Designing a modern, eco-friendly house with dimensions of 5 meters in width, 10 meters in length, and spanning 3 floors is an exciting architectural challenge. This innovative residence, measuring 2500 square feet, harmoniously blends contemporary aesthetics with sustainable living, all while featuring a refreshing pool area that invites relaxation and recreation. 

The facade of the house exudes a sleek, minimalist charm with its clean lines and geometric shapes. Its exterior is predominantly adorned in varying shades of lush green, with the incorporation of sustainable materials such as recycled wood and energy-efficient glass panels, ensuring the structure seamlessly integrates with the surrounding environment.

The ground floor showcases an open-concept living space, where large glass windows and sliding doors allow ample natural light to flood in while providing a panoramic view of the picturesque garden and the shimmering pool. The living room features a minimalist fireplace and modern, eco-friendly furnishings that exude both comfort and style. The kitchen boasts state-of-the-art appliances and sustainable countertops, and it opens to a dining area that leads out to a covered patio where al fresco dining becomes a delightful routine.

A floating staircase, crafted from recycled steel and wood, leads to the upper floors. On the second floor, you'll find the spacious bedrooms, each with large windows offering sweeping views of the greenery. These rooms are designed to optimize energy efficiency, with smart climate control systems ensuring comfort throughout the year.

The third floor houses a multi-purpose loft space that can serve as a home office, entertainment area, or an additional bedroom. Large skylights and expansive windows on this level bring in even more natural light, reducing the need for artificial lighting during the day.

The highlight of this sustainable haven is the inviting pool area, strategically positioned in the backyard to optimize sun exposure and create a tranquil oasis. Native plants and a rainwater harvesting system contribute to the overall eco-friendliness of the design.

In conclusion, this 3-story, 2500-square-foot modern green house combines contemporary design with eco-conscious living. Its elegant simplicity, sustainable features, and refreshing pool area make it the perfect retreat for those who seek both style and environmental responsibility in their home design.