Questions to Ask a Deck Builder Before You Hire Them

Why it pays to ask the right questions

A deck can add genuine value to your home, but only if it is built safely, suits your section and is finished properly. In New Zealand, deck projects can range from a simple ground-level platform to a raised structure that may need a building consent, compliance with the Building Code, and careful planning around weather, access and drainage.

The best way to avoid delays and disputes is to treat the first conversation with a deck builder like an interview. A good builder should be happy to answer detailed questions, explain what is and isn’t included, and back up their claims with written information.

Use the checklist below to compare builders fairly before you sign anything or pay a deposit.

1) What experience do you have with decks like mine?

Not every builder specialises in decks, and not every deck is the same. A builder who mainly does renovations may still be excellent, but you want to know they have built similar projects before.

Ask:

• How many decks have you built in the last 12 months?
• Have you worked on decks of a similar size, height and design?
• Do you have experience with timber, composite decking, stairs, balustrades or pergolas if those are part of my plan?
• Have you built decks on sloping sites, clay soils or coastal properties before?

Why this matters:

• Raised decks need careful structural design, fixing and bracing.
• Coastal homes may need extra attention to corrosion resistance and product selection.
• Sloping sections can mean more excavation, retaining, drainage and compliance issues.

If a builder only gives vague answers, ask for photos of completed work and addresses you can inspect from the street.

2) Are you licensed, insured and able to do the work legally?

This is one of the most important parts of the conversation.

In New Zealand, many deck builds are carried out by general building contractors rather than licensed trades in a separate trade register. However, you should still check that the builder is operating legitimately and understands when other regulated work is involved.

Ask:

• What is your company name and NZ Business Number?
• Do you carry public liability insurance?
• Do you have contract works insurance while the deck is being built?
• If your team includes electricians, are they registered and licensed with the EWRB?
• If the project includes plumbing, gasfitting or drainlaying, who will do that work and are they authorised under the PGDB?

Key NZ reminders:

• Electrical work is regulated by the Electrical Workers Registration Board (EWRB).
• Plumbing, gasfitting and drainlaying are restricted work under the Plumbers, Gasfitters and Drainlayers Board (PGDB).
• Deck construction itself is building work, and some decks need a building consent from your local council.

Ask for copies of insurance certificates and any relevant licence or registration details. A professional builder should not be defensive about this.

3) Will this deck need a building consent?

Before you hire anyone, ask how they will determine whether consent is needed.

A deck may need a building consent if it is:

• high enough above ground to trigger consent requirements
• attached to the house in a way that affects structural support
• part of a larger alteration or addition
• combined with stairs, balustrades, pergolas or retaining structures that create compliance issues

Rules can change and local councils can interpret situations differently, so don’t rely on assumptions like “it’s only a small deck” or “my neighbour didn’t need one.”

Ask:

• Will you confirm whether my deck needs consent before quoting?
• Will you prepare drawings and specifications for council if required?
• Have you handled council inspections and code compliance paperwork before?
• If consent is needed, is that included in your price or extra?

A good builder will be upfront about the process and should encourage you to verify requirements with the local council before work begins.

4) What exactly is included in your quote?

Quotes can look similar at first glance but hide very different scopes of work. The cheapest quote is not always the best value if it excludes site prep, fixings, consent fees or finishing details.

Ask for a written quote that clearly states:

• deck size and dimensions
• materials and product brands
• subframe specification, posts, bearers and joists
• decking board type, profile and colour
• stairs, handrails and balustrades if included
• excavation, carting away spoil and site clean-up
• staining, oiling or painting
• fixings, flashings and corrosion-resistant hardware
• council consent costs, if applicable
• GST status

Useful comparison tip:

If a quote says “all materials included” but does not specify what those materials are, ask for a detailed breakdown.

5) How do you handle variations or unexpected site conditions?

Many deck projects uncover surprises once work starts. Common examples include soft ground, hidden services, difficult access, rotten timber near the house, or the need for extra footing depth.

Ask:

• What happens if you find a problem once work begins?
• How do you price variations?
• Will you get my written approval before doing extra work?
• Do you charge for delays caused by weather or council inspections?

This is especially important in New Zealand, where winter rain, wet ground and stormy conditions can slow earthworks and framing. A builder should explain how weather affects their programme and what they will do to protect materials on site.

6) What is your expected timeline and work programme?

A deck build can take anywhere from a few days to several weeks depending on size, consent, weather and material availability.

Ask:

• When could you start?
• How long do you expect the job to take?
• Will you be on site every day or working between other jobs?
• Who will manage the project?
• How do you handle delays if it rains or if materials are delayed?

In peak seasons, especially spring and early summer, good deck builders can book out weeks or months ahead. If you want your deck ready for summer entertaining, it is wise to organise the job early.

Also ask whether the builder will sequence the work around local council inspections if consent is required, because that can affect the programme.

7) Who will actually do the work on site?

Some builders personally lead the job, while others use subcontractors or apprentices for parts of it. There is nothing wrong with either approach, but you should know who is responsible for quality and communication.

Ask:

• Will you be on site personally?
• Will any subcontractors be used?
• Who is my main point of contact?
• How do you supervise workmanship and safety?
• Are your workers covered by ACC and appropriate insurance?

If the builder uses subcontractors for electrical work, drainage, or specialised tasks, ask for the subcontractor’s licence details and confirmation they are qualified for that work.

8) Can I see references and recent examples of your work?

References are one of the best ways to test whether a builder is reliable.

Ask for:

• two or three recent client references
• photos of completed decks from different stages of the build
• examples of projects similar to yours
• addresses of completed jobs you may be able to view from the road

When speaking to references, ask practical questions:

• Was the quote accurate?
• Was the builder easy to deal with?
• Did they turn up when promised?
• Was the site left tidy?
• Were there any unexpected costs?
• Would you hire them again?

Recent work matters more than old testimonials. You want proof of current workmanship and service, not just polished marketing.

9) What guarantees or workmanship warranty do you offer?

A reputable deck builder should stand behind their work, but guarantees vary widely.

Ask:

• Do you provide a written workmanship warranty?
• How long does it last?
• What does it cover and what does it exclude?
• Are materials covered by the manufacturer separately?
• How do I report a defect if something goes wrong?

Be careful not to confuse a workmanship warranty with a product warranty. For example, composite boards, fixings and stains may have their own manufacturer terms, while the builder is responsible for installation quality.

Ask for the warranty in writing, including the process for repairs or remedial work.

10) How do you handle safety, access and site protection?

Deck building can affect driveways, gardens, fences and neighbours. A professional builder should plan for safe access and protect the rest of your property.

Ask:

• How will you protect existing landscaping and outdoor furniture?
• Where will materials be stored?
• How will you manage dust, noise and rubbish?
• What steps will you take to keep the site safe for children and pets?
• Will you organise barriers or signage if needed?

If your section is tight or close to neighbouring boundaries, ask how they will manage access without causing damage or disputes.

11) How do payments work?

Never agree to a payment schedule that feels unclear or front-loaded.

Ask:

• Do you require a deposit?
• What are the milestone payments?
• Is the final payment due only after completion and any required inspection sign-off?
• Do you issue GST invoices?

A fair payment schedule usually follows progress, not just time. Avoid paying large amounts upfront unless the builder can clearly justify material ordering or other early costs, and always get it in writing.

12) What should be in the written contract?

Before you commit, ask for a written contract that reflects the quote and clearly sets out the job.

It should include:

• the builder’s full legal name and contact details
• scope of work and plans
• materials and finishes
• price and payment schedule
• start and completion dates or estimated programme
• consent responsibilities, if relevant
• variation process
• warranty details
• dispute process

If anything is missing, ask for it to be added. Verbal promises are difficult to prove later.

A quick checklist before you hire

Use this final checklist when comparing deck builders:

• Get at least two or three written quotes
• Confirm experience with similar decks
• Check insurance and any relevant registrations for electrical or plumbing-related work
• Ask whether building consent is needed
• Compare inclusions, exclusions and variations carefully
• Ask about timeframes, weather delays and site supervision
• Speak to recent references
• Get guarantees and payment terms in writing

Final thoughts

A good deck builder will welcome careful questions. In fact, the more transparent they are about consent, costs, timing and workmanship, the more confidence you can have in hiring them.

Take your time, compare quotes properly and check credentials before you sign. A little extra diligence at the start can save you a lot of stress, delay and expense later.