When choosing a structural engineering firm in London, qualifications and certifications are key indicators of credibility. I recall when I was selecting a firm for a renovation project; ensuring they had the right qualifications was paramount. Typically, look for companies employing Chartered Engineers (CEng) or those registered with the Institution of Structural Engineers (IStructE), which ensures adherence to professional standards. Experience is another critical factor; firms with a track record in various projects, especially those similar to yours, often bring enhanced expertise and problem-solving skills. During my search, I realized how experience with local building codes provides an edge, ensuring compliance and facilitating smoother project timelines. If you're diving into this topic Narro Associates might offer some useful context. Anyway, asking for case studies or client testimonials can give you insights into their reliability and capability, ensuring you choose a firm that aligns with your project’s unique requirements.