Residential Buildings
Purpose
Regulations provide minimum requirements to safeguard public safety, health, and general welfare through affordability, structural strength, means of egress, facilities, stability, sanitation, light and ventilation, energy conservation, and safety to life and property from fire and other hazards to the building environment.
Requirements
Residential building for 1- and 2-family dwellings shall be reviewed for compliance under the current adopted edition of the International Residential Code (IRC).
The IRC shall apply to the construction, alteration, movement, enlargement, replacement, repair, equipment, use and occupancy, location, removal, and demolition of detached 1- and 2-family dwellings and townhouses not more than 3 stories above grade in height with separate means of egress and their accessory structures.
Residential Permitting Examples
An accessory dwelling unit is a 2nd dwelling unit on the same piece of property as the primary dwelling unit.
A dwelling unit is defined as a single structure providing complete independent facilities for 1 or more persons, including permanent provisions and fixtures for living, sleeping, eating, and sanitation.
Application
The submittal process for obtaining a building permit for an accessory dwelling is the same as for a single-family residence.
Zone Regulations
Accessory dwelling units are not allowed in all zones, and can be limited in size. Land Use Planners are available at Planning and Development Services to advise you on the various zoning and permitting requirements for an accessory dwelling. If you need assistance, call 360-778-5900.
Decks and walking surfaces over 30 inches above grade require building permits.
Plan Requirements
Detailed plans (PDF) are required for the permit including the following:
- Details of ledger and special connections
- Elevations
- floor framing and supports
- Floor plans
- Foundation
- Stair details when required
- Decks and walking surfaces over 30 inches above grade require building permits.
Plan Requirements
Sheetrock
Garages attached to residences require a fire separation consisting of 0.5 inches of sheetrock on the common wall of the garage and house to separate the residence and its attic from the garage. The sheetrock shall be continuous from the garage floor to the roof diaphragm. The sheetrock may terminate at the garage ceiling if the entire ceiling is sheathed with 0.5 inch sheetrock. If there is living space above the garage then the sheetrock on the ceiling shall be 0.625 inch type X.
Opening Requirements
There shall be no window openings between the house and the garage. Doors between the house and the garage shall be 1.375 inch solid core doors or other types of doors with a fire rating of 20 minutes or greater. Doors from the garage shall not open directly into a sleeping room.
Mechanical Equipment
Any mechanical equipment located in the garage that creates a glow, spark, or flame shall be mounted a minimum of 18 inches above the floor.
Floor Requirements
The floor where vehicles are parked shall slope for drainage to the main vehicle door.
Special Construction
Special construction is required at the main garage vehicle door where small wall sections and large beams are typically located. There are illustrated provisions in the International Residential Code (IRC) code book and the County Plan Review and Construction Guide offers prescriptive solutions to incorporate in your plans.
Detached Garages
For detached garages / buildings, please see the Accessory Structures page.
Townhouses are a single-family dwelling unit constructed in a group of 3 or more attached units in which each unit extends from foundation to roof and with open space on at least 2 sides.
Application
Townhouses that meet the definition shall be reviewed under the current International Residential Code (IRC). The submittal process for obtaining a building permit for a townhouse is the same as for a single-family residence. Townhouses are a single-family dwelling unit constructed in a group of 3 or more attached units in which each unit extends from foundation to roof and with open space on at least 2 sides.
Common Wall Requirements
The common wall between the units must be one 2-hour fire wall or two 1-hour fire walls construction and must be continuous from foundation to roof diaphragm and must be fire protected at the roof diaphragm for 4 feet out on both sides of the wall.
Pre-move Inspection
Pre-move inspections are not required for legally established structures located within Washington State.
All structures that are moved from out of State or out of Country (Canada) require a pre-move inspection performed by a Washington State licensed Engineer. The pre-move inspection form may only be obtained from the Planning and Development Office.
Once the pre-move inspection has been completed and the building has been approved to be moved, you may apply for a building permit to move your structure.
Building Permit
All moved structures require a building permit through Whatcom County Planning and Development Services. A Building permit is required to construct a new foundation under an existing or moved building. You will follow the same submittal process as for a regular building permit with the following changes to the required plan submittal:
Submittal Requirements
- Elevation drawings showing all 4 sides of the building (labeled North, East, South, and West).
- Plans should be 1/4 inches = 1 foot scale.
- Elevation views are needed to show the shape of the building, height, number of stories, and any covered porches or decks.
- Pictures of all 4 sides may be submitted in lieu of drawings
- Provide verification of roof framing as “engineered trusses” or “stick framed roof” so it can be determined how roof loads are/will be transferred to the foundation (i.e. full span trusses or stick framed roof that relies on interior walls for support.)
- Provide an as-built floor framing plan.
- Provide an as-built foundation plan and a new foundation plan
- Show perimeter foundation and interior pad or strip footings.
- Show size and location of access and vents.
- Provide new foundation details for perimeter foundations and all pad footings.
- Indicate dimensions, reinforcement, mudsills, anchor bolts, post to beam and footing connections.
- Show floor insulation and vapor barrier.
- Indicate how the existing floor framing will be positively connected to the new foundation at mudsills.
- The Washington State Energy Code requires installation of R-30 insulation in the floor and 6 milliliters black plastic vapor barrier in the crawl space.
- Smoke detectors must be installed in accordance with International Residential Code (IRC) 313.1 as well as carbon monoxide detectors in the existing buildings.
- Depending upon the complexity of the project, additional information may be required. (I.E. if the structure has to be cut into multiple sections to be moved)
- If the interior is to be remodeled or there will be additions to the moved structure, additional permits may be required.