What Is a Chase in Construction?
In construction and architectural design, certain elements work quietly behind the scenes to ensure buildings are functional, safe, and visually pleasing. One such essential yet often overlooked component is the chase. Whether you are working on a residential, commercial, or industrial project, understanding what a chase is and how it functions is critical for modern construction practices.
This in-depth article explores what a chase is in construction, its various types, design considerations, and best practices to ensure safety, accessibility, and code compliance.
🏗️ Definition: What Is a Chase in Construction?
A chase in construction refers to a recessed vertical or horizontal space built within a wall, floor, or ceiling to conceal and carry mechanical, electrical, and plumbing (MEP) systems. It serves as a dedicated path for routing pipes, conduits, ducts, and other utilities through a building.
Chases are not rooms or occupied spaces; rather, they are hidden architectural voids that keep essential building systems organized, protected, and out of sight, while also allowing for future maintenance and upgrades.
🔍 Key Features of a Chase
- Hidden Integration: Conceals MEP components within walls or ceilings.
- Access-Friendly: Often includes panels or doors for inspection or repair.
- Fire and Sound Rated: Built using materials that can prevent fire spread and minimize noise.
- Custom-Sized: Designed based on the type and quantity of services it needs to carry.
🧱 Why Are Chases Used in Construction?
Chases serve multiple critical purposes in both new construction and renovation projects:
1. Concealment of Building Services
They provide an unobtrusive way to hide plumbing lines, HVAC ducts, or electrical wiring, maintaining a clean and seamless interior aesthetic.
2. Simplified Maintenance
Chases offer easy access points to service systems without damaging structural components.
3. Efficient Routing
They allow for centralized and strategic utility pathways across multiple floors or rooms.
4. Code Compliance
Chases help meet local building codes regarding utility separation, fireproofing, and soundproofing.
🧰 Types of Chases in Construction
There are several types of chases used in building design, each serving a different utility function:
1. Pipe Chase
- Used primarily to run water supply, drain, and vent pipes.
- Common in bathrooms, kitchens, and mechanical rooms.
- Often vertical and runs through multiple floors.
2. Electrical Chase
- Conceals wiring and conduits for power, lighting, and data communication.
- May also include junction boxes and control panels.
3. HVAC or Duct Chase
- Built to house heating, ventilation, and air conditioning ductwork.
- Can be horizontal (above ceilings) or vertical (shaft-like).
4. Utility Chase
- A general-purpose chase used for multiple services such as plumbing, electrical, and gas.
- Requires careful coordination between trades.
5. Floor and Ceiling Chases
- Horizontal paths within raised floors or dropped ceilings.
- Common in commercial buildings, hospitals, and high-tech facilities.
📐 Design Considerations for Chases
Proper planning is essential to ensure a chase functions correctly, is safe, and complies with regulations. Here are key factors to consider:
| Design Factor | Recommendation |
|---|---|
| Size of Chase | Determine based on the number and diameter of utilities it needs to carry. Allow extra space. |
| Separation Requirements | Maintain proper spacing between electrical, plumbing, and HVAC systems to avoid interference. |
| Fire Resistance | Use fire-rated materials and firestop sealants where required by code. |
| Accessibility | Include removable panels or hatches for inspections and repairs. |
| Noise Control | Install acoustic insulation if the chase is adjacent to occupied spaces. |
| Code Compliance | Follow IBC, NFPA, NEC, IPC, and local codes depending on building type and location. |
🔥 Fire-Rated and Soundproof Chases
When chases penetrate fire-rated walls or floors, they must be built to contain or prevent fire spread. This includes:
- Fire-rated drywall or gypsum shaft liners.
- Firestopping around pipe or duct penetrations.
- Use of UL-listed fire collars or caulks.
- Sound-insulating batts to reduce noise from running water or air systems.
🧱 How Is a Chase Built?
1. Planning
- Architects and MEP engineers decide where chases are needed during design development.
2. Framing
- Chases are framed using wood or metal studs, depending on the project type.
3. Utility Installation
- Pipes, cables, and ducts are routed through the chase before enclosure.
4. Enclosure
- The chase is covered with drywall or panels, often with fire-rated or soundproof materials.
5. Final Touches
- Access panels are added, systems are labeled, and firestopping is verified.
🏢 Applications in Various Building Types
| Building Type | Common Chase Usage |
|---|---|
| Residential Homes | Bathroom plumbing walls, behind kitchen cabinets |
| Apartments/Condos | Vertical risers for stacked unit plumbing and vent systems |
| Commercial Buildings | Ceiling chases for HVAC and electrical routing |
| Hospitals | Specialized chases for oxygen, gas, power, and communication |
| Hotels | Utility chases behind corridor walls for plumbing and HVAC |
📊 Chase vs Shaft vs Duct Space
| Feature | Chase | Shaft | Duct Space |
|---|---|---|---|
| Purpose | Conceals MEP systems | Large vertical opening for elevators/HVAC/fire | Dedicated path for air ducts |
| Size | Small to medium | Medium to large | Narrow to medium |
| Access | Usually has access panels | Access through mechanical rooms or shaft doors | May or may not be accessible |
| Use Cases | Plumbing, electrical, multi-use | Elevators, HVAC risers, fire service risers | HVAC distribution |
✅ Benefits of Using Chases in Construction
| Benefit | Explanation |
|---|---|
| Cleaner Appearance | Eliminates clutter from exposed pipes and wires |
| Easy Maintenance | Access panels enable fast repairs and inspections |
| System Organization | Centralizes services for simplified installation and coordination |
| Fire Safety | Can be built with fire-resistive materials to slow the spread of flames |
| Future-Proofing | Allows space for adding new utilities or systems during future renovations |
⚠️ Common Mistakes to Avoid
- Undersizing the Chase: Leads to overcrowded utility runs and poor airflow or access.
- Lack of Coordination Between Trades: Results in conflicting utility placement.
- Skipping Firestopping: Can cause failed inspections and serious fire hazards.
- Poor Access Planning: Makes routine maintenance expensive or destructive.
- Improper Sound Insulation: Causes noise complaints from adjacent rooms.
❓ FAQs: What Is a Chase in Construction?
1. Is a chase the same as a shaft?
No. A chase is generally smaller and used to route MEP services discreetly, while a shaft is a large vertical opening for things like elevators or large ductwork.
2. Do all buildings need chases?
Not all, but most modern buildings benefit from chases, especially multi-story buildings and those with extensive mechanical systems.
3. Can I run multiple utilities in one chase?
Yes, but there must be adequate separation between plumbing, electrical, and HVAC systems according to code.
4. How wide should a chase be?
The size depends on what it needs to house, but a minimum of 12 to 24 inches is common for small to medium chases.
5. Are chases fire-rated?
They can be. Chases that pass through fire-rated assemblies or multiple floors often need to be fire-resistive.
6. Can chases be added during renovation?
Yes, but it may require cutting into existing walls, ceilings, or floors, making it more complex than incorporating them into new builds.
7. What materials are used to build chases?
Typically, chases are framed with metal or wood studs and enclosed with gypsum board, sometimes using fire-rated or moisture-resistant panels.
8. Are access panels required?
Yes, especially if the chase houses valves, junction boxes, or cleanouts. Access panels make inspections and repairs easier.
9. What codes apply to chase construction?
Depending on the contents and location, relevant codes may include NEC (electrical), IPC (plumbing), IBC (building code), and NFPA (fire safety).
10. Is soundproofing necessary in chases?
Sound insulation is strongly recommended when chases are near bedrooms, offices, or other quiet zones, especially for noisy plumbing or HVAC ducts.
In summary, a chase in construction is a crucial feature that allows builders to integrate essential utilities without compromising aesthetics, safety, or access. Properly designed chases improve functionality, reduce long-term maintenance issues, and help structures comply with modern building codes. Whether you’re constructing a new building or renovating an old one, planning for utility chases is a smart investment in performance, safety, and longevity.
