Spray foam problems (odor, poor adhesion, gaps, moisture, or foam that has to come out before a sale or a roof job) need a contractor who knows chemistry as well as carpentry. Here is how to pick one, what to ask, and what California’s contractor rules say.
Last updated October 15, 2026. Free to read, no sign-up. Sources are linked at the bottom.
Step 1: Check the license (5 minutes, free)
In California, anyone who does a home improvement job worth $1,000 or more (labor and materials together), or any job that needs a building permit, or uses employees, must hold an active license from the Contractors State License Board (CSLB). The smaller-job exemption rose from $500 to $1,000 on January 1, 2025.
- Ask for the license number in writing. Licensed contractors must put it on their bids, contracts, and ads.
- Look it up free at CSLB's Check a License page.
- Confirm three things: the status is active, the business name and address match your quote, and the classification fits the work. Insulation work, including spray foam, is the CSLB C-2 Insulation and Acoustical classification. Spray foam roofing is roofing (C-39). If drywall or framing has to be replaced, a B General Building contractor may be involved too.
- On the same page, look at the bond (required to stay licensed), workers' compensation (a policy on file, or an exemption that means "no employees"), and any disciplinary or legal actions.
A company that arrives with a crew but shows a workers' comp exemption is a red flag: if an uninsured worker gets hurt on your property, you can be pulled into it.
Step 2: Ask for insurance in writing
A CSLB license is not insurance. Ask for a certificate of general liability insurance that names the business on your quote, and check the dates. If anything looks off, call the insurer listed on the certificate. Liability insurance covers damage to your home or a neighbor's property; workers' comp covers the crew. You want both when more than one person is on the job.
Step 3: Get 3 written, itemized quotes
Ask at least three companies to quote the same scope so you compare like with like. A useful quote lists:
- Every item of work, with materials named by brand, model, or grade where it matters
- Who pulls and pays for permits, and whether inspection fees are included
- Demolition, haul-away, and cleanup
- Start date, expected finish date, and what can cause delays
- A payment schedule tied to finished stages of work
- Warranty terms in writing
A much lower bid usually means something is missing. Ask each company what is not included.
Published ranges: removal about $3–$8 per sq ft for open-cell and $5–$12 for closed-cell (Dropcurb removal guide); new foam about $1.50–$3.50 per sq ft open-cell and $3–$5 closed-cell, often with a $1,000–$2,000 minimum job fee (HomeGuide); drywall repair about $1.50–$3.50 per sq ft. Estimates only; try our repair cost estimator.
Compare how each company will contain dust, ventilate, dispose of waste, and what they’ll put back after removal.
Permits
Insulation removal or replacement alone often doesn’t need a permit, but work that opens walls, touches electrical, or is part of a remodel or re-roof may. California’s energy code (Title 24) applies when insulation is replaced, so ask how they will meet it. Make permits the contractor’s responsibility in the contract.
Health and safety: the U.S. EPA notes that spray polyurethane foam chemicals can cause breathing problems, and that occupants should stay out during application and for the time the manufacturer specifies. Ask for the product name, its safety data sheet, and the written re-entry time before work starts.
The contract and payments: California rules that protect you
- Down payment: no more than 10% of the contract price or $1,000, whichever is less (CSLB).
- Pay as work is done. Pay only for work that's completed, never ahead of it.
- Right to cancel: for many home improvement contracts you have 3 business days to cancel, and 5 business days if you're 65 or older (CSLB homeowner checklist).
- Changes in writing, signed before the extra work starts.
- Liens: your contract should include the "Notice to Owner" about mechanics liens. An unpaid supplier or sub can file a lien even if you paid the contractor, so ask for lien releases as you pay.
- Don't pay in cash, and keep a job file with the contract, receipts, photos, and warranties.
Warranties
Ask for a written workmanship warranty and the manufacturer’s product warranty for any new foam, including what voids it. If you’re removing foam because of a problem, ask the contractor to write down what they think caused it.
How to read reviews
- Read the 1- and 2-star reviews first, then how the owner replied. A calm, specific reply that fixes the problem is a good sign.
- Look for recent reviews describing jobs like yours in your part of the county.
- Be wary of a sudden burst of short 5-star reviews with no details.
- Ask for 2 or 3 recent customers you can call, or finished jobs you can drive by.
- Reviews tell you about service. They don't replace the license and insurance check.
Questions to ask before you sign
- How long have you been licensed under this business name?
- Who will be on site: your employees or subcontractors? Are subs licensed and insured?
- Who pulls the permit, and is the inspection fee in the price?
- What is not included in this quote?
- What warranty do you give on labor, in writing, and for how long?
- How are change orders priced if you find a problem after you start?
- What product will you use (or remove), and can I see the safety data sheet?
- How long must we stay out, and how will you ventilate?
- How will you contain dust and dispose of the removed foam?
Red flags
- No license number, or a number that belongs to a different business name
- A big deposit, or pressure to pay in cash
- "Today only" pricing or door-to-door offers after a storm or fire
- No written contract, or one that is vague about materials and dates
- Asking you to pull the permit as the "owner-builder" (that makes you responsible)
- Payments that run ahead of the work
- Telling you it’s fine to stay home during spraying
- No product name or safety data sheet available
Questions
How do I check a spray foam contractor license in California?
Ask for the license number and search it free on the CSLB Check a License page at cslb.ca.gov. Make sure the status is active, the business name matches your quote, and the classification (C-2 Insulation and Acoustical) fits the work. The same page shows bond, workers’ compensation, and any disciplinary actions.
How much deposit can a spray foam contractor ask for in California?
For most home improvement contracts, no more than 10% of the contract price or $1,000, whichever is less, according to CSLB. After that, pay only for work that is finished.
Do I need a licensed contractor for a small job?
Since January 1, 2025, California’s minor-work exemption covers jobs under $1,000 including labor and materials, and only if no building permit is needed and the person has no employees. Anything else needs a CSLB license.
Can I cancel a home improvement contract after signing?
Often yes. CSLB says a 3-day right to cancel applies to many home improvement contracts, and a 5-day right applies if you are 65 or older. Check whether it applies before work starts.
How long should I stay out of the house after spray foam?
Follow the re-entry time from the foam manufacturer, in writing from your contractor. The U.S. EPA advises occupants to stay out during application and for the period the manufacturer specifies, with ventilation.
Sources (checked October 15, 2026)
- CSLB: Check a License
- CSLB: Hire a Contractor (consumer guide)
- CSLB: Homeowner checklists (down payment, 3-day and 5-day cancel, payment schedule, lien notice)
- CSLB: Senior Scam Stopper
- U.S. EPA: Spray polyurethane foam (SPF)
- HomeGuide: spray foam insulation cost
- HomeGuide: drywall installation cost
- CSLB: License classifications