Assessing a concrete commercial building requires a clear understanding of construction types. This article focuses on concrete panels precast in a factory and summarizes how they are manufactured, transported, and assembled. That background helps identify the type of concrete construction during an inspection and better assess its condition in the field.

History of Precast Concrete

In 1905, British engineer John Alexander Brodie pioneered the use of precast concrete panels as a repeatable system for prefabricating structures. It was not until the 1930s and 1940s, with advancements in prestressing technology, that precast panels became lighter, stronger, and more cost-effective to produce at scale. When these improved methods met the urgent need for post-World War II reconstruction, adoption took off.

In North America, precast concrete found important early applications, including the Walnut Lane Memorial Bridge in Philadelphia, widely regarded as the start of the modern U.S. precast industry. Use of precast concrete panels for buildings also developed through the 1950s. By 1954, the industry had grown enough to establish national manufacturing standards, design guidelines, and quality control with the founding of the Precast/Prestressed Concrete Institute (PCI).

Today, the precast concrete industry includes underground, conventionally reinforced elements (such as utility vaults, manholes, and drainage structures) and above-ground prestressed elements for architectural and structural applications like buildings, parking structures, and bridges.

What Are Precast Concrete Panels?

In contrast to concrete formed, cast, and cured in its final position, precast concrete panels are cast elsewhere on site or in a factory. Site-cast panels are formed, cast, and cured at the job site before being lifted into place. Factory-cast panels are manufactured in a controlled factory environment, then transported to the construction site.

How Are Precast Concrete Panels Made?

Precast factories manufacture both structural and architectural concrete. Structural concrete is designed to carry and transfer loads, whereas architectural concrete is designed for the finished appearance of exposed concrete. A precast concrete wall panel can be both architectural and structural. Manufacturing processes for both are similar and begin with preparing the panel table where the panel is sized and reinforcement, connection points, and finishes are incorporated based on engineered plans.

Panel Table and Size Limits

Precast panels are constructed on a table using forms to create their size and shape. Tables typically range from about 20 to 70 feet long and can accommodate one or multiple panels at a time. Panel dimensions are influenced by transportation limits because panels travel from the factory to the site by truck over public roadways. Oversized panels can require special permits and escort vehicles, which increase cost and travel time. That is a primary reason many fabrication tables and precast panels are limited to a width of about 14 feet 6 inches.

With that width limitation in mind, panels wider than about 15 feet can often be assumed to be site cast rather than factory cast.

Openings, Reinforcement, and Connections

Forms are used to block out openings for doors, windows, loading docks, vents, or other design elements. Wood is often used as a blockout for openings, while foam is often used for complex shapes or voids. Openings generally cannot be added to a precast panel after this phase.

While width is limited, a precast panel can be up to about 50 feet long. These panels are heavy and can flex when lifted, so reinforcement is added to prevent cracking or breaking. The most common reinforcement approach is prestressing: cables are arranged on the panel table, stretched tight, and concrete is poured around them. After curing, the cables are released, producing a panel stable enough for transportation and erection. Those tensioned cables should never be cut, which is why factory precast panels cannot be cut or manipulated after construction without structural consequences.

If panels are structural components that support loads from the roof, beams, or other building elements, additional steel reinforcement may be concentrated where those loads will be carried. Anchor points are embedded before the pour so panels can later be welded or bolted together on site. Lifting points are also added so panels can be moved repeatedly from form table to yard to trailer to building site.

Finishing, Curing, and Assembly

Surface finishing may include sandblasting or texturizing after the panel has been moved to the storage yard. Panels typically cure in the yard for about 28 days before transport. In some cases concrete is tinted before it is poured, which can reduce long-term painting and maintenance needs.

Once on the building site, each panel is hoisted into place by crane and secured according to the design until the building perimeter is complete.

Understanding this process helps explain why modification of a factory precast panel is a serious concern. If an inspector is aware of cutting or other modification to a factory precast panel, the client should engage an engineer or other qualified person for further review.

Source: Certified Commercial Property Inspectors Association (CCPIA). PHW Inspections is a CCPIA member. Original article: https://ccpia.org/how-precast-concrete-panels-are-made/

During commercial property inspections, retaining walls are often found at parking lots, along property boundaries, and where changes in site elevation create access to lower levels. Some walls serve only to retain soil, while others are integrated with stairways, ramps, or tiered landscape features. They range from large structures that span long distances and support significant changes in grade to smaller site walls used around building perimeters, service areas, or walkways.

This article reviews common types of retaining walls, inspection approaches, and common deficiencies buyers, owners, and property managers should understand.

Common Types of Retaining Walls

Retaining walls are installed to manage changes in site topography and are designed to hold back soil and prevent erosion on a slope or uneven surface. The way they achieve this depends on whether gravity alone is sufficient or whether additional supporting materials are required. For this reason, inspectors typically encounter either a gravity retaining wall or a reinforced retaining wall.

Gravity Retaining Wall

Gravity retaining walls are designed to hold back soil primarily through their own weight without additional reinforcement. These are often shorter walls constructed of poured concrete, concrete blocks, rock, boulders, or gabion systems. Most gravity walls are built with a slight backward slope, leaning toward the soil they are retaining. These walls typically do not include visible reinforcement. Although a concrete retaining wall may be reinforced internally with steel, it is not considered a reinforced retaining wall system unless it uses structural elements that extend and anchor into the surrounding soil.

Reinforced Retaining Wall

Reinforced retaining walls are often associated with taller walls or walls that must hold back larger volumes of soil or additional loads. These walls include some form of structural attachment to the soil to improve stability and resist movement, such as tiebacks, deadmen, or piles. Common construction materials include timber and poured concrete.

Wooden or timber retaining walls may make it easiest to determine whether reinforcement is present. Seeing a shift from the horizontal grain to an exposed end grain can indicate that a deadman or tie-back is present. Concrete retaining walls are more difficult to classify visually, as deadmen or tiebacks are often buried perpendicularly behind the wall, extending into the retained soil.

Inspection Approaches

The baseline scope of the International Standards of Practice for Inspecting Commercial Properties (ComSOP) is to inspect retaining walls when they are likely to adversely affect the structure. Two useful approaches are assessing stability through a plumb, level, square, and straight lens, and combining macro and micro viewpoints.

Structural Stability

Plumb, level, square, and straight (PLSS) is an inspection approach for visually assessing structural stability.

• Plumb: Looking for vertical alignment along the full height of the wall.
• Level: Looking at horizontal components for unevenness or deflection.
• Square: Looking for walls that are slanted inward or outward.
• Straight: Looking down the length of a wall to identify bows, waves, or irregularities.

Macro and Micro Viewpoints

• Micro viewpoint: Assessing the structure from close proximity.
• Macro viewpoint: Assessing the structure from a distance for a wide view.

Using both approaches can change how a condition is interpreted. A detail that looks like a defect up close may look less severe—or more concerning—when viewed in the broader context of the wall and surrounding site.

Common Deficiencies

Retaining walls can experience a variety of issues that may develop over time. The following conditions may indicate underlying problems that can compromise structural stability if left unaddressed.

Settling

A stable retaining wall relies on properly supported soil behind it. When the backfill settles or shifts, the surface above may dip or slump, placing added stress on the wall. Uneven grades, depressions, or separation near the top of the wall may indicate settlement or loss of support. These conditions should be noted, as ongoing movement can affect the wall’s stability over time.

Improper Drainage

The drainage system is typically made up of openings placed along the base or slightly above the base that allow trapped moisture to escape from behind the wall. Some walls may have French drains or other accepted methods of de-watering installed behind the wall.

Water trapped behind the wall can build pressure. Clogged openings, blocked pipes, or compacted backfill can prevent water from escaping, saturating the soil and leading to material deterioration. Standing water, erosion, or signs of moisture should be noted, as these may indicate inadequate drainage.

Cracking

Cracks may be present from settlement, soil movement, or other forms of stress. Common types include:

• Vertical crack: Runs up and down the wall. Evaluate for signs of movement, such as widening at the top or bottom. Concrete commonly develops vertical cracks, and a crack without evidence of movement may be less concerning but should still be documented.
• Horizontal crack: Runs across the wall and should be evaluated carefully for movement and stress.
• Stair-step crack: A stepped crack pattern commonly seen in masonry or block walls. This type of cracking may indicate movement or stress within the wall and should be evaluated with other observed conditions.

Wide and extensive cracks should be documented. Other potential issues include leaning or bulging walls, separation of segments, material deterioration, and clogged drainage.

A retaining wall that appears out of plumb, combined with settlement in the soil behind it, may indicate deficiencies related to wall design or backfill support and could adversely affect the structure. When observed, such conditions should be documented and may warrant further evaluation by a qualified professional.

Source: Certified Commercial Property Inspectors Association (CCPIA). PHW Inspections is a CCPIA member. Original article: https://ccpia.org/inspecting-retaining-walls-at-commercial-properties/

The baseline scope of the International Standards of Practice for Inspecting Commercial Properties (ComSOP) excludes predicting service life expectancy, providing repair estimates, or offering opinions of cost to remedy. However, understanding concepts like Estimated Useful Life (EUL), Remaining Useful Life (RUL), and Maintenance Frequency helps inspectors interpret observed conditions from an inspection, as well as go beyond the baseline scope to offer services and professional opinions, such as:

• Opinions of costs for maintenance, repairs, and replacements
• Context for observed conditions, recommendations, and conclusions in reports
• Priority and urgency of observed property conditions
• Cost to remedy tables
• Reserve forecast tables and other capital planning inspection services
• Maintenance-focused inspections

The EUL is the estimated operational lifespan of a system or component before replacement or significant repairs are required for continued operation, assuming normal operating conditions and reasonable maintenance practices. It’s a standardized number based on industry data and manufacturer information. It’s also referred to as useful life (UL) or life expectancy. The RUL is a subjective estimate made by the inspector of the number of remaining years a building element is expected to remain functional before needing replaced. Maintenance frequency refers to the projected interval, in years, at which a specific maintenance activity is expected to occur for a system or component.

Refer to the Understanding the Estimated Useful Life of Commercial Building Systems article to learn more, or download the PDF charts and guides below for a more comprehensive look.

Estimated Useful Life (EUL) Chart and Remaining Useful Life (RUL) Guide PDF

The EUL is a reference number, not a a guaranteed service life for a specific building element. Actual timelines vary based on installation, environment, use, and upkeep. Its used along with the components effective age to calculate the RUL. Depending on the scope of service, the UL and RUL are often included in cost to remedy, reserve forecasting, and other cost projection reports. Having a general understanding of these concepts can also help provide context in the field when assessing property conditions and offering opinions in reports, such as recommendations and conclusions. Refer to the Free Estimated Useful Life Chart, or download the PDF below included with CCPIA® membership for future reference or to share with clients with a report or in marketing materials.

Estimated Useful Life (EUL) and Maintenance Frequency Chart PDF

The EUL and maintenance frequency represent two lifecycle clocks. One is tied to major repair or replacement, and the other is tied to expected maintenance activities. When maintenance is deferred, deterioration accelerates and replacement or substantial corrective work may be required sooner than the EUL, increasing the elements effective age. Viewing these estimates side by side adds the maintenance interval and care history factors that affect condition and projected maintenance costs. This is what distinguishes the combined chart from the EUL-only chart. Download the PDF below included with CCPIA membership for future reference or to share with clients with a report or in marketing materials.

Opinions of Costs for Suggested Remedies

Altogether, EUL, RUL, and maintenance frequency support assessing property conditions and understanding how to report them. Substantial repairs and replacements are often tied to EUL and RUL, while maintenance reflects planned work performed before a system or component fails. Deferred maintenance can fall between categories depending on the building element and current condition, but it often leads to significant repair or replacement.

These concepts connect directly to cost to remedy when providing opinions of immediate costs. When defining the scope of service, the inspector and client may set a dollar threshold, such as including items with costs exceeding $3,000 in the final work product. Maintenance items may fall within that threshold. In a reserve forecast, which projects costs across short-term, mid-term, and long-term tables, maintenance items may also be included. Defining the scope of service is important, as some clients want only physical deficiencies tied to repair or replacement. All of this supports inspection reporting that places property conditions in context based on care history and investment in proper upkeep.

The Cost to Remedy Fast-Track Course, held live on Zoom, reviews how to assess property conditions within the maintenance, repair, and replacement framework, and how to calculate costs for opinions of suggested remedies. Inspectors first determine the condition, then categorize it, identify the corrective action, and calculate the cost.

Refer to Cost to Remedy and Reserve Forecasting Resources for Commercial Property Inspectors page for additional guidance on

Source: Certified Commercial Property Inspectors Association (CCPIA). PHW Inspections is a CCPIA member. Original article: https://ccpia.org/estimated-useful-life-remaining-useful-life-and-maintenance-frequency-for-commercial-buildings/

The commercial property inspection process requires experience, knowledge of commercial building design to meet safety and functional standards, and a structured and consistent methodology. The following case study describes a commercial kitchen inspection based on this approach.

This case study evaluates a commercial building with two cooking areas. The cooking areas are located in separate sections of the building with no air communication between them. Cooking areas in commercial buildings can refer to a small breakroom kitchen or commercial kitchen operations.

This property has commercial kitchen operations, with cooking equipment that produces grease and other byproducts. For this type of commercial kitchen operation, a Type I kitchen hood with sufficient exhaust and make-up air system should be installed.

The inspector followed the Type I Exhaust Hood Inspection Checklist which addressed the following:

• Identifying the type of hood of equipment to ensure it handles grease and other byproducts
• Verifying the presence of AHJ-required cleaning and inspection tags on hoods and fire safety equipment
• Verifying the presence of fire safety features, such as suppression systems and fire extinguishers that are designed for grease type fires

The following are the prerequisites for performing commercial kitchen inspections:

1. Knowledge of how ventilation systems are interconnected
2. The hazards of grease-producing equipment
3. The emergency and safety design features of the kitchen equipment

For comprehensive training, refer to the Inspecting Commercial Kitchens Online Course for Commercial Property Inspectors.

Inspecting Kitchen One

Commercial Kitchen One underwent a routine inspection with the following observations:

1. The floors were made of sealed concrete.
2. The walls featured washable laminate.
3. The ceilings had washable tiles.
4. Two mini-split heat pumps were in use.
5. There was a door separating the cooking area from the rest of the building.
6. There were overhead doors leading to the loading dock.
7. There were interior doors connecting the loading dock to the prep kitchen.
8. There were interior doors connecting the prep kitchen to the main cooking area.
9. All doors were found to be ajar or slightly opened.

The image below shows the view between the main cooking area facing the open overhead door that leads to the loading dock (Image 1).

Image 1: View of the kitchen interior showing the main cooking area.

Main Cooking Area

On first pass, the main cooking area showed no obvious deficiencies (Image 2). However, a closer inspection is required to determine the condition of the kitchen and associated components for safety and proper operation.

Image 2: View of main cooking area.

The main cooking area underwent a closer inspection with the following observations:

1. The exhaust hood appeared to be in good physical condition meeting current design and manufacturer standards.
2. No post-installation modifications were found to the exhaust hood that would invalidate its original design.
3. The speciality labels were missing from the exterior side of the exhaust hood.Specialty labels refer to the manufacturer’s label, noting the type of hood in place (i.e., Type I or Type II).

1. Cleaning/inspection labels are placed on the hood after AHJ-required inspection. These labels identify the last time the hood was professionally cleaned and serviced.
2. Some hoods may also have a permanent tag that defines performance related criteria.

Note: Additional AHJ required inspection/cleaning tags or labels may be affixed to other systems such as fire extinguishers, suppression canisters, and manual activator devices. The label on the hood specifically covers that component.

Exhaust Hood Inspection

This cooking area is situated above grease-producing appliances, therefore a Type 1 hood is needed. Type 1 hoods use filters known as baffles. Type 2 hoods use non-baffle style filters.

The following factors assess the ability of the hood to allow exhaust air and grease to effectively pass through the baffle filters, and protect the kitchen in the event of an emergency when fire suppression is expelled.
The Kitchen One exhaust hood underwent a closer inspection with the following observations:

1. A Type 1 hood was identified (Image 3).
2. The exhaust hood filters were baffle filters.
3. The baffles were found to be installed vertically.
4. The baffles were free of grease buildup.
5. Suppression nozzles were positioned over the appliances.
6. Blast-proof light fixtures were located underneath the hood.
7. The exhaust fan and the fan control system were observed to be in good physical conditions with no visible signs of damage (Image 4).

Image 3: View of the Hood Interior.

Image 4: View of the Fan Control System and Switch.

The following deficiencies were observed during the inspection.

Missing Life Safety System Components

The three essential components of the life safety system were not found, namely:

• A Type K fire extinguisher
• Fire suppression system canisters
• A manual actuator for the suppression systems

A Type ABC fire extinguisher was found resting on top of the fan control system. However, an ABC fire extinguisher is not effective at extinguishing grease fires. A type K fire extinguisher must be located within 30 feet of the cooking appliances.

Fire suppression system canisters are typically located next to the fan control system, in the ceiling, or within the exhaust hood system. The inspector used a ladder to help trace the fire suppression system (Image 5).

Tracing the plumbing is a useful technique when portions of the suppression system cannot be found, since all pipes in the system usually connect to a single source/location. There should be visible nozzles under the hood to where the plumbing exits the hood to where the suppression system tanks are located.

Image 5: Tracing the Pipes to Locate the Fire Suppression System.

The inspector traced the pipe to the end of the hood. At the end of the hood, the pipe should exit vertically through the hood up to the suppression tanks. However, no other plumbing or fire suppression tanks or systems were found at the exit of the hood. Instead, a connector where the pipes should be was found (Image 6).

Image 6: View of the Top of the Hood and the Connector.

The suppression nozzles on this hood were never connected to a suppression system. Hence why the manual actuator was not found. Without a suppression system, there is no need for a manual actuator.

Missing Permanently Installed Vents or Ducts

There were no permanently installed vents or ducts found along the front of the hood.

The exhaust hood draws up large amounts of air to the outside. Vents or ducts should be permanently installed to provide make up / fresh air into the space to replenish what was removed by the exhaust hoods. Open tiles were noted in the ceiling during the inspection, but no permanently installed vents or ducts were present.

The exhaust hood was found to be in operation. Therefore, the inspector did not activate or cycle (turn on and off) the wall switch, nor did he request assistance from the workers to operate the exhaust hood.

A Deeper Look at the Make-Up Air Conditions

As previously mentioned, the cooking area was wide open. The doors connecting the large kitchen, the prep kitchen, and the loading dock were all open, allowing for unobstructed airflow. Given the issues found with the fire suppression system, it was anticipated that there might be problems with the make-up air system as well.

The roof of the building was not accessible, preventing the inspector from accessing the roof or any of its vent or duct systems. Therefore, the inspector used indirect inspection methods to determine if make-up air was being provided to the cooking area and exhaust system.

The inspector began closing each door one by one: first, the large overhead door, then the door between the loading dock and the prep kitchen, and finally, the door from the prep kitchen to the main cooking area. Each time a door was closed, it was drawn toward the main cooking area with increasing force. This behavior was a strong indication that the building did not have a make-up air system.

It appeared that the exhaust system was utilizing all of the open space and fresh air to compensate for the air being drawn up through the exhaust fan. When a door is closed, the air in that room is no longer available, creating a vacuum. Once the last door was closed, the exhaust system no longer had a source of fresh air, drawing it from wherever possible, including the heating system or other occupied spaces.

During colder months, the exterior doors remain closed. The exhaust system draws air as well as heat from the HVAC system. As a result, the HVAC system can no longer maintain the kitchen temperature at a comfortable level. Adding heat pumps was the simplest way for the building to provide extra heat without needing to add space heaters.

All exterior doors should open outward and should open quickly when a small to moderate force is applied, since it is a means of egress. With the exhaust hood system running and all other exterior doors closed, the inspector attempted to push open the exterior door. The inspector found that while the door opened, it required more force than when all the other doors in the building were also open. This indicated that the building was under a vacuum.

The inspector then opened the door slightly to create a small gap between the door and the frame, allowing a small amount of air to pass through. The inspector observed a significant rush of air being drawn through that gap, confirming that the cooking area lacked a make-up air system.

Reporting

Checklists help inspectors stay on task and mitigate omissions. They can be used to guide inspectors through systems they might not be familiar with and keep the most seasoned inspectors on target. The techniques used by these inspectors were largely visual. They did not provide any technically exhaustive measures. The inspector wrote the following comment on their inspection report:

“Issues are present in the cooking area that will require attention. A type K fire extinguisher was not present, and the suppression system was not installed, leaving the cooking area without any fire protection. The exhaust system does not appear to have a make-up air system. Make-up air systems may not be required in every cooking area, but as a result of the other conditions, we recommend further inspection and review by a qualified HVAC contractor to determine need.”

Use the following illustration, an understanding of how systems are interconnected, observed conditions, and a robust checklist to help guide inspections.

Inspecting Kitchen Two

Kitchen number two is located in the same building but in another wing (Image 7). The two kitchens do not share any common walls or HVAC systems. The inspector used the same checklists as for Kitchen One. The inspector was better prepared for this inspection knowing the significant safety issues observed with Kitchen One.

Image 7: View of Kitchen Two.

Commercial Kitchen Two underwent a routine inspection using the checklist with the following observations:

1. The fire suppression canister was found on Kitchen Twos exhaust hood (Image 8).
2. The date on the canister was found to be expired.
3. The manual actuator was located on the exhaust hood (Image 9).
4. A type K fire extinguisher was located on the floor within 30 feet of the cooking equipment.

Image 8: View of the Suppression Tank.

Image 9: View of the Manual Actuator.

Exhaust Hood Inspection

The Kitchen Two exhaust hood underwent a closer inspection with the following observations:

1. Two hoods were found separated by a 5-foot gap (Image 10)
2. The following elements were found in the gap (Image 10):The manual actuator
3. A refuse can
4. A refrigerator
5. A deep fat fryer (Image 11)

Type I hoods, also known as grease hoods, are designed to remove heat, smoke, condensation, and other grease byproducts of cooking. Not having the deep fat fryer under the Type 1 hood system leaves the fryer without fire protection and also prevents the grease from being captured by the system. Type 1 hoods should be installed above grease-producing equipment, such as cooktops, deep fryers, griddles, woks, charbroilers, and open-flame stoves; a Type II hood does not suffice.

Image 10: View of the gap between the hoods.

Image 11: The Deep Fat Fryer is located in the gap between the hoods.

The additional observations were made during the inspection:

1. Baffles were identified in both hoods.
2. The baffles had significant grease build up.
3. The baffles showed signs of extensive damage (Image 12).
4. Blast-proof light fixtures were found beneath both hoods.
5. The covers to some of the lights were missing.Covers are designed to protect the blast-proof light fixtures.

Image 12: View of Damaged Baffles.

Reporting

Kitchen Two shared some of the same issues as Kitchen One. Two separate report sections were created for each kitchen since there was sufficient separation between the two spaces. Combining the comments from both kitchens into one section would not accurately address the conditions and inform the client about the severity of the issues.

The inspector wrote the following comment about Kitchen Two:

The suppression system for this kitchen was found to be out of date. The hood system is not located over or servicing all of the appliances in the kitchen, including a deep fat fryer located outside of the hood enclosure. Also, components of the hood were observed to have failed. There are broken light fixtures and damaged baffles. The exhaust system was also observed to have grease buildup present throughout all of the baffles and hood panels. Attention is strongly recommended.

Use the following illustration, an understanding of how systems are interconnected, observed conditions, and a robust checklist to help guide inspections.

Conclusion

The purpose of the ComSOP (International Standards of Practice for Inspecting Commercial Properties) is to define best practices and establish a reasonable approach for inspecting commercial properties. The cooking area, or commercial kitchen, is often the main source of revenue for many businesses. However, the commercial kitchen can also pose significant safety hazards if not properly maintained or neglected. The Certified Commercial Property Inspectors Association has developed coursesand checklists to help inspectors navigate these complex areas of a building, ensuring they provide thorough inspections for their clients.

Identifying safety issues during these inspections can help prevent catastrophic situations, such as fires. If a fire does occur, the installed systems may allow for quicker suppression before it spreads to other areas of the property. The current user of this cooking area was unaware of any safety conditions; they were simply focused on operating their business.

Source: Certified Commercial Property Inspectors Association (CCPIA). PHW Inspections is a CCPIA member. Original article: https://ccpia.org/commercial-kitchen-inspection-connecting-the-dots-and-following-a-checklist/