Wiring in Walls: Best Practices for Installing Cable in Chases

Why Concealed Wiring in Wall Chases Matters

In the United States, concealed (hidden) wiring is a common approach for creating neat, efficient electrical installations that meet both National Electrical Code (NEC) requirements and modern design standards. One popular method involves routing cables inside wall chases—small channels or grooves cut into a masonry, concrete, or block wall.

At safsale.com, we understand that safe, high-quality materials and proper planning are vital to any concealed wiring project in the USA. Below, we outline best practices to help you achieve reliable, code-compliant results.

Methods of Concealed Wiring in the USA

Several options exist for placing wiring behind walls so it remains invisible:

1. In a Wall Chase (Groove or Channel)

2. Over the Wall, Covered by Plaster or Stucco (no chase required if plaster thickness allows)

3. Behind Drywall or Gypsum Board

   • Mounted on the wall surface, then covered with drywall
   • Inside a hollow partition built with drywall on both sides

Additionally, some US homeowners use flexible conduits or rigid pipes (metal or PVC) within the chase for extra protection—especially important in wood-framed homes, where local codes may be stricter about fire safety.

Installing Cable in a Wall Chase

A wall chase (also called a “chase” or “groove”) is a carved-out channel in concrete, masonry, or brick. The NEC and local building regulations typically require the chase to:

1. Fit the Cable’s Dimensions – Provide enough space for the cable (or conduit) without deforming insulation.
2. Preserve Structural Integrity – Avoid excessive cutting that weakens load-bearing walls or columns.

2.1 Chase Dimensions

• Many contractors suggest keeping the groove to around 1 x 1 inch (2.5 x 2.5 cm).
• Never cut into rebar or major structural supports, especially in multi-story or load-bearing walls.

2.2 Minimum Distances

To reduce future hazards or damage, these guidelines are often followed in the USA:

• Keep wiring at least 2 inches (50 mm) away from water or gas pipes.
• Maintain 6 to 8 inches (15–20 cm) of clearance from ceiling corners.
• Leave 4 inches (10 cm) from vertical edges at door or window frames.

Such spacing avoids potential drilling damage and makes future repairs easier.

Laying Out Your Wiring Routes

Straight runs, either horizontal or vertical, are standard practice in the United States. Diagonal routing is generally discouraged because it complicates future renovations and can lead to accidental cable punctures.

1. Identify Receptacle and Switch Locations – Mark these first, then plan horizontal or vertical lines.
2. Document or Photograph the Layout – Noting distances from corners, floors, or doors helps anyone drilling into the walls later.

Cutting the Chase: Tools and Tips

Chase cutting can be loud, dusty, and time-consuming, but several methods exist:

• Dedicated Wall Chaser: Specialized saw with dust collection, providing clean parallel cuts.
• Angle Grinder (“Saw with Diamond Blade”): Make two cuts and remove the middle with a hammer drill or chisel.
• Hammer Drill Alone: More labor-intensive, but possible for smaller projects.

Where cables must change direction, remember to maintain a minimum bending radius—often 6–10 times the cable’s outer diameter.

Alternative: No-Chase Installations

If you plan to apply a thick plaster or stucco layer (1–1.25 inches / 2–3 cm), you may skip cutting chases by simply attaching the cable to the wall and letting plaster cover it. However, you must firmly secure the cable so it doesn’t move while the plaster sets.

Cable Types and Fire Safety

For hidden wiring in non-combustible masonry or concrete walls, standard double-insulated (PVC) cables are commonly used in the USA. A flat profile cable (like Type NM-B “Romex”) often fits neatly into shallow chases.

5.1 Popular “Classic” Choice: VVG or NM-B

Many US electricians and DIYers rely on Type NM-B cable (commonly referred to as “Romex”), which is:

• Easy to handle
• Rated for concealed use behind walls
• Generally meets NEC standards for residential circuits

Some installers recommend low-smoke, flame-retardant or LS-rated cables for extra fire protection, but in fully enclosed masonry walls, this is often optional. If you want to exceed minimum code requirements, safsale.com carries a range of high-grade, fire-resistant cables that may suit your project.

5.2 Conductor Size (AWG)

Choose wire gauge based on the circuit load:

• 14 AWG for up to 15A circuits (lights, general outlets)
• 12 AWG for up to 20A circuits (kitchen, laundry, bathroom outlets)
• 10 AWG or larger for heavy appliances (AC units, dryers, ovens)

For a comprehensive overview of US wire gauges and NEC ampacity tables, visit safsale.com or consult a licensed electrician.

Additional Considerations

• Don’t Overstuff the Chase – Overcrowded wires risk overheating. Maintain some airspace or use a conduit sized appropriately for the cable bundle.
• Secure All Connections in Accessible Boxes – The NEC prohibits hidden splices or junctions outside recognized enclosures.
• Use GFCI and AFCI Protection Where Required – Kitchens, bathrooms, and living areas typically need ground fault or arc fault protection as per code.
• Preserve Structural Integrity – For large or load-bearing walls, consult a structural engineer if wide or deep chases are needed.

Why Choose SafSale.com for Your Wiring Needs?

At safsale.com, we understand the unique challenges of concealed wiring in the United States. We offer:

• UL-listed cables in various gauges and fire-retardant ratings
• Conduits, fittings, and accessories to simplify chase installations
• Expert advice on NEC compliance, product selection, and best practices
• Fast shipping across the USA for timely deliveries to your project site

Upgrade your wiring system with confidence—shop at safsale.com today.

Conclusion: Safe, Efficient Chase Wiring in US Homes

Routing electrical cables in wall chases is a popular and effective way to hide wiring behind masonry or block surfaces. By following NEC-compliant guidelines—maintaining safe distances, using correct cable gauges, and ensuring structural integrity—you can achieve a professional finish without compromising on safety.

Remember:

• Always plan your cable routes carefully and avoid diagonal runs.
• Document the layout to prevent accidental damage during future remodeling.
• Use appropriate tools (wall chaser, grinder, or hammer drill) and maintain minimum cable bend radii.
• Select the right cable (NM-B, MC, or specialty LS-rated) based on code requirements and the environment.

When in doubt, consult a licensed electrician and rely on safsale.com for high-quality electrical products, from cables to conduits. Together, we’ll help you build a safe, reliable, and aesthetically pleasing concealed wiring system in any US home.