Plan structured cabling during framing.
New construction cabling rough-in costs 30-50% less than retrofit and enables design decisions (MDF placement, pathway routing, future expansion) that retrofit can't.
By Steven Lockhart · Reviewed by Alex Towery, C-10 #989290
Updated 2026-06-16
Structured cabling rough-in during new construction: install pathways (conduit, cable tray, J-hooks) during framing before drywall closes walls and ceilings; pull horizontal cabling before drywall finishing; install MDF/IDF infrastructure during equipment installation phase. Cost per drop $100-$200 (vs $200-$400 for retrofit equivalent). Enables thoughtful MDF/IDF placement, generous pathway sizing for future expansion, and clean cable routing without retrofit access compromises.
01What rough-in enables that retrofit can't.
New construction rough-in gives architectural freedom that retrofit doesn't. MDF and IDF locations chosen for optimal pathway distances, power access, ventilation, and security — not chosen because they're the only location where existing utility space exists. Pathway routing chosen for shortest runs, fewer pull-points, accessible future re-pulls — not constrained by what existing closed walls allow. Cable types and counts chosen for full design rather than retrofit-compatible subsets.
Future expansion capacity gets built in cheaply during rough-in. Adding 50% extra pathway capacity during framing costs little; adding the same capacity post-drywall costs 5-10x more. Adding spare conduit runs from MDF to potential future expansion areas, pulling spare strands of fiber, or installing larger cable tray sizes than current need are all cheap during rough-in. Buildings often last 30-50 years; cabling needs change 3-5 times over that span; rough-in capacity decisions affect every future refresh.
02Three rough-in planning decisions.
MDF and IDF locations
MDF (main distribution frame, central hub) and IDFs (intermediate frames, typically one per floor) need: dedicated rooms or closets with ventilation, dedicated electrical circuits, conduit pathways to all served areas, security (locking doors), and reasonable size for future equipment growth. Plan during architectural design phase, not after.
Pathway design
Conduit between MDF and IDFs, cable tray in plenum/utility ceiling areas, J-hook pathway in cleaner ceiling spaces, dedicated chases between floors. Size pathways with 50%+ extra capacity for future. Specify pull strings in all conduits for future cable pulls without re-fishing.
Power for network equipment
MDFs and IDFs need dedicated electrical circuits, often with UPS power for resilience. Plan circuit capacity (typical IDF needs 30A 120V minimum; MDF often 60A+), receptacle locations within the room, surge protection. Coordinate with electrical scope during rough-in.
03Standard new construction Marin commercial scope.
For typical Marin new commercial construction (10,000-30,000 sq ft office): MDF in basement or utility area, IDFs on each floor, fiber backbone conduit between MDF and IDFs, cable tray in plenum spaces for horizontal pathway, dedicated electrical circuits at each MDF/IDF, security keying for closet access. Rough-in cost typically $5-$12 per square foot for full structured cabling pathway infrastructure (excludes actual cable, which is pulled later).
Coordination with general contractor and architect happens during design development phase, typically 6-12 months before framing. Specifications include conduit sizes, cable tray paths, MDF/IDF room requirements, electrical scope at each network location, future expansion provisions. We commonly serve as cabling design partner on Marin new construction projects, working with the project's IT consultant and architect.
Common questions.
What's the cost difference between rough-in and retrofit?
Typically 30-60% savings during rough-in vs equivalent retrofit. Specific numbers: $100-$200 per drop during rough-in vs $200-$400 for retrofit; $5-$12 per sq ft for full structured cabling pathway during rough-in vs $15-$30 per sq ft for full retrofit. Beyond cost, rough-in enables design decisions that retrofit can't optimize — that strategic value often exceeds the direct cost savings.
How much extra capacity should I build in?
50% extra pathway capacity is a common starting point. For new commercial that may grow 20-50% over a 15-year cable life, 50% pathway headroom accommodates reasonable expansion without re-pulling. Conservative architects sometimes spec 100% headroom in commercial new construction. Cost premium for headroom is small (modest larger conduit/tray vs minimum-size); operational value is substantial.
Do I need an IT consultant during rough-in?
For larger commercial projects (>10,000 sq ft, multi-floor): yes, an IT consultant or cabling design partner adds significant value during design phase. For smaller projects (<10,000 sq ft, single-floor): often the structured cabling contractor (us) serves the design role directly, coordinating with the GC and architect. Discuss scope and approach during initial project planning.
Can I install cabling later if rough-in is done?
Yes — that's the value of proper rough-in. Pathways are in place; cabling pulls happen during later construction phase (after framing/drywall, before occupancy) using the prepared pathways. Future cabling additions and refreshes use the same pathways with pull strings. Rough-in enables structured cabling install on standard schedule plus future flexibility for 15+ years.
How do you handle pricing — flat fee or hourly?
Both, depending on scope. Routine service calls and predictable scope (panel replacement, EV charger install, transfer switch install, fixture replacement) are flat-fee quoted up front. Diagnostic visits and emergency scope are hourly because we don't know what we'll find. Either way, you get a written quote before work starts on anything significant, and we don't proceed beyond the quote without your sign-off.
How quickly can you schedule?
Depends on scope and season. Emergency dispatch: same-day across Marin County (1-3 hours business hours, 1-4 hours after-hours). Same-day standard service: 3-6 hours from call when capacity allows; otherwise next business day. Scheduled service work: 1-3 weeks typical. Larger projects requiring permits and PG&E coordination: 4-12 weeks depending on scope. We're upfront about timeline at the quote stage.
What warranty do you offer on work?
Our standard residential warranty: 2 years on labor, manufacturer warranty on parts (varies by product — typically 1-10 years). Major installs (panels, generators, EV chargers) often have longer manufacturer warranties (5-10 years). If there's an issue with our work in the warranty period, we come back and fix it at no cost. We also stand behind work past warranty — repeat customers and referrals matter more than a transactional fix.
Are you licensed and insured?
Yes. California State License Board C-10 Electrical Contractor #989290, in good standing. Carry general liability insurance and workers' compensation insurance as required by California law. Bondable on projects requiring it. Happy to provide proof of insurance to clients or property managers on request. License lookup: cslb.ca.gov.
Talk to a licensed electrician in Marin.
Family-run, C-10 #989290, 20+ years in the trade. Honest scoping, fair pricing, work that lasts.