A report on the best roofing materials for Indian climate.

A roof provides protection and shelter to be safe from sunlight, rains, winds etc. Roof are the most essential requirement in a project considering the various parameter such as durability, sustainability, better life cycle, and low maintenance cost are expected from a selected roof. Manish Asawa, Managing Director, Asawa Insulation Pvt Ltd, says, “No roof will fulfil the requirement as desired since in India due to shifting climatic conditions. The best way to reduce the ambient temperature is by insulating the roof (Underdeck Application) from below to prevent heat transfer through the roof.”

Modern roofing options
Climate of India comprises of a wide range of weather conditions across topographies. However, it could be generalised that most part of the country experiences tropical conditions. Choosing the right roofing material for a given structure set in a tropical backdrop, is an important aspect while designing the overall architecture. Mahendra Pingle, Dy. General Manager – Market Development – Tata BlueScope Steel Ltd, says, “Roofing innovations in recent times have addressed issues raised by conventional materials such as asbestos sheets, cement sheets, clay tiles and thatched roofs. Due to various factors such as speed of installation, labour intensive work, durability of the roofing material, design flexibility, overall maintenance and thermal efficiency, architects now prefer corrosion resistance metallic coated (Zincalume steel) or colour coated (COLORBOND steel) metal roofing in place of conventional roofing materials .”
Due to longevity, aesthetics and high solar reflectivity requirements for buildings such as manufacturing facility, railways, metro stations, power plants, aviation’s, sports and warehousing or distribution centre, colour coated metal roofing is preferred by private and government institutes. He opines, “Moreover, colour coated metal roofs (with THEMRATECH technology) offer better insulation on the exterior, reducing the overall energy consumption and are also environmentally friendly (lead free) as they are recyclable. Expert installation facility with very low or no maintenance has enabled coated steel roof as the preferred choice.”

Must be eco-friendly
According to Rajiv Gupta, CEO, Eview Global Pvt Ltd, Roofing material must be seen based on extreme Indian climatic conditions like extreme heat and cold, excessive rain, corrosive environment as plant being near to sea etc. He adds, “The physical conditions of the shed from within must also be considered like fumes from different operations inside the shed. The industry requirement of strength of the roof to be able to accommodate later additions to roof top like roof top solar or daylighting or wind driven turbine etc.”

Accordingly to Eview the most important factor that must be considered by the industry is the health of the environment. The roof must be eco-friendly and should take care of the extreme requirements.

Advanced roofing solutions:
SMART PIR (Polyisocyanurate) Panels
Asawa from Asawa Insulation, informs, “SMART PIR (Polyisocyanurate) Panels is used in Underdeck application (below the roof) to prevent heat transfer due to conduction, convention and radiation. Smart Panels because of it lowest thermal conductivity of 0.019 W/mk can reduce the surface temperature by 10° (with a 15mm thick panel) – 18° (30mm thick Panel). Smart Panels are a class O fire retardant product (Tested by CBRI Roorkee, Exova Warrignton and EN13403).

Smart PIR Panels are 97 per cent closed cell CFC and HCFC free sandwiched panels between either both side aluminium/ kraft paper/ combination of both based on the application of the project. Smart Panels does not allow water abruption or water transmission. For different project different product is used for Underdeck roof insulation.

He further adds, “For industrial application it can directly be placed below the roofing sheet covering the purling to purlin distance and can be screwed together with the corrugated sheets for permanent solution. We also have a special polymer profile that can be used between the sheets to avoid any heat leakages.”

Smart PIR Panel being a green building product is energy efficient as it helps in reducing the ambient temperature providing better thermal comforts. Smart Panels can be very well be used in commercial, residential and industrial applications.

LYSAGHT Product Range – Tata BlueScope Steel
Tata BlueScope Steel’s building products division offers LYSAGHT range of premium roof and wall cladding for industrial, infrastructure, commercial and residential segments. The division believes in continuous improvement to meet increasing customer needs. Pingle from Tata BlueScope, explains, “LYSAGHT offers innovative roofing in form of pierced fixed, concealed fixed and standing seam roofing system for superior architectural appeal and addresses the most demanding construction and design requirements while crafting roofs with outstanding performance and pleasing aesthetics. Moreover, the concealed fixed system KLIPLOK / FLEX-LOK helps provide weather tightness, allow thermal expansion and contraction, saving on steel under length overlaps (single length sheet from ridge to eave), fast installation and superior resistance to wind uplift, ideal for industrial and commercial applications.”

Company’s structural decking system “SMARTDEK” for multi-storey buildings ensures precision engineering with greater economy and design freedom. Pingle adds, “All our pierced fixed and concealed fixed profiles have specially designed ribs, with unique anti-capillary side lap, making it leak proof even up-toslope of 3+ degree (pierced fixed) and 2 deg. for concealed fixed.”
LYSAGHT roofs are equipped with advanced features that allow thermal contraction and expansion under varying temperatures, giving a leak proof performance. All LYSAGHT profiles are made from superior quality materials such as COLORBOND steel and ZINCALUME steel that offer higher solar reflectivity and lower thermal mass, thereby providing cool comfort for building occupants. This system lowers roof temperature by up to 6 degree Celsius and reduces electricity consumption by up to 15 per cent over conventional roofing system, thereby providing greater thermal comfort throughout the year while using less energy. Launched in 1966; COLORBOND steel was developed specifically in response to the harsh climatic and weather conditions, including extreme temperature and moisture variations, and intense ultra violet radiation. COLORBOND steel undergoes rigorous corrosion, durability and application test under actual conditions. Being durable, lightweight, long lasting and aesthetically pleasing; it is being used on all cladding forms including roofs and walls.

Eview’s Eco roof
Gupta from Eview, explains, “Eview offers Eco roof, corrugated roof made out of recycled and recyclable, polyethylene and aluminium. It has the strength of 99 kg per sq. inch and is 6 mm thick and comes with aluminium lamination on top, with an option of double side lamination. It can withstand fumes from operations in the shed. The temperature in the sheed is cooler as compared to metal sheds. It comes with a long life.”

Advantages of Eco Roof
• Water resistant
• Fire retardant
• Resistant to sulphuric acid (5 per cent w/w for 24 hrs)
• Resistant to alkali (2 per cent sodium carbonate for 24 hrs)
• Tensile strength of 99Kgs/sq.cm
• Resistant to salt spray (5 per cent NACL for 72 hrs)
• It is non toxic
• Thermal reflectivity
• Resistant to high temperature
• Recyclable.

Maxroof’s high end roofing solutions
Maxroof have established itself with its vast experience as one of the top most solution provider in metal building systems, by having its own manufacturing facility for extensive range of products like roofing, purlin, structural decking and complete range of accessories since its inception in year 2006. Sanjeev Rai, Founder and MD, MaxRoof Corporation Pvt Ltd, says, “We are into complete turnkey solutions for Pre-Engineered Metal Buildings (PEB) and roofing system to best suit the need for Industrial sheds, warehouses, residential roofs, commercial and infrastructure buildings.”

Maxroof being one of the experts in offering high end roofing solutions with its seamless, standing seam roofing systems. Its wide range of roofing and wall cladding materials, purlins, structural decking, accessories, gutter and down take pipe, louvers, ridge or turbo ventilators, polycarbonate sheets are made from high quality materials.
Rai explains some of the advanced solutions for roofing:
Trapezoidal roofing and wall cladding sheets
MxRIB
MxRib 1010 is one of the most in demand roofing and wall cladding profile as it serves two most important purposes, first strength and second Aesthetics and hence becomes architects first choice.

MxCrest
MxCrest 1000 is a profile with muscles. Large crest with two parallel mini ribs between the crest makes the profile stronger which translates into long spanning capabilities. Thus the profile is most recommended for heavy rainfall intensity area.

Mxline
Mxline 1050 is designed to provide an aesthetic and economical liner panel and wall cladding solution for exterior and interior use. Mxline has wide cover width of 1050 mm which maximise the efficiency. The small ribs in between the crest give additional strength to the profile and enhanced look.

Seamless roofing sheets
MxZiP
MxZiP is an innovative and technologically advanced concealed fixed and zipped-up standing seam system that creates a continuous weather tight roof. MxZiP offers outstanding design potential, performance and durability. MxZiP can be offered in profile width ranging from 300 mm to 500 mm. The standard profile width is 430 mm. MxZiP can also be offered in tapered or curved profile and it can be site roll formed.

MxloK
MxloK is advanced, wide cover, concealed fix roofing. The system is ideal for long spans on industrial, commercial and retail buildings.

Smart PIR Panel being a green building product is energy efficient as it helps in reducing the ambient temperature providing better thermal comforts.
Manish Asawa, Managing Director, Asawa Insulation Pvt Ltd

LYSAGHT roofs are equipped with advanced features that allow thermal contraction and expansion under varying temperatures.
Mahendra Pingle, Dy. General Manager – Market Development, Tata BlueScope Steel Ltd

Eview offers Eco roof, corrugated roof made out of recycled and recyclable, polyethylene and aluminium.
Rajiv Gupta, CEO, Eview Global Pvt Ltd

Maxroof being one of the experts in offering high end roofing solutions with its seamless, standing seam roofing systems.
Sanjeev Rai, Founder and MD, MaxRoof Corporation Pvt Ltd