4.1003.12 Roof Decks (Underside of Deck—Attic Space Ceilings)—Spray Polyurethane Foam Preparation and Application

Topic: 
Attics
Subtopic: 
Attic Ceilings
Desired Outcome: 
Proper preparation and installation of spray polyurethane foam ( SPF SPF Spray polyurethane foam ) to create continuous air and thermal boundary Thermal boundary The separation between the interior and exterior environments of a building that slows heat flow
For supporting material, see Referenced Standards and Building America Solution Center.
TitleSpecification(s)Objective(s)
4.1003.12a
Worker safety

All worker safety specifications will be in accordance with SWS 2.0100.3 Worker Safety

Ensure worker safety, especially in regard to fall protection considerations and contaminants found in demolition, such as asbestos, lead, polychlorinated biphenyls, etc.

4.1003.12b
Occupant safety

An occupant safety plan will be prepared and implemented

Ensure occupant safety

4.1003.12c
Pre-inspection

Conduct pre-inspection in accordance with SWS 2.0100.4 Work Area Inspection and Stabilization

Gaps, cracks, and holes in fire separations located within the work area will be visually identified and incorporated into air sealing work scope, including those that span two conditioned or unconditioned spaces

Where drawings are available that identify specific fire-resistance ratings (i.e., 1 hour, 2 hour), materials and methods will be employed to preserve or restore such rating

Where drawings are unavailable or do not identify specific fire-resistance ratings, the fire-resistance rating of the assembly may be inferred from the current construction (i.e., single 5/8 sheetrock, concrete masonry unit), and materials and methods employed will be consistent with restoring or preserving such inferred fire-resistance rating

Repairs necessary to stabilize work areas and protect or preserve integrity of energy improvement will be completed before subject work begins

Insulation will not be installed if moisture-related issues are not resolved

Identify and remediate pest, moisture, and air leakage and electrical problems before installing insulation

Ensure a durable, continuous air and thermal boundary Thermal boundary The separation between the interior and exterior environments of a building that slows heat flow

4.1003.12d
Surface preparation

All surfaces where SPF SPF Spray polyurethane foam is applied will be clean, dry, and in accordance with manufacturer specifications for ambient and surface temperatures

All existing attic floor insulation and vapor retarder Vapor retarder A material that slows the passage of water vapor and contains a perm rating above 1 will be removed

Ensure proper bonding of SPF SPF Spray polyurethane foam to substrate surfaces

Ensure the new conditioned space is coupled with the conditioned space

4.1003.12e
Installation of insulation dams

Attic space ventilation to be retained will be appropriately baffled and protected to allow for maximum application of foam insulation at exterior top plate/vent interface

Ensure insulation R-value is not reduced

Ensure continuous insulation and air seal of top plate and roof deck

4.1003.12f
Installation

Insulation will be installed to prescribed R-value in accordance with manufacturer specifications

SPF SPF Spray polyurethane foam will be applied to desired thickness onto roof sheathing between rafters or trusses, using a pass thickness maximum as indicated by manufacturer specifications

When specified, underside of rafters or trusses will be covered with SPF SPF Spray polyurethane foam to provide layer of continuous insulation

In colder climates ( IECC IECC International Energy Conservation Code Zones 5-8) SPF SPF Spray polyurethane foam will be installed to a thickness of least class II vapor retarder Vapor retarder A material that slows the passage of water vapor and contains a perm rating above 1 or have at least class II vapor retarder Vapor retarder A material that slows the passage of water vapor and contains a perm rating above 1 coating or covering in direct contact with the underside of the SPF SPF Spray polyurethane foam

In no case will the final thickness exceed the manufacturer's tested thickness used to determine the maximum 75 flame spread and 450 smoke-developed index when tested to ASTM ASTM ASTM International, www.astm.org E84 or UL UL Underwriters Laboratories 723

Foam will be provided with ignition and thermal boundaries as required by code

Ensure complete and consistent coverage throughout roof plane

Eliminate cracks, gaps, and voids

Minimize framing cavity air flow

Minimize moisture migration and unwanted condensation in insulation (vapor retarders)

Ensure alignment of insulation and air barrier Air barrier The separation between the interior and exterior environments of a building that slows air flow to the point that no smoke movement is visible at 50 pascals of pressure difference across the boundary

4.1003.12g
Onsite documentation

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