Water-filled Glass


Water-filled Glass (WFG) is more than just a better glass unit. 
WFG redefines the way glass envelopes operate. 


Wfg requires no tinting, giving it a clear transparent look, while saving energy: 47-72% compared to double and 34-61% to triple glass .


The water layer can be tempered, minimizing risk of thermal discomfort and condensation.

glass & SOLAR collector

Wfg uses water to absorb energy, which flows to the mechanical system, making the window an effective solar collector.

Learn more about our story.

Quick introduction to WFG, including its operation and advantages.

Click to learn more about WFGs advantages for different building types:

- Conservatories, Sunrooms, Glass extensions:

WFG is a real asset for such projects, because of their high proportion of glass and typically south orientation: WFG improves thermal comfort (more daylight and view because less need for shading), energy consumption and works as a solar water heater: it captures heat that can be used elsewhere in the house (e.g. for heating or hot water), which saves energy for the home even if the room itself is not used.

The construction of large glass surfaces with water panels multiplies the efficiency of the WFG technology for these types of buildings, so their use is highly recommended

- Garden rooms/cabins:

WFG is a highly recommended system where the  buildings are small and prone to cool down fast (in winter) or overheat (in summer). This challenge makes WFG a real asset because it has a high thermal mass and has higher impact in smaller spaces. In addition to energy savings and comfort (more daylight and view with less shading), the solar water heater function of WFG operates here as well, which benefits the main building even when the garden room itself is not used.

- Building renovations, energy retrofits:

WFG is an ideal solution for energy retrofits of existing buildings as it improves thermal comfort, energy consumption and acoustics. Replacing the existing facade with WFG can be especially beneficial for buildings with dark glazing, where WFG enables significant energy savings with a clearer glass, which has a positive aesthetic impact, provides better views, more daylight and productivity in the building. 

- New construction, energy-efficient buildings:

Applied on new buildings, WFG technology has significant advantages over other glass technologies in terms of energy efficiency, increased comfort and acoustics, which leads to significant reduction in carbon emissions for the project and contribute significantly to achieve energy and climate goals. Using WFG results in more daylight and view (less need for shading), which improves productivity and makes WFG a perfect solution for high standard commercial (e.g. office, hotel) or residential buildings. Use of WFG also lowers peak loads in heating-cooling, which results in savings in construction cost in HVAC, leading to an attractive payback of WFG in this scenario. 

Buildings using WFG around the world.

The video offers a short introduction to WFG technology, with images from our latest project.
Our 'Water-Filled Glass' playlist on YouTube includes additional videos on WFG, which is updated with new materials regularly.

List and links of WFG publications in scientific journals and in the media.

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