False Economy: Five Blunt Questions That Tell You When Patching Becomes Pointless

A repair bill is the easiest bill to agree to. It is small, it is urgent, and the van is already outside. Nothing about that moment encourages clear thinking. But repairs have a habit of arriving in instalments, and the instalments add up quietly until the day you realise you have spent two thirds of a replacement on keeping the old thing alive.

This is not an argument for replacing everything that creaks. Far from it. Well-maintained kit lasts decades, and a six-year-old boiler with a failed pump deserves a pump, not a skip. What follows is a filter, not a verdict: five questions to run through before you authorise anything with a three-figure price tag.

Question one: how old is it, honestly?

Age is only useful when you compare it to the expected service life of the thing in question. A useful starting set for a typical UK home:

• Combi boiler: 10 to 15 years, longer if it has been serviced annually and the water is not hard.
• Sealed double-glazed units: 15 to 20 years before the desiccant gives up and the pane mists.
• Concrete roof tiles: 50 years and beyond, though mortar, flashings and fixings fail far sooner.
• Felt flat roof: 10 to 15 years. GRP or single-ply, 20 to 25.
• Washing machine or dishwasher: 7 to 10 years of family use.
• Fridge freezer: 10 to 15 years.
• Consumer unit and wiring: 25 to 40 years, depending on the installation.

If the item is past its span and the fault is in a core component rather than a consumable, you are no longer maintaining it. You are buying time, and time has a price. Ask yourself what that price is per year of extra life, then ask whether you would pay it again.

Question two: is anything about this unsafe?

Safety is a veto, not a vote. It overrides every other consideration on this list.

Anything involving gas, a flue, solid fuel, or the fixed wiring of the house moves out of the DIY column and into the hands of someone registered to do the work. Gas Safe registration can be checked in a couple of minutes, and it is worth those minutes every single time. A repair that keeps a dangerous appliance limping along is not a bargain, whatever the invoice says.

Older fuse boxes with rewireable fuses, a boiler that has been boxed in with no ventilation, a chimney that has never been swept: these are not maintenance items to defer. They are the reason to stop reading and start ringing.

Question three: how often have you paid for this?

One repair in five years is normal wear. The third visit in eighteen months is a pattern, and patterns are what you are really costing up.

Do the arithmetic properly. Add the call-out charges, the parts, the afternoons off work, and the days spent waiting in. A fairly ordinary boiler fault in 2026 might be £180 for the visit plus £220 for the part. Do that twice in two years and you have spent £800 on a boiler that is now twelve years old and still out of warranty. Set that against roughly £2,600 to £4,500 for a like-for-like combi swap, and the sums start making their own argument.

The reverse also holds. A five-year-old machine with a £140 repair bill has years of life left in it. Frequency tells you about reliability, not age, and reliability is what actually keeps you warm.

Question four: what is the energy penalty?

Older appliances waste money quietly, every single day. That is different from a broken appliance, which wastes money loudly and once.

An old non-condensing boiler might run at around 70% efficiency against 92% or better for a modern condensing unit. Single-glazed windows leak heat that you have already paid for. A fridge from 2010 costs more to run than one from this decade. None of these figures should be treated as a guaranteed payback, because the numbers depend on your tariff, your usage and your house. Be sceptical of anyone who promises a replacement will pay for itself in three years. Comfort, reliability and a warranty are legitimate benefits too, and worth counting.

Where the energy penalty is large and the machine is already failing, the two factors compound. Where the machine is efficient and simply old, they do not.

Question five: what does failure take with it?

Some failures are contained. A dead washing machine is an inconvenience. Others spread, and water and heat are the two great spreaders in any house.

A failed gutter joint soaks a fascia, then the rafter ends behind it, then finds its way into a ceiling. A leaking valve under a bath ruins flooring and a kitchen ceiling. A cracked seal around a shower tray is a cheap fix now and a joist replacement later.

Ask what the consequence of a full failure would be, not what the consequence of failing to repair it today would be. If the answer involves structural timber, ceilings or electrics, the calculation has changed in favour of spending more now.

The old rule of thumb that you should replace when the repair exceeds half the cost of new is a rough guide, not gospel. It ignores safety, frequency and knock-on damage entirely. Use it as a backstop after the five questions, never instead of them.

The rule that sits above all five

Get two written quotes. Not verbal estimates, not a figure scribbled on a pad, not a phone call that ends with 'we will sort you out'.

A proper quote should itemise parts and labour, state whether VAT is included, say how long the guarantee runs and what it covers, and confirm whether the price is fixed or subject to what they find once the panels come off. Ask directly what happens if they discover something worse in there. The answer tells you a lot about the firm.

Compare like with like. A quote for a boiler swap that excludes a power flush and a magnetic filter is not cheaper than one that includes them. It is just a different job.

Then write down what you decided and why. In three years, when the same appliance starts making the same noise, that note will save you from repeating the whole exercise from memory. And if the answer is repair, that is a perfectly good outcome. This test exists to protect your wallet from both directions.