Building & Construction Site Inspections

After a project is permitted, you schedule inspection 1-3 days before you need it. Schedule in the order listed below. If calling to schedule, use the 3-digit inspection number. Virtual inspections don't require 3-digit number.

Set Up or Cancel Inspections  |    Building & Construction Codes  |  Residential Code Drawings 

What Inspectors Look For & How to Prepare

General Preparation - Mark all property lines clearly & have paperwork out and visible before inspector arrives. Show inspectors all approved plans, drawings, permits and correction notices. 

Erosion & Sediment Control 442- Schedule after erosion control measures are installed, and schedule an inspection even if you use only natural vegetation for erosion control. The erosion control measures must be in place before any clearing, grading, or other ground-disturbing activity starts. Erosion control means that you have silt fence, straw wattle in place, 25-ft vegetation strip, and construction entrance set up so that trucks and other vehicles entering and existing the site do not track dirt, gravel, mud or other site debris onto the road.  If you try to schedule and are not allowed, that usually means the inspection took place during the initial review and has already been closed. Inspection done by the Development Review (DevRev) inspectors in the Public Works Department.

Fire - For single-family or two-family residential structures, the building inspector will check to make sure that smoke and CO2 detectors, wood stoves and wood fireplaces are installed correctly at the time of heat pump, stove or final inspection. For non-residential structures, contact bobby.may@co.thurston.wa.us. or call 360-628-3409 the fire inspector's line.

Footing Postholes & Setback Inspections 111- Excavation for footings should be complete, and all required reinforcing steel should be in place. Any required forms and all bedding materials for an all-weather wood foundation system should be in place.

Foundation Wall Inspection 112- VIRTUAL OK Request this inspection after all forms and required reinforcement, foundation vents and access openings are properly installed, but before concrete placement. The virtual inspections immediately below are part of 112:

Foundation & Posthole Footings Inspections 111 - VIRTUAL OK Show all parts of the foundation in pics/vid by going around the structure and pointing out each item where the installation detail is different. Please use a tape measure to show the following: clearance to forms, clearance to ground where poured against the ground, footing size (for footing), wall thickness (for FND), height of wall (for FND), where rebar is tied in, that rebar is the correct size, spacing of verticals and horizontals, laps where required are sufficient length, where hold downs are tied in (for FND) and if/where any manufacturer recommended rebar is provided, anchors are in place, anchor spacing (for FND), venting if this is a crawl space or shown in rim joist on the plans (for FND).
  • Simple Posthole Footings for Pole Barn & Porch Inspections -  Show everything. Show wide-angle view of the entire site area showing a landmark so that the site can be identified as the area under construction, state the address, site plan, show where the property line(s) is in relationship to the structure (use a tape if closer than 20 feet to property line(s), Inspection card, approved set of stamped plans, show footing detail from the approved plans, show a chart that refers to the size of the footing and the pole size, identify each post with a letter or number & in the pic/vid state which post it is, show each individual post in cclockwise or counter clockwise order and state which order you are moving in, shine a light in the hole to verify concrete sack placement, extend a tape measure down into the hole and show the depth then the width, show the distance between the poles, measure the post size, move to the next hole repeat until done. See example video 1 above.  (LINK VID !!}

Concrete Slab Inspection 116- ONLY IF INDICATED BY THE WHITE COPY OF YOUR BUILDING PERMIT. If indicated as necessary on your building permit, request this inspection after all in-slab building service equipment, conduit, piping accessories, insulation, and other ancillary equipment are in place, but before concrete placement. Please note: this inspection is required only if noted on your building permit. 

Insulation Slab Inspection 110- Request this inspection when all foam board is in place and sealed.

Stap/Hold Down 124- Strap hold downs will be checked per approved plans. If substituting straps or hold downs, please be sure to have engineer's approval.

Shear Wall Nailing Inspection 131- Request this inspection after all framing members have been installed in the area where shear wall panels or lateral restraint panels have been specified on the plans. Required hold-downs and strapping must be in place and all nailing completed. No covering (installing siding, insulation, wallboard, etc.) may begin until this inspection is done.

Electrical Inspection - All electrical work is regulated by Washington Department of Labor & Industry (LNI), but please have your completed LNI paperwork on hand for us to check. Regulated by Washington Dept. of Labor & Industries,

Construction BMP Inspection (in the Thurston County Municipal Stormwater Permit (NPDES) Boundary area, see the NPDES map) 448- If this inspection is required, it will be listed on your permit. This is a second Sedimentation and Erosion Control inspection. Schedule before Framing, Mechanical, and Plumbing inspections. This inspection is required to ensure compliance with Sediment and Control Best Management Practices (BMPs) during construction.  Schedule this inspection only after you have reviewed your site and made any repairs/revisions (silt fences, wattles, 25-ft veg. strip, construction entrance, etc.). Inspection done by the Development Review (DevRev) inspectors in the Public Works Department.

Plumbing Rough-In Inspection 132- VIRTUAL OK Request this inspection after all drain, waste, vent and water supply piping is installed and during water or air pressure testing. The virtual inspection immediately below is part of 132:
  • Minor plumbing installations - Show copy of plumbing permit & plans, address numbers for the home, overall view of entire work area, each individual plumbing connection, height of vent connections, use level to show required slope, show how plumbing drainage system is isolated from the drainage system to perform pressure test, completed copy of plumbing water/air test self verification form signed by licensed plumber only if virtual inspection.

Mechanical Rough-In Inspection 136- Ready for inspection after all mechanical equipment and ducting (including bath fans, range hood – if ducted, gas piping and wood stove chimney(s) are installed and during air pressure testing of the gas pipes. The virtual inspection immediately below is part of 136:

  • Heat Pump & Ductless Heat Pump Inspection - VIRTUAL OK.  Show entire installation including location of the required CO2 detector and smoke detectors.

Framing Inspection 146- Ready for inspection after the roof, all framing, fire blocking, windows, chimneys, exterior siding and bracing are in place; all plumbing, mechanical and electrical are approved for cover; and energy code caulking and sealing are done.

Insulation Inspection 148- Request this inspection after all concealed areas (walls, cathedral ceilings, etc.) are insulated, but before covering. Accessible attics and under-floor areas will be inspected during the Final Inspection.

Wall Board / Gypsum Inspection 152- Required only if you have interior braced wall lines. Request this inspection after all interior and exterior gypsum board is in place, but before plastering is done or gypsum board joints and fasteners are taped and finished.

Wall Board / Fire Resistive Inspection (151) - This inspection is required only if you have fire resistive rated walls. 

Gas Line Pressure Test 136- VIRTUAL OK. Complete the gas line self verification form, and have on hand for us to check or email to building@co.thurston.wa.us.

Gas Water Heater - VIRTUAL OK. Show code-approved water heater access, seismic straps installed per manufacturer’s instructions, expansion tank if a backflow preventer is installed, pressure and temperature relief valve piped to the exterior terminating 6” above the ground, drain pan and outlet routed to an approved location – exterior or floor drain, gas combustion air, gas ‘B’ vent hookup, carbon monoxide detector for gas appliances installed near each bedroom area and each floor level, insulation under the water heater in unheated spaces or a concrete floor, completed copy of the gas line self verification form

LPG Liquid Propane Gas Test 136 & Tank Set Inspection 164- VIRTUAL OK.  Show overall view of the entire work area, provide any other information requested on the permit, show and note all these distances (tank to vehicular way or protection from vehicles, tank to structures, tank to other tanks, to combustible materials). Show all these above-ground parts (support pad, support for tank). Show all these below-grade parts (depth below grade, cathodic protection, regulator vent, cathodic testing report, backfill material). This inspection can be done during the Mechanical Rough-In Inspection 136 (see above).

Corrections from a previous on-site inspection - VIRTUAL OK.  Show copy of the corrections list & the corrected item.


Please use this final inspection checklist (PDF) to prepare for final.

Before scheduling any final inspection, these things must be complete:  

  • Make sure all septic drawings are reviewed and approved. See Record Drawing in final inspection checklist above.
  • Make sure all critical area / environmental inspections are complete- Review the white copy of your permit to see if this is a required part of your permit before scheduling. 
Final Electrical Inspection - After all electrical trim & appliances are installed, call the Washington State Department of Labor and Industries at (360) 902-5242 to schedule.

Development Review Final Inspections
  • Final Access Inspection 420- This is an inspection of the paved driveway approach (also called apron). This inspection must be scheduled before the 476 inspection. 
  • Final Development Review Inspection 476-  Complete all drainage system and soil amendments. Schedule this before Final building inspection. Must be inspected within three  days of the scheduled inspection date.
Final Building Inspection 160- Request this inspection after the grading is done, the septic as-built drawing is approved, and the home is ready for occupancy. The address that is clearly legible from the road should be posted. Carpeting, painting, interior doors, finish work are not regulated and don't have to be done before you schedule.

After reviewing the final inspection checklist (PDF), call to schedule. When all required inspections have been completed and approved, you will receive a Certificate of Occupancy. Your new home is now ready for occupancy. Ask the building inspector approving the final inspection of your home to give you the County copy of your approved Building Plans. Please keep these plans, your Certificate of Final Inspection, your permit card and other permit and construction documents in a safe place for future reference. If you decide to remodel or build an addition onto your home, these documents will serve as a record of what was constructed on your site and as a useful reference for your designer or builder. 


Manufactured Homes -  Inspectors check footing/runners, blocking/tie-downs, skirting and conduct a final inspection. Details in Manufactured Home Inspection checklist (PDF) & Manufactured Home Landing Detail drawing (PDF)