Most people have some understanding of what drawings are, and how they are used in construction. However, it takes more than drawings to build a building. Along with the drawings, on nearly every project, we issue a project manual. Many people are unaware of the project manual, and I suspect most who have seen one don't pay much attention to it, for a couple of reasons. First, the project manual for a typical project will have two volumes, each one being two to four inches thick - enough to scare off all but the most curious. Second, it is not light reading, with countless pages of what appears to be highly technical mumbo-jumbo, full of strange acronyms and unknown terms, written in a style clearly not meant for entertainment. Obviously, few would be interested in the project manual!
But without it, the building can't be built. The project manual and the drawings are complementary - that is, they work together. Each needs the other, each serves a specific purpose, and each is used to show specific information that is not shown in the other. In the construction contract, they are treated as a single document.
Even to someone not involved in construction, it is obvious that the drawings show where the building will be on the site, what the outside will look like, what the walls of the rooms will look like, and where furnishings and equipment will go. Those who are more familiar with construction drawings know there is much additional information, including dimensions, details, location and types of materials, finishes, and more.
On the other hand, because what they say is not as obvious as the meaning of drawings, and perhaps because of their frightening appearance, specifications are not as well understood. In essence, they are instructions to the contractor. They provide detailed information about the materials, products, and equipment used in the building; they describe physical qualities, performance requirements, and other information that cannot be drawn. With that explanation, it should be clear why specifications are necessary.
Let's take a look inside a project manual, and see what makes it so important.
The table of contents is found in the usual location, and serves the same purpose as in any other book. The first part of each chapter is a number, usually with six digits, followed by a title. Unlike a typical book, where the chapters are numbered one, two, three, and so on, the numbers in a project manual have gaps. The reason is, chapter numbers and titles have been standardized, so a chapter about wood doors, for example, will have the same number and title in all project manuals. These numbers and the titles are defined by MasterFormat, an industry standard that assigns numbers and titles to thousands of building products and documents. These chapters are divided into large groups of related subjects, called Divisions, each of which contains specifications for broadly similar subjects. Together, the Divisions and section numbers are used in the same way as in a book with a few parts, each of which has several chapters.
Division 00 - Procurement and Contracting Requirements contains information about bidding; it also includes the contracts and forms used in the construction contract. Typical documents include:
- Advertisement for bids, or invitation to bid, which gives contractors general information about the project so they can decide if they are interested in the project.
- Instructions to bidders, which explain how and when bids are to be submitted.
- Bid form, used by bidders to state bid amounts.
- Owner-contractor agreement form.
- Conditions of the contract. The general conditions describe the responsibilities and relationships of the owner, the architect or other design professional, and the contractor.
Division 01 - General Requirements provides information that affects the contractor's operations, and specifies requirements common to the rest of the construction documents. Finally, everything from Division 02 to the end specifies the work results for the building. We'll talk more about that in a future column, but for now, we'll think of specifications as instructions that tell the contractor what products to use, and what is expected in the finished building.
As noted, drawings alone don't have enough information for the contractor to complete the project. While the drawings will show the location and size of a door, and may indicate it's a wood door, they say nothing else about what the door is made of - what's inside, what the wood veneer is, or what hardware is used. All of these things are found in the specifications. Similarly, the drawings will show the locations and sizes of exterior windows, but the specifications tell the contractor what the window is made of and how it's built. Just as important, the specifications provide the performance requirements - the insulating value, light transmittance, condensation resistance, resistance to air and water infiltration, and more.
While most people avoid the project manual, it is important that someone on the owner's staff read and understand it. Because project information is found in two places - the drawings and the project manual - it is only by using both that the project can be understood.
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