How to Hire for a Heating & Plumbing Business

If you’re turning down work or find yourself completely snowed under with admin and paperwork, it’s time to make a hire and expand the business. 

The catch is that “hiring” means two very different things depending on where the pressure is coming from.

• Can’t get to all the jobs? You need another gas engineer.
• Jobs are fine but the office is drowning? You need admin support.

This guide covers it all for heating businesses, and explains how GES can help with growing, engineer-led teams. 

How to know you’re ready to hire

A few signs it’s time:

• You’re turning down work you’d normally take.
• Admin is eating your evenings and weekends.
• Customers are waiting too long for quotes, certificates, or callbacks.
• You can’t take a day off without the business grinding to a halt.

One or two of these on a busy week is normal. All of them, every week, means you’ve outgrown doing it all yourself.

If you’re a sole trader weighing up your very first hire, there’s a full breakdown of the signs and the setup in our guide to hiring your first engineer.

Hiring a gas engineer

Apprentice or qualified engineer?

A qualified engineer is productive almost straight away. The catch is they cost more and good engineers can be difficult to find.

An apprentice is the long game. You get cheaper help while they learn, someone trained your way who tends to stick around, and a first step towards stepping back yourself one day. The trade-off is time: for the first year you’re investing time in them, not saving it.

We’ve weighed it up properly in Should You Take On an Apprentice in 2026?

Where to find good engineers

Good engineers rarely sit on job boards for long, so it pays to look in more than one place:

• Word of mouth. Ask the engineers and suppliers you already know. A recommendation from someone whose work you trust beats a CV every time.
• Trade Facebook groups. Local and national gas groups are full of engineers, and a post costs nothing.
• Local colleges and training providers. Good for newly qualified engineers and apprentices if you’re open to bringing someone on and training them up.
• Job boards like Indeed and Reed. Wider reach, but more applications to sift and more time-wasters.
• Recruitment agencies. They do the legwork, but expect to pay a fee worth a chunk of the first year’s salary.

What hiring an engineer costs

Salaries for gas engineers range from £25,000 to £45,000 depending on experience, qualifications, location, and other factors.

The salary is only part of it. On top of the wage you’re paying employer’s National Insurance, pension contributions, and holiday and sick pay. Then there’s a van, tools, workwear, and adding them to your insurance.

Add it up before you commit, because the true figure is usually higher than owners expect. Use our employee cost calculator for a more accurate figure.

Writing the job advert

Your job description has to sell your business.

Be specific about the pay. “Competitive salary” gets scrolled past. A real figure or range gets clicks. Say what the work is (domestic, commercial, service, installs), where it’s based, and what’s good about working for you: a decent van, sensible hours, modern kit, a boss who was on the tools himself. Keep it short and human.

Click below to expand a template you can fill out and modify for your hiring process. 

Interviewing and choosing

Before you interview anyone, write two lists: what you need and what you’d like. Needs are non-negotiable, like the right Gas Safe tickets and a clean licence. Wants are the nice-to-haves. It stops you talking yourself into the wrong person because you got on with them.

Look for attitude as much as skill. You can teach someone your way of working, but you can’t easily teach someone to care. And try not to interview alone, because a second opinion catches things you’ll miss. There’s more on running a good interview process in our hiring tips guide.

Onboarding and keeping them

The first few weeks set the tone. Get their paperwork, kit, and system access sorted before day one so they’re not stood around. Send them out with you or a senior engineer for the first jobs rather than throwing them in at the deep end.

Keeping a good engineer comes down to the basics: pay them fairly, keep the work steady, give them decent kit, and don’t bury them in admin they can’t stand. In a trade this short on people, the businesses that hold on to staff are the ones worth working for.

The legal bits before day one

Whichever route you take, a few things have to be in place before someone starts:

• Register as an employer with HMRC and set up PAYE. Do it before the first payday.
• A written contract and statement of employment terms.
• Employers’ Liability insurance, a legal requirement the moment you take someone on. See our full guide to insurance here. 
• A workplace pension, with auto-enrolment where the employee qualifies.
• Right-to-work checks before they start.

None of it is complicated, but skipping it gets expensive.