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FORTIFIED Home Sealed Roof Deck - Material Options for Taping the Roof Deck Seams

Author(s)

Insurance Institute for Business and Home Safety

Organization(s)

IBHS

Publication Date

February, 2015

Checklist providing options and a guide for taping roof deck seams.

Porches, Carports, and Deck Attachments

Guide describing how to provide a continuous load path with appropriate connectors to improve the wind resistance of attached porches, carports, and decks during high-wind events.

FORTIFIED Home Sealed Roof Deck Supplemental Deck Attachment - Using 2-Part Closed-Cell Foam Adhesive

Author(s)

Insurance Institute for Business and Home Safety

Organization(s)

IBHS

Publication Date

April, 2015

Checklist providing information on strengthening the attachment of roof sheathing and installation of a sealed roof deck system using a spray polyurethane foam adhesive.

Seal the roof deck as follows: Sweep roof decking, tape seams, and cover underlayment or roofing felt as shown.

Publication Date

Wed, 12/01/2010 - 12:00

Managing Snow Loads on Roofs and Decks

Guide describing how to construct homes and decks to manage heavy snow loads in winter weather.

Roof Deck Sheathing and Sealing for Sloped Roofs

Guide describing requirements for sheathing and sealing the roof decking in accordance with the requirements of the IBHS Fortified Home Program's Hurricane and High Wind Standards, and other roofing considerations to increase the roof's disaster resistance.

How to Install Under-Deck Drainage Systems

Publication Date

April, 2020

Author(s)

Guertin Mike

Organization(s)

Fine Homebuilding Magazine

Video presentation describing how to install water-resistant under-deck drainage systems to protect roofs and homes during high wind and moisture disaster events.

Fortified Home Roof Deck Attachment for Hurricanes

PDF

Right – Seams in the deck sheathing are sealed with tape

FORTIFIED Home Sealed Roof Deck - Installation of 2 Layers of #30 Felt as a Qualified Sealed Roof Deck System for Asphalt Shingle or Metal Roofing

Author(s)

Insurance Institute for Business and Home Safety

Organization(s)

IBHS

Publication Date

January, 2015

Checklist providing the type of roofing felt recommended by IBHS as a quilified sealed roof deck system for asphalt shingle or metal roofing.

Above Deck Rigid Foam Insulation for Existing Roofs

Guide describing the installation of insulating sheathing above the roof deck on existing homes. This retrofit assembly is appropriate for homes with conditioned attics or where the retrofit is intended to create a conditioned attic.

IBHS Fortified Home Re-Roofing Deck Replacement

PDF

IBHS Fortified Home Wood Board Roof Deck

PDF

IBHS Fortified Home Felt Underlayment Roof Deck

PDF

IBHS Fortified Home Re-Nailing Roof Deck for Hurricanes

PDF

IBHS Fortified Home Roof Deck Attachment for High Winds

PDF

IBHS Fortified Home Spray Foam Sealed Roof Deck

PDF

IBHS Fortified Home Flashing Tape Sealed Roof Deck

PDF

IBHS Fortified Home Self-Adhered Membrane Roof Deck

PDF

2x4 Raised Truss - Insulation Below Roof Deck CAD

DWG

PDF

Below Deck Spray Foam Insulation for Existing Roofs

Guide describing how to add spray foam insulation to the underside of the existing roof deck as part of the conversion of a vented attic to an unvented, insulated attic.

Lag-Bolted L Brackets for Mounting PV Panels to Roof Decking

IBHS Fortified Home Re-Nailing Roof Deck for High Winds

PDF

Wrong – The step flashing is not the required height above the roof deck

Publication Date

Tue, 02/01/2011 - 12:00

Right – The step flashing is the correct height above the roof deck

Publication Date

Tue, 02/01/2011 - 12:00

Inside FORTIFIED: Installing Sealed Roof Deck with Self-Adhered Underlayment

Publication Date

November, 2018

Video showing how to correctly install sealed roof deck with self-adhered underlayment in accordance to IBHS Fortified Home protocols.

Right – A roller helps the tape to adhere over seams in the deck sheathing

Hurricane-New Construction Roof Deck Attachment, Structural Wood Panels

IBHS Fortified Home Roof Tile Cap Sheet Sealed Roof Deck

PDF

2x10 Rafter - Insulation Above Roof Deck and In Rafter Cavity CAD

DWG

PDF

2x10 Rafter - Insulation Below Roof Deck In Rafter Cavity CAD

DWG

PDF

2x12 Rafter - Insulation Above Roof Deck and In Rafter Cavity CAD

DWG

PDF

2x12 Rafter - Insulation Below Roof Deck In Rafter Cavity CAD

DWG

PDF

FORTIFIED Home Fastening Roof Sheathing Over Existing 1x Roof Deck Boards

Author(s)

IBHS Fortified Home

Organization(s)

IBHS

Publication Date

November, 2019

Factsheet describing ways to install sheathing over existing 1x roof decking.

Right – All penetrations through the roof decking are sealed with paint-on flashing.

Publication Date

Mon, 09/30/2019 - 12:00

Roof decking has adhered radiant barrier that is perforated, in addition to the nail holes

Unvented Conditioned Attic with Spray Foam Insulation Below Roof Deck

Guide describing a method for insulating an unvented attic by spraying foam insulation along the underside of the roof deck.

Three locations and methods for installing a roof deck radiant barrier in new construction

Publication Date

Mon, 06/01/2009 - 12:00

Apply roof underlayment over roof deck and up the sidewall over housewrap

Reference

40% Whole-House Energy Savings in the Marine Climate, Volume 11

Author(s)

Baechler Michael C,

Gilbride Theresa L,

Hefty Marye G,

Cole Pam C,

Williamson Jennifer,

Love Pat M

Organization(s)

Pacific Northwest National Laboratory,

PNNL,

Oak Ridge National Laboratory,

ORNL,

U.S. Department of Energy,

DOE

Report providing builders in marine climates with guidance for building homes that have whole-house energy savings of 40% over the Building America benchmark with no added overall costs for consumers.

Publication Date

Mon, 04/23/2012 - 12:00

Install self-sealing bituminous membrane or equivalent at all valleys and roof deck penetrations

Publication Date

Tue, 02/01/2011 - 12:00

Attic ventilation can reduce the likelihood of ice dam formation by cooling the roof deck.

Publication Date

Tue, 01/01/2013 - 12:00

Roof-to-Wall and Deck-to-Wall Flashing, FEMA Technical Fact Sheet No. 5.2

Author(s)

Federal Emergency Management Agency

Organization(s)

FEMA

Publication Date

December, 2010

Fact sheet describing the importance of proper roof and deck flashing, and typical and enhanced flashing techniques for coastal homes; also published in FEMA P-499 “Home Builder’s Guide to Coastal Construction: Technical Fact Sheet Series.”

Install shingle starter strip then kick-out diverter; attach to roof deck but not sidewall

Reference

40% Whole-House Energy Savings in the Marine Climate, Volume 11

Author(s)

Baechler Michael C,

Gilbride Theresa L,

Hefty Marye G,

Cole Pam C,

Williamson Jennifer,

Love Pat M

Organization(s)

Pacific Northwest National Laboratory,

PNNL,

Oak Ridge National Laboratory,

ORNL,

U.S. Department of Energy,

DOE

Report providing builders in marine climates with guidance for building homes that have whole-house energy savings of 40% over the Building America benchmark with no added overall costs for consumers.

Publication Date

Wed, 09/01/2010 - 12:00

Wrong - Roof deck sheathing nails missed the trusses, potentially weakening the roof in high winds.

Publication Date

Sun, 03/07/2021 - 12:00

This roof was insulated above the roof deck with 5.5 inches (R-38.5) of closed-cell spray foam.

The components of a roof include the rafter framing or trusses, purlins, plywood roof decking, underlayment, and the roof covering.

Publication Date

Tue, 01/01/2019 - 12:00

Right - A lattice of 1X4 furring strips provides a ventilation gap between the decking and metal roofing for this shed roof.

Publication Date

Sun, 05/16/2021 - 12:00

Spray foam insulation was installed on the underside of the roof deck and on gable end attic walls to create an unvented attic

Publication Date

Fri, 10/15/2021 - 12:00

FORTIFIED Home Installation of 2 Layers of #30 Felt as a Qualified Sealed Roof Deck System for Asphalt Shingle or Metal Roofing

Author(s)

Insurance Institute for Business and Home Safety

Organization(s)

IBHS

Publication Date

January, 2015

Checklist providing information on how and when to install solid sheathing over spaced deck boards on homes located in areas that use the FORTIFIED Home™–High Wind standards.

FORTIFIED Home ASTM D6757 - An Alternative to #30 Felt Underlayment: Sealed Roof Deck Underlayment Alternative

Author(s)

Insurance Institute for Business and Home Safety

Organization(s)

IBHS

Publication Date

February, 2019

Fact sheet describing the acceptable underlayment alternatives including ASTM D6757 Underlayment Felt Containing Inorganic Fibers for Steep-Slope Roofing for certain applications.

Right - This shed roof is constructed with 1X4 furring strips installed over the decking and underlayment for ventilation beneath the metal roofing.

Publication Date

Sun, 05/16/2021 - 12:00

Step 1. Apply roof underlayment over roof deck and up the sidewall over the rigid foam insulation

Reference

40% Whole-House Energy Savings in the Marine Climate, Volume 11

Author(s)

Baechler Michael C,

Gilbride Theresa L,

Hefty Marye G,

Cole Pam C,

Williamson Jennifer,

Love Pat M

Organization(s)

Pacific Northwest National Laboratory,

PNNL,

Oak Ridge National Laboratory,

ORNL,

U.S. Department of Energy,

DOE

Report providing builders in marine climates with guidance for building homes that have whole-house energy savings of 40% over the Building America benchmark with no added overall costs for consumers.

Publication Date

Wed, 09/01/2010 - 12:00

Wrong – Roof underlayment is not fully adhered and roof deck seams are not sealed so roof is susceptible to high-wind events

Right – Roof underlayment is fully adhered and roof deck seams are sealed so roof is resistant to high-wind events

There are three potential locations for an attic radiant barrier – adhered to the underside of the roof decking, hanging from the rafters, or on the ceiling insulation

Publication Date

Wed, 06/01/2005 - 12:00

Low-slope roof assemblies constructed of two deck sheathing layers sandwiching rigid foam, and topped with mechanically fastened membrane

IECC Climate Zone 2A: Unvented Attic with Spray Foam at Roof Deck, 2x6 Wall/CMU Wall, Elevated Slab

Publication Date

Wed, 10/18/2023 - 12:00

IECC Climate Zone 2A: Unvented Attic with Spray Foam at Roof Deck, 2x6 Wall/CMU Wall, Elevated Slab

Publication Date

Wed, 10/18/2023 - 12:00

Detail of an unvented cathedralized attic showing air-impermeable spray foam insulation plus batt insulation installed on the underside of the roof deck.

2021 IECC Climate Zone 2A: Unvented Attic with Spray Foam at Roof Deck, 2x6 Wall-CMU Wall, Elevated Slab

Publication Date

Thu, 01/11/2024 - 12:00

The attic is sealed and insulated along the underside of the roof deck with 5.5 inches of polyurethane spray foam, providing conditioned space for the HVAC system.

Sloped roof with cavity spray foam insulation sprayed on underside of roof deck and covered with sprayed-on thermal or ignition barrier coating.

Publication Date

Fri, 05/01/2015 - 12:00

Right – The roof membrane is fully adhered and deck seams are sealed so the membrane will not flutter and fail due to negative pressure from high winds

Right – Closed-cell polyurethane foam is sprayed on the underside of the roof deck to provide structural connections and seal seams in the sheathing to increase wind resistance

A roof drain is installed in an existing flat roof retrofitted with above-deck rigid foam insulation that is integrated with new air and water control layers

Publication Date

Thu, 09/10/2015 - 12:00

On top of the ice-and-water shield, the builder installed horizontal beams that were raised 6 inches off the deck to allow room for spray foam insulation.

Spray foam insulation is applied along the underside of the roof deck to provide a conditioned and non-vented attic space for ducts and air handlers.

Reference

40% Whole-House Energy Savings in the Hot-Humid Climate, Volume 15

Author(s)

Baechler Michael C,

Gilbride Theresa L,

Hefty Marye G,

Cole Pam C,

Adams Karen T,

Noonan Chrissy F,

Love Pat M

Organization(s)

Pacific Northwest National Laboratory,

PNNL,

Oak Ridge National Laboratory,

ORNL,

U.S. Department of Energy,

DOE

A guidebook helping builders in hot-humid climates design and construct homes for energy efficiency, durability, health, safety, and comfort.

Publication Date

Thu, 09/01/2011 - 12:00

Step and kick-out flashing at all roof-wall intersections extending ≥ 4 in. on wall surface above roof deck and integrated with drainage plane above

Publication Date

Tue, 02/01/2011 - 12:00

The mechanical curb for a skylight is integrated with the water management and air control layers on a flat roof retrofitted to include new above-deck rigid foam insulation

Publication Date

Fri, 05/01/2015 - 12:00

Wrong - Roof is missing metal drip edge to cover the edge of OSB roof decking, roof underlayment should be trimmed back, and asphalt shingles are poorly installed.

Publication Date

Mon, 09/28/2020 - 12:00

Unvented roof assembly at rake retrofitted with spray foam installed along the underside of the roof deck and extended to the rake edge to insulate and air seal the attic

Publication Date

Mon, 07/01/2013 - 12:00

Right - Metal drip edge on this south Florida CMU home protects the top of the fascia and edge of the roof deck from water, wind-blown rain and embers, and insects.

Publication Date

Tue, 06/01/2021 - 12:00

To reduce the risk of condensation on the interior of the roof sheathing in cold weather, the ratio of exterior (above-deck) insulation must be increased as a percent of total attic insulation as outside temperature decreases

Publication Date

Sat, 10/01/2011 - 12:00

This roof is hurricane proofed with a coated insulated OSB deck sheathing that is caulked and taped at all seams with a water-resistant tape, then fully covered with a peel-and-stick membrane, and asphalt shingles.

Wrong – If roof membrane is not fully adhered, it can flutter and fail due to negative pressure from wind above and positive pressure from air leakage through roof deck below

The icicles and the bare spot along the left roof ridge indicate that heat from the second-story room may be heating the underside of the roof deck, melting the snow and likely leading to ice dam formation.

Publication Date

Mon, 10/30/2006 - 12:00

In 2009 IECC CZ 5 and higher, install self-sealing bituminous membrane or equivalent over sheathing at eaves from the edge of the roof line to > 2 ft. up roof deck from the interior plane of the exterior wall.

Publication Date

Tue, 02/01/2011 - 12:00

The OSB roof decking product comes with an adhered radiant foil barrier which helps to prevent heat transfer in or out of the vented attic, while R-13 unfaced fiberglass fills the advanced-framed 2x6 walls.

Retrofit an existing roof by installing rigid foam above the roof deck with a ventilation space between the rigid foam and the new roof sheathing plus new moisture and air control layers and cavity insulation in the roof rafters.

The simple gable roof is constructed at an unusual 6.55 pitch that allows exactly four and a half sheets of 4-foot- wide coated, taped roof sheathing to be installed as the roof deck with enough space at the peak for a continuous ridge vent.

This roof was constructed to meet the IBHS Fortified Roof standard by sealing the decking seams with flashing tape, installing synthetic roof underlayment secured with metal drip edge and nailed every six inches, and using self-adhered starter shingles.

Publication Date

Thu, 08/17/2023 - 12:00

The existing 2x8 roof rafters were topped with OSB; two layers of 2-inch rigid foam; plywood; ice and water shield at rakes, eaves, and valleys; underlayment; and fiberglass shingles, plus 6 inches of open-cell foam under the decking.

Wrong – This roof membrane on a low slope roof is fluttering and may fail because it is not fully adhered and deck seams below are not sealed, allowing air to leak up into the assembly while the membrane is pulled up due to negative pressures from wind

Animated video showing how to properly apply roof decks in hurricane regions according to IBHS practices.

Inside FORTIFIED: Sealing Roof Seams with Tape

Publication Date

May, 2018

Video showing how to seal the roof deck with tape per IBHS Fortified Requirements.

Framing of Gable Roof Overhangs

Guide describing construction of gable roof overhangs to resist uplift pressures in high winds.