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Chapter 05Calendar · Practical note

The monthly walk

Quick answer

Once a month, on the same day, walk the house in one loop. Press test on every smoke alarm and CO alarm (NFPA says at least once a month). Slide out the HVAC filter and look at it (ENERGY STAR says inspect, clean or change it monthly). Read the water meter and write the number down. Look under each sink for water on the outside of pipe fittings and faucet parts (EPA). Then write one line on the log: the date, what you checked and anything new.

Source: NFPA, installing and maintaining smoke alarms, checked October 15, 2026; NFPA, carbon monoxide safety, checked October 15, 2026; ENERGY STAR maintenance checklist, checked October 15, 2026; EPA WaterSense, Fix a Leak Week, checked October 15, 2026.

Example8 dated jobs a yearCold region, plus 2 monthly checks

The walk

Pick one day of the month and keep it. Start at the top floor and finish where the water meter is, so the loop ends near the pen and the log.

  • Press test on every smoke alarm and every CO alarm. NFPA says to test both at least once a month.
  • Slide out the HVAC filter and look at it. ENERGY STAR says to inspect, clean or change the filter once a month in a central air conditioner, furnace or heat pump.
  • Read the water meter and write down every number on it.
  • Open the cabinet under each sink and look for water on the outside of the pipe fittings and around the faucet parts. EPA says faucet gaskets and pipe fittings are where surface leaks show.
  • Pick one toilet this month for the food coloring test (more on that below).

Source: NFPA, installing and maintaining smoke alarms, checked October 15, 2026; NFPA, carbon monoxide safety, checked October 15, 2026; ENERGY STAR maintenance checklist, checked October 15, 2026; NYC DEP, How to Read Your Water Meter, checked October 15, 2026; EPA WaterSense, Fix a Leak Week, checked October 15, 2026.

The monthly walk, one loop Five stops in the same order every month: press test on every smoke and CO alarm, slide out the HVAC filter and look, read the water meter and write the number, look under each sink for water on the outside of fittings, one toilet a month gets the food coloring test. Then write one line with the date, the meter number and anything new. The monthly walk: one loop, same day each month 1Press test on every smoke and CO alarmWrite down any alarm that stays quiet. 2Slide out the HVAC filter and lookNew one in? Date on the frame, size on the log. 3Read the water meter, every digitThis month minus last month is the month's use. 4Under each sink: water on the fittings?Look and touch. Found some? Date, photo, book the fix. 5One toilet a month: the food coloring testDrops in the tank, wait 10 minutes, look in the bowl. Then write one line: the date, the meter number and anything new.
Fig. 1One loop, five stops, the same order every month. The log line comes last.

Stop 1: the alarms

Press and hold the test button on each smoke alarm until it sounds, then do the same on each CO alarm. NFPA's rule for both is at least once a month. If one stays quiet, write down which one and follow the maker's instructions, or tell the landlord if you rent.

Source: NFPA, installing and maintaining smoke alarms, checked October 15, 2026; NFPA, carbon monoxide safety, checked October 15, 2026.

The smoke alarm record keeps the full alarm list, with each alarm's location and replace-by year. The monthly walk only needs a tick and the date.

Stop 2: the filter

Slide the filter out and hold it up to the light. ENERGY STAR's rule is a monthly look: inspect, clean or change. If you put a new one in, write the date on its frame and the size on the log. If the shelf of spares is empty, add filters to the shopping list that day.

Source: ENERGY STAR maintenance checklist, checked October 15, 2026.

Stop 3: the water meter

A water meter keeps a running total, like a car odometer, and isn't reset each month. So this month's number minus last month's is what the house used. Write down every digit, including any fixed or painted zeros at the end. Many meters read in cubic feet; one cubic foot is 7.48 gallons.

Source: NYC DEP, How to Read Your Water Meter, checked October 15, 2026; Kentucky PSC, A Consumer's Guide to Reading Electric & Gas Meters, checked October 10, 2026.

Worked example: September 15 reads 4,812 and October 15 reads 5,330. The month used 518 cubic feet, and 518 times 7.48 is about 3,875 gallons.

Monthly water meter log Three rows of a water meter log in cubic feet. September 15 reads 4,812. October 15 reads 5,330, used 518 cubic feet. 518 times 7.48 is about 3,875 gallons. November 15 is still blank. A big jump with no reason is the month to do the two-hour meter check. Water meter log (meter reads in cubic feet) DATEREADINGUSED THIS MONTH Sep 154,812first line: no use yet Oct 155,330518 cu ft Nov 15 5,330 - 4,812 = 518 cu ft. 518 x 7.48 gal = about 3,875 gallons this month. A big jump with no reason? That's the month for the two-hour meter check.
Fig. 2The meter never resets. This month's number minus last month's is the month's use.

A single month's number tells you little; a year of them shows what is normal for your house. EPA's rough line: if a family of four uses more than 12,000 gallons in a colder month such as January or February, there could be serious leaks.

Source: EPA WaterSense, Fix a Leak Week, checked October 15, 2026.

A jump you can't explain

If the month's use jumps and nothing changed (no guests, no new garden), do EPA's meter check: read the meter, use no water for two hours, read it again. If the number moved at all, there is probably a leak. Write both readings down and call a plumber, or the landlord if you rent.

Source: EPA WaterSense, Fix a Leak Week, checked October 15, 2026.

Stop 4: under the sinks

Open each sink cabinet: kitchen, bathrooms, laundry. Look and touch. You're looking for water on the outside of the pipe fittings and around the faucet, which EPA calls surface leaks. A dry paper towel laid on the cabinet floor makes next month's look faster, since any new drip marks it.

Source: EPA WaterSense, Fix a Leak Week, checked October 15, 2026.

Found something? Write the sink and the date on the log, take a photo, and book the fix with a plumber or the landlord. Repairs are a separate job.

Stop 5: one toilet a month

  1. Color the tank

    Put a few drops of food coloring in the toilet tank (not the bowl).

  2. Wait ten minutes

    Don't flush. Finish the rest of the walk while you wait.

  3. Look in the bowl

    If color shows in the bowl, the toilet leaks. Write it on the log.

  4. Flush right after

    Flush when you're done so the coloring doesn't stain the tank.

One toilet a month keeps the walk short. In a house with three toilets, each one gets its turn four times a year.

Let the tool do the arithmeticHome maintenance calendarThe home maintenance calendar puts the monthly walk on a dated year sheet next to the seasonal jobs, so the March and November lists land on the same page.Example: 8 dated jobs a year (Cold region, plus 2 monthly checks)Open the tool
Start at the top of the house and finish at the meter, where the log lives.

Write one line

Write the line before you put the pen down: date, alarms ticked, filter looked at (or changed, with the size), meter number, the month's use, which toilet got the test, and anything new you saw. A blank "anything new" is a good month. Twelve lines make a year you can hand to a plumber, a landlord or the next owner.

Checklist to print

Same day each month, one loop:

  • Press test on every smoke alarm
  • Press test on every CO alarm
  • Write down any alarm that stayed quiet
  • Slide out the HVAC filter and look
  • New filter: date on the frame
  • Read the water meter, every digit
  • This month minus last month = use
  • Under each sink: water on fittings?
  • One toilet: food coloring, 10 minutes
  • Write the date, number and anything new

Open the printable checklist

The monthly walk

Tips and tricks

  • Tip 01

    Tie it to a date you already have

    The day rent is due, the day a bill arrives, the first Saturday. Any fixed day works better than "sometime this month".

  • Tip 02

    Keep the log where the meter is

    A clipboard and pencil near the meter or the filter means the line gets written before you walk away.

  • Tip 03

    Photo the meter

    A phone photo of the meter face with the date on it backs up the number you wrote, and settles any doubt about a digit.

  • Tip 04

    Renting? Know who fixes what

    The walk works the same in a rental. The difference is the last step: anything you find goes to the landlord, in writing, with the date.

What we would do

Same day, same loop, one line

Start this month. Pick the day, walk top floor to meter, and write the first line even if nothing is new. The second month's reading gives you the first month's use.

Questions

What should I check in my house every month?

The four monthly rules from public sources: test each smoke and CO alarm (NFPA), look at the HVAC filter (ENERGY STAR), read the water meter so you can spot a jump, and look under the sinks for surface leaks (EPA). Write one line when you're done.

Source: NFPA, installing and maintaining smoke alarms, checked October 15, 2026; NFPA, carbon monoxide safety, checked October 15, 2026; ENERGY STAR maintenance checklist, checked October 15, 2026; EPA WaterSense, Fix a Leak Week, checked October 15, 2026.

How often should I test my smoke alarms?

At least once a month, using the test button, per NFPA. CO alarms get the same monthly test.

Source: NFPA, installing and maintaining smoke alarms, checked October 15, 2026; NFPA, carbon monoxide safety, checked October 15, 2026.

How often should I change the air filter?

ENERGY STAR says to inspect, clean or change it once a month. Looking monthly tells you whether this is the month to change it.

Source: ENERGY STAR maintenance checklist, checked October 15, 2026.

How do I turn my water meter reading into gallons?

Subtract last month's reading from this month's. If the meter reads in cubic feet, multiply by 7.48 to get gallons, per NYC DEP. If it reads in gallons, the difference is already gallons.

Source: NYC DEP, How to Read Your Water Meter, checked October 15, 2026.

How do I know if my toilet is leaking?

EPA's test: a few drops of food coloring in the tank, wait 10 minutes without flushing, and if color shows in the bowl, it leaks. Flush afterward so the tank doesn't stain.

Source: EPA WaterSense, Fix a Leak Week, checked October 15, 2026.

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