Attention Homeowners and Property Managers

Since January 1, 2018, Maryland has updated and strengthened its smoke alarm regulations to improve fire safety in all residential dwellings. The goal of the law is simple, make sure every home has reliable, long-term smoke detection, regardless of age or construction type.

These changes have led to widespread replacement of outdated alarms with newer models that meet current safety standards. Depending on the jurisdiction and the building’s age, there may be additional local or code-specific requirements layered on top of the statewide law.

One of the most significant updates is the requirement for sealed 10-year battery smoke alarms in homes where battery-only units are permitted. Wireless interconnection options have also made it easier to bring older homes into compliance without running new wiring. In addition, there are now improved visual notification options to assist the hearing-impaired, an important enhancement for accessibility and life safety.

To help clarify what type of smoke alarm is required based on when your home was built, here is the most straightforward summary table we use with homeowners and property managers:

Why the Maryland Smoke Alarm Law Matters

The State Fire Marshal’s office pushed for this regulation after years of fire investigations showed the same recurring issue: non-working or missing smoke alarms in older homes. Fires move faster today than they did 20 or 30 years ago, partly due to modern building materials and furnishings. That means seconds matter, and an early warning system is the difference between safe escape and tragedy.

By requiring sealed long-life alarms, Maryland ensures:

• Smoke alarms stay powered continuously for 10+ years
• Devices are not disabled or forgotten after battery removal
• Homeowners receive a clear replacement cue when the alarm reaches end-of-life
• Alarms are placed in proper code-compliant locations

In addition, wireless interconnection technology has made it much easier to bring older homes up to modern safety standards. In newer homes, hardwired interconnected alarms are still required — but in older homes without existing wiring, wireless interconnectable models can now meet code without cutting walls or running new cable.

All Maryland residential dwelling units are covered by the 2018 law, including:

• Single-family homes
• Townhomes
• Condominiums
• Rental units and multi-family properties
• Manufactured homes
• Basement apartments / in-law suites

The type of smoke alarm required depends largely on when the home was built and whether a wired alarm system already exists. If the home already has a hardwired interconnected system, it must remain hardwired when replaced. You cannot downgrade to battery-only just because it is cheaper or easier. On the other hand, if a home was never wired for smoke alarms to begin with, a 10-year sealed lithium alarm is compliant in most cases.

When Are You Required to Upgrade or Replace?

Under Maryland’s updated regulations, you must upgrade your smoke alarms if any of the following apply:

• Your current alarm is more than 10 years old
• The alarm fails testing or chirps and is non-functional
• You are renovating, remodeling, or adding square footage under a building permit
• You are selling, leasing, or re-renting a property
• You are replacing a battery-only unit that no longer meets code

The law is structured so that upgrades happen gradually as older alarms reach their end-of-life. This ensures homes move toward full compliance without forcing every homeowner to replace all alarms immediately at once.

Improvements for Accessibility and Life Safety

Another major benefit of the 2018 update is improved protection for people with hearing impairments or accessibility needs. Modern systems now integrate:

• Strobe signal alarms for the hearing impaired
• Bed-shaker vibration units for nighttime alerting
• Combination voice + tone warnings for clarity
• Interconnected triggering so every occupant receives the same alert

These updates help ensure equitable protection, giving all residents adequate time to evacuate.

Local Jurisdictions May Require More

Maryland’s law sets the statewide baseline, but several counties — including Baltimore County, Baltimore City, Montgomery County, and Prince George’s County — have additional placement or interconnection requirements based on local adoption of NFPA 72.

For example:

• Newer construction typically requires alarms inside every sleeping room, not just in hallways.
• Some jurisdictions require hardwired + battery backup alarms even for major interior renovations.
• In rental properties, the owner is responsible for ensuring alarms remain code-compliant between tenants.

When in doubt, it’s smart to have a licensed electrician verify both placement and power source requirements.