Most maintenance advice online is either a vague seasonal checklist or a manufacturer telling you to service something twice as often as it needs. What follows is the practical middle: how often things genuinely need attention in a normal house.
Two rules before the table. Your own manual always wins, because a specific model may differ. And a job you have never done on a twenty year old system may need doing sooner than the interval suggests, because the interval assumes it was kept up.
Heating, cooling and water
The systems where neglect is most expensive, and where a missed service usually shows up in the coldest or hottest week of the year.
Boiler or furnace service
- Interval
- Annually
- Why this interval
- Required by most warranties, and the check that catches unsafe combustion
Replace HVAC filter
- Interval
- 1 to 3 months
- Why this interval
- Depends on pets, dust and whether anyone in the house has allergies
Flush water heater
- Interval
- Annually
- Why this interval
- Sediment builds from the first year and quietly destroys efficiency
Water heater anode rod check
- Interval
- Every 3 to 5 years
- Why this interval
- The single cheapest way to extend a tank's life
Bleed radiators
- Interval
- Annually, before heating season
- Why this interval
- Trapped air means cold tops and a system working harder than it should
Service air conditioning
- Interval
- Annually, before summer
- Why this interval
- A failure in August takes far longer to fix than one in April
Check and clean condensate drain
- Interval
- Annually
- Why this interval
- A blocked drain is a common and avoidable cause of water damage
| Job | Interval | Why this interval |
|---|---|---|
| Boiler or furnace service | Annually | Required by most warranties, and the check that catches unsafe combustion |
| Replace HVAC filter | 1 to 3 months | Depends on pets, dust and whether anyone in the house has allergies |
| Flush water heater | Annually | Sediment builds from the first year and quietly destroys efficiency |
| Water heater anode rod check | Every 3 to 5 years | The single cheapest way to extend a tank's life |
| Bleed radiators | Annually, before heating season | Trapped air means cold tops and a system working harder than it should |
| Service air conditioning | Annually, before summer | A failure in August takes far longer to fix than one in April |
| Check and clean condensate drain | Annually | A blocked drain is a common and avoidable cause of water damage |
Structure, water ingress and safety
Cheap to do, expensive to skip. Nearly all water damage in homes starts with something on this list.
Clear gutters and downpipes
- Interval
- Twice a year
- Why this interval
- Autumn after leaf fall, and spring after winter debris
Inspect roof and flashing
- Interval
- Annually
- Why this interval
- Most roof failures start at a joint, not in the middle of a slope
Reseal grout and caulk
- Interval
- 1 to 2 years
- Why this interval
- Failed sealant lets water behind tile, where it is invisible for months
Test smoke and CO alarms
- Interval
- Monthly
- Why this interval
- The only job here where the cost of skipping is not measured in money
Replace smoke alarm units
- Interval
- Every 10 years
- Why this interval
- Sensors degrade whether or not the battery is fine
Check for leaks under sinks
- Interval
- Twice a year
- Why this interval
- A slow leak rots a cabinet base long before anyone notices
| Job | Interval | Why this interval |
|---|---|---|
| Clear gutters and downpipes | Twice a year | Autumn after leaf fall, and spring after winter debris |
| Inspect roof and flashing | Annually | Most roof failures start at a joint, not in the middle of a slope |
| Reseal grout and caulk | 1 to 2 years | Failed sealant lets water behind tile, where it is invisible for months |
| Test smoke and CO alarms | Monthly | The only job here where the cost of skipping is not measured in money |
| Replace smoke alarm units | Every 10 years | Sensors degrade whether or not the battery is fine |
| Check for leaks under sinks | Twice a year | A slow leak rots a cabinet base long before anyone notices |
The jobs that belong to a month, not an interval
About a third of outdoor maintenance is seasonal rather than periodic. Winterising outdoor taps belongs before the first freeze, not three hundred and sixty five days after you happened to write it down. Blowing out an irrigation system belongs in autumn regardless of when it was last done.
This is why generic reminder apps get ignored. Anything that tells you to winterise in July has told you something useless, and after the second or third useless reminder people stop reading them entirely.
Seasonal jobs, by when they belong
4 things to do
Ticks are for this visit only. Nothing here is saved anywhere.
Start from the last done date, not from today
The most common mistake when setting up any maintenance schedule is to start every interval from the day you wrote the list. That schedules a boiler service twelve months from an arbitrary Tuesday rather than twelve months from the last actual service.
If you know roughly when something was last done, use that. If you genuinely do not know, treat it as due, because for most of this list an unnecessary check costs an hour and a missed one costs considerably more. There is more on which of these bite hardest in the maintenance you skip that costs the most.