4.1303.3 Insulation of Floor Cavity with Spray Foam Material

Topic:

Floors

Subtopic:

Manufactured Housing Floor Cavity Insulation

Desired Outcome:

Installation of a consistent thermal boundary Thermal boundary The separation between the interior and exterior environments of a building that slows heat flow between conditioned and unconditioned space that reduces heat flow

Manufactured Housing

Title	Specification(s)	Objective(s)
4.1303.3a R-value	Insulation will be installed in accordance with recommended R-value	Insulate to prescribed R-value for the climate zone
4.1303.3b Work assessment	Ensure complete accessibility of floor cavity	Ensure work area is clean, safe, and ready to accept insulation
4.1303.3c Preparation	All floor areas will be open and accessible for spray foam application Any openings in the subfloor larger than ¼" will be covered with appropriate materials Insulation dams or end blockers will be installed where needed All surfaces where spray foam is applied will be clean, dry, and free of contamination and degradation Substrate surfaces will be wiped, blown, or vacuumed to be free of excessive dust and dirt Grease and oil will be removed using appropriate cleaners or solvents Moisture content of all wood substrate materials will be below 19%; if tested at or above this percent of moisture, insulating the floor will be deferred until moisture level is corrected Clean floor cavities Remove all remnants of previous insulation and bottom board	Prepare all substrate surfaces for the application of spray foam
4.1303.3d Installation	Insulation will be installed to prescribed R-value in accordance with manufacturer specifications In accordance with manufacturer specifications, spray foam will be applied to desired thickness using the maximum pass thickness onto subfloor between floor joists and all rim/band joists Rim/band joist will be sealed When desired, underside of joists will be covered with spray foam to provide a layer of continuous insulation Each cavity will be insulated to specified R-value Insulation must be in contact with subfloor Insulation will not have gaps or voids Ducts and water lines will be insulated for climate conditions	Insulate and seal floors Eliminate voids Minimize conductive and convective heat transfer across the floor system Ensure durability
4.1303.3e Materials	Insulation will be installed in accordance with manufacturer specifications Flame spread index of selected materials will not exceed 25 with an accompanying smoke-developed index not to exceed 450 when tested in accordance with ASTM ASTM ASTM International, www.astm.org E 84 or UL UL Underwriters Laboratories 723 Flame spread index of foam insulation will not exceed 75 and a smoke- developed index of no more than 450 when tested in the maximum thickness intended for use in accordance with ASTM ASTM ASTM International, www.astm.org E 84 or UL UL Underwriters Laboratories 723 Foam insulation will be separated from the interior of the building by an approved thermal barrier at minimum 1/2" gypsum or a material that is tested in accordance with the acceptance criteria of both the Temperature Transmission Fire Test and the Integrity Fire Test of NFPA NFPA National Fire Protection Association, www.nfpa.org 275	Ensure durability Ensure worker safety Ensure proper installation Fire safety will be maintained
4.1303.3f Fire protection	Spray foam will be separated from the occupied space of the building with a 15-minute thermal barrier (typically 15/32" sheathing, 1/2" gypsum board, or approved thermal barrier coating) or as approved by ASTM ASTM ASTM International, www.astm.org E84 requirements Spray foam designed to be used as a fire block does not require a thermal barrier installed prior to application	Provide necessary fire protection for combustible spray foam insulation
4.1303.3g Occupant education	A dated receipt signed by the installer will be provided that includes: Coverage area Thickness R-value	Document job completion to contract specifications Confirm amount of insulation installed Comply with 16 CFR 460.17