Homebuilders

SPF insulation can be used virtually any location within the residential building enclosure. The illustration below shows typical locations where SPF insulation may be used. The SPFA Building Envelope Committee has prepared a detailed guidance document, SPFA-112 on the installation of SPF in residential buildings.
The table below shows residential assemblies where SPF can be applied. It also provides the type of SPF insulation used (open or closed cell), along with references to SPFA TechDocs and references in applicable sections of the 2018 ICC model building code.
SPFA TechDocs are detailed industry-concensus guidance documents prepared by SPFA's Building Envelope Committee. These can be obained from SPFA's Online Store.
APPLICATION OF SPF IN RESIDENTIAL BUILDINGS
Assembly | Closed-Cell (med density) | Open-Cell (low density) | Applicable SPFA TechDoc(1) | 2018 IRC Reference |
2018 IECC Reference |
---|---|---|---|---|---|
Building Envelope Air Leakage | YES | YES | N1102.4, N1102.4.1, Table N1102.4.1.1 |
R402.4; R402.4.1, Table R402.4.1.1 |
|
Exterior Walls - Framed Cavity (3) | YES | YES | N1102.1.1, Table N1102.1.2 | R402.1.1, Table R402.1.2 | |
Exterior Walls (hybrid cavity with SPF and fibrous insulation) | YES | NO | SPFA-146, SPFA-147 |
R702.7.1, Table R702.7.1, N1102.1.1, N1102.1.2, N1102.1.3, |
R402.1.1, R402.1.2, R402.1.3 |
Exterior Walls - Exterior Continuous | YES | NO | N1102.1.1, N1102.1.2, Table N1102.1.2, N1102.1.3 |
R402.1.1, Table R402.1.2, R402.1.3 |
|
Interior Wall Soundproofing | YES | YES | --- | --- | |
Above Ceilings (floors of ventilated attics) |
YES | YES | Note 2 | N1102.2.1 | R402.2.1 |
Below Floors (framed floors) |
YES | YES | Note 2 | N1102.2.8 | R402.2.8 |
Cathedralized Ceilings (3) | YES | YES | SPFA-141 (Note 2) |
N1102.2.2 | R402.2.2 |
Unvented Attics (3) | YES | YES | SPFA-141 (Note 2) |
R316.5.3, R806.5 | --- |
Outside Ductwork | YES | NO | (Note 2) | M1603.1.3, M1601.4.6 |
--- |
Unvented Crawlspaces | YES | NO | SPFA-152 (Note 2) |
R408.3; R316.5.4, N1102.2.11 |
R402.2.11 |
Conditioned Basements | YES | NO | SPFA-152 (Note 2) |
N1102.2.9 | R402.2.9 |
Foundation Walls (exterior side of below-grade walls) | YES | NO | SPFA-140 (Note 4) | N1102.2.9, R316.7, R318.4 |
R402.2.9 |
Below Concrete Slab-on-grade | YES | NO | SPFA-153 | N1102.2.10, R316.7, R318.4 |
R402.2.10 |
- It is recommended to consult the applicable SPFA Technical Documents for more information on these applications.
- SPFA-126 “Thermal and Ignition Barriers for Spray Polyurethane Foam Insulation”.
- SPFA-140 “Spray Polyurethane Foam Insulation for the Exterior of Foundation Walls”
- SPFA-141 “Spray Polyurethane Foam Insulation for Unvented (Conditioned) Attics and Cathedralized Ceilings”
- SPFA-146 “Spray Polyurethane Foam Insulation for Hybrid Insulation Systems – Part 1: Warm Climates”
- SPFA-147 “Spray Polyurethane Foam Insulation for Hybrid Insulation Systems – Part 2: Cold Climates”
- SPFA-152 “Spray Polyurethane Foam Insulation for the Interior of Basement and Crawlspace Walls”
- SPFA-153 “Spray Polyurethane Foam Insulation Below Concrete Slabs"
- When SPF is left exposed without a thermal barrier prescribed by the model building codes (e.g., ½: gypsum board), additional fire protective coverings or coatings may be needed. Consult SPFA-126 for more information on thermal and ignition barriers for SPF insulatio
- Assemblies using open-cell SPF in colder climates may require a Class II or Class III vapor on the interior side of the SPF. Consult with building code requirements, product technical data sheets and code compliance reports.
- Below-grade exterior applications may require protective elastomeric coatings