much of the noise. With the home insulation standards of today, you should not notice any difference in noise levels between roofing materials. 

Steel has been used in North American construction projects for more than 150 years and still remains one of the strongest, most durable and economical building materials available today. Although steel has been traditionally associated with high-rise buildings, bridge structures and commercial and industrial projects, it is rapidly emerging as the logical material of choice for residential construction. Cold formed sheet steel panels are lightweight, economical, easy to handle and represent a high quality alternative to traditional roofing materials. Environmental and economic considerations have prompted many residential homeowners to investigate alternative building materials and methods, and steel roofing panels have proven technical benefits as well as excellent recycling capabilities which make them an increasingly popular choice. This follows the long-time use of steel roofing in commercial construction where steel has built undisputable quality and performance records. 

When a homeowner is considering the purchase of a steel roof a common question is whether it will increase the risk of a lightning strike. After all, steel is highly conductive, just like the materials used in lightning rods, so doesn’t it stand to reason that the steel roof will attract lightning? The short answer is, NO, steel roofing will NOT increase the risk of a lightning strike in any way. For all intents and purposes, nothing ‘attracts’ lightning. Lightning occurs on too large of a scale to be influenced by small objects on the ground, including steel roofs. The location of the thunderstorm overhead alone determines where lightning will hit the ground. A lightning bolt that is several miles long, generated by a cloud that is more than 6 to 10 miles high, is not going to be influenced by an object the size of your house. 652 Bishop St. N., Unit 2A, Cambridge, Ontario N3H 4V6 • Tel.: (519) 650-1285 • Fax: (519) 650-8081 • www.cssbi.ca The descending stepped leader of a lightning bolt doesn’t ‘decide what to strike’ until it is very close to the ground. When a cloud-to-ground lightning channel is forming, it is going to strike the ground where the opposing charges are greatest, directly underneath the storm’s most electrically active region. If you are standing at that exact location, you will be hit, even if there’s no metal within miles! Conversely, if you are farther than 500 feet from that location, you could wave your golf club or umbrella high in the air, but you won’t draw the lightning away, even slightly, from striking where it’s going to strike. Steel does conduct electricity, but steel roofs don’t attract lightning or increase the probability of a lightning strike. Four factors affect the probability of a lightning strike: • Topography: a structure located on a mountain or hill has a higher probability of a strike than one in a field. • Structure size and height: a tall structure or one that covers a great deal of ground has a higher probability of a strike than a short or small building. • Relative location in relation to taller structures: a small, short building near a taller structure has a lower probability of strike than the taller structure. • Severity and frequency of thunderstorms in the structure’s vicinity. However, on occasion, lightning does strike a house. If your home were hit, the steel roofing would disperse the energy safely through the structure. Since steel roofing isn’t combustible or flammable, it’s a low risk and desirable roofing option where severe weather is concerned -- especially for lightning. For More Information For additional information on steel roofing or other sheet steel building products, visit our website at www.cssbi.ca.

Environmental Product Declaration Roll Formed Steel Panels

This Awkward Passivhaus design barrel roof made airtight with ease with Spray applied Airtight vapour control membrane Passive Purple.

Buildings consume one-third of all energy and two-thirds of all electricity generated. Cool metal roofs can help reduce energy consumption by lowering cooling loads with their wide array of finishes, designs and colors.Cool metal roofs are energy-efficient. • The roof can have the greatest impact on the energy use of a building. On a typical summer afternoon, a light-colored, more reflective roof that reflects 80 percent of sunlight will stay about 310C (550F) cooler than a darker roof that reflects only 20 percent of sunlight, as reported by the Heat Island Group of the Lawrence Berkeley National Laboratory. • Cool metal roofs are an excellent option for commercial retrofit applications because they can be efficiently installed with above-sheathing ventilation, allowing heat to dissipate through the ridge vent in hot weather while acting as an insulating layer when it is cold. Metal roofs can result in as much as a 30 percent reduction in heat gain through the vented roof. • Metal roofs provide the optimal foundation for photovoltaic installations since the roof can be expected to last longer than the PV system it supports. • Wall and roof solar heat recovery systems can be integrated with steel cladding and used to provide air, water or process heating needs. • Cool metal roofing is available unpainted, with thermosetting coil-applied paint finishes, or with granular-coated surfaces. This family of roofing can achieve solar reflectance of over 70 percent, meeting the EPA Energy Star Roof Products Program performance criteria. • Emittance as high as 90 percent can be achieved for painted and granular-coated metal roofing. • Painted metal roofs retain 95 percent of their initial reflectance and emittance over time. They resist the growth of organic matter and shed dirt more readily than other materials. • Cool metal roofing can help to mitigate the Urban Heat Island Effect because of its high reflectance, which can reduce ambient air temperatures. Cool metal roofs are cost-effective. • Metal roofing has low life-cycle costs, making it the choice of many school, government, commercial, industrial and institutional building owners. • Due to its light weight per unit area, structural savings can be realized in a building when compared with heavier non-metal roofing alternatives. • For re-roofing projects, metal roofing can often be applied over the original roof, saving removal and disposal costs. • Metal roofing is fully recyclable when ultimately removed as part of building renovation or demolition, allowing it to credibly claim both recycled content and 100 percent recyclability by recognized definitions. The product’s recyclability also provides significant savings on construction removal and disposal costs.

It’s a fact that buildings consume two thirds of all the electricity produced in North America and one third of all the energy produced in North America. While it is recognized that adding insulation under the roof surface can reduce cooling and heating costs, there is a diminishing return on the strategy of increasing insulation to conserve energy costs. This is where “cool roofing” can play a role in further reducing the energy consumed, and in minimizing the Heat Island effect created in the big urban cities. Cool roofing relies on sustainable, energy efficient, coated steel products, in a wide variety of finishes, colours, textures and roofing profiles. It conserves energy through its properties of reflectivity and emissivity

An independent assessment of the life cycle cost for various low slope roof systems revealed that steel roofing had the longest life span, no leaks due to material failures, and the lowest overall maintenance cost.

One of the most common questions asked by homeowners about the installation of their steel roof is whether an underlayment is needed. The answer to this question is “yes” in most situations. The underlayment plays a critical role in controlling the migration of condensation that might develop on the underside of the steel sheet thereby preventing accumulated water entering the building resulting in costly damage.

PREFACE One of the objectives of the Canadian Sheet Steel Building Institute is the development of product standards to promote sound construction using safe building practices. This Standard is intended to further this objective by providing to buyers, manufacturers and installers of steel farm roofing and siding, information which can be used or adopted by reference where desired. The requirements contained herein are in accordance with accepted engineering principles, augmented by experience. They include recommendations covering steel thicknesses, minimum metallic coating designations, as well as design, manufacture and installation in general.

Introduction Sheet steel roofing and siding (cladding) is available in a wide variety of profiles, colours and paint systems. The modern prepainted systems used on Canadian-made products will provide decades of beautiful performance before there are any visible signs of deterioration of the paint surface. However, an important component of the cladding system is the fastener used to attach it to the structure. This fastener is not simply a screw; it is part of the roof or wall assembly and should be expected to provide the same long-term performance. This performance is not simply the capacity to safely hold the cladding in place, but also to match the colour and durability of the paint system. The selection of the correct screw for the job is the first step in the creation of a cladding system that will provide long-term performance. The next step is the installation. Installing screws in sheet steel cladding is commonplace and can be done very efficiently. The tool manufacturers have developed a wide range of options for installing fasteners into any type of substrate. Selecting the most appropriate tool will help the installation process.

Preface One of the objectives of the CSSBI and its members is the development of standards and technical publications that promote safety, performance and good practice. This "How To Series" of publications is an educational tool intended to give guidance to anyone specifying sheet steel building products. This particular publication is published as an aid to building owners as well as roofing and siding installers. It offers simple and practical recommendations for the selection, application and installation of light gauge steel cladding. This is a generic guide giving the basic details and should only supplement the specific recommendations or guidance published by the manufacturer appropriate to their own products. The views expressed in this guide are a collection of installation techniques and do not necessarily reflect those of all member companies of the CANADIAN SHEET STEEL BUILDING INSTITUTE. The material presented in this publication has been prepared for the general information of the reader. While the material is believed to be technically correct and in accordance with recognized good practice at the time of publication, it should not be used without first securing competent advice with respect to its suitability for any specific application. Neither the CANADIAN SHEET STEEL BUILDING INSTITUTE nor its Members warrant or assume liability for the suitability of this bulletin for any general or particular application.

PREFACE One of the objectives of the Canadian Sheet Steel Building Institute is the development of product standards to promote safety and sound construction practices. This Standard is intended to assist specifiers, designers, buyers, manufacturers, and erectors of sheet steel cladding by providing information which can be adopted by reference where desired. The requirements contained herein are in accordance with sound engineering principles, augmented by experience. They include recommended minimum requirements for such factors as grade of steel, thickness, metallic coating designation, loading and deflections, as well as design, fabrication and erection in general. While the material is believed to be technically correct and in accordance with recognized practice at the time of publication it does not obviate the need to determine its suitability for a given situation. Neither the Canadian Sheet Steel Building Institute nor its members warrant or assume liability for the suitability of the material for any general or particular application. 

Introduction Most cold formed steel building products, whether painted or unpainted, are manufactured from a sheet steel material that has some form of metallic coating applied. This metallic coating can be zinc (galvanized), zinc-iron alloy (galvanneal) or a 55% aluminum-zinc alloy (GalvalumeTM). The metallic coating is available in a range of thicknesses to provide the degree of corrosion protection and service life required. One of the concerns expressed by installers relates to the presence of wet storage staining on the products, how this staining impacts the long term performance, and what can be done to remove it. The purpose of this fact sheet is to address some of these issues, allay some fears, and give guidance on proper storage techniques.

It’s a fact that buildings consume two thirds of all the electricity produced in North America and one third of all the energy produced in North America. While it is recognized that cooling and heating costs can be reduced by adding insulation under the roof surface, there is a diminishing return on the strategy of increasing insulation to conserve energy costs. This is where “cool roofing” can play a role in further reducing the energy consumed, and in minimizing the Heat Island effect created in the big urban cities. Cool roofing relies on the properties of reflectivity and emissivity of the roofing material. Reflectivity Reflectivity is the ability of the roof to reflect solar radiation back into the atmosphere. Its primary measure is solar reflectance - the proportion of the total solar radiation that is reflected back to the atmosphere. Any solar radiation that is not reflected is absorbed into the building envelope, requiring further energy to cool the building; or partially convected into the atmosphere increasing the ambient air temperature in the surrounding environment (Heat Island effect). The measure of reflectivity is the Solar Reflectance Index (SRI) which takes into account the properties of the material as well as the cooling effect of wind passing over the roof. The SRI for a low slope roof will be 0 for standard black (reflectance 0.05, emittance 0.90) and 100 for standard white (reflectance 0.80, emittance 0.90).

Architects and Specification Writers are increasingly selecting unpainted metallic coated steels for architectural roofing and cladding applications on building exteriors where they want a “Silver” metallic finish. This is occurring more frequently, and even on “prestige” type projects. The Canadian Sheet Steel Building Institute whose fabricator members manufacture a wide variety of building panel profiles for roofing and cladding applications, are being asked to supply unpainted (natural finish) galvanized or resin coated 55% Aluminum-Zinc coated steel for these architecturally exposed end uses. Oftentimes, these materials are specified because the designer finds the natural finish of these products very appealing and sometimes because of material cost savings opportunities. This Fact Sheet has been developed to provide guidance in material selection and provide information on the Architectural Metallic Finishes that are available for highly visible steep slope roofing and cladding applications.