Dönni Solar & Bau provides customized solar solutions for residential and commercial clients. From consultation and planning to the installation of photovoltaic systems, we focus on sustainable energy and top-quality service. Our expertise includes roof renovation, building technology, and energy efficiency solutions. Benefit from eco-friendly solar power and optimize your energy costs. With cutting-edge technology and years of experience, we help you transition to renewable energy.

Project Evolution SA is a company specialized in the construction of energy-efficient wooden houses and buildings. With over 20 years of experience and an operational headquarters in Grono (Canton of Graubünden) since 2020, it is organized to operate throughout Switzerland , managing every construction phase: from planning to final delivery. We work with Swiss precision and a rigorous technical approach, focusing on site organization, timeline compliance, and cost transparency. Structures and Building Systems • Wooden structures using X-LAM system with high static and energy performance • Prefabricated eco-friendly walls , with battens, double mineral wool insulation, and breathable finishes • Custom solutions for single-family homes, villas, extensions, elevations , and multi-storey buildings (up to 7 floors) Insulation and Living Comfort • Natural breathable insulation in rock wool or wood fiber • External thermal insulation systems using ecological, high-efficiency materials • Drywall partitions and suspended ceilings , perfectly smoothed and finished • Carefully executed interior finishes: smoothing, leveling, and surface preparation Interior Works and Installations • Supply and installation of high-efficiency windows and doors • Interior wall cladding and partition walls in drywall • Full coordination of technical installations (electrical, plumbing, mechanical ventilation) Sheet Metal and Roofs • Construction of ventilated and waterproof roofs • Custom-made metal sheet works : copper, aluminum, stainless steel • Gutters, flashings, chimney caps, and external finishes with maximum attention to detail Logistics and Material Transport Even the most complex construction sites are no challenge for us: we transport materials using any necessary method, including crane trucks, tractors, helicopters , or special solutions for isolated or hard-to-reach areas. Efficient organization is one of our core values. Why Choose Project Evolution SA • ✅ Over 2,000 projects completed in Switzerland and Italy • ✅ Advanced shell approach , with a single technical point of contact • ✅ Accuracy in installation, hidden details, and site management • ✅ On-time and on-budget delivery, no surprises • ✅ Expertise in eco-construction and certified natural materials • ✅ Solid experience with prefabricated and sustainable buildings Building with wood in Switzerland? Trust Project Evolution SA We create your eco-friendly wooden house, your sustainable building, or your custom project with maximum technical competence and attention to detail. From design to installation – we are by your side at every step. 📍 Active throughout Switzerland – Contact us for a quote or a personalized consultation.