This project incorporates a Semi Frameless Glass Box solution housing the office and sales departments of KAL Kitchens in Citywest. This semi frameless glass box solution has been made unique by the construction of a reflective glass clad skin. This rectangular form, 8m in height, 40m long and 14m wide runs at an dynamic angle to the composite clad rectangular warehouse, projecting and cantilevering over the main entrance and natural landscape area and extending deep into general serving and admin departments.

This distinctive form of semi frameless glass box façade solution has transformed the architectural intent into corporate identity, worthy of the products and services within.

The outer envelope of the semi frameless glass box solution is constructed from the Reynaers suite of stick curtain walling using a structurally clamped Reynaers solution with frameless casement sashes. The Module layout has been standardized to 1200mm widths with the external corners been fabricated to site dimensions.

All height and levels were agreed to ensure that external sightlines of the façade remained visually consistent with other forms and activities crossing its path.

The use of antilleo clear as a solar control glass has a number of distinct characteristics. Depending on external daylighting, it becomes highly reflective offering privacy to the internal activities whilst becoming a changing external active mirror to the external landscape.

The face glass of the Semi Frameless Glass Box is toggled; the external pane is fritted along its external perimeter enhancing the visual appearance of the insulated double glazing and offering protection to its seal against ultraviolet light.

All face joints are 20mm wide, pointed in Dow corning 791. The joints are flush, enhancing the rectangular form.

The detailing to the base and head parapet are fully integrated with an optimised visual site line of 20mm. Special attention has been given to each detail in respect of reducing the risk of thermal bridging and condensation. Site specific method statements were prepared to ensure that that on site workmanship achieved acceptable levels of air and water tightness.

The selection of a hard coated glass enabled the face glass to be fritted on face two as edge deletion was not required giving it a distinct advantage over the use of a soft coated glass. The application of a ceramic print to face two of the toggled unit adds value and product longevity. Its presence enhances by time extension the service life of the façade.

The use of antilleo clear was critical to the environmental strategy; its performance characteristics provided satisfactory daylight transmission, combated against excessive solar gain, however it required the use of a soft coated low e glass internally to ensure a low u value.

The reflectivity of the face glass required strict control of the toughening process and every step was taken to minimize roller wave distortion. All glass is toughened both externally and internally to minimise the risk of thermal fracture. All the glass is heat soak tested to reduce the risk of nickel sulphide inclusions.

The reflectivity of the Semi Frameless Glass Box solution was enhanced by balancing the external appearance of vision panel to spandrel area. This was achieved in two respects; firstly, the face glass remained the same in both situations and secondly the internal ral finish of the spandrel (ral 7037) was carefully selected to ensure visual consistency in all external lighting conditions.

Every endeavour has been made to improve the whole life cycle of this Semi Frameless Glass Box solution. Costs have been assessed on the basis of payback.

Our ethos is to balance architectural intent through intelligent academic and practical robust detailing. We understand construction risk.

Download information: Kal Kitchens Citywest