The Project VAMOS addresses the retrofit of casement window with vacuum glass. Thereby, the project will examine for different types of casement windows (The “old Viennese casement window” / “Grazer casement window”, “the Viennese casement window”, etc.) and different levels of retrofit intervention (from “cosmetic” minimal-invasive refurbishment actions to total reconstruction / new construction of the corresponding casement windows) viable retrofit approaches regarding the integration of vacuum glazing. Methodologically, retrofit construction scenarios will be designed, tested and evaluated regarding their impact and performance both physically (laboratory) and virtually (numeric simulation), built and integrated in existing building envelopes. Subsequently, the described technology demonstrators will be subjected to a rigorous monitoring. Aspects that will be monitored encompass local and surface temperatures, condensation risk / relative humidity, air movement/velocities, and other objective and subjective performance indicators. The project will host the first realizations of casement window retrofit with vacuum glazing in (partly historically meaningful) existing buildings.
Generally, Vacuum glazing is considered as two-shell glass construction, with an evacuated interstitial space in-between. These glazing products have a very good thermal performance (UG-Values of 0.4 – 0.6 W.m-2.K-1), majorly due to the widely elimination of conduction and convection in the interstitial space. As such, these products require special consideration of their properties in window construction. In a previous project – VIG-SYS-RENO – it could be proved that these glazing products can generally be utilized for casement window retrofit, however, no realization was performed until now.
Based on the findings of VIG-SYS-RENO (and the two other projects involving vacuum-glazing products, MOTIVE and the ongoing FIVA-project) casement window designs encompassing vacuum glass will be first envisioned and designed, and then subjected to rigorous testing via empirical/physical and simulation-based models. Based on these efforts, decisions regarding the best construction method for each type of casement window and each degree of intervention will be taken. Questions, such as the positioning of the vacuum glazing in inner, outer or both shells of the casement window construction will thus be answered. The frame-geometries, joint details, and construction specifics will be highlighted and documented.
Both the demonstration site buildings’ inner spaces, affected by the retrofit, as well as the windows will be subjected to a rigorous monitoring. This will already start prior to retrofit to obtain comparison data for a before/after analysis. After retrofit the monitoring efforts will be continued. Thus, the effect of the vacuum glazing can and will be studied in detail, and evaluated regarding indicators such as the thermal comfort, the heating demand, and others.
One further focus is the documentation and authorship of a guideline pertaining to the application of vacuum glazing products in windows within sensitive building stock.
Expected results include not only improved thermal performances of the demo site buildings, but based on the demonstration sites an increased stock of documented experiences and knowledge regarding the specific aspects of retrofit projects encompassing vacuum glazing.
