Choosing the right metal fabrication subcontractor affects quality, efficiency, and cost-effectiveness. The wrong choice can lead to delays, subpar results, and unexpected expenses—issues no business wants.
Asking the right questions upfront helps assess whether a subcontractor has the expertise, reliability, and capacity to handle your project. This guide covers ten key questions to help you find a partner who meets your requirements and delivers the best results.
1. What is your experience with projects similar to ours?

A subcontractor with relevant experience is more likely to meet project requirements efficiently. Key points to consider:
- Ask if they have worked on projects similar in size, complexity, and industry.
- Industry-specific knowledge can improve design, efficiency, and production.
- Request examples of past projects, including challenges they have overcome.
- Find out what materials and fabrication techniques they specialise in.
- Check if they comply with industry regulations and quality standards.
2. Can you provide references or case studies from past clients?
A reliable subcontractor should have references, testimonials, or case studies that demonstrate their capabilities. Here is what you should look for:
- Examining past work helps assess a subcontractor’s ability to deliver high-quality results on time.
- Case studies provide insight into problem-solving skills, attention to detail, and overall reliability.
- Speaking to past clients can also highlight strengths and weaknesses that may not be obvious at first.
- Ask about their experience with communication, adherence to deadlines, and the quality of finished components.
3. What certifications or accreditations do you have?
Certifications demonstrate a subcontractor’s commitment to quality, safety, and compliance.
Make sure to look for:
- ISO 9001 – Ensures a strong quality management system and continuous improvement.
- Ask about their approach to workplace safety, employee training, and how they mitigate environmental impact.
- Some industries (e.g., aerospace, automotive, or medical) have additional certification requirements—check that the subcontractor meets these.
4. What materials and fabrication processes do you specialise in?
Not all metal fabricators work with the same materials or processes. Make sure the subcontractor specialises in the materials your project requires, such as stainless steel, aluminium, or mild steel. Each metal demands different handling and fabrication techniques, affecting cost, lead time, and quality.
It’s also best to understand the fabrication processes they offer. Key capabilities may include laser cutting, CNC machining, bending, welding, and powder coating. If your project requires a specific process, confirm that they have the right equipment and skilled staff to handle it efficiently.
5. What is your capacity and lead time for our project?
A subcontractor must have the capacity to take on your project without causing delays. If their workload is too high, they may struggle to meet deadlines, leading to production bottlenecks. Ask about their current capacity and how they manage multiple projects at once.
Lead times can vary depending on order size, material availability, and production complexity. Find out their typical turnaround times and how they handle urgent or large-scale orders. It’s also worth asking if they have contingency plans for unexpected delays, such as equipment breakdowns or supply chain disruptions. A subcontractor with clear scheduling processes is more likely to deliver on time.
6. What is your quality control process?

Quality control plays an important role in ensuring consistency and preventing costly rework. When evaluating a subcontractor’s approach, ask:
- What inspection methods do they use? (e.g., dimensional checks, surface finish analysis, non-destructive testing).
- Do they have in-house quality control teams, or is testing outsourced?
- What happens if a component doesn’t meet specifications? (Ask about their non-conformity handling process).
- Do they offer batch testing or first-article inspection for critical projects?
- How do they ensure consistency in repeat orders?
A structured quality assurance process ensures that every fabricated component meets your tolerances, performance expectations, and safety standards.
7. How do you handle design changes or revisions during the project?
Design changes are common in fabrication projects, so it’s best to understand how a subcontractor manages them. A well-organised process helps avoid miscommunication, delays, and unexpected costs.
Ask if they provide in-house design support to assist with modifications. Some fabricators offer CAD modelling and prototyping, which can streamline adjustments before full production begins. It’s also useful to know how changes affect pricing and lead times—will minor revisions be absorbed into the project, or will they incur extra costs?
A structured change management system prevents miscommunication and costly mistakes. Ask if the subcontractor uses revision tracking tools (such as CAD version control) and whether they provide detailed documentation for each design update. Confirm how they communicate changes with production teams to avoid manufacturing errors.
8. What are your payment terms?
Clear payment terms help prevent misunderstandings and financial issues during a project. Every subcontractor has different terms, so you need to confirm their requirements before committing to a contract.
Enquire about deposit requirements, milestone payments, and final balances. Some fabricators may require upfront payments, while others work on staged payments based on project progress. It’s also useful to check if there are penalties for late payments or unexpected changes in scope.
Clarifying these details early helps with budgeting and that there are no surprises later. A subcontractor with flexible and transparent payment terms can make financial planning easier and reduce the risk of disputes.
9. Why should I choose you over other local metal fabrication companies?
With numerous subcontract sheet metal fabrication providers available, it’s crucial to evaluate beyond price alone. Consider factors such as:
- Technology & Equipment: Does the company use CNC laser cutting, robotic welding, or automated quality checks to enhance precision and efficiency?
- Scalability & Flexibility: Can they handle both small prototypes and high-volume production with consistent quality?
- Post-Fabrication Services: Do they offer powder coating, assembly, or packaging to streamline your supply chain?
- Communication & Responsiveness: How quickly do they respond to queries, provide quotes, and manage project updates?
- Track Record & Client Retention: Do they have long-term clients in your industry, indicating reliability and expertise?
10. What types of welding methods do you offer?
Different projects require specific welding techniques, so it’s advised to confirm whether a subcontractor can meet your needs. The right welding method impacts strength, durability, and overall quality.
Common techniques include MIG welding (ideal for speed and efficiency), TIG welding (suited for precision and thin materials), and arc welding (used for heavy-duty applications). Ask which methods they specialise in and whether their welders hold industry-recognised certifications.
A subcontractor with skilled welders and the right welding processes will produce stronger, more reliable components. Checking their capabilities upfront helps avoid structural issues and means the finished product meets your specifications.
Choosing a subcontract sheet metal fabrication is a decision that affects both cost and quality.
By asking the right questions, businesses can secure a supplier that delivers precision, meets deadlines, and upholds industry standards. Prioritising experience, quality control, and flexibility provide long-term success. A well-informed choice today prevents costly mistakes tomorrow. At Greengate Metal Components, we’re here ready to hear about your projects and requirements, so get in touch today to discuss all your sheet metal needs.