United States
Hong KongReading plans and specifications
Drawings show location and dimension; specifications describe materials, quality and workmanship. Where they conflict, the contract order of precedence governs, and specifications generally prevail.
Two documents doing two jobs, and most questions are about which one answers a given question.
The drawing set
| Prefix | Discipline |
|---|---|
| A | Architectural |
| S | Structural |
| M | Mechanical |
| E | Electrical |
| P | Plumbing |
| C | Civil |
Each discipline draws the same building and shows different things. A conflict between them is a coordination problem. Raise it rather than choosing on site.
What specifications add
Materials, quality standards, submittal requirements, execution and acceptance criteria. They are organized into divisions by work type.
Division 1, General Requirements, applies across the whole project and is the division most often skipped by people who go straight to their trade section.
Always. Drawings distort in reproduction and scaling is unreliable. A question giving you a written dimension and a scale that disagrees is testing exactly this.
Details and sections
Referenced from plan views by symbols. A detail shows how something is built where the plan only shows that it exists.
Following the reference is a skill, and questions sometimes describe finding information without saying which drawing it is on.
Requests for information
Where documents conflict or are silent, ask in writing before proceeding. Building to your own interpretation shifts the risk onto you.
Submittals close the loop
Shop drawings, product data and samples are submitted for review before fabrication or installation. They confirm that what will actually be built matches what was specified.
A submittal reviewed and returned with comments is not approval to proceed as drawn. Reading the comments is the step that gets skipped, and rework is the consequence. Ask, do not guess.
Common questions
What is the difference between plans and specifications?
Drawings show location and dimension. Specifications describe materials, quality and workmanship.
Which governs a conflict?
The contract order of precedence, under which specifications generally prevail over drawings.
What is Division 1?
General Requirements, applying across the whole project rather than to one trade.
Do I scale a drawing?
No. A written dimension always governs, because drawings distort in reproduction.
What if the documents conflict?
Raise a request for information in writing before proceeding. Interpreting a conflict yourself shifts the risk to you.