When you need a licensed professional

Some work has to be designed by a licensed professional, performed by a licensed contractor, or both. Which work, and where the line falls, is decided by the office handling your application — so this page explains the roles and the signals, and points you to the one place that can answer for your project.

The two different questions

People often merge these, but they're separate.

Who designs it? Some projects need drawings prepared and stamped by a licensed architect or engineer. A stamp is that professional taking legal responsibility for the design.

Who builds it? Some work must be carried out by a licensed contractor in the relevant trade.

You might need both, one, or neither. They're decided by different rules.

Signals you probably need a professional

None of these are rules — they're prompts to ask:

• Structural work — removing or altering load-bearing walls, changing the roof structure, adding a floor
• Change of use — converting a garage to living space, a house to apartments, residential to commercial
• Size or value — many places set a threshold above which stamped drawings are required
• Trades with life-safety implications — electrical, gas, plumbing, and mechanical work often carry licensing requirements
• Commercial or multi-family work, which is usually held to a higher standard than a single-family home
• Anything in a special district — flood zone, historic overlay, coastal or environmental designation

Doing the work yourself

Many organisations let an owner apply for and perform work on their own property. Many restrict which trades that covers. Some don't allow it at all.

This is one of the most variable rules in permitting, and getting it wrong is expensive — work performed without the required license may have to be redone regardless of quality.

Ask the office handling your application before you start, and ask specifically: can I do this work myself, and can I pull the permit myself? The answers aren't always the same.

Why it's worth confirming early

Finding out mid-review that your drawings need a stamp means going back to the beginning of the design — hiring someone, waiting for drawings, resubmitting, waiting for review again. Finding out at inspection that the work needed a licensed installer is worse.

A single call before you start is the cheapest thing on this page.

Who to ask

The office at the phone number shown on your portal or the email address shown on your portal, their published hours.

Have ready: the property address, a plain description of the work, and roughly what it will cost. That's usually enough for staff to tell you what your project needs.