Grid Lines In Architectural Drawings

Gridlines & Dimensions

Contributed by Gabriel Chek

In this post, we will learn about dimensions and gridlines as annotations on plan. These are important for a coordinated placement of building elements such as walls, columns and other structures.

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Gridlines & Dimensions between gridlines indicate where a building element is placed based from a reference point on plan.

Dimensions and gridlines on plans aid in the construction of structural elements (walls and columns). The centerlines of these elements are indicated best to accurately position them on site.

Naming of these gridlines is crucial to help architects, engineers and builders identify positions of the intersections. Like B2 for the column. Alphabets are typically used for one axis while numbers are used for the other.

Aligning Gridlines

Gridlines are aligned to the center of internal walls and outer face of external walls. This arrangement allows for a fixing of the position of the four corners of the building and footprint to meet planning requirements by authority.

For internal walls, the alignment to the center lines of walls allow for a change in thickness of walls as advised by structural engineers without affecting the gridlines.

Do not move grid lines

Dimensions between gridlines should be fixed to prevent any confusion. If neccessary, architects should inform all parties before doing so.

Should there be any changes to the position of gridlines with respect to the four corners of the building (marked by survey coordinates), architects must update all parties.