With ever growing and fast technological changes taking place in construction of buildings, concept of making buildings is fast changing from conventional labour intensive progress to pre-fabricated and modular concept in making of buildings which are less time consuming and are environment friendly including better resistance towards frequent earthquakes.
Conventional RCC Chajjas are less durable, prone to cracks and difficult to maintain hence need to have durable and prefabricated chajjas which are light in weight and eas to install and maintain over its long period of use.
Why FRP Chajja?
FRP is a wonder composite material and is generally known for its very high strength, durability, resistance to high temperature and extremes of weathering, resistance to environmental corrossion and being light in weight, hence due to above inherent properties FRP prefabricated chajjas in one single piece are the most prefered and suitable material for the said application.
Ease of Installation
Prefabricated FRP Chajja in one single piece are light in weight hence easy to lift and fix at suitable height with minimum arrangements at site. Below details for installation will further define the ease of handling and installation of FRP Chajja at site.
1. For Installation of FRP Chajja basic scaffolding arrangement is made for lifting and placement of the same at the required height.
2. Each FRP Chajja which needs to be fixed has a flange to be inserted inside the slot and the same is made using marble cutting machine, 5-6mm wide, 25-50 mm depth, accordingly flange is insterted inside the slot. Holes are made as per provision given for anchoring of chajja with the help of hammer drill machine in required size and depth, depending on the length of Chajja.
3. Check for alignment of FRP Chajja and fasten the Chajja using grouting bolts as per size and defined load factors.
4. All the gaps are sealed using silicon sealant from top and bottom to make it water proof.
5. FRP Chajja as evident from the drawing is designed for easy handling, fixing, load bearing and maintainence.
Providing & fixing of factory made Fiberglass Reinforced Plastics (FRP) “CHAJJA”- 4mm thick of “Fibreways” brand or equivalent in required colour, size and design made by Resin Transfer Moulding (RTM) Machine Technology, resulting in void free compact laminate in single piece, having smooth gradual slope curvature for easy drainage of water and duly reinforced by 2 nos. vertically and 1 nos. horizontally 50x2mm thick M.S. Flat with 12mm in built hole for grouting on the existing wall along with the 50mm flanges duly inserted and sealed in the wall complete in one single piece casted monolithically including all necessary fittings. The FRP Chajja should be manufactured using unsaturated Polyester resin as per IS: 6746 duly reinforced with fiberglass chopped strand mat (CSM) as per IS: 11551 complete with protective Gelcoat U/V coating on Top for complete resistance from the extreme of temperature, weather & sunlight.
Material for Construction
1. Process of manufacturing: RTM Machine moulding technology – FRP Chajja to be made in one single pc. With no joints. (Monolithic casting).
2. Gelcoat with desired pigment for outer coating. (U/V Stabilized)
3. Unsaturated polyester resin as per IS-6746.
4. Glass fiber reinforcement: Chopped Strand Mat (CSM) as per IS – 11551.
5. The Glass fiber roving used shall be as per IS – 11320.
6. Curing Agents-MEKP & Cobalt Napthalate.
7. Permissible fillers are French chalk powder and shall not exceed 10% by weight of unsaturated polyester resin.
8. 2mm M.S. Plate reinforcement on the backside of the FRP Chajja to be inserted between the layers of FRP Laminate.
9. Flange arrangement to be provided in the FRP Chajja for grouting inside the existing wall to make it water proof.
10. Both side smooth glossy finish.
11. Tolerance of ± 10mm in overall size of FRP Chajja.
12. Thickness of FRP Chajja to be 4.0mm.
External protection to all windows, doors, openings, etc. in any housing, commercial, warehouses, residential buildings.
References: As per CPWD – DSR (2014), MES.
Advantages of FRP Chajja
• Advantageous strength/ weight ratio and rigidity.
• Moulding size virtually unlimited.
• Considerable design versatility.
• Choice of wide range of Inbuilt color-Maintenance free finishes.
• Easy to handle and install at site.
• Easy of repair and maintenance if any at site.
• Excellent water, chemical & termite resistance.
• Resistant to weathering and UV exposure (U/V stabilized).
• Fire retardant.
• Good electrical and thermal properties.
• Good aesthetic appeals, strength, durability, waterproof & lightweight.
• Good dimensional stability at high temperatures. (Unlike PVC or MS)
• Very high impact strength -used for body covers of high-speed cars etc.
• Excellent Thermal insulation.
• Excellent mechanical/physical & biological properties.