Why we won't give you a single week count
Every home addition timeline breaks down into roughly the same phases — design and permitting, foundation, framing, mechanicals, and finish — but how long each phase takes depends on your addition's size and complexity, your municipality's permit review speed and inspection scheduling, and factors outside anyone's control like weather during foundation work. A single-story family room addition and a full second-story addition with a new primary suite are not on the same clock, even though both go through the same phases.
What we can walk through is the general structure of the timeline, so you know what's happening at each stage and roughly what to expect from the sequence — without inventing a specific week count that wouldn't hold up across different projects. Your actual schedule is something we lay out in writing as part of your fixed-price contract, based on your specific scope.
Design and permitting
This phase covers finalizing the design, producing construction drawings, and submitting for permit review with your municipality. If your addition requires stamped architectural or structural drawings, that work happens here too. Permit review timelines vary by municipality — some move through plan review faster than others, and the completeness of the submitted drawings affects how many review cycles are needed.
This is also when any required zoning review — setbacks, lot coverage, variances if needed — gets resolved. Because this phase depends on both design decisions and external municipal review, it's the part of the timeline most affected by how quickly design selections (layout, key finishes affecting structural or mechanical planning) get finalized on your end.
Foundation through framing
Once permits are issued, foundation work begins: excavation, footings poured below frost depth, foundation walls or slab, and backfill. Michigan weather affects this phase more than any other — foundation work slows or pauses during hard freezes or heavy wet conditions, which is a real scheduling factor rather than an excuse.
Framing follows the foundation and is generally one of the more visibly fast-moving phases, since it's dry, above-grade work. This is also when the roof tie-in to the existing structure happens for ground-floor additions, or when the existing roof is opened for second-story additions — both of which get the structure weathertight as quickly as possible to protect the interior work that follows.
Mechanicals and finish
Rough electrical, plumbing, and HVAC are installed once framing is inspected and approved, followed by a rough mechanical inspection before insulation and drywall close up the walls. Because Qualified Construction keeps licensed electrical and plumbing trades in-house, this phase is scheduled as one coordinated sequence rather than waiting on separate subcontractors' availability.
Finish work — drywall, flooring, cabinetry, trim, paint, and fixtures — is typically the longest single phase in terms of on-site days, since it involves the most trades and the most homeowner selections. A final inspection closes out the project once all work is complete and signed off by your municipality.
Daily site cleanup happens throughout every phase, and your written contract locks in the fixed schedule up front — so while the exact number of weeks depends on your specific addition, you'll know what that number is before construction starts, not partway through it.
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