CMCORKY'S MHS™ Corky's Corner™

Remodel project guide

Room Addition

A new room built onto the house: foundation, framing, roof, siding, windows, insulation, electrical, heat/air, drywall, flooring and paint.

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What the work involves

  • Design, engineering and zoning review
  • Foundation and framing
  • Roof, siding, windows and tie-in to the existing house
  • Mechanical, electrical, insulation
  • Interior finishes

What should happen, step by step

Use this as a checklist while the job is underway. If a step is skipped, ask why.

Durations are typical planning ranges from Corky's field experience, not guarantees. Weather, inspections, material lead times and surprises behind walls change them.

How long it usually takes

Additions commonly take a few months of construction, plus design and permit time beforehand that can take as long or longer.

Plan your dates with the Project Timeline Planner

General guidance only. Your contractor's written schedule is what counts.

Inspections to expect

  • Footing/foundation
  • Framing, sheathing/nailing
  • Rough-ins
  • Insulation/energy
  • Final (often with a certificate of occupancy or final approval)

Which inspections apply depends on your city or county. Ask your contractor to share each passed inspection result. Understanding permits & inspections

What a good bid includes

Check off each item on the bids you receive:

How to read a bid · Have one in hand? Second Look Review (from $25)

Payment schedule

Milestone payments: foundation, dry-in, rough-ins passed, drywall, final. Keep a meaningful final payment until final approval.

  • Pay a modest deposit, then progress payments tied to finished, visible milestones (e.g., 'rough-in passed inspection'), never to dates alone.
  • Keep payments at or behind the work completed - you should never have paid for much more than has been done and delivered.
  • Hold the final payment until the final inspection is passed, the punch list is finished and you have lien waivers.
  • Avoid cash. Pay by check or card so there is a record, and get a receipt for every payment.
  • Deposit limits vary by state: California, for example, caps a home improvement down payment at 10% of the price or $1,000, whichever is less. Arizona has no single statewide percentage cap that we are aware of, so negotiate it and put it in the contract. Check your state's rules.

Payment schedules & lien waivers

Red flags & common rip-offs

  • Starting without plans or permits
  • No written schedule or payment milestones
  • Payments far ahead of work completed
  • No mention of how the new roof ties into the old
  • Contractor asks you to pull an owner-builder permit
  • Plans not matching the permit set

Also watch for the general warning signs: large upfront payments, cash-only, no written estimate, pressure to sign today and no proof of license or insurance.

Questions to ask before you sign

  1. Who does the plans and engineering?
  2. What are the payment milestones tied to?
  3. How will the addition tie into the existing roof and walls?
  4. Does my HVAC and electrical service have capacity?
  5. What is excluded from the price?
  6. Who is the single person responsible for the schedule?

Get the answers in writing, in the contract. Always ask for the contractor's license number and proof of insurance, and check the license with your state or local licensing agency. How to hire a contractor · Quick question? Contractor's Desk ($5)

Warranty

Written workmanship warranty; know how to reach the builder for leaks at the roof tie-in.

Expect two kinds of warranty: the manufacturer's product warranty (shingles, windows, fixtures, equipment) and the contractor's workmanship warranty on the installation. Get both in writing with the length, what is covered and how to make a claim. Many product warranties require registration or installation per the manufacturer's instructions. In Arizona, a homeowner can file a workmanship complaint against a licensed contractor with the Registrar of Contractors within two years of the last work performed on a remodel or repair.

DIY vs. hire out

Usually OK to DIY

  • Painting, landscaping after

Hire a licensed pro

  • Everything structural, mechanical, electrical, roofing

Some work legally requires a licensed contractor and a permit even on your own home. Check your state and city rules.

Permits to expect

Additions require building permits and inspections, and usually zoning review. Permit rules are set by your city, county and state, so they vary a lot. Call or check the website of your local building department before work starts. When a permit is required, the licensed contractor usually pulls it in their own name.

General information, not legal advice. Requirements vary by location.

Sources

Check a contractor license: search your state's contractor licensing board, or find your state consumer protection office. External sites open in a new tab; Corky's MHS™ is not affiliated with them.

Please note

Educational information only - not legal, engineering or code advice. Rules vary by state, county and city, and change over time. Check with your local building department and licensing board, and read your own contract.