What Questions Should You Ask a Deck Builder Before Hiring Them?

Most homeowners ask the same three questions when they're evaluating a deck contractor: Are you licensed? Are you insured? Can I see some photos of your work?

Those are fine questions. But they're also the floor — the minimum you'd expect from anyone worth talking to. They don't tell you whether the contractor knows how to protect your home from water damage at the ledger connection, whether their pricing is based on real data or an educated guess, or whether the experience of hiring them will be consistent or chaotic.

After 11 years in this trade and over 200 completed projects in Northeast Wisconsin, here are the questions I'd ask if I were the homeowner — and what the answers actually tell you.

1. Who Is in Charge of Quality Control on Your Jobs?

This is the single most revealing question you can ask any contractor. The answer tells you immediately whether their business runs on systems or on heroics.

A contractor who says "I'm on every job site" isn't necessarily giving you a bad answer — it depends on whether you trust that person and whether they have the capacity to actually be present every day across multiple active projects. But it's a personal answer, not a systems answer. It means quality depends on that one individual showing up.

When someone asks me that question, my answer is different: every Tech Five project gets a build packet when the contract is signed. It walks step by step through the entire build — ledger installation, footings, framing, decking, railing, fascia — with dimensions, spacing, and stop-and-check points that are reviewed and signed off at each stage. The accountability isn't tied to whether I personally happen to be standing there. It's built into the process.

That's what makes the customer experience repeatable. We already know exactly what we're building before the first board goes down. There's no guessing in the field.

When you ask this question, listen for specificity. A strong answer describes a process. A weak answer describes a person.

2. How Do You Handle Water Management at the Ledger Connection?

Water is the enemy of a deck for its entire life — from the house attachment all the way down to the footings. Most of the visible parts of a deck, the boards, the railing, the fascia, are well-engineered today and hold up well when installed correctly. The vulnerability is at the connection points, and the most critical one is where the deck frame attaches to your house.

Proper ledger flashing is required by code for a reason. It involves a metal drip edge overlapping the ledger by at least 3 inches, silicone sealant applied behind the drip edge in the corner where it meets the house, and careful attention to the detail at the top of the ledger board. When it's done right, water that gets behind the deck surface is directed away from the wall. When it's not done right — or skipped entirely — water follows the path of least resistance directly into your wall.

In my experience removing 10 to 15 year old decks from relatively new homes in Northeast Wisconsin, I have found water damage to first-story walls and walkout basement walls in 100% of cases where the flashing was not properly installed. Not most cases. Every single one. The damage is often invisible from the outside until a deck comes off and the wall framing is exposed.

Ask your contractor specifically how they flash the ledger and what sealant they use. If the answer is vague or they seem unfamiliar with the detail, that's meaningful information.

3. Do You Use Joist Tape on the Frame?

This one surprises homeowners because it sounds minor. It isn't.

Joist tape — a moisture-barrier tape applied to the top edge of every framing member before decking goes down — seals the V-groove that forms where a deck board sits on a joist. That groove is where water collects and where rot starts. Without tape, treated lumber frames degrade from the top down, often invisibly until the frame is structurally compromised.

Beyond the structural argument, most composite and PVC decking manufacturers require joist tape as a condition of their warranty. If a contractor skips it, the warranty on your decking surface may be void from day one — regardless of how good the boards are.

It's a small line item. Contractors who skip it are saving maybe a few hundred dollars on a $25,000 job. Ask whether it's included. The answer tells you something about how thorough the rest of the build will be.

4. What Type of Footings Do You Use and Why?

Wisconsin's freeze-thaw cycle, clay soil conditions, and frost depth requirements make footing selection more consequential here than in many other parts of the country. This is not a one-size-fits-all answer.

On over 90% of the decks we build, we use Diamond Pier helical pin footings. They were engineered in Minnesota specifically for freeze-thaw performance, have been in use for nearly 30 years, and the data on their performance versus traditional concrete tube footings is not close. I have never had one move. They go in faster than digging and mixing concrete, they eliminate the extra footing inspection required for concrete, and because they're a manufactured product with a warranty, there's no variability from an inconsistent concrete cure.

That said, the right answer to this question isn't specifically "Diamond Piers" — it's a contractor who can explain their footing choice and connect it to the specific soil and climate conditions of your site. A contractor who says "we just pour tube footings" without any further explanation of depth, diameter, or why that choice is appropriate for your lot is worth pressing further.

Want to ask these questions in person? At a Tech Five design consultation, we walk through every one of these details — flashing, footings, joist tape, quality control — before you ever make a decision. No pressure, real answers. Book your consultation.

5. Do You Pull the Permit, and What Does That Process Look Like?

In Wisconsin, pulling a building permit for a deck requires a dwelling contractor license and a dwelling contractor qualifier. Insurance is required by state law. These are not optional and they are not difficult to verify — but you should verify them.

More importantly: make sure the contractor is pulling the permit, not asking you to pull it yourself. A contractor who asks the homeowner to pull their own permit is transferring the legal liability for code compliance to you. If the deck doesn't pass inspection — or was never inspected — that's your problem when you go to sell the house or make an insurance claim.

In our experience, homeowners who are working with a contractor whose operation looks professional — proper contracts, a real website, clear scope documents — rarely need to dig into the licensing question. The overall presentation answers it. But confirming verbally that your contractor is licensed, insured, and pulling the permit themselves takes thirty seconds and removes any ambiguity.

6. How Is Your Pricing Derived — and What Happens If the Job Takes Longer Than Expected?

This question gets at the difference between a fixed-price proposal and an estimate.

A real fixed-price proposal means the contractor has derived the material quantities to the piece, allocated labor based on actual tracked data from comparable projects, and accounted for overhead honestly. The number on the proposal is the number on the invoice. The only thing that changes it is a scope change you initiate.

An estimate is different. It's a number the contractor thinks the job will cost, padded by however much buffer their experience suggests. When the job runs over — and for contractors who haven't built enough of the right kind of projects, it often does — you find out what kind of proposal you actually signed.

Ask specifically: is this a fixed-price contract or an estimate? Ask what happens to the price if the project takes longer than planned. A contractor who has done this work long enough to price it accurately will answer that question directly and confidently. One who hasn't will hedge.

7. What Products Do You Spec and Why?

A deck specialist should be able to explain the differences between composite and PVC decking, between AZEK, TimberTech, and Trex product lines, and between standard aluminum railing and cable or panel systems — not from a brochure, but from having installed them and seen how they perform over time.

If a contractor says "we use whatever you want" without any guidance, that's not expertise — that's indifference. The right contractor will have recommendations based on your specific project, your climate exposure, your maintenance preferences, and your budget. They'll tell you what they've seen hold up and what they've seen disappoint.

We've built over 200 decks with AZEK, TimberTech, and Trex products in Northeast Wisconsin. We know how they look after three winters and how they look after eight. Those observations shape what we recommend — and we'll tell you specifically why.

The Question That Tells Us a Homeowner Is Ready to Have a Real Conversation

From the contractor's side, there's one thing that separates a productive consultation from one that goes in circles: a homeowner who's willing to talk budget.

You don't have to have an exact number. A range is fine. But when a homeowner comes in with a sense of what they're working with, the entire conversation becomes more useful. We can align the scope, the materials, and the design to what actually makes sense for their situation — rather than designing something they love and then finding out the number doesn't work.

Sharing your budget isn't a negotiating disadvantage. A contractor who uses your budget number against you isn't someone you want to hire anyway. A contractor who uses it to help you get the most out of what you have — that's the conversation worth having.

The homeowners who get the best outcomes are the ones who show up prepared to have that conversation. They know roughly what they want, they've looked at some finished projects, and they're ready to talk about what matters most to them. From there, our job is to make it happen.

If you're in the process of evaluating deck builders in Northeast Wisconsin, we're happy to answer every one of these questions in person. Bring your questions, bring your budget range, bring your inspiration photos. We'll bring the samples, the process, and the pricing. Read more about Tech Five, see our full process, or schedule your design consultation.