Residential · Franklin County & St. Louis, MO
Building a new home, an addition, or a detached shop? CAS Electric handles the complete electrical scope — from temporary service and service entrance, through rough-in and inspections, to trim-out and final. We work with custom builders and homeowner-general-contractors across Franklin County and the Greater St. Louis area — Pacific, Washington, Union, Sullivan, St. Clair, Eureka, Wildwood, Villa Ridge, and Marthasville.
New construction is where good electrical planning pays off for the next 40 years. Circuit layout, dedicated appliance runs, structured wiring for data and A/V, generator-ready subpanel placement, EV-charger-ready garage circuits, and smart-lighting neutral pulls — all of it is cheap now and expensive later.
We start with a walk-through of your plans, ask about how you actually live (or plan to live) in the space, and then build a real electrical scope: service size, panel layout, circuit count, receptacle spacing, switching plan, lighting layout, low-voltage rough-in, and any specialty items (hot tubs, workshops, wine rooms, home theaters).
During construction we coordinate with the framer, plumber, and HVAC contractor so the trades don't step on each other, then handle rough-in inspection, cover-up, and trim-out on schedule with the drywall and finish trades.
New construction electrical is quoted per project based on square footage, fixture count, service size, and low-voltage scope. We provide a free written estimate after reviewing plans.
We walk your plans with you, capture how you'll use each space, and build a written electrical scope with fixture and device counts.
We set the temp service for the trades and coordinate any underground runs before backfill.
Boxes, wire, low-voltage runs, panel install, and everything else that has to be in before insulation and drywall.
Devices, fixtures, dimmers, appliances, and the final inspection to get you to CO.
Both. We're a regular sub for custom builders in the Franklin County area and we also work directly with homeowners acting as their own GC on a new build or addition.
At minimum: a 200-amp panel with room for expansion, a dedicated 240V run stubbed to the garage for a future EV charger, a generator-ready subpanel or transfer switch location, neutral wires at every switch (for smart-lighting later), and Cat6 to every TV, office, and access-point location. These are cheap during rough-in and expensive to add later.
For a full new-construction package, ideally 4–8 weeks before framing so we can review plans and set the temp service. Additions and remodels typically 2–4 weeks depending on scope.
Yes. We pull the electrical permit, meet the inspector at rough-in and final, and coordinate the Ameren service set with your builder's schedule.
Yes — we rough in Cat6, coax, speaker wire, HDMI conduits, and access-point drops as part of the electrical scope. Trim-out on jacks and terminations coordinated with your A/V or IT provider if you have one.
Licensed, insured, owner-operated. We respond to all estimates within 1 business day.