BIBS
Fiberglass blown behind fabric so open cavities fill around wiring, plumbing and framing details.
See How BIBS WorksInsulation · Spray foam
Spray foam for assemblies where air control matters.
Spray foam expands in place to follow framing and detailed penetrations. The right product, cell type and installed thickness depend on the location, cavity depth, vapor-control strategy, approved assembly and locally adopted requirements.
At a glance
- Where
- Rooflines, walls, rim areas, basements and crawl spaces
- Types
- Open cell and closed cell
- Role
- Insulation and air control in one application, where the assembly allows
- Decided by
- The assembly, the plans, and local requirements
What it is
Spray foam starts as two liquids mixed at the gun. It expands as it goes on, bonding to the framing and sheathing and following the gaps, penetrations, and edges that a cut material would have to be fitted around.
Because it can control air as well as insulate, where it goes matters. Open-cell and closed-cell foam behave differently, so the assembly decides which one belongs.
How it is installed
Review the assembly
Confirm the location, the cavity depth, the vapor-control strategy, and what the approved plans call for.
Protect the surrounding work
Mask windows, floors, and anything that stays exposed.
Spray to thickness
Build the foam to the specified thickness around framing, penetrations, and edges.
Check before it is covered
Check thickness and coverage before insulation, drywall, or any required covering goes on.
Where it fits
- Roof decks and rafter bays
- Exterior walls in new construction
- Rim joists and framing transitions
- Basement and crawl space walls
- Garages and pole buildings
- Specialty structures such as shipping containers
The product and the installed thickness for each application come from the approved plans and the product documentation.
Open cell or closed cell?
Both are spray foam, and both have a place. They differ in density, in how they handle vapor, and in how much room they need.
| Consideration | Open cell | Closed cell |
|---|---|---|
| Density | Lower density; a softer, lighter foam | Higher density; a rigid foam |
| Installed thickness | Usually needs more thickness for the same thermal target | Reaches a thermal target in less thickness |
| Vapor behavior | Vapor-open; the assembly may call for separate vapor control | Can act as a vapor retarder at sufficient thickness |
| Cavity depth | Suits deeper cavities and rooflines with room for it | Suits shallow cavities, rim areas, and tight spaces |
| Common applications | Where the plans call for a vapor-open layer that also controls air | Rim areas, foundation walls, pole buildings, and assemblies that need a vapor-retarding layer |
| Project specification | Named on the plans, or chosen with the builder for the assembly | Named on the plans, or chosen with the builder for the assembly |
The assembly decides the foam—not the other way around.
Built to the assembly. Installed for local inspection.
Thermal Shop works from the approved plans, the selected product documentation and the requirements adopted for the project's jurisdiction. We document installed depth or assembly details and coordinate questions before finishes cover the work.
Photos from our installers
From several jobs. Captions describe what each photo shows; the foam product on each job is not labeled.
Start your insulation project
Homeowners
Request a Free EstimateHow it works for homeowners
- Request a free estimate and tell us what you're working on and where.
- We look at the attic, the house, or the concern first, then recommend the material and give you options.
- We install the work you approve and clear the work area when the install is done.
Contractors
Request a BidHow it works for contractors
- Request a bid with your plans, specs, and the work you want priced.
- Insulation is priced on its own bid, separate from gutters and shelving.
- We schedule around site readiness and inspections, and clean up the work area when the install is done.