Chases in Construction: Purpose, Types, and Best Practices
In the world of construction and architectural design, chases are an often-overlooked yet vital component. Whether you’re building a residential home, a commercial complex, or an industrial facility, chases in construction allow for the integration of mechanical, plumbing, and electrical systems in a concealed, functional, and accessible manner.
This detailed guide explores what chases are in construction, their different types, why they are important, how they are built, and the best practices to ensure code compliance and functionality.
🏗️ What Is a Chase in Construction?
A chase in construction refers to a dedicated recessed space or passage built into a wall, floor, or ceiling to house mechanical, electrical, or plumbing (MEP) systems. Chases allow builders and contractors to hide pipes, ductwork, and wiring while maintaining access for maintenance or upgrades.
Chases are essential for preserving a building’s aesthetic appeal while still enabling functionality and compliance with local building codes.
🧱 Purpose of Chases in Buildings
Chases serve multiple functions across different types of construction:
1. Concealment
- Keeps utilities such as water pipes, HVAC ducts, and electrical wiring hidden from view.
- Preserves the interior design and layout of living or commercial spaces.
2. Accessibility
- Allows service personnel to access and maintain utility lines through strategically placed panels or openings.
3. Organization
- Helps organize MEP systems by routing them through planned, enclosed paths.
4. Safety
- Prevents direct human contact with live wires or hot/cold pipes.
- Contains fire-retardant materials to prevent fire spread across floors or rooms.
🔧 Common Types of Chases in Construction
1. Pipe Chase
- Designed specifically to house water, gas, or waste pipes.
- Often vertical, running between floors in multi-story buildings.
2. Duct Chase
- Created to route HVAC ductwork discreetly.
- Typically vertical shafts or horizontal spaces above ceilings.
3. Electrical Chase
- Used to run conduits and cabling for lighting, outlets, and telecommunications.
- Helps avoid external cable trays or surface-mounted wiring.
4. Shaft or Utility Chase
- Larger vertical spaces running between multiple floors.
- May carry a combination of plumbing, electrical, and mechanical systems.
5. Floor or Ceiling Chase
- Horizontal chases embedded within slab floors or suspended ceilings.
- Frequently used in commercial buildings and hospitals.
📐 Chase Design Considerations
Proper chase design is essential to ensure functionality, compliance, and ease of maintenance. Several factors must be addressed during the planning and construction phase.
| Design Factor | Best Practice |
|---|---|
| Size of Chase | Should be sized to accommodate current and potential future utility requirements. |
| Clearance Space | Adequate spacing should be maintained between different types of services inside the chase. |
| Accessibility | Access panels should be installed for inspection and maintenance without damaging finishes. |
| Fire Rating | Chases passing through fire-rated assemblies should include firestop systems. |
| Noise Insulation | Soundproofing is recommended when running water or HVAC through walls adjacent to living areas. |
🔥 Fire and Acoustic Requirements
Chases that connect multiple floors or rooms must meet fire-resistance requirements as per local building codes. This includes:
- Using fire-rated drywall or shaft liners inside the chase.
- Installing firestopping sealants around pipe or duct penetrations.
- Insulating for sound attenuation, especially in multi-family or hotel buildings.
🧰 Construction Methods for Chases
Chases can be framed during initial construction or added during remodeling. Here’s a general workflow for creating a chase:
- Planning & Coordination: Architects and MEP engineers determine chase location and size based on service needs.
- Framing: Wood or metal studs are used to construct the chase structure.
- Utility Installation: Pipes, wires, and ducts are installed in the framed space.
- Enclosure: Chase is sealed with drywall or fire-rated panels, with optional access doors.
- Firestopping & Insulation: Required materials are added to meet safety standards.
🏢 Applications of Chases in Construction
| Building Type | Typical Use of Chases |
|---|---|
| Residential Homes | Conceal plumbing and electrical systems in kitchens and baths |
| Commercial Buildings | Run HVAC, IT cabling, and fire sprinkler systems |
| Hospitals | Use vertical chases for oxygen lines and electrical systems |
| Hotels | Chases behind walls in each room for maintenance efficiency |
| High-Rise Buildings | Multi-floor utility risers in central shafts |
🧠 Benefits of Using Chases in Building Design
| Benefit | Explanation |
|---|---|
| Cleaner Aesthetics | Hides mechanical and electrical systems from public view |
| Improved Maintenance | Allows technicians to access utilities without damaging walls or ceilings |
| Design Flexibility | Enables centralized service lines with minimal disruption to layout |
| Future-Proofing | Makes future upgrades or expansions easier and less invasive |
| Code Compliance | Helps meet mechanical and fire code requirements through organized routing |
⚠️ Common Mistakes to Avoid with Chases
- Inadequate Sizing: Leads to overcrowding of utilities, difficult maintenance, or code violations.
- Poor Coordination Between Trades: Causes conflicts between plumbing, electrical, and HVAC systems.
- Skipping Firestopping: Increases fire risk and fails inspections.
- No Access Panels: Makes maintenance costly and invasive.
- Improper Soundproofing: Allows noise from pipes or ducts to affect adjacent rooms.
📋 Chase vs Shaft vs Cavity Wall
| Feature | Chase | Shaft | Cavity Wall |
|---|---|---|---|
| Purpose | Conceals MEP services within walls/floors | Vertical passage for elevators, utilities, HVAC | Space between two walls for insulation or moisture control |
| Size | Smaller, limited to MEP systems | Larger, spans multiple floors | Narrow space (usually 2–6 inches) |
| Accessibility | Usually via small panels | Often accessible via mechanical rooms | Not intended for access |
❓ FAQs: Chases in Construction
1. What is a chase wall in construction?
A chase wall is a specially constructed wall with an internal cavity large enough to run MEP systems such as plumbing pipes or ductwork.
2. Are chases fire-rated?
They can be. Chases that pass through fire-rated assemblies must be constructed with fire-resistant materials and sealed with approved firestopping.
3. How wide should a chase be?
Chase width depends on the number and type of utilities being housed. A minimum of 12 to 18 inches is common, though more space may be needed for combined services.
4. Can multiple utilities run in the same chase?
Yes, but separation guidelines must be followed, especially for electrical systems to prevent interference and maintain safety.
5. Are chases only used in commercial buildings?
No, chases are used in both residential and commercial structures, particularly in bathrooms, kitchens, utility rooms, and HVAC zones.
6. Do chases add to construction costs?
There is a small upfront cost, but chases save money long-term by enabling easier maintenance and reducing damage during upgrades or repairs.
7. How are chases different from utility rooms?
Utility rooms are dedicated spaces, while chases are hidden, embedded zones within walls or floors designed for routing utilities.
8. Is insulation required inside chases?
Yes, in certain cases. Thermal and acoustic insulation is often added, especially if the chase is near living spaces or needs to comply with energy codes.
9. Can chases be retrofitted in existing buildings?
Yes, but it’s more complex and may involve demolishing drywall or flooring to create the necessary path.
10. Are access panels mandatory in chases?
They are strongly recommended, especially in chases housing valves, joints, or electrical junctions, to allow for routine inspections and emergency repairs.
In conclusion, chases in construction are indispensable for integrating modern mechanical and electrical systems into buildings without sacrificing design, safety, or functionality. Whether you’re working on a residential project or a large commercial facility, a well-planned chase layout ensures efficiency, code compliance, and future adaptability—hallmarks of high-quality construction.
