Half of drain callouts we go on could have been fixed by the customer in 20 minutes with basic tools. Here are the three things worth trying before you spend £80 on a plumber. Try them in order.

1. Plunger technique that actually works

Most people plunge wrong. The trick:

  • Buy a proper cup plunger (not the tiny toilet one) from any hardware shop. Screwfix or Toolstation £8.
  • Fill the sink halfway with hot water so the plunger has a proper seal
  • Block the overflow with a wet cloth (essential; without it you are just moving air)
  • Position the plunger over the plughole, pushing straight down
  • Sharp plunge, pull back, sharp plunge, pull back. Repeat 15 to 20 times
  • Try running the tap. If it drains freely, you are done

2. Hot water and washing soda

For grease and soap build-up in kitchen and bathroom drains:

  • Kettle of hot water (not boiling; boiling can crack ceramic and plastic joints)
  • Half a cup of washing soda crystals down the drain first
  • Follow with the hot water
  • Leave 30 minutes
  • Flush with cold water

Do NOT use caustic soda or "one-shot" drain unblockers routinely. They damage older pipework, especially cast iron and copper joints. One-off in an emergency only.

3. Drain rods for outdoor drains

If it is an outdoor drain (blocked gully, backed-up manhole), you need drain rods. Buy or hire from Screwfix (£25 to buy).

  • Lift the manhole cover nearest the blockage
  • Attach the plunger head to the first rod
  • Feed into the drain, screwing on additional rods as you go
  • Rotate CLOCKWISE ONLY (rods unscrew if you rotate anti-clockwise and you will lose the head down the drain)
  • Push and pull to break up the blockage
  • Flush with a hose or bucket of water after

When to give up and call

  • Water is backing up into other fixtures (sink drains into bath, toilet gurgles when kitchen sink drains) = main drain blockage
  • Manhole is completely full of sewage
  • Recurring blockages within days of clearing = structural issue (collapsed drain, root ingress)
  • Any smell of sewage inside the property

What a proper unblock costs

  • Single sink or toilet blockage: £80
  • Outside drain or main run: £180
  • Blockage plus CCTV survey (for recurring issues): £320

All prices include a 12-month no-fault warranty on the same blockage.

Preventing future blockages

  • Never pour oil or fat down the sink (biggest cause of kitchen drain blockages)
  • Hair guard on the shower drain
  • Nothing "flushable" down the toilet except pee, poo and paper (yes, wet wipes are the enemy)
  • Annual gutter cleaning stops rainwater joining the foul drain via overflows