When you do (and don’t) need to call a plumber

Learn which plumbing jobs are DIY-friendly and which ones need professional attention. Plus, learn how to tell when it’s time to call a qualified plumber.

Shakespeare once said, “To plumber or not to plumber”, didn’t he?


Oh, right, okay then. Our mistake.

It’s a good question, though. What domestic plumbing jobs can you take care of yourself, and which ones are best left to the professionals?

While some jobs are fairly simple DIY fixes, others shouldn’t be approached with a “How hard can it be?” mindset. Sometimes, you just have to wave the white flag and call a qualified plumber.

In this guide, we look at:

What plumbing jobs need a professional?

  1. Major plumbing installations or remodels
  2. Main water line repairs
  3. Mould issues related to plumbing
  4. Water pressure issues
  5. Commercial Plumbing
  6. Emergency plumbing jobs

The benefits of hiring a professional plumber

How to tell when it’s time to contact a professional

Plumbing problems that you can fix yourself

What plumbing jobs need a professional?

Sorry to break it to you, but sometimes your inner Bob the Builder just isn’t up to the job at hand. Here’s a list of the situations that need a little extra attention from a professional.

  • Major plumbing installations or remodels

If you’re revamping your home’s plumbing system, this is definitely a job for a professional. Major plumbing projects usually include tasks like:

  • Replacing all supply and drain pipes for new fixture layouts
  • Installing drainage lines and vents for showers, tubs, sinks
  • Ensuring proper pipe sizing and venting for new appliances
  • Acquiring proper permits and ensuring compliance with building codes

While some more minor jobs might be DIY-able, major things like pipework overhauls, sewer line replacements, and plumbing in a new bathroom need the knowledge and experience of a professional. 

What’s more, credible professionals will have the proper insurance in place to provide a financial safety net if things do go wrong. This applies even after the work has been completed!

All JustFix work is guaranteed for 12 months from the date of completion, giving you complete peace of mind that whatever we fix will stay that way.


  • Main water line repairs

While you can check your home’s water meter yourself, doing anything beyond this will require a professional. Repairing main water supply lines can involve things like:

  • Locating and excavating underground water service lines
  • Inspecting for leaks, tree root intrusions, corrosion
  • Ensuring no contamination enters the potable supply to your home

Sometimes, your region’s water authority might also need to intervene. You can find your local water and wastewater supplier online via the water.org.uk website.

  • Mould issues related to plumbing

If a patch of mould is caused by a leak in your home’s plumbing system, don’t try to fix it yourself. The mould could be a sign of a more serious or persistent leak somewhere in the pipework, so it’s always worth getting a professional to check it out.

Qualified plumbers can do all sorts of fancy things, including:

  • Using moisture meters to locate hidden leak sources
  • Repairing pipes and fixtures causing moisture problems
  • Remediating and replacing mould-damaged areas properly
  • Preventing cross-contamination from mould spores

Bonus tip! Plumbers are pretty nifty at fixing the cause of any mould, but they’re not always so good at clearing up the damage. Mould can leave nasty stains on your walls or ruin your wallpaper, so you might need to get in touch with a professional painter or decorator to put things right.


  • Water pressure issues

Okay, so this one is a bit of a grey area.

Sometimes, you can resolve water pressure problems yourself by re-pressurising your central heating system (pssst…we have a dedicated blog explaining exactly how to increase your boiler pressure).

If the problems persist, though, it’s best to call a professional plumber or boiler service engineer to come and take a look. They’ll be able to diagnose the root causes of high or low-pressure problems and, if needed, repair or replace pressure-relief valves (PRVs).


  • Commercial Plumbing

If the plumbing job in question is in a public or commercial space (a hospital, office building, or school, for example), it needs to be done by someone with the right qualifications.

Your average Joe off the street probably won’t have the skills or hands-on experience to:

  • Understand complex plumbing blueprints
  • Install arrays of toilets, sinks, and floor drains
  • Deal with high water volume demands
  • Ensure compliance with commercial plumbing codes
  • Have the required insurance in place for if anything goes wrong
  • Emergency plumbing jobs

When disaster strikes, it’s always best to get the pros in to put things right.

If your pipes burst in the middle of the night or you come home to a flooded basement, don’t try and take it on yourself! Contact a qualified plumber immediately to avoid things getting even more out of hand.

The benefits of hiring a professional plumber

While it can be tempting to take the DIY route to save money upfront, there are actually several benefits to swallowing your pride and calling in a pro…

  • You avoid costly mistakes: Even minor slip-ups on pipes could result in flooding and damage that may end up way more expensive to fix.
  • They get it done quickly and properly: A trained plumber has all the right tools and expertise to diagnose and repair issues efficiently.
  • Licenses and insurance protect you: Qualified plumbers carry insurance if any damages or injuries happen.
  • You maintain peace of mind: Handing it over to a professional gives you confidence that the job was done safely and in line with plumbing best practices.

How to tell when it’s time to contact a professional

But JustFix…how do I know when to call it a day and book a professional?!

Great question; we’re glad you asked.

Here are some things to look out for when deciding whether to contact a qualified plumber.

  • You have leaks that won’t stop: If you’ve tried fixing leaks already, but the damn things just won’t stop dripping, it’s time to call a plumber. Persistent leaks can lead to serious water damage if not resolved quickly.
  • You can’t unclog drains: If a good dose of Mr Muscle hasn’t done the trick, get a professional to come and take a look. The blockage might need more specialist equipment than you have at your disposal.
  • Suspected gas leaks: If you ever (and we mean EVER) think that there might be a gas leak, call a professional immediately. Telltale signs of a gas leak include an eggy smell and hissing noises. If you notice either of these, contact a Gas Safe registered JustFix engineer straight away.


Plumbing problems that you can fix yourself

Amateur handymen and women from across the land, this is your calling!

While some plumbing jobs need expert attention, others are perfectly fixable with a little bit of DIY know-how. 

Here’s a list of the types of plumbing problems you can usually sort yourself.

  • Unblocking drains: If blockages aren’t too bad, you can generally clear them using an off-the-shelf drain unblocker, hot water and a plunger.
  • Fixing dripping taps: A kitchen tap that won’t stop dripping is annoying, but they’re usually easy fixes. You’ll just need the right replacement parts (either washers or cartridges and O-rings, depending on your tap).
  • Unclogging toilets: It’s a dirty job, but somebody’s got to do it! Grab a plunger or toilet brush, and try to dislodge the clog with a bit of elbow grease.
  • Replacing showerheads: This is for the slightly more experienced DIY-ers out there, but it’s still a job you can do without professional help. You’ll need a new showerhead and some Teflon tape to wrap around the shower arm to create a water-tight seal.
  • Cleaning out sink U-bends: You can remove, clear, clean and reassemble your sink’s U-bend pipe relatively easily. Just make sure you have a bucket underneath the pipe before you make a start to catch any dirty water sitting inside!
  • Bleeding radiators: If your radiators feel cool at the top, you might need to bleed them (don’t worry, no radiators were harmed in the writing of this blog post). This basically means opening the bleed valve using a radiator key to let trapped air escape from inside the system. 
danger Just remember, bleeding your radiators can cause your central heating system to lose pressure, meaning hot water won’t flow to your taps at its usual rate. You might need to re-pressurise your boiler after bleeding your rads.


Book a professional plumber with JustFix

If your loo just won’t stop leaking or there’s water dripping from your ceiling, don’t panic; JustFix is only a few clicks away.

You can book a qualified plumber in minutes using our app. Simply tell us what your problem is and where you live, and we’ll connect you with a professional plumber in your area.

Find, book, and JustFix today. 

Seriously, it’s just that simple.

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