Peter Zumthor a well-known name famous for its play with material expressions, unusual techniques of construction. His work is representative for the framework of material and construction process. Along with these aspects his design highlights the program encompassing the materiality and the reality to full extent. Being a son of cabinet maker; thinking of smallest detail possible and implementing it in real scale is in his veins. His work makes a person lost in the space by experiencing its visual connection to the soul through physical, ephemeral quantities which he constantly refers as “Atmospheres”. (Zumthor, 1 March 2006) This paper explores and understands how materials, structure as well as details governs the visual and spatial experiences in his buildings and directly connects to the program and its functions. The analysis is based on the writings and my own interpretation through his built projects. In the outskirts of Wachendorf - a small village of Germany stands Bruder Klaus chapel. The farmers had to construct a chapel to honour their saint Bruder Klaus from 15th century. This one sentence became a program for Peter Zumthor which he made to landmark of Germany’s natural landscape. Figure 1 : The building acting as a landmark and as well as a memorial for the saint Bruder Klaus. The use of indigenous material and techniques of construction showing love and respect of the people to the saint Bruder Klaus. A strong rigid geometry from outside but a thought-provoking interiors changes and disorients you from the outside world. The natural indirect lighting from the top through a central access creates the distance in the exterior and interior. The unique undulated oculus resembles the star of saint Bruder Klaus. The resemblance is more emphasized by the construction and dealing the shuttering holes in a unique way by pouring molten glass and blowing it hence creating a stark effect of the stars in the universe with the flare of Bruder Klaus through top. Figure 2 : Section of the chapel showing the negative space (black) as the concrete and the (white) space forming a formwork of pine logs which are burnt after construction. The light from the oculus giving importance to the dark space. Figure 3 : The light from the oculus resembling as a flare of star of Bruder Klaus with the small shuttering holes filled with molten glass as stars in the universe. Figure 4 : The shuttering holes for the formwork where left transparent and filled with molten glass resembling stars in the universe. The building made with rammed concrete gives a sense of heavy mass from outside showing the importance of the saint and his birth place by using local materials and construction technique. In this way a simple program with fascinating spatial experience made its own way with the help of materials and construction. Moving a bit far from Germany towards south on the foothills of the mountain peak of Piz Serenastga one can see the baths of Therme Vals. “When I work on a design, I allow myself to be guided by images and moods that I remember and can relate to the kind of architecture I am looking for.” (Peter Zumthor, 1998, 25) Zumthor had a program brief to design a spa for a hotel 7132 in the year 1993. Zumthor started his design with basic history of baths dated back in the age of Romans. Hence the material – STONE is taken into consideration as if they were a form of cave and the grass on the roof structure resembling the archaeological site of the ancient baths as the multiple rooms are half buried inside the ground. The plan of the Therme Vals baths is composed of different monolith units and combine together with different roof structures joined together leaving the gap of joint and giving light a chance to penetrate inside. Figure 5: Different slabs attached with units connected together with a gap to reveal the space inside creating a visual experience of resembling a cave or quarry. To resemble the ancient baths, stone is not used as a veneer stone. Zumthor developed a tectonic masonry system in which stone is used as structural material. Conclusion: Zumthor uses materials to his full extent with a very large diversity but his designs reflect the coherence between them. His projects use the materials in their natural form, taking into consideration their characteristics and internal assembly. The program brief for the design is thought in a way that goes with a natural law of materials and hence the structure is thought complementing the design. His approach to design respects what material want; following their natural “folds”. He designs his joints in the material in way they seem hidden showing seamless transition of materials. This create a visual experience without any obstructing and eye-catching details. The spatial experience is also governed by the type a structure in his buildings. Thick walls and massy structure of the Bruder Klaus creates a dark space relatable to the universe and hence the light from oculus on the top justifies the experience. Zumthor approach towards program also connects back to the material extent. He looks program in a personified way which makes him to decide the material and hence the structure. Most of the projects sited in the extreme climates of Europe; his use of materials suffices to provide enough warmth visually. Zumthor’s attitude towards the use of materials as a main focus shows his interpretation towards program and function in an extraordinary way. The construction techniques enhancing the experience changes the focal point in his buildings. Not only these things but his unique way of deciding the main structure by complementing and gently touching the important aspects of the program brief enhances the spatial experience.