Chuanya Roof Tile, which is specialized in the production of FRP Lighting Tiles,
The FRP lighting Sheets with a durability of 5-30 years use alkali-free glass fiber, reinforced polyester resin, high-performance anti-aging film, and additives.
It has the advantages of smooth appearance, lightweight and high strength, high light transmittance, corrosion resistance, aging resistance, and easy installation.
Common scenes include: the lighting of animal and plant greenhouses, industrial plants and civil building roofs, wall lighting, etc.
Its commonly used widths are dozens of models such as 840mm, 900mm, and 980mm, and the thickness is 1.0mm, 1.5mm, 2.0mm, 2.5mm, and 3.0mm.
Its light transmittance: is 70%-80%, and customized color tiles can be customized to be opaque.
Due to its excellent anti-corrosion performance, FRP is also widely used in highly corrosive roofs such as farms and chemical plants, so it is also called anti-corrosion tiles.
Due to its excellent plasticity, it has multiple models and sizes such as wavy, high-wavy, corrugated, and flat.
Square Meter Calculation
Shippment Reference,
20’ container
Total ** G, ** M, packed as two piles in one container, for reference only
40’ container,
Total ** G, ** M, packed as two piles in one container, for reference only
from NINGBO to DUBAI, UPDATE WEEKLY BY NINGBO *** SHIPPING LLC
For more port freight rates, please get in touch with us + Container and product deconstruction diagrams, rulers, port-to-port maps
Daylighting Roof Tile -- > Transparent Roof Tile made by Hangzhou Chuanya Building Material Co., Ltd
View Item Data
Model |
MY820/ MY840/ MY-760Fold Corner/ MY-820Fold Corner/ MY-470/ MY-750/ MY-820Corrugated/ MY-950/ MY-980/ MY-1025/ MY-980High Wave/ MY-820Cover/ MY-900/ MY-840Fold Corner/ MY-970/ MY-860/ MY-1050/ MY-750 |
Material |
Unsaturated Polyester Resin/ UV resistant film/ Fiberglass Roving |
Weight |
1.5KG/MM Standard, 1.1KG/MM Non-standard |
Color |
Transparent/ Grey/ White/ Blue/ Yellow |
Thickness |
0.8 - 3.0MM |
Usage |
Rooftop lighting and insulation/ External Wall/ Fence & etc. |
Width |
0.84 - 0.98 M |
Length |
840 type Corrugated Distance 210MM, height 25MM 980 type Corrugated Distance 245MM, height 35MM Customized Available, stock 6M |
FRP Lighting Tiles are a type of skylight material made of fiberglass reinforced plastic (FRP).
It is also known as fiberglass or transparent tiles, anti-corrosion tiles, and sunshine tiles.
This material has excellent temperature resistance and can work stably in a temperature range of -40℃ - 120℃.
Due to its unique properties, FRP Lighting Tiles have been widely used in many fields such as industrial plants, large markets, municipal projects, commercial facilities, and greenhouses for flowers and vegetables, providing a variety of bright lighting options for buildings.
Exquisite production technology of FRP Lighting Tiles, In the production process of FRP FRP Lighting Tiles, we selected the most advanced full set of production equipment in the industry provided by Boao Group,
with a total length of up to 65 meters,
far exceeding the old equipment used by existing manufacturers,
which is only about 40 meters long. It has 4 production lines, 3 factories 25 warehouses nationwide, and 120 cooperative dealers.
This advanced production process not only ensures the high quality and high performance of Lighting Tiles but also makes them unique in the market.
Daylighting Roof Tile -- > Transparent Roof Tile made by Hangzhou Chuanya Building Material Co., Ltd
Color Reference
FRP Lighting Sheets, Chuanya Roof Tile
![]() |
![]() |
![]() |
![]() |
FRP Lighting Sheets multiple colors, CHuanya Roof Tile | FRP Lighting Sheets multiple color with green, CHuanya Roof Tile | FRP Lighting Sheets multiple color with white, CHuanya Roof Tile | FRP Lighting Sheets multiple color with grey, CHuanya Roof Tile |
FRP Lighting Sheets, Roof Tile with leading production technology and equipment. ment, set research and development, production and sales of modern enterprises
Daylighting Roof Tile -- > Transparent Roof Tile made by Hangzhou Chuanya Building Material Co., Ltd
FRP Lighting Sheets, Chuanya Roof Tile
![]() |
![]() |
![]() |
![]() |
FRP Lighting Sheets in multiple colors with transparent, CHuanya Roof Tile | FRP Lighting Sheets multiple color with blue, CHuanya Roof Tile | FRP Lighting Sheets multiple color with red, CHuanya Roof Tile | FRP Lighting Sheets multiple color with black, CHuanya Roof Tile |
FRP Lighting Sheets, Roof Tile with leading production technology and equipment. ment, set research and development, production and sales of modern enterprises
Daylighting Roof Tile -- > Transparent Roof Tile made by Hangzhou Chuanya Building Material Co., Ltd
Details Displaying
![]() |
Panel Classification for FRP Lighting Sheets, Chuanya Roof Tile |
Classification of FRP Lighting Sheets(Chuanya Roof Tiles):
FRP FRP Lighting Sheets should be composed of high-performance upper film, reinforced polyester, and glass fiber.
The upper film should play a good role in anti-ultraviolet and anti-static. Anti-ultraviolet is to protect the polyester of FRP Lighting Panels from yellowing and aging, and premature loss of light transmission properties.
Anti-static ensures that the dust on the surface is easily washed away by rain or wind, maintaining a clean and beautiful surface.
Common models are:
400 Type/ 470 Type/ 666 Type/ 750 Type/ 760 Type/ 475 Type/ 478 Type/ 840 Type/ 820 Type/ 860 Type/ 900 Type/ 950 Type/ 960 Type/ 980 Type/ 1000 Type/ 1050 Type/ 1070 Type/ 1230 Type/ 1260 Type/ 1350 Type/ 1200 Type/ 1500 Type
Daylighting Roof Tile -- > Transparent Roof Tile made by Hangzhou Chuanya Building Material Co., Ltd
![]() |
Light Transmittance of FRP Lighting Sheets, Chuanya Roof Tile |
Features of lighting tiles:
1. Maintain stable performance within the temperature range of -40℃ to 120℃, without high-temperature softening and high cold embrittlement; it can also be designed into a double-layer structure with better thermal insulation effect, especially suitable for winter production in farms in the northern cold regions.
Daylighting Roof Tile -- > Transparent Roof Tile made by Hangzhou Chuanya Building Material Co., Ltd
![]() |
FRP Lighting Sheets not easy to corrode or oxidize, Chuanya Roof Tile |
2. Anti-shattering, super impact resistance, can block the impact of wind, snow, and hail, and avoid cracking and leakage of nail holes. 3. Easy to clean, easy to clean, no special care required.
Daylighting Roof Tile -- > Transparent Roof Tile made by Hangzhou Chuanya Building Material Co., Ltd
![]() |
High Temperature Resistance for FRP Lighting Sheets, Chuanya Roof Tile |
4. The lighting light is diffuse, the light is soft, the light transmittance is high, and it can effectively block most ultraviolet rays
5. When a fire occurs, the indoor smoke is discharged after rapid combustion, which can reduce casualties in the fire, and no molten droplets are produced during the combustion process, which can effectively protect the safety of on-site personnel
Daylighting Roof Tile -- > Transparent Roof Tile made by Hangzhou Chuanya Building Material Co., Ltd
![]() |
Good loadbearing for FRP Lighting Sheets, Chuanya Roof Tile |
6. It is corrosion-resistant, acid-resistant, and alkali-resistant, suitable for roofs of chemical workshops, such as fertilizer plants and electroplating plants
Daylighting Roof Tile -- > Transparent Roof Tile made by Hangzhou Chuanya Building Material Co., Ltd
![]() |
Case displaying of FRP Lighting Sheets for usage, Chuanya Roof Tile |
Usage of the FRP Lighting Sheets:
Industrial factory roof and wall lighting, agricultural vegetable greenhouse insulation lighting, public sports stadium roof lighting, special requirements of flame retardant, anti-corrosion and heat insulation of buildings, as well as warehouses, greenhouses, stations, docks, airports, commercial buildings, steel structures and many other lighting fields.
Daylighting Roof Tile -- > Transparent Roof Tile made by Hangzhou Chuanya Building Material Co., Ltd
![]() |
Production Displaying for FRP Lighting Sheets, Chuanya Roof Tile |
FRP skylight tile is a kind of skylight material made of fiberglass reinforced plastic (FRP for short).
Its main components include unsaturated polyester resin and glass fiber and its products (such as glass cloth, tape, felt, yarn), which are made through a continuous production process.
Daylighting Roof Tile -- > Transparent Roof Tile made by Hangzhou Chuanya Building Material Co., Ltd
Diagram View
![]() |
Diagram of FRP Lighting Sheets, Chuanya Roof Tile |
FRP Lighting Sheet is a kind of building material, and its nicknames include transparent tile, daylighting board, skylight strip, skylight roof, and Skylight Panel.
It is mainly divided into FRP fiberglass daylighting sheet, PC polycarbonate skylight tile, PET skylight tile, and UPVC skylight tile.
Among them, FRP skylight tile is widely used in China because of its advantages of corrosion resistance, aging resistance, impact resistance, low cost, energy saving and environmental protection, good light transmittance, flame retardancy, long-lasting performance, and rich colors;
while PC skylight tile is characterized by its beautiful appearance and high light transmittance (up to 85%).
Daylighting Roof Tile -- > Transparent Roof Tile made by Hangzhou Chuanya Building Material Co., Ltd
Installation
|
|
|
The FRP Lighting Sheets used for Atrium, Chuanya Roof Tiles | The FRP Lighting Sheets used for rooftop cover, Chuanya Roof Tiles | The FRP Lighting Sheets used for rooftop cover, Chuanya Roof Tiles |
Daylighting Roof Tile -- > Transparent Roof Tile made by Hangzhou Chuanya Building Material Co., Ltd
Before fixing the FRP Lighting Sheet, a pilot hole must be made. The hole diameter must be larger than 50% of the diameter of the fixing screw to avoid the internal stress caused by thermal expansion and contraction from cracking the skylight tile.
2. The FRP Lighting Sheet is fixed with aluminum profile fasteners, and the corrugated skylight tile is fixed with a skylight tile bracket and self-tapping screws, and then sealed with glue. The location of the skylight tile is generally set in the middle of the span.
3. When the FRP Lighting Sheet and the steel plate are overlapped longitudinally, there must be a minimum overlap of 200mm, and two water stops must be attached.
4. The FRP Lighting Sheet is connected with the self-tapping screws and must have a cover plate. The sun panel has large deformation due to hot and cold and is easily cut by self-tapping screws. Therefore, a larger hole should be opened at the self-tapping screw point of the sun panel. The elasticity of the FRP Lighting Sheet should be considered when installing the skylight panel.
5. When fixing the FRP Lighting Sheet, a good flashing gasket must be used to place it between the screw and the FRP Lighting Sheet to facilitate waterproofing and dustproofing. After inserting the flashing gasket into the screw, use an electric drill to lock it into the purlin to complete the fixing of the skylight board.
6. The FRP Lighting Sheet do not need to be overlapped within 12m, but overlap is required if it exceeds 12m. The overlap length is 200-400mm. Apply two layers of sealant at the overlap. The horizontal overlap does not need to be trimmed. The overlap of the longitudinal color steel plate depends on the plate type.
Ordinary corrugated steel plates are generally not considered to be trimmed. They are directly fixed to the color plate with self-tapping screws and sealed with sealant. The bite plate needs to be trimmed.
7. When constructing FRP Lighting Sheet, it is strictly forbidden to step directly on the crest to avoid cracking of the FRP Lighting Sheet.
A 1200mmx300mm (length x width) non-slip thick wooden board must be placed in the horizontal position of the FRP Lighting Sheet, and the foot must be stepped on it to make the guide holes and fix the screws of the FRP Lighting Sheet.
Hangzhou Chuanya Building Materials Co., Ltd, produced FRP Lighting Sheet. Mainly is made of fiberglass, UV Film with excellent anti-corrosion performance, and unsaturated Polyester Resin as the adhesive.
After molding, cooling, re-extrusion and other processes, high-quality FRP skylights are produced.
High light transmittance and UV resistance: The light of FRP skylight tiles is presented in the form of diffuse light, which is soft and not dazzling. At the same time, it maintains high light transmittance, which can effectively block most ultraviolet rays and ensure safe use.
|
|
|
|
FRP Lighting Sheets After mold shaping, Chuanya Roof Tiles | FRP Lighting Sheets through Roller Shaping, Chuanya Roof Tiles | FRP Lighting Sheets in Cutting Against Customized, Chuanya Roof Tiles | FRP Lighting Sheets change UV Film Roil, Chuanya Roof Tiles |
![]() |
![]() |
![]() |
![]() |
Shipment for FRP Lighting Sheets, Chuanya Roof Tile | Transparent Type of FRP Lighting Sheets in stock, Chuanya Roof Tile | FRP Lighting Sheets with black in Production, Chuanya Roof Tile | Transparent Type of FRP Lighting Sheets in Production, Chuanya Roof Tile |
Product Performance of FRP Lighting Sheet,
FRP skylight tiles are not only of various types, but each type has a unique performance.
For example, transparent FRP skylight tiles have excellent light transmittance and can meet high requirements for light; while UV-resistant ones can effectively resist the erosion of ultraviolet rays and ensure durability for long-term use.
In addition, heat-insulating FRP skylight tiles perform well in heat preservation and provide effective energy-saving solutions for various types of buildings.
At the same time, the emergence of colored FRP skylight tiles provides designers with a rich variety of color options to meet different aesthetic needs.
Daylighting Roof Tile -- > Transparent Roof Tile made by Hangzhou Chuanya Building Material Co., Ltd
Shipment
Hangzhou Chuanya Building Materials Co., Ltd, produced FRP Lighting Sheet.
Mainly is made of fiberglass, UV Film with excellent anti-corrosion performance and unsaturated Polyester Resin as the adhesive.
After molding, cooling, re-extrusion and other processes, high-quality FRP skylights are produced.
High light transmittance and UV resistance: The light of FRP skylight tiles is presented in the form of diffuse light, which is soft and not dazzling. At the same time, it maintains high light transmittance, which can effectively block most ultraviolet rays and ensure safe use.
Daylighting Roof Tile -- > Transparent Roof Tile made by Hangzhou Chuanya Building Material Co., Ltd
|
|
|
|
FRP Lighting Sheets manufacturer wholesale, Chuanya Roof Tiles | FRP Lighting Sheets through Roller Shaping, Chuanya Roof Tiles | FRP Lighting Sheets with transparent shipped on a truck, Chuanya Roof Tiles | FRP Lighting Sheets factory dellivery directly, Chuanya Roof Tiles |
![]() |
![]() |
![]() |
Screw of FRP Lighting Sheets, Chuanya Roof Tile | Screw of FRP Lighting Sheets 2, Chuanya Roof Tile | Accessory of FRP Lighting Sheets Rige Tile, Chuanya Roof Tile |
Strong impact resistance:
The FRP Lighting Tile has excellent impact resistance, whether it is wind, snow or hail, it can easily resist it, avoiding problems such as nail hole expansion and leakage caused by impact.
Wide temperature adaptability:
In the temperature range of -40℃ to 120℃, FRP Lighting Tile can maintain stable performance without high temperature softening or low temperature brittleness.
In addition, its double-layer structure design further optimizes the thermal insulation performance, which is particularly suitable for winter production in the northern cold regions.
Strong flame retardancy:
In the event of a fire, the FRP Lighting Tile can quickly burn and exhaust indoor smoke to reduce casualties. No molten droplets are produced during its combustion process, effectively protecting the safety of on-site personnel.
Superior corrosion resistance:
FRP Lighting Tiles have excellent corrosion resistance and acid and alkali resistance, and are very suitable for roofing in chemical workshops, such as chemical plants, electroplating plants and other environments.
Daylighting Roof Tile -- > Transparent Roof Tile made by Hangzhou Chuanya Building Material Co., Ltd
![]() |
![]() |
![]() |
![]() |
![]() |
![]() |
FRP Lighting Sheets Used for Ceiling, Chuanya Roof Tile | FRP Lighting Sheets Used for External Wall, Chuanya Roof Tile | FRP Lighting Sheets Used for Stadium Canopy, Chuanya Roof Tile | FRP Lighting Sheets Used for Breeding Shed, Chuanya Roof Tile | FRP Lighting Sheets Used for Simple warehouse rooftop, Chuanya Roof Tile | FRP Lighting Sheets Used for Horse Farm, Chuanya Roof Tile |
|
|
FRP Lighting Sheets Used for Plantation Roof, Chuanya Roof Tile | Usage Case of FRP Lighting Sheets, Chuanya Roof Tile |
![]() |
![]() |
![]() |
750 Type Transparent for FRP Lighting Sheets, Chuanya Roof Tile | 470 Type Transparent Covered Button for FRP Lighting Sheets, Chuanya Roof Tile | 470 Type Metal Hemming for FRP Lighting Sheets, Chuanya Roof Tile |
![]() |
![]() |
![]() |
820 Type Metal Hemming for FRP Lighting Sheets, Chuanya Roof Tile | 760 Type Metal Hemming for FRP Lighting Sheets, Chuanya Roof Tile | 820 Type Transparent Covered Button for FRP Lighting Sheets, Chuanya Roof Tile |
![]() |
![]() |
![]() |
940 Type Metal Hemming for FRP Lighting Sheets, Chuanya Roof Tile | 840 Type Transparent for FRP Lighting Sheets, Chuanya Roof Tile | 900 Type Transparent for FRP Lighting Sheets, Chuanya Roof Tile |
In terms of quality control of FRP skylight tiles, Hangzhou Chuanya Building Materials Co., Ltd. has taken a series of comprehensive and meticulous measures to ensure that every FRP daylighting tile shipped meets or exceeds industry standards and provides customers with durable building materials. The following is a detailed description of these measures:
1. Raw material selection and supplier management
The company strictly controls the selection of raw materials and only uses high-quality resins, curing agents, reinforcing fibers and other raw materials that have been strictly screened. These raw materials are all from certified suppliers with stable performance and reliable quality. By establishing long-term cooperative relationships with suppliers, the company can ensure a stable supply of raw materials and continuous stability of quality.
2. Production process control
During the production process, the company strictly follows the scientific production process, including the proportioning, mixing, molding, curing and other links of raw materials. In the proportioning stage, the company uses an advanced proportioning system to ensure that the proportions of raw materials such as resins, curing agents and reinforcing fibers are accurate and correct. In the mixing stage, high-efficiency mixing equipment is used to ensure that the raw materials are mixed evenly and free of impurities. In the molding stage, through fine mold design and precise molding process, the size and shape of the skylight tiles meet the design requirements. In the curing stage, the curing time and temperature are strictly controlled to ensure that the skylight tiles are fully cured and achieve the best performance.
3. Quality inspection and testing
The company has established a complete quality inspection system and conducts strict quality inspection and testing on each batch of FRP lighting tiles. These inspections and tests include appearance inspection, size measurement, light transmittance test, weather resistance test, heat resistance test and other aspects. The appearance inspection mainly checks whether the color, gloss, flatness, etc. of the skylight roof tiles meet the requirements; the size measurement ensures that the size of the skylight tiles is accurate; the light transmittance test evaluates the light transmittance of the skylight tiles; the weather resistance test simulates long-term exposure in the natural environment to test the anti-aging performance of the FRP daylighting panels; the heat resistance test evaluates the stability of the skylight tiles in high temperature environments. Through these inspections and tests, the company can ensure that every corrugated fiberglass roof panel shipped meets or exceeds industry standards.
4. Finished product storage and transportation
During the storage and transportation of finished products, the company has also taken a series of measures to ensure that the quality of the skylight tiles is not affected. The finished skylight roof tiles are stored in a dry, ventilated, light-proof warehouse to prevent moisture, discoloration or damage. During transportation, professional packaging materials and transportation tools are used to ensure that the FRP roof panels are not affected by external forces such as extrusion, collision or vibration during transportation.
5. After-sales service and continuous improvement
The company pays attention to after-sales service and continuous improvement to provide customers with all-round support. If customers encounter any problems or need technical support during use, the company will be able to respond in time and provide solutions. At the same time, the company also regularly collects customer feedback and market information, and continuously improves and optimizes products and production processes to continuously improve product quality and customer satisfaction.
Hangzhou Chuanya Building Materials Co., Ltd. has taken comprehensive and meticulous measures in the quality control of FRP lighting tiles, strictly controlling every link from raw material selection, production process control, quality inspection and testing, finished product storage and transportation to after-sales service and continuous improvement. These measures ensure that every FRP daylighting roof tile shipped out of the factory meets or exceeds industry standards, providing customers with long-lasting and durable building materials products.
As a professional FRP Lighting Tile and FRP Daylighting Panels manufacturer, Chuanya has all your roofing needs covered.
The antique integrated tile (PP resin) with a durable life of 3-15 years is a kind of artificial tile made of polypropylene resin as raw material, and it is formed by die stamping. The product feature...
See DetailsPP Chinese wall tile with a durable life of 3-15 years, commonly used thickness of 2.0-3.0mm, is mainly produced by polypropylene resin raw materials, through mold stamping. Compared with pvc resin wa...
See DetailsDurable life of 5-30 years as a synthetic resin tile commonly used width 1050mm type practical width 960mm and 880mm type practical 800mm, length pitch 220mm each section support customization, thickn...
See Details5-30 years of durability UV-PVC tiles are mainly made of Polyvinyl chloride (pvc) resin, anti-ultraviolet agent UV-P, antioxidants, and flame retardants as raw materials. Because its cross section is ...
See DetailsColor Steel Tiles, also known as colored corrugated tiles, are corrugated sheets made of colored coated steel plates rolled and cold-bent into various corrugated shapes. It is suitable for industrial ...
See DetailsChuanya Roof Tile, which is specialized in the production of FRP Lighting Tiles, The FRP lighting Sheets with a durability of 5-30 years use alkali-free glass fiber, reinforced polyester resin, high-p...
See DetailsChuanya Roof Tile, which is specialized in the production of PC Endurance Panel/ polycarbonate solid sheet, PC Endurance Panel with a durability of 5-15 years is also called polycarbonate sheet. The ...
See DetailsThe antique integrated tile (PP resin) with a durable life of 3-15 years is a kind of artificial tile made of polypropylene resin as raw material, and it is formed by die stamping. The product feature...
See DetailsPP Chinese wall tile with a durable life of 3-15 years, commonly used thickness of 2.0-3.0mm, is mainly produced by polypropylene resin raw materials, through mold stamping. Compared with pvc resin wa...
See DetailsDurable life of 5-30 years as a synthetic resin tile commonly used width 1050mm type practical width 960mm and 880mm type practical 800mm, length pitch 220mm each section support customization, thickn...
See Details5-30 years of durability UV-PVC tiles are mainly made of Polyvinyl chloride (pvc) resin, anti-ultraviolet agent UV-P, antioxidants, and flame retardants as raw materials. Because its cross section is ...
See DetailsColor Steel Tiles, also known as colored corrugated tiles, are corrugated sheets made of colored coated steel plates rolled and cold-bent into various corrugated shapes. It is suitable for industrial ...
See DetailsChuanya Roof Tile, which is specialized in the production of FRP Lighting Tiles, The FRP lighting Sheets with a durability of 5-30 years use alkali-free glass fiber, reinforced polyester resin, high-p...
See DetailsChuanya Roof Tile, which is specialized in the production of PC Endurance Panel/ polycarbonate solid sheet, PC Endurance Panel with a durability of 5-15 years is also called polycarbonate sheet. The ...
See DetailsThe antique integrated tile (PP resin) with a durable life of 3-15 years is a kind of artificial tile made of polypropylene resin as raw material, and it is formed by die stamping. The product feature...
See DetailsPP Chinese wall tile with a durable life of 3-15 years, commonly used thickness of 2.0-3.0mm, is mainly produced by polypropylene resin raw materials, through mold stamping. Compared with pvc resin wa...
See DetailsHangzhou Chuanya Building Materials Co., Ltd. is a one-stop factory for building material
Learn MoreTerry Q. postmaster@hangzhoucy.cn
Huryson Daniel Daniel0012@hangzhoucy.cn
Ota Wudy Ota0016@hangzhoucy.cn
Sara Pryson sara@hangzhoucy.cn
Adam Alen adam@hangzhoucy.cn
Terry Q. +86 188 1484 7738
Huryson Daniel +86 181 4347 3370
Ota Wudy +86 157 5865 0762
Sara Pryson +86 133 2573 7508
Adam Alen +86 173 7033 3356
No. 1, Hongqi Village Industrial Park, Xucun Town, Haining City, Jiaxing City, Zhejiang Province, China
Copyright © Hangzhou Chuanya Building Materials Co., Ltd. All Rights Reserved. Wholesale Corrugated Fiberglass Roof Panels Suppliers