ROOF SYSTEM RETROFITS Roof System Retrofit 1: Roof-to-Wall Connections The roof-to-wall retrofit strengthens the connection of the roof rafters to the walls to withstand negative (suction) pressures created by high winds. Contractors install metal clips to connect the rafters and trusses to the top plate of the outer wall. In the majority of cases, construction will entail removing the exterior soffit (the exposed undersurface of the roof overhang) to allow access to the roof-to-wall connection area. In rare cases, approximately 12 inches of the exterior siding may be removed in addition to the removal of the soffit. The post-inspection Homeowner Report will describe the type of access required for each home. Once the clips are installed, any reusable soffit material removed to allow access to the roof-to-wall connection will be re-installed. Any soffit material not reusable will be replaced with new material. When installing new material, reasonable effort will be made to match previous soffit material; however, slight variations should be expected. For non-vinyl soffits, one coat of primer will be applied to all new material. One coat of color paint will be applied to all new material if the homeowner provides color paint by the start of construction. Any noticeable changes to the appearance of the home will be due to variations between any new and old soffit material and the change in soffit color, if the homeowner chooses not to provide color paint. Homeowners should remove items from under the eaves of the house, such as lawn ornaments and furniture obstructing access to the eaves anywhere along the exterior walls of the house. During construction, occupants of the home should expect the normal inconveniences of a construction site comparable to having new siding or a new roof installed. This retrofit will typically take 2 - 5 days to install. Figure 1. Roof-to-Wall Connection Figure 2. Roof-to-Wall Connection 1 of 16
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ROOF SYSTEM RETROFITS
Roof System Retrofit 1: Roof-to-Wall Connections
The roof-to-wall retrofit strengthens the connection of the roof rafters to the walls to withstand negative (suction) pressures created by high winds. Contractors install metal clips to connect the rafters and trusses to the top plate of the outer wall. In the majority of cases, construction will entail removing the exterior soffit (the exposed undersurface of the roof overhang) to allow access to the roof-to-wall connection area. In rare cases, approximately 12 inches of the exterior siding may be removed in addition to the removal of the soffit. The post-inspection Homeowner Report will describe the type of access required for each home.
Once the clips are installed, any reusable soffit material removed to allow access to the roof-to-wall connection will be re-installed. Any soffit material not reusable will be replaced with new material. When installing new material, reasonable effort will be made to match previous soffit material; however, slight variations should be expected.
For non-vinyl soffits, one coat of primer will be applied to all new material. One coat of color paint will be applied to all new material if the homeowner provides color paint by the start of construction. Any noticeable changes to the appearance of the home will be due to variations between any new and old soffit material and the change in soffit color, if the homeowner chooses not to provide color paint.
Homeowners should remove items from under the eaves of the house, such as lawn ornaments and furniture obstructing access to the eaves anywhere along the exterior walls of the house. During construction, occupants of the home should expect the normal inconveniences of a construction site comparable to having new siding or a new roof installed. This retrofit will typically take 2 - 5 days to install.
Roof System Retrofit 2: Collar Tie/Ridge Board Connection
The collar tie retrofit strengthens the rafter-to-ridge board connection to withstand negative (suction) pressures created by high winds. Contractors will install 2x6 wood collar ties in the attic near the ridge board, as pictured below. Houses with existing collar ties may still require this retrofit depending on the capacity of the existing tie. The capacity of existing collar ties will be determined during engineering analysis using data collected during the initial inspection. To install the collar ties, contractors will require access to the attic. This retrofit will not cause any noticeable changes to the overall appearance of the home.
Homeowners should remove any fragile or large storage items to provide unobstructed workspace along the center of the attic. This retrofit will typically take 1 day to install.
The hip rafter connection retrofit strengthens the connection of the hip rafters to the jack rafters to help withstand negative (suction) pressures created by high winds. Nails or metal clips are added inside the attic to each hip rafter and jack rafter connection. To install this retrofit, contractors will require access to the attic. This retrofit will not cause any noticeable changes to the overall appearance of the home.
Homeowners should remove any fragile or large storage items to provide unobstructed workspace in the attic. This retrofit will typically take 1 day to install.
Jack Rafter Common Rafter
Hip Rafter
Figure 5. Hip Rafter Connection
Figure 6. Hip Rafter Connection
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Roof System Retrofit 4: Gable End Bracing
The gable end bracing retrofit strengthens the gable ends to withstand pressures created by high winds. Braces are installed in the attic to strengthen the gable end wall and the connections between the gable, roof structure and the exterior walls. Depending on the existing framing, stiffeners, cross braces and/or strong-backs will be installed. To install this retrofit, contractors will require access to the attic.
Homeowners should remove any fragile or large storage items to provide unobstructed workspace in the attic. This retrofit will not cause any noticeable changes to the overall appearance of the home. This retrofit will typically take 1 - 2 days to install.
Figure 7. Gable End Cross Braces Figure 8. Gable End Strong-back Bracing
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Roof System Retrofit 5: Soffit Protection
In the event of hurricane force winds, adequate soffit protection prevents water from entering the attic and the structure below. Hurricane force winds usually cause failure of soffits by blowing the soffit material away from the structure. High winds then force rainwater into the attic space through the open soffit and damaging the insulation and ceilings. The soffit retrofit protects the exposed undersurface of the roof overhang along the drip edge of the roof. This retrofit does not include gable- end overhangs
This retrofit will install one or more of the following depending on the existing soffit conditions: stronger soffit material, additional framing, and/or additional fasteners. Any adequate existing soffit material will be reused if it was not significantly damaged during removal. Any soffit material not reusable will be replaced with new material. When installing new material, reasonable effort will be made to match previous or existing soffit material; however, slight variations should be expected. The preexisting venting scheme will be followed when installing new plywood and cement board. One coat of primer will be applied to all new plywood and cement board. One coat of color paint will be applied to new plywood and cement board if the homeowner provides color paint at the start of construction. Any noticeable changes to the appearance of the home will be due to variations between the new and old soffit material and the change in soffit color if the homeowner chooses not to provide color paint.
The soffit retrofit ensures there is adequate backing behind vinyl soffit material and vinyl porch ceilings. The backing protects the attic from wind and water if the vinyl is blown away during high winds. If the soffit or porch does not have backing behind the vinyl or needs more substantial backing, the vinyl will be removed and OSB board or plywood will be installed on the soffit or porch. Additional framing may be added and/or existing backing re-nailed as needed. The original vinyl material will be reinstalled over the backing. Openings will be cut into backing material at appropriate locations to provide soffit venting.
This retrofit usually requires 2 - 3 days for installation, and is installed in conjunction with the Roof-to- Wall retrofit, if that retrofit is needed. Homeowners should remove any items from under the eaves of the house, such as lawn ornaments and furniture, which would obstruct access to the eaves anywhere along the exterior walls of the house. During construction, occupants of the home should expect the normal inconveniences of a construction site comparable to having new siding or a new roof installed. This retrofit usually requires 2-3 days for installation and is installed in conjunction with the Roof-to-Wall retrofit, if that retrofit is needed.
The roof deck attachment retrofit strengthens the connection of the roof deck to the roof rafters to help withstand the pressures created by high winds. This entails applying adhesive foam along the inside edge of each rafter where it meets the roof decking. The adhesive foam bonds the rafters and roof decking together and helps prevent the roof decking from peeling away during high winds. Horizontal seams in the roof decking are also sealed with the foam. This provides a secondary water barrier to help reduce water damage to the home in the event the shingles are blown off the roof.
Since the retrofit is installed in the attic, there will not be any noticeable changes to the appearance of the home. Homeowners must remove any fragile or large storage items to provide unobstructed workspace throughout the entire attic. Small foam droplets may settle on anything left in the attic. This retrofit will typically take 1-2 days to install.
Figure 11. Roof Deck Attachment
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OPENING RETROFITS
Existing Protection
There are many “hurricane rated” shutters, doors and windows available which offer various levels of protection. Any previously installed shutters, doors and windows will be examined to ensure the products provide adequate protection, and to ensure they were installed correctly. Any openings inadequately protected will receive protection, such as shutters, replacement doors or skylights, depending on the type of opening.
The products used in this project have been independently tested to national standards and are approved by the Florida Building Commission and/or Miami Dade County. As part of the engineering process, engineers select shutters and doors that offer adequate levels of protection for the unique requirements of each home.
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Opening Retrofit 1: Window Protection
The window protection retrofit provides metal panel shutters for all windows reducing window breakage, water intrusion and internal pressures caused by windborne debris and high winds.
The standard window protection retrofit includes metal panel shutters. Other types of shutters, such as accordion, bahama, roll-down and fabric, are considered upgrades from the standard package. If an upgrade is desired, the homeowner must pay the entire difference in cost. The FEMA match is not available for the difference in cost for upgrade shutters. The initial Homeowner Report will include costs for panel shutters. A shutter installer will conduct a follow-up inspection to determine the cost of upgrades, if desired.
The metal panel shutters are manufactured from galvanized steel or aluminum. Due to the sectional design and lighter weight, many people find installing the metal panel shutters much easier than installing plywood over windows. As the name implies, panel shutters are comprised of several 16-inch wide corrugated metal panels. These panels are installed one at a time and weigh approximately 4-7 pounds each, depending on the size of the window. Depending on the height of the window, a ladder may be required to install the metal panel shutters.
While metal panel shutters are designed for temporary use, the shutter’s fastening hardware is permanently installed. A variety of fastening hardware is used to attach panel shutters, depending on the type of window and siding surrounding the window. For brick siding, shutters are typically mounted horizontally, and fastened using hand tightened wing nuts over threaded studs that remain in place. Windows surrounded by wood or vinyl siding typically require a track along the top and bottom edges of the window. The shutters are placed in the tracks and fastened with hand-tightened wing nuts.
This retrofit will typically take 2 - 5 days to install.
The entry door protection retrofit includes panel shutters for all but one exterior door (see description of panel shutters under window protection). To provide a means of egress, one door will receive a shutter operable from inside the home or be replaced with a hurricane resistant door. An accordion shutter is one of two possible operable shutters. The accordion will be installed if the door selected as an egress door swings in, allowing the shutter to be opened and closed from inside the home. If an accordion cannot be installed on the house, then a roll-down will be installed if there is enough room above the door for the shutter. The roll-down shutter can be opened and closed using a crank handle from inside the home.
If an accordion or a roll-down cannot be installed, then the door will be replaced with a hurricane resistant door. This requires removing the existing exterior door and door frame and replacing it with a hurricane resistant door and frame assembly. The existing hardware (door knob and dead bolt) is usually adequate and can be reused in the new door. The CRM project does not provide door hardware or change door locks. Homeowners should supply hardware if the existing door knob or deadbolt is missing or inadequate.
The post-inspection Homeowner’s Report will identify which door has been designated as the egress door and whether the door will receive a roll-down shutter, accordion shutter or be replaced with a hurricane resistant door. This retrofit will typically take 1 day to install.
Garage doors are particularly vulnerable to failure due to windborne debris. Once the exterior of a home is breached during a hurricane, the internal pressure builds up inside the home and increases the likelihood of roof failure.
Existing garage doors will be examined to ensure they provide adequate protection, and to ensure they were installed correctly. Any inadequate doors will be replaced or receive a fabric shutter - whichever is more economical. The cost of the Garage Door retrofit is based on the size of the garage door, and the type of door needed to withstand expected wind pressures. The post-inspection Homeowner’s Report will indicate whether or not existing garage doors will be replaced or receive a shutter.
The replacement garage doors are both impact and pressure rated. They and operate like a normal door and the existing garage door opener will be adequate to operate the new door. Replacement doors with impact resistant windows are available as an upgrade.
The fabric shutter for a garage door is a single piece, of pliable, yet extremely strong fabric that can be rolled or folded for storage. Construction entails installing fasteners on the outside of the wall either in the mantel over the door and in the concrete threshold, or along both upright sides of the door. The fastener spacing ranges from a few inches to 12 inches apart. To put up the shutter, homeowners secure the fabric to the fasteners in the wall using hand tightened washer-wing nuts.
Prior to construction, homeowners must remove any items blocking access to the garage door rails. This retrofit will typically take 1-2 days to install.
Figure 18. Garage Door Replacement
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Opening Retrofit 4: Skylight Protection
New skylights fitted with impact resistant glass and stronger frames will replace any non impact rated skylights. These features allow the skylights to withstand high winds and impact from windborne debris. Regular skylights are especially vulnerable to failure due to impact. Once a skylight is broken and the exterior of the home is breached, internal pressure builds up and increases the likelihood of roof failure. Significant water damage is also caused by a skylight failure. Construction will involve removing all existing, non-impact rated skylights and replacing them with hurricane resistant skylights. During skylight replacement, some shingles must be removed. Any reusable shingles will be reused. Any shingles not reusable will be replaced with new shingles. When installing new shingles, reasonable effort will be made to match previous shingles; however, slight variations should be expected. This retrofit will typically take 1-2 days to install.
Figure 19. Skylight Protection
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IBHS BRONZE RETROFITS
IBHS Bronze Retrofit 1: Secondary Water Protection
Secondary water protection prevents water intrusion if the shingles or other primary roof covering are blown away or damaged. This is achieved by applying adhesive foam in the attic against the underside of the roof decking. All roof decking seams are sealed with the adhesive foam. The foam cannot be installed in areas where vaulted ceilings prevent access to the roof deck in the attic. If one area of the roof is inaccessible, the Secondary Water Protection retrofit will not be installed because the roof deck is not able to be fully protected.
Any existing secondary water protection will be considered during engineering analysis to ensure it provides adequate protection and was installed correctly. Common vapor barriers, such as tar paper or felt, do not provide protection from water intrusion if the shingles are blown off. These are not considered secondary water protection.
Since the retrofit is installed in the attic, there will not be any noticeable changes to the appearance of the home. Homeowners must remove any fragile or large storage items to provide unobstructed workspace throughout the entire attic. Small foam droplets may settle on anything left in the attic. This retrofit will typically take 1-2 days to install.
Note: Houses requiring the Roof Deck retrofit will not require the Secondary Water Protection retrofit because the Roof Deck retrofit naturally provides a secondary water barrier.
Figure 20. Secondary Water Protection
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IBHS Bronze Retrofit 2: Ridge and Off-Ridge Vents
Strong winds can force rain water into the attic through the roof vents, soaking the insulation and drywall below. To reduce water intrusion, the ridge and off-ridge vents will be replaced with high wind- rated products which are resistant to water intrusion. These vents allow air movement during normal conditions. All existing ridge and off-ridge vents will be replaced with wind-rated products. This does not include installing vents where none already exist. Off-ridge vents include power vents, box vents and turban vents. Reasonable effort will be made to match the style and color of existing vents. However, variations should be expected due to product availability and fading.
Some shingles around the existing vents may be replaced with new shingles when the new vents are installed. The new shingles will be the best match of the previous color and style. However, slight variation should be expected due to product availability and fading.
Figure 21. Power Vent Figure 22. Box Vent
Figure 23. Ridge Vent
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IBHS Bronze Retrofit 3: Gable End Vents
To prevent water intrusion through the gable end vents caused by high winds, shutters will be provided for all gable end vents. This requires installing tracking above and below the vent or threaded studs, depending on the siding type. Removable shutters are installed by the homeowner in the tracks or threaded studs in order to close off the vents in the case of high winds. The shutters used for the gable end vents are similar to the window and door shutters. Shutters are either fabric or metal panel shutters.
Figure 24. Gable End Vent
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IBHS Bronze Retrofit 4: Gable End Overhang
Gable end overhangs are vulnerable to uplift failure because they collect the wind load from above and below the overhang. The Gable End Overhang retrofit also reduces wind and water intrusion into the attic by strengthening the soffit material and attachment, if needed. Each overhang will be analyzed during engineering analysis to determine if strengthening is required. Inadequate overhang framing and soffits will be retrofitted.
To strengthen the overhang to resist the uplift forces, blocking and clips will be added in the attic and in gable end overhangs. Typical blocking spacing ranges from approximately 12” to 24”. Installing the clips and blocking will entail removing the overhang soffit, installing the blocking and clips then replacing the overhang soffit.
To reduce wind and water intrusion, one or more of the following will be installed, depending on the existing soffit conditions: stronger soffit material, additional framing, and/or additional fasteners. Any adequate existing soffit material will be reused if it was not significantly damaged during removal. Any soffit material not reusable will be replaced with new material. When installing new material, reasonable effort will be made to match previous or existing soffit material; however, slight variations should be expected. The preexisting venting scheme will be followed when installing new plywood and cement board. One coat of primer will be applied to all new plywood and cement board. One coat of color paint will be applied to new plywood and cement board if the homeowner provides color paint at the start of construction. Any noticeable changes to the appearance of the home will be due to variations between the new and old soffit material and the change in soffit color if the homeowner chooses not to provide color paint.
The Gable End Overhang retrofit ensures there is adequate backing behind any vinyl soffit. The backing protects the attic from wind and water intrusion if the vinyl is blown away during high winds. If the soffit does not have backing behind the vinyl or needs more substantial backing, OSB board or plywood will be installed on the soffit. Additional framing may be added and/or existing backing re-nailed as needed. The original vinyl material will be reinstalled over the backing. Openings will be cut into backing material at appropriate locations to provide soffit venting.
This retrofit usually requires 2-3 days for installation. This retrofit protects the gable-end overhangs. It does not include the roof overhang along the drip edge of the roof. Any noticeable changes to the appearance of the home will be due to variations between the new and old soffit material and the change in soffit color if the homeowner chooses not to provide color paint. Homeowners must remove any large storage items from around the gable ends to provide unobstructed access to the gable ends.
During construction, occupants of the home should expect the normal inconveniences of a construction site comparable to having new siding or a new roof installed. Homeowners must remove any large storage items from around the gable ends and from under the eaves of the house to provide unobstructed access to the gable ends. This retrofit usually requires 2-3 days for installation.
