TL;DR:
- Hiring a contractor without checking references is like buying a car without inspecting its engine, risking costly issues later. Focus on recent, verified references from primary decision-makers to assess reliability, work quality, communication, and post-project support effectively. Asking if they would hire the contractor again offers the clearest insight into overall trustworthiness and performance.
Hiring a contractor without speaking to their references is a bit like buying a car without looking under the bonnet. The finished product might look fine, but you have no idea what is actually holding it together. Asking the right questions to ask a reference for a contractor separates property owners who make confident decisions from those who end up with costly disputes, incomplete work, or contractors who disappear when problems arise. This guide gives you a structured, practical list of questions to use during your next contractor reference check, so you hire with your eyes open.
Table of Contents
- Key takeaways
- Questions to ask a reference for a contractor: where to start
- 1. What type of work did the contractor complete for you?
- 2. Was the work completed on schedule?
- 3. Did the final cost match the original estimate?
- 4. How did the contractor handle unexpected problems?
- 5. How was the contractor’s communication throughout the project?
- 6. Was the worksite kept clean and safe?
- 7. Was the quality of workmanship what you expected?
- 8. Would you hire this contractor again?
- 9. Did the contractor manage subcontractors well?
- 10. Were there any issues after the project was completed?
- Comparing question focus areas: a quick reference guide
- What I have learnt about making reference checks actually work
- Hire with confidence: how Prowaterproofing can help
- FAQ
Key takeaways
| Point | Details |
|---|---|
| Recency of references matters | Only accept references from projects completed within the last 12 to 18 months to reflect current contractor quality. |
| Ask about willingness to rehire | This single question reveals more about contractor reliability than most technical questions combined. |
| Verify references independently | Confirm project addresses and client roles yourself rather than relying solely on contractor-provided contacts. |
| Assess process, not just results | Ask about communication, site management, and problem-solving as well as the finished work. |
| Watch for red flags | Reluctance to provide references or only offering written testimonials is a strong warning sign. |
Questions to ask a reference for a contractor: where to start
Before you dial a single reference, you need to know whether that reference is worth calling. Not every contact a contractor gives you is equally valuable, and some carry very little weight at all.
References from projects completed recently are the only ones worth prioritising. A contractor’s team, financial health, and working standards can shift significantly over time, so a glowing review from three years ago may have nothing to do with the person who will show up at your property today.
Key checks before you begin your inquiries:
- Confirm the reference was the primary decision-maker on the project, not a neighbour or family friend.
- Ask the contractor for at least three references, not one. Patterns across multiple contacts reveal far more than a single opinion.
- Verify reference legitimacy by confirming project addresses and the reference’s role through public records or a quick site visit if practical.
- Be wary of contractors who offer only written testimonials or hesitate when asked for direct contact details.
Pro Tip: If a contractor is reluctant to share references, treat it as a serious warning. Reputable contractors willingly share contact information for satisfied clients without hesitation.
1. What type of work did the contractor complete for you?
Start every reference call by establishing context. Knowing the scope and nature of the project helps you judge whether that reference’s experience is relevant to yours. A contractor who did excellent interior painting may not have the same track record for structural waterproofing or roofing repairs.
Ask the reference to describe the project briefly: size, duration, and the primary trades involved. This also tells you whether the contractor has recent experience with projects of similar complexity to what you need. A simple bathroom renovation and a full commercial waterproofing installation are worlds apart in terms of management demands.
2. Was the work completed on schedule?
Delays are one of the most common complaints property owners have about contractors. This question cuts straight to reliability. Ask the reference whether the project finished by the agreed date, and if not, how large the overrun was and whether they were kept informed throughout.
Follow-up questions worth adding here: Were there delays caused by the contractor specifically, or by material shortages or weather? How did the contractor communicate when timelines slipped? Did they take ownership of the problem or point fingers at external factors?
A contractor who communicates delays proactively and adjusts plans accordingly is far more professional than one who goes quiet and hopes nobody notices.
3. Did the final cost match the original estimate?
Budget creep is another area where contractors can cause serious damage to a client relationship. Ask the reference whether the final invoice aligned with the original quote, and how any additional costs were handled along the way.
Written change orders that detail both cost and schedule impacts before work proceeds are the mark of a well-managed project. A contractor who performs extra work and then surprises a client with a larger bill at the end is demonstrating poor project management at best, and dishonest practice at worst.
Ask the reference:
- Were change orders always documented and approved before work began?
- Were additional costs explained clearly and justified with reason?
- Did any costs appear without prior discussion or written agreement?
4. How did the contractor handle unexpected problems?
Every construction project encounters surprises. What separates a reliable contractor from a poor one is how they respond when things go sideways. This is one of the most revealing questions for contractor references because it forces the reference to recall a real situation rather than give a rehearsed positive answer.
Ask whether anything unexpected came up during the project, such as hidden structural damage, material availability issues, or subcontractor problems. Then ask what the contractor did about it. Did they present options and let the client decide? Did they act without consulting anyone? Did they absorb minor costs or immediately bill for everything?
References provide critical insight into exactly this kind of daily management behaviour, and no portfolio or online review will tell you what a contractor does when pressure builds.
5. How was the contractor’s communication throughout the project?
Poor communication is behind most contractor disputes. Even when the physical work is solid, a contractor who is hard to reach, vague about progress, or dismissive of concerns will cause unnecessary stress for any property owner.
Ask the reference whether they could contact the contractor easily when they had questions. Ask whether updates were offered proactively or only when the client chased for information. Find out whether the contractor was clear about what was happening on site each week and whether the reference ever felt left in the dark.
You are looking for a contractor who treats communication as part of the job, not an afterthought. Insights from evaluating contractor processes like communication and responsiveness are as telling as any quality of workmanship question.
Pro Tip: Ask the reference how long the contractor typically took to respond to calls or messages. A pattern of taking more than 24 hours to reply during active work is a signal worth noting.
6. Was the worksite kept clean and safe?
Site management reflects a contractor’s professionalism more than most people realise. A chaotic, unsanitary, or hazardous worksite is not just unpleasant. It increases the risk of accidents, signals disorganisation, and often predicts poor quality in the finished work.
Ask the reference whether the site was tidy at the end of each working day. Were materials stored safely? Were access points secured when the team left? Did the contractor manage subcontractors well, or did different trades create confusion and conflict on site?
For residential property owners especially, these details matter. You are not just hiring a tradesperson. You are inviting a team into your home or building, and the way they manage that space says a great deal about how they run their business.
7. Was the quality of workmanship what you expected?
This is the core of any reference check. Ask the reference to assess the quality of the finished work honestly. Were there defects or punch-list items that needed addressing? How were they handled once raised?
A workmanship warranty is typically one to two years for residential construction, and all warranty terms must appear in writing to be enforceable. Ask the reference whether the contractor honoured any warranty obligations that arose after project completion, or whether they became difficult to reach once the final payment was made.
Also ask about the finer details: Were finishes neat? Were materials of the standard specified? For waterproofing or tiling work, you can check relevant guides such as renovation quality benchmarks for context on what acceptable workmanship looks like across different trade areas.
8. Would you hire this contractor again?
This is the single most revealing question you can ask, and it should not be skipped. The willingness to rehire a contractor tells you more about their overall reliability and value than any individual technical question.
Listen carefully to the answer. A confident “yes, absolutely” is meaningful. A hesitant “probably, for smaller jobs” or “maybe, but I would be more careful about the contract this time” reveals reservations the reference may not have stated outright. When you hear qualifiers, probe further. What would they do differently? What would they want clearer in writing next time?
This question works precisely because it forces the reference to weigh everything together and give you their honest, overall verdict.
9. Did the contractor manage subcontractors well?
Most contractors bring in specialist subcontractors for certain parts of a project. The question is whether the main contractor takes ownership of their subcontractors’ work and behaviour, or whether they treat subcontractor problems as someone else’s responsibility.
Ask the reference whether any subcontractors caused problems on the project and how the main contractor handled it. Did they step in and resolve issues, or did they leave the client to deal with complications directly? A strong contractor manages their supply chain. A weak one uses subcontractors as an excuse.
For roofing, waterproofing, and other technical trades, site management and coordination between trades is particularly important, since poor handoffs between teams can compromise the entire installation.
10. Were there any issues after the project was completed?
Post-completion problems are often where contractor quality truly reveals itself. Ask the reference whether any defects, leaks, or failures appeared in the weeks or months after the project wrapped up. More importantly, ask how the contractor responded.
Did they return promptly to investigate and repair the issue? Did they dispute responsibility? Did they go silent? For waterproofing in particular, post-installation performance is the ultimate test of workmanship. A contractor who stands behind their work and returns without drama when something goes wrong is worth their weight.
Comparing question focus areas: a quick reference guide
Use this table to decide which questions to prioritise based on what matters most to your project.
| Question focus | What it reveals | Priority for large projects |
|---|---|---|
| Schedule adherence | Reliability and time management | High |
| Budget and change orders | Financial honesty and transparency | High |
| Communication | Professionalism and client respect | High |
| Workmanship quality | Technical skill and attention to detail | High |
| Post-completion support | Integrity and warranty commitment | Medium to high |
| Site management | Organisation and safety culture | Medium |
| Subcontractor management | Leadership and accountability | Medium |
Pro Tip: Weight your questions towards communication and post-completion support if you are hiring for waterproofing or any trade where defects may only appear weeks after the work is finished.
What I have learnt about making reference checks actually work
I have reviewed dozens of contractor reference situations over the years, and the pattern is always the same. Property owners who ask surface-level questions get surface-level answers. The reference says the work was good, the contractor was nice, and everything went fine. And then the property owner hires based on that, only to discover later that “fine” meant something very different to the reference than it means to them.
The “would you hire them again” question is the one I trust most. I have seen cases where a reference answered every technical question positively but paused on that one. That pause told the whole story. When I dug further, the reference admitted the contractor had been excellent with the physical work but had been unreachable for three weeks mid-project, which had caused real stress at the time.
I also believe in verifying references independently rather than calling whoever the contractor hands you. Ask for a project address, then call the property owner you find through your own search rather than using only the number provided. It sounds like extra effort, but it removes any chance that the “reference” is actually a friend doing the contractor a favour.
The other thing I would stress: do not let one glowing reference cancel out a concern raised by another. Patterns matter. If two out of three references mention the same issue, even in passing, that is the reality of working with that contractor.
— Eben
Hire with confidence: how Prowaterproofing can help
Checking references thoroughly is only one part of hiring a contractor you can trust. At Prowaterproofing, we connect property owners with vetted waterproofing specialists who meet professional insurance and warranty standards from the outset. Our contractors carry the liability cover that protects property owners from financial exposure, and every project includes clearly documented warranty terms.
If you want to go deeper into what to ask before signing a contract, our guides on waterproofing contractor questions and essential contractor questions give you a full framework for confident hiring. When you are ready to get a quote from a contractor you can genuinely verify, start at Prowaterproofing.
FAQ
What is the most important question to ask a contractor reference?
Ask whether the reference would hire the contractor again. This single question reveals more about a contractor’s overall reliability than any technical inquiry because it forces the reference to weigh their entire experience and give an honest verdict.
How recent should contractor references be?
References should be from projects completed within the last 12 months. Older references may not reflect a contractor’s current team, standards, or financial stability.
What is a red flag when checking contractor references?
A contractor who hesitates or refuses to provide direct references is a significant warning sign. Reputable contractors share client contact details readily, and offering only written testimonials in place of direct contacts suggests something is being concealed.
Should I verify contractor references independently?
Yes. Confirm the project address and the reference’s role yourself rather than relying entirely on contractor-provided contacts. Prioritise references who were the primary decision-maker on the project, not neighbours or associates of the contractor.
What should I ask about contractor warranties during a reference check?
Ask whether the workmanship warranty was honoured if any defects arose after the project finished. Residential workmanship warranties typically cover one to two years, and all terms must be in writing to be enforceable.