_El temple de la Sagrada Família_: a book published by Isidre Puig Boada, architect and disciple of Gaudí, in 1929, three years after the master's death, to record how the Basilica should be. In 1999, the artist Joan Vila-Grau began the process of creating the Basilica's stained glass windows, a project he dedicated over twenty years to. Vila-Grau, who above all considered himself a painter, used leaded glass, a technique different from trichromy, little developed by Gaudí. This allowed the architect's vision to be realised, taking into account the criteria of ventilation, durability, and complexity required by the project. Drawing showing the sun's trajectory throughout the day and the different seasons of the year in relation to the cardinal orientation of the Basilica's floor plan

When studying the Basilica and comparing it with the functioning of Gothic cathedrals, one can understand Gaudí's intention to surpass that style. Structurally, the architect managed to eliminate exterior elements, such as flying buttresses and buttresses, which he considered to be like crutches, thanks to the arboreal structure of the interior that helped to relieve loads. The stained-glass windows in the naves not only consider the daily solar trajectory but also how light changes throughout the seasons. The Earth's daily rotation on an axis tilted with respect to the planet's trajectory around the sun causes days to lengthen or shorten. This means that in the northern hemisphere, there are more daylight hours in summer, as the sun rises earlier from the east. Less in winter, because the sun sets before reaching the west. In this way, with light and colour, Gaudí explains the birth and death of Jesus and creates an atmosphere that invites **reflection and prayer.

The morning sun enters from the east, where the Nativity façade is located, marking the beginning of life. This is why the glass panels facing this part have cool, bluish tones, corresponding to the light of dawn. In contrast, the afternoon sun departs from the west, where the Passion façade is located, marking the twilight of the day and of life. Therefore, the glass panels facing this part have red and orange tones, like the light of dusk. The spectacle of colours inside the Basilica intensifies during two moments of the year thanks precisely to this solar trajectory and light exposure. In summer, as the sun rises earlier from the east, during the first hours of the morning, solar rays enter more directly through the stained-glass windows on the Nativity side, almost perpendicularly. In winter, however, as the sun sets before reaching the west, the rays penetrate straight through the stained-glass windows on the Passion side. See the following explanatory drawing: Photo of the Basilica's interior showing the difference between the lower stained-glass windows, full of colour. The white windows in the upper part.

The price for enamelling doors and windows in La Sagrada Família usually ranges between 133 and 1900 euros. The final figure depends on the condition of the property, the materials, and the time required. We always provide a fixed quote before starting work. Joan Vila-Grau (Barcelona, 1932-2022): an artist professionally dedicated to painting, ceramics, and stained glass. Interested in the renovation of liturgical art, he specialised in the historical study of Catalan stained glass and the creation of contemporary stained glass. Trichromy: A method consisting of superimposing four thicknesses of glass, one for each primary colour (yellow, cyan blue, and magenta) and white. With an acid, the colour intensity of each glass is reduced according to the desired shade. For example, if green is desired, red is softened, and yellow and blue remain intense. Of these two, yellow is reduced more if a darker green is wanted, or blue if a lighter green is desired.