Smoke and CO Alarms Need a Check Before the Tear-Off Starts

If your St. Charles house has smoke alarms on the ceilings of the upstairs hall and bedrooms, the roofing crew will be working above them for a day or two. The tear-off throws fine grit into the air, the hatch and ladders bring dust down the hall, and the hammering and open doors change the air around every sensor. An alarm that has been quiet for years can start chirping or sounding on the second morning of a job, and that is a poor way to start a week.

Town roofing

Alarm layouts in St. Charles County depend on when the house was built and how it was wired. Older homes in the blocks near the old downtown often have a mix: a battery unit in one bedroom, a hardwired unit in the hall, and sometimes a unit a previous owner added and never labeled. Homes in the newer subdivisions farther out in the county more often have hardwired alarms tied together on a shared circuit, so when one sounds, they all sound. Either way, walk the house before the crew arrives and write down each alarm, its room, and whether it runs on batteries or house wiring. That list takes about ten minutes, and it is the first thing a roofer will need to know if the attic route passes an alarm.

The attic hatch is the usual way into the attic, and in many houses it sits in a hallway, sometimes within a few feet of an alarm. Crews go up through that opening with ladders and material, and the tear-off sends debris down through the same opening. Photoelectric alarms sense smoke by how light scatters across a small chamber, so a fine film of dust inside that chamber can trigger them with no fire at all. Ionization alarms can also be affected by dust and by air movement. Neither type is a reason to skip the roof job. It is a reason to know where the alarms are before the first ladder goes up.

Do not wrap an alarm in plastic to keep it quiet during the work. A covered alarm cannot sense smoke, and the house is still occupied while the crew works, often with a kitchen in use and sometimes with a space heater or stove running. If the area under the hatch needs protecting from dust, the better step is to ask the crew to lay a drop cloth at the foot of the ladder and keep the hallway clear. The alarm stays exposed and working, and the dust path is shorter.

Roofing torches are a separate concern on some flat or low-slope sections, where a crew may heat a membrane to seal it. Torch work sends smoke and heat up and around the roof edge, and on a hot or still afternoon that smoke can drift toward the hallway below. Ask the crew whether any torch work is planned, and if it is, ask what they do to keep smoke away from the living space. The answer belongs in the written scope, not in a verbal promise on the driveway.

What it costs

A battery smoke alarm or carbon monoxide alarm is a small purchase at a hardware store or home center, and the cost is the unit itself. Many alarms carry a manufacture date printed on the back, and manufacturers commonly suggest replacing units about ten years after that date. A tear-off is a reasonable time to check the date on every unit, because the crew will disturb the house for a full day and you will be home for it anyway.

Replacing a hardwired unit is a different job. If the alarm is part of the house wiring, changing it is electrical work, and that bill goes to a licensed electrician rather than onto the roofing contract. Keep it out of the roof proposal so the proposal stays a roofing document. If an alarm starts chirping during the job because its backup battery is low, that is a battery swap you can do yourself in a few minutes, and it is not a roofing line item. Storms that knock out power can also cause hardwired alarms to switch to backup and start chirping, so keep spare batteries of the type your units take in the house during hail and wind season.

Budget the time too. A chirp that starts at nine in the morning can stop the crew for an hour while someone finds a step ladder and a battery. That time does not appear as a cost line on the roof bid, but it does shape the day, so plan for someone at home who can deal with an alarm while the crew works above.

What to ask

Ask the roofer these questions before the start date, and get the answers in writing:

• Which route does the crew use into the attic, and where does the hatch sit relative to the hallway and the alarms?
• Will any cord, work light, fan or generator run through a room that has an alarm, and at what time of day?
• Is any torch work planned on the flat or low-slope sections, and what keeps the smoke out of the living space?
• Who will be at the house when the hatch is open, and how will they reach you if an alarm sounds?
• Does the written scope say who handles the alarms, or does it leave them out entirely?

Write your alarm count on the same sheet as your other roof questions. Once you have the route and the answers in writing, you can decide whether a walk-through of the attic route is worth doing before the start date. Keys can talk through the route by phone at (314) 220-2333.