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
  1. 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"
  2. 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
  3. 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.
  4. Below-grade exterior applications may require protective elastomeric coatings
                                           
Get a copy of SPFA's 
Homeowner's Guide to Spray Polyurethane Foam