Building innovation comes in many forms, in this case, even an old basement. The parking lot at Bulley & Andrews’ (B&A) new headquarters sits on the site of the firm’s old building. When planning the new parking lot, the team identified a way to re-purpose the building’s former basement by turning it into a water retention basin, which is required by current city code.
How was it done?
After demolishing the structure, the first step in modifying the remaining basement involved pouring a new concrete floor. B&A utilized its own forces to perform this work.
Next, a waterproofing membrane was added to create a bathtub-like vessel. Two catch basins and an access lid were installed. The basin was then covered with pre-cast concrete slabs to form a lid that was also covered by a waterproof membrane to seal the entire vessel. Finally, stone was placed on top of the basin, completing the transformation from basement to basin.
How does it work?
The basin stores excess rain water and then slowly releases it into the sewer system. The slow release rate is accomplished by adding a restrictor at the end of the pipe before the water enters the sewer main. This restrictor reduces the diameter of the pipe thereby allowing the water to accumulate in the basin before being released, avoiding overflow that would stress the sewer system.
What are the benefits?
The adaptive re-use of the basement presented many benefits including:
- saving money, which could then be spent on other aspects of the headquarters project
- reducing the amount of debris sent to landfills (if the basin was created from scratch, 500 cubic yards, about 38 truck-loads, of dirt would have been excavated and sent to the landfill)
- reducing the amount of new materials needed to build a water retention basin
B&A provides innovative, responsible and sustainable construction methods to deliver the best results for our clients. Every project is an opportunity for our team to leverage innovation. Our headquarters building was no different. While our new headquarters project is complete, the lessons learned and innovative techniques employed will continue to benefit future projects.