How to Compare Spray Foam Contractor Quotes Before You Sign

Compare the boundary before the price

“Insulate the attic” can mean sealing and insulating its floor, or moving the boundary to the roofline. Those proposals involve different areas and different building conditions. Ask the contractor to mark the boundary on a sketch and list included surfaces, access doors, transitions, and exclusions.

For example, one quote might include the roof deck and gable walls while another covers only the ceiling plane. Their price per square foot is not a like-for-like comparison. See the attic decision guide before treating either proposal as the preferred design.

Put the scope side by side

Ask each contractor	A useful written answer	A gap to resolve
Where is the enclosure boundary?	Marked surfaces and transition details	“Whole attic” with no drawing
What happens before spraying?	Repairs, inspection, preparation, access responsibilities	Foam proposed over unexplained staining
What material and thickness?	Exact system and defined installed target	A brand family and one average depth
How are people protected?	Work restrictions and responsible exposure-control lead	A universal return time with no conditions
What happens after spraying?	Inspection, covering, cleanup, records	“Finished” with exposed foam unresolved
What changes the price or schedule?	Specific exclusions and written change process	Open-ended extra work

These are questions for a complete proposal, not a contract template or an endorsement of a contractor.

Ask who owns the pre-work decisions

Identify who checks for water intrusion, damaged substrates, pests, hazardous existing material, and mechanical-system concerns. DOE’s home air-sealing checklist includes inspection and combustion, ventilation, and commissioning considerations. A spray crew’s arrival should not be the first time an unresolved condition is examined.

For a basement, the Building America foundation-retrofit guide places moisture correction before insulation. Ask whether that correction is included, excluded, or assigned to another contractor. If work reveals unexpected damage, agree who pauses the job and documents the next decision.

Separate the material claim from the installed result

Request the exact formulation and applicable label, SDS, TDS, manual, and evaluation report. Have the scope state how thickness and continuity will be checked at corners, edges, and transitions.

A deepest-point measurement or a claimed kit yield does not establish the completed assembly. The Building America roof-deck guide calls attention to installation quality, including substrate conditions and coverage. Use that as context for a project-specific inspection plan, not as a substitute for the manufacturer’s requirements.

Get the occupancy and covering plan in writing

Ask who coordinates residents, pets, other trades, HVAC protection, cleanup, and return instructions. EPA’s archived workplace-practices guidance recommends discussing re-occupancy before work begins. Plan for changes in conditions or schedule rather than assuming one fixed number of hours fits every installation.

Ask separately who supplies and inspects the required fire covering. Product surface-burning claims and assembly protection are different questions under the 2021 IRC example; the applicable local edition and approved assembly control the actual job.

Agree on the handover record

Request a marked boundary drawing, product and lot record, relevant installation logs, thickness and continuity observations, photographs before covering, covering details, and the applicable inspection record. Have the contractor explain the correction process and distinguish installer workmanship coverage from product-manufacturer terms without implying a guaranteed outcome.

Use the printable contractor checklist during the conversation. Compare complete scopes, including reasonable alternative materials, before selecting the price that fits your project.