High indoor temperature under the skylight, strong heat radiation, and the light irritates the eyes are common shortage of glass skylights,customers can increase the glass thermal insulation peformance and decrease glass SC to avoid the problem

1. QINGDAO MORN BUILDING MATERIALS CO.,LTD
Your turnkey China tempered glass/laminated glass/insulated glass supplier
Add:Room A304,Shengxifu Road,NO.209 Weihai Road,Shibei District,Qingdao,China,266024 MARKETING@CNMORN.COM
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Solutions to the greenhouse effect of glass skylight
Glass skylights are commonly used in modern buildings, but series problems happened when people
enjoying the direct sunlight through the glass,for example: the high indoor temperature under the skylight,
strong heat radiation, and the light irritates the eyes.This phenomenon of glass skylight is called
greenhouse effect.
What is the greenhouse effect?
Solar energy enters the room through the glass and cause the indoor temperature to rise, especially in
summer, and the heat entering the room is not easy to naturally radiate through the building, which makes
the indoor thermal comfort and light comfort deteriorates.
Even if the air temperature is suitable under the skylight, as long as there is sunlight, people still feel hot
and uncomfortable, just like people standing outdoors under the sun.

2. QINGDAO MORN BUILDING MATERIALS CO.,LTD
Your turnkey China tempered glass/laminated glass/insulated glass supplier
Add:Room A304,Shengxifu Road,NO.209 Weihai Road,Shibei District,Qingdao,China,266024 MARKETING@CNMORN.COM
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Under the same indoor air temperature,the temperature felt by the human body under the building with
ordinary windows and the skylight is very different,sometimes the overall air synthetic temperature under
skylight can be 15℃ higher than windows.
Factors cause greenhouse effect?

3. QINGDAO MORN BUILDING MATERIALS CO.,LTD
Your turnkey China tempered glass/laminated glass/insulated glass supplier
Add:Room A304,Shengxifu Road,NO.209 Weihai Road,Shibei District,Qingdao,China,266024 MARKETING@CNMORN.COM
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1. Solar shading coefficient:
The overall air synthetic temperature is directly proportional to the skylight solar shading coefficient.Better
solar shading coefficient improve the thermal environment under the roof, and increase thermal comfort. It also
helps reducing the cooling energy consumption in summer.
2. Solar radiation.
The overall air synthetic temperature is directly proportional to the solar radiation. In hot summer and cold
winter areas the greenhouse effect under the skylight is extremely significant, and measures must be taken to
solve it, otherwise the human body under the lighting roof feels overheated. In cold regions, there is also a
period of strong solar radiation in summer.
Measures to increase indoor comfort
1. Decrease skylight glass U value
Skylight glass are usually laminated insulated glass, laminated glass is inside to prevent glass fragments falls
once glass broken.
In our previous posts,the glass thermal insulation performance (Glass U value) is affected by the glass
installation angle,learn more:How the glass U value been affected by the installation angle?
Firstly,skylight designers and architect should be aware of below conclusion:
In summer condition,glass U value is not affected by the installation angle,from 0° to 90°.
In cold winter conditions,glass U value decrease from 0 ° to 90 ° ,take solarban 60 double silver low-E
coating as example,glass U value decrease from 1.66 to 2.47,which helps reduce air heating costs.

4. QINGDAO MORN BUILDING MATERIALS CO.,LTD
Your turnkey China tempered glass/laminated glass/insulated glass supplier
Add:Room A304,Shengxifu Road,NO.209 Weihai Road,Shibei District,Qingdao,China,266024 MARKETING@CNMORN.COM
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Measures to reduce glass U value:
A. Using high performance double silver low-E and triple silver low-E coatings.
B. Using argon filled insulated glass to replace the air inside glass.
C. Using warm edge spacer instead of traditional aluminium spacers to decrease glass edge thermal
insulation.
D. Change double glazed units to triple insulated glass.
More details can be found here:
Insulated glass-feature,thermal performance&calculation tool
Extend:
Argon filled insulating glass VS warm edge spacer insulating glass
2. Decrease glass Solar shading coefficient
Glass solar shading coefficient is related to the glass light transmittance,glass light reflectance,and the low e
coating types.
High performance double silver low-E coatings and triple silver low e coatings transfer the sunlight into cold
light,allow much less solar radiation through the glass.
Below tables shows the difference between single,double and triple silver low-E under same light
transmittance.

5. QINGDAO MORN BUILDING MATERIALS CO.,LTD
Your turnkey China tempered glass/laminated glass/insulated glass supplier
Add:Room A304,Shengxifu Road,NO.209 Weihai Road,Shibei District,Qingdao,China,266024 MARKETING@CNMORN.COM
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For cold areas,customers can use high performance triple silver low-E coating for skylights projects.
Glass manufacturers also developed the right low e coatings suitable for glass skylight projects in hot
areas.The features of this kind coating is medium light transmittance,high light reflectance and low solar
coefficient compared with other coatings.
Other methods to decrease glass solar coefficient including body tinted glass,colorful PVB
interlayer ,ceramic frit on glass surface,and even photovoltaic glass with opaque ceilings also works
to help decrease glass SC value.

6. QINGDAO MORN BUILDING MATERIALS CO.,LTD
Your turnkey China tempered glass/laminated glass/insulated glass supplier
Add:Room A304,Shengxifu Road,NO.209 Weihai Road,Shibei District,Qingdao,China,266024 MARKETING@CNMORN.COM
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3. Apply thermal insulation film on existing skylight projects
For already installed skylights,it’s impossible to change the existing glass combinations.Glass film is perfect
option for customers to decrease glass solar coefficient,below pictures shows a project installing solar
reflecting films ,after installation process,indoor temperature under the glass skylights decreased by 12-15
degree.

7. QINGDAO MORN BUILDING MATERIALS CO.,LTD
Your turnkey China tempered glass/laminated glass/insulated glass supplier
Add:Room A304,Shengxifu Road,NO.209 Weihai Road,Shibei District,Qingdao,China,266024 MARKETING@CNMORN.COM
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4. Adding extra interior or exterior solar shading facilities.
The glass skylights can add external or internal shading facilities,for example outdoor fabric canopy,FSS roller
awning,FCS awning,FTS awnings.Beside awnings, electrical aluminium louver systems also works to stop
light transmit glass directly.
The difference between internal shading and external shading system is：
External solar shading systems stop the direct solar radiation through the glass,the overall solar radiation
through glass was minimized,but for structural reason,external shading systems price is higher.
Internal solar shading systems cannot decrease the heat through glass,but as the shadings color is light,the far
radiation generated by the sunlight was decreased as well.

8. QINGDAO MORN BUILDING MATERIALS CO.,LTD
Your turnkey China tempered glass/laminated glass/insulated glass supplier
Add:Room A304,Shengxifu Road,NO.209 Weihai Road,Shibei District,Qingdao,China,266024 MARKETING@CNMORN.COM
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9. QINGDAO MORN BUILDING MATERIALS CO.,LTD
Your turnkey China tempered glass/laminated glass/insulated glass supplier
Add:Room A304,Shengxifu Road,NO.209 Weihai Road,Shibei District,Qingdao,China,266024 MARKETING@CNMORN.COM
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Both shading systems avoid the direct sunlight ,decrease the people apparent temperature.
Glass skylight brings light and sun energy into the room,architects and designers should take measures to
minimize the negative high temperature caused by the direct sunlight through glass,and shading systems.
China Morn can helps manufacturing and supplying the right insulated glass based on your skylight project
location,temperature and area,welcome contact us for your next skylight project.
Contact us:
Qingdao Morn Building Materials Co.,Ltd
China HQ: Room A304,Shengxifu Road,NO.209 Weihai Road,Shibei
District,Qingdao,China,266024
Sales Email: marketing@cnmorn.com
Technical support: han@cnmorn.com Mobile/Wechat: 0086-17705464660
Website:https://www.cnmorn.com/ https://www.mornglass.com/