I get this question all the time when we are in conversations with owners who don’t live in the construction or design-build industry every day as we do. In light of this, we have decided to dedicate this blog post to several terms and acronyms that are common in the industry that owners and others would benefit from knowing. We hope it’s helpful!

  • Aggregate Base: A construction aggregate is typically composed of crushed rock capable of passing through 20 millimeters (¾ in.) rock screen. This is commonly used under hardscape on sites such as asphalt or concrete paving as well as building slabs and footings.
  • Anchor Bolt: These are used to anchor the above-grade structure or building to the concrete foundation.
  • Backing and Blocking
    • Backing: Installed behind the drywall in areas where items will be mounted to the wall such as ADA grab bars, wall hung shelves, door stops, etc. where they can’t be supported by a stud.
    • Blocking: Evidently, the term is derived from “blocks,” and means the use of short pieces or off-cuts of lumber in wooden-framed construction. Construction workers use the blocking technique for filling, spacing, joining, or reinforcing structures.
  • Bearing Wall: A wall that supports any vertical load in addition to its weight.
  • BenchMark: A mark on some permanent object fixed to the ground from which land measurements and elevations are taken.
  • Brick Veneer: A facing of brick laid against and fastened to the sheathing of a frame wall or tile wall construction.
  • Building Envelope: A building envelope is a physical separator between the conditioned and unconditioned environment of a building including the resistance to air, water, heat, light, and noise transfer. This would refer to the entire shell of the structure.
  • Cold Joints: A cold joint is a plane of weakness in concrete caused by an interruption or delay in the concreting operations.
  • Concrete Mix Designs: The appropriate selection and proportioning of constituents to produce concrete with pre-defined characteristics in the fresh and hardened states. The mix design will vary on the use, application, soil, and various other factors relating to your project.
  • Concrete Slab: One of the few construction elements that are used in the vast majority of all structures, a concrete slab is the thick horizontal concrete platform (average of 10 – 40 cm) that is created to construct the floor or ceiling. There are several slab designs (corrugated, ribbed, waffle, one-way) and each one corresponds to the design or endurance required.
  • Construction Manager vs General Contractor
    • Construction Manager (CM): is typically a firm hired by the project owner to oversee the project. Sometimes the CM hires a general contractor under them or they hire the subcontractors directly. The CM is typically an owner rep working on their behalf. As an owner rep, the CM usually carries less risk than the GC does.
    • General Contractor (GC): A GC is the firm hired to complete the overall project either by the owner or CM. They hold all the subcontracts and manage the day-to-day aspects of the project and carry the risk.
  • Course: Other than the class you take in school, a course is the term used to describe a continuous row of masonry. Whether it’s stones, bricks, or concrete blocks, a course can have several orientations and types.
  • Cross Bracing: Cross bracing is a structural component used to improve the endurance of a structure. The X-shaped reinforcement can prevent a building from collapsing completely in case of earthquakes, or a wooden chair from falling apart.
  • Cut and Fill: While creating railways and canals, construction workers would create cut slopes (like a mini valley) to install the railways. The soil that’s been moved, “the fills”, would subsequently create adjacent embankments, minimizing the labor. The approach is now frequently used on construction sites of any size.
  • Design-Build vs Design-Bid-Build
    • Design-Build: In most projects, construction is frequently delayed due to time conflicts between two (or more) teams involved. The idea behind design-build is that the same team who designs the project constructs it as well. It is a project delivery system in which the design and the construction are considered “single-point-responsibility,” reducing costs and delivering the project on time.
    • Design-Bid-Build: The oldest way of doing business in our industry. The owner hires a design team (typically the architect) to design the project. Once the design is completed, the design team submits for permits. While this is taking place, the owner bids out the project. Upon receipt of the bids, the owner must decipher any differences between them, so they can make an informed decision. Once the owner makes the decision, a contract must be negotiated and then the contractor is on board for the duration of the project. Since the contractor wasn’t part of the design process, any issues with the drawings typically are absorbed by the owner. This method takes more time and has more risk for the owner than design-build.
  • E.I.F.S. vs Stucco – These are commonly mistaken for each other. One is a complete system and one is just a material applied to a building envelope in place already.
    • E.I.F.S.: An acronym for Exterior Insulation and Finish System. It is a general class of non-load bearing building cladding systems that provides exterior walls with an insulated, water-resistant, finished surface in an integrated composite material system.
    • Stucco: A material is a fine plaster made of Portland cement, sand, and a small percentage of lime and applied in a plastic state to form a hard covering for exterior walls.
  • Encasement: On a construction site, encasement might refer to one of two things: in some situations, sewers and other underground pipes may need to be enclosed in a concrete encasement for structural reasons; or, the term might be applied to the process of encasing hazardous materials already installed in a structure such as asbestos.
  • Geotechnical Report: A tool used to communicate the site conditions as well as design and construction recommendations to the site design, building design, and construction personnel.
  • GMP vs Open Book vs Lump Sum Contracts
  • GMP: This is an acronym for Gross Maximum Price. Essentially what this means is, assuming the scope remains constant, the price will not exceed what was quoted or the GC absorbs the overage costs.
  • Open Book: Often used in many methods by Cambridge, the owner has full visibility of all subcontracts, markups, fees, labor rates, and material costs. Nothing is hidden.
  • Lump Sum Contract: In this case, the owner only knows the total price of the contract and doesn’t have visibility of any of the project detail costs. Once the scope is set, the price is determined, and the owner agrees to the number. Any savings on costs are typically kept by the selected contractor.
  • Hardware: This is typically referred to as doorknobs, locksets, and other items like that.
  • HVAC: Acronym for Heating, Ventilation, and Air Conditioning commonly used for the building heating and cooling system.
  • Joist: Joists are crucial components of a wide-span structure, as they help transfer the load from the beams to the vertical columns and studs. These horizontal elements are connected perpendicularly to the beams (horizontally) and joined (vertically) to the columns.
  • Main Frame: This is the part of the metal building that does the majority of the work. It typically spans the “long” way, entails columns and beams, and is the main structure holding the building together.
  • Masonry Unit: a standard size rectangular block used in building construction.
  • MPEFP: Acronym for Mechanical, Plumbing, Electrical & Fire Protection that is part of a drawing set.
  • PEMB vs Structural Steel Building:
  • PEMB: Acronym for a Pre-Engineered Metal Building. In this case, the company where you buy the building from does all the engineering for the structure fabricates it, and ships it to the project site.
    • Structural Steel Boiling: Typically designed by your project structural engineer and the columns, joists, beams, and other parts are procured through a vendor based on the sizes determined by the engineer.
    • Portal Frame: This is a secondary piece of a metal building that helps to fortify the building, so it doesn’t “rack” or “twist” under the loads imposed. Typically, these are used when cross bracing can’t be installed.
  • Pre-Cast vs Cast-in-Place
    • Precast Concrete: One of the most commonly used forms of concrete, precast concrete is concrete elements that are created off-site to be transferred or lifted to the site later. Designs could range from blocks to panels and create solid but maneuverable elements.
    • Cast-in-Place: Contrary to this, cast-in-place are concrete walls that are formed and poured on site as the construction takes place. Each has its advantages.
  • Purlin: A purlin is any longitudinal element implemented on the roof structure horizontally for additional structural or material support.
  • R-Value: This is a measure of a material’s resistance to heat transfer. The higher the R-value the more resistant it is to heat transfer. Typically, ceilings/roofs are required to have a higher R-value than exterior walls because heat is easier to lose through the roof than the walls due to the nature of heat rising.
  • Rafter: Rafters are a series of inclined wooden elements that form a roof, which attach to the edge of the wall plate and often overhang to form the eave.
  • Rim Joist: In flooring systems, rim joists are attached to the ends of the floor’s main joists, providing lateral support to the ends of the decking system. However, they are not the end joists, which are usually the first and last row, parallel to the other joists.
  • Shoring: Temporarily installed on site, shoring is the method in which metal or timber props are assembled to support the structure during construction. Shores can be installed vertically, horizontally, or diagonally, depending on the support needed.
  • Structural Masonry: This refers to a section of masonry used to support the structure above it. Not all masonry is structural, many times it is used as a veneer or non-supporting exterior or interior wall.
  • Tongue-in-Groove: This is a certain type of board that has a “tongue” on one side and a “groove” on the other so that when they are placed on the floor they connect to help strengthen the floor assembly and prevent squeaking.
  • Wind Column: These are “side” columns there to attach purlins to so the siding and insulation can be installed. They don’t do anything “structural” but they do support the wall mainly against wind loads.
  • Wall Stud: Wall studs are crucial members of wooden or steel wall frames, as they are the vertical elements that help support and transfer loads of bearing and nonbearing walls.
  • Water Closet: This is the industry term for a toilet.

Jeff Eriks – President