Chapter 10: Systems

These universal design features apply to the inner workings of a home that create comfort, ease of use, safety, and security.

Residential Universal Design Building Code, 2025 version. © The UD Project.

Section 10.1: Safety & Notifications

10.1.1 Smoke detectors with audible and visual alerts.

Smoke detectors should be present, with alert(s) that can be heard and seen throughout the home.

10.1.2 Carbon monoxide detectors with audible and visual alerts.

Carbon monoxide detectors should be present, with alert(s) that can be heard and seen throughout the home.

Audible and visual alerts are essential and can save lives. It's important to prepare for anyone living in or visiting a home. There are many reasons that people who can hear might miss an audible alert, e.g., listening to loud music with headphones (esp. noise canceling), so visual alerts aren't a specialized feature only beneficial for the deaf/hard-of-hearing.

10.1.3 All alert systems hardwired with battery backups.

Any alert should be hardwired into the home's power system, supplemented with battery backups. Alert systems plugged into power outlets are acceptable.

Hardwired alert systems will be more reliable than those only powered by batteries. Battery backups are essential for power outages.

Section 10.2: Electrical

10.2.1 Light switches ≤ 12 inches from doorways.

Switches that control lighting should require 12" (30cm) or less horizontal reach from any doorway between spaces.

10.2.2 Light switches aligned with door handles.

Switches that control lighting should be vertically aligned on walls with the height of the door handle.

Placing light switches within easy reach of doorways and at the same height as door handles creates predictability for locating them, especially when reaching into a room to turn the lights on/off from outside of the room.

If light switches are not conveniently located, chances are higher for lights to be left on when not needed, increasing energy costs.

10.2.3 Contrasting color between switch plates and walls.

The switch plate color must have a minimum contrast ratio of 3:1 against adjacent wall color(s).

This helps everyone easily locate switches, particularly some individuals with visual and/or cognitive impairments. Backlighting or built-in indicator lights can help, too, though lighting is not required.

The same 3.1 ratio is used in accessible web design. Check color contrast at WebAIM.

10.2.4 Light switches at both ends of hallways and pathways.

Light switches should be located at both ends of every hallway & pathway in easy-to-find locations.

If a pathway between Point A and Point B comprises more than one hallway or space, switches are only required to activate lighting in each space. This means that multiple lights will be turned on and off with multiple switches.

Whole-home smart lighting may be worth considering if it's important to illuminate multiple spaces at once, but this should not be a substitute for switches.

10.2.5 Switches within reach of any task area.

Any task area with dedicated task lighting should have a switch within easy reach to activate the lighting without leaving the area.

If switches are in areas with counters, ensure they're easy to reach while seated, typically in the range of 36-42″ (91-107cm) above the floor and not against the rear wall.

10.2.6 Switches near items they activate.

If a switch activates a specific item (e.g., a garbage disposal), it should be in an intuitive and logical location. If the item is used at a task area, the switch should be within reach of that area.

If locating a switch near an item it activates is not ideal, a label should indicate its purpose.

10.2.7 Switches wired to activate 50% of power outlets.

At least one light switch per room/space should activate 50% of power outlets, typically the top outlet on each duplex receptacle.

This increases a home's utility and convenience by allowing people to turn on/off plug-in lamps and other fixtures with the single operation of one switch in one location. This is also important for task areas that include task lighting, as many appliances or tools may be easier to turn on/off with a switch.

10.2.8 Switch type: rocker, touch, or motion sensor.

Switches should be able to be activated one-handed or with limited hand function. This typically includes rocker, touch, or motion sensor switch types.

Switches should not require someone to twist, pinch, or grab to activate. This is important for anyone with limited dexterity or grip strength.

Many switches now integrate with smart home technologies. While not required, this is a nice feature to consider.

10.2.9 Power outlets & other ports ≥ 16 inches from floor.

Power outlets and other ports (cable TV, wired networking, etc.) should be installed no less than 16" (41cm) from the floor, measured to the bottom edge of the cover plate.

Outlets and other ports should be at an easy-to-reach height, meaning that there's no requirement for someone to bend over significantly to access them. Between 16-20″ (41-51cm) from the floor to the bottom edge of a cover plate is ideal, but no higher than 48″ (122cm) to keep everything within a reasonable reach range if a lower install isn't possible in some locations.

10.2.10 Power outlets & other ports ≥ 20 inches from corners.

Power outlets and other ports should be installed no less than 20" (51cm) from any corner.

Ensure outlets and ports are at least 20″ (51cm) from any corner for easy access.

10.2.11 Power outlets near fronts of counters.

Where practical, some power outlets should be located near the fronts of the counters. Locations can be on the counter, an adjacent wall, or adjacent cabinetry.

In kitchens, bathrooms, or other spaces with counters, mounting outlets near the front of a counter will be helpful for items that are plugged/unplugged often. This increases usability by decreasing the need for reaching over the counter to access the rear wall, which can be especially difficult if appliances or other items are in the way.

10.2.12 Power outlets inside cabinetry.

Where practical, some power outlets should be located inside cabinetry, including inside of drawers.

In kitchens, bathrooms, or other spaces with counters, installing outlets inside cabinetry will be helpful for items (appliances, devices) that are rarely plugged/unplugged. This increases usability by removing the need to find an outlet each time something is used, decreasing the need for cord management, and increasing the overall tidiness of a space.

10.2.13 Breaker panel located on the main level.

The breaker panel should be located on the main level/floor.

The breaker panel should be in an easily accessed location on the main floor from the most regularly used areas without requiring an elevator ride.

If the breaker panel is outside, access should comply with Chapter 2: Entrance Routes.

This is only applicable to multi-story homes.

10.2.14 Breaker panel switches ≤ 48 inches from the floor.

Breaker panels should be installed so the topmost switch is no higher than 48" (122cm) from the floor.

The breaker panel switches should be reachable by everyone, regardless of height or whether accessing from a standing or seated position.

10.2.15 Breaker panel connection for backup or redundant power.

There should be a connection to the breaker panel with a transfer switch to install backup or redundant power options.

Generally speaking, power from the grid is pretty reliable. Sometimes, the power goes out, making backup or redundant power crucial, especially if used for medical needs. Operating climate control, lighting, an elevator, or any other electrical device at any time is ideal.

For multi-family housing (especially for rent) that doesn't provide space for someone to easily install a generator or solar, a backup/redundant power source for the entire building should be strongly considered.

Section 10.3: HVAC

10.3.1 Controls located between 36-48 inches from the floor.

HVAC controls should be located no less than 36" (91cm) from the floor and no more than 48" (122cm) from the floor.

Controls should be mounted for everyone to reach and see, especially if a user is seated or standing or short in stature.

10.3.2 Controls operable one-handed or with limited hand function.

HVAC controls need to be operable without twisting, pinching, or grasping any buttons or switches.

Operating controls one-handed (or with limited hand function) is essential. Touch controls are the easiest to use, though large dials can work if resistance is minimal. No control should require someone to perform twisting, pinching, or grabbing actions.

10.3.3 Filter access less than 48 inches from the floor.

HVAC filter access should be less than 48" (122cm) from the floor. This includes any latches to open a filter door.

Air filters should be within easy reach for easy maintenance by all. Individuals who use a wheelchair or other mobility device or are just of shorter stature should be able to change a filter without assistance. It's also safer for everyone if there's no design requirement to climb a ladder for access. If air filters are changed regularly, air quality will improve, making a home healthier.

Section 10.4: Other

10.4.1 Window controls & locks between 36-48 inches from the floor.

Window controls and locks should be located no less than 36" (91cm) from the floor and no more than 48" (122cm) from the floor.

Controls for windows and window coverings need to be easy to reach and manipulate. Controls (pull cords, wands, latches, etc.) must be accessible in a low, easy-to-reach location for people to use, whether seated or standing.

Any items that block access to controls to open/close windows and coverings will create difficulty for some people. Furniture is typically the culprit here.

Powered options to open and close windows and/or window coverings with a remote switch are acceptable. Still, smart window coverings that depend solely on a smartphone or smart speaker should be avoided.

10.4.2 Shut-off valves between 36-48 inches from the floor.

Shut-off valves for water and gas (if applicable) should be unobstructed and installed no less than 36" (91cm) from the floor and no more than 48" (122cm) from the floor.

Controls should be located for everyone to reach and see, especially if a user is seated or standing or short in stature.