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Room Additions

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67 PhotoHow Many Sets of Plans Do I Need To Submit?

Three complete sets of plans must be submitted. The plans must be drawn on substantial paper (minimum 18” x 24”) exactly as the building is to be constructed. Defaced, incomplete, indefinite or faded plans shall not be approved. A separate copy of the site and floor plan(s) is required for the Contra Costa County Assessor.

What Information Is Required on the Plans?

Site Plan

  • Obtain approval from the Planning Division.
  • Site plans must be drawn to scale with the job address, owners” name, lot dimensions and set back distances from property lines.
  • Show all existing structures and the proposed addition.
  • Show distances between all structures.
  • Provide a North arrow.

Foundation Plan

  • Provide a plan view of the foundation slab, and a cross sectional footing detail.
  • Show all hold down hardware and indicate anchor bolt size and spacing.

Floor Plan

  • Provide a plan view of the proposed job.
  • Indicate size and location of all doors, windows and headers.
  • Show size, spacing and direction of ceiling joist.
  • Identify all HVAC equipment, ducts, plumbing fixtures, electrical devises, outlets, lights and switches.
  • Show the existing use, square footage, and location, type and size of the window(s) in the adjacent room(s).
  • Indicate existing square footage of the entire house and proposed square footage of the room addition.

Roof Plan

  • If you are proposing a truss roof, provide engineering calculations.
  • If you are using conventional framing, indicate the size, type/grade, spacing, direction of rafters and sheathing.
  • Identify roof covering material.
  • Specify nailing requirement for the roof sheathing.

Exterior Elevations

  • Provide three (3) exterior elevations identified as front, left and right sides.
  • Show door, windows, finished floor line, wall bracing, exterior finishes and indicated the roof pitch.

Required Details

  • Provide a cross section of the proposed job.
  • Show foundation, wall studs, ceiling joists rafters and roof pitch.
  • Indicate size, spacing and proposed material.
  • If ceiling is vaulted, provide cross section.
  • Provide enlarged details of all structural hardware connections.

Finish Materials

  • Indicate ceiling, wall and floor finish on floor plan.
  • Identify proposed glazing (single or double) on floor plan.

Title 24 Energy

  • Provide wall, ceiling and foundation (slab or raised floor) u-values on cross section as per Title 24 energy compliance package.
  • Indicate manufacture’s name and model number of existing furnace and water heater.
  • Provide energy calculations and required forms as per Title 24 energy requirements.

This is not an all inclusive list and before you begin any project, you should contact the Building Division for more details.