1. Roof Deck Attachment

The techniques described in this and the next two steps should be used
during roof installation on both new and existing homes, and are best
performed by a licensed, professional roofing contractor.

• For new construction, install a roof deck of 5/8-inch thick plywood with 8 penny ring shank nails spaced 6 inches along the panel edges and every 6 inches in the field of the panel. Make sure the nails penetrated the decking directly into the roof framing.
• Look in the attic to confirm the roof decking is properly nailed to the roof framing. If you can see nails along the sides of rafters or trusses, where the nail penetrates the decking, your roof deck may not be securely attached.

2. Secondary Water Barrier

Even though roof coverings are somewhat wind resistant, a secondary
water barrier provides protection if the covering is damaged or blown off.

•Create a secondary water barrier by installing self-adhering flashing tape or modified polymer bitumen strips on top of the joints in your roof deck. This will help keep out the rain in the event the roof covering is damaged or destroyed by severe weather.
• Install one layer of 30# underlayment – sometimes called felt paper – over the roof decking and secondary water barrier. The felt helps with drainage in the event water gets under the roof covering.

3. Roof Covering

• Install a roof covering that has been tested to the latest standards for wind and hail resistance. These standards are: ASTM D 3161 (modified to 110 mph), ASTM D 7158 or UL 2390 for wind resistance and UL 2218 for impact resistance.
• Be sure to specify these standards and look for labels on the products confirming these standards because ordinary roofing materials may not look any different from the wind-resistant versions.

4. Gable End Bracing

The type and shape of your home’s roof can influence how well the roof
will withstand high winds. Wind pressure on a hip shaped roof is lower
than the wind pressure on a gable shaped roof in the same storm.
Homes with unbraced gable end walls are more likely to suffer damage,
such as collapse of the end wall from high winds. For gable end wall
construction, use one of the following techniques:

• Continuous Wall Construction or Balloon Framing – For new construction, use full-height studs, concrete or solid masonry walls
from the floor to the roof. Balloon-framed gable end walls perform better in windstorms because they do not have the hinge that usually exists where the triangular part of the gable sits on top of the wall below. Homes with high, cathedral-style ceilings should be balloon framed or will require a special design by a registered architect or licensed engineer.
• Platform Framing– Brace the intersection of the gable end and the end wall. This intersection is a particularly weak point and those that are not properly braced can collapse, causing major damage, allowing wind and wind-driven rain into the home. In homes with attics, an attic floor or ceiling diaphragm with the proper bracing techniques can be used to provide the lateral support of the gable end wall if the end wall is NOT framed full height.

5. Foundation-to-Wall-to-Roof Connections

Your home’s ability to resist the extreme force of wind is only as strong
as its weakest link, so the only way to create a wind-resistant home is to
secure all connections – foundation to wall, and wall to roof. To make
sure the roof stays in place when severe winds blow, securely anchor the
roof to the wall by installing hurricane straps or clips on each rafter or
truss where they meet the exterior walls. Be sure to install all connectors
following manufacturer’s specifications.

6. Protecting Openings

You can protect your home’s openings, such as windows and doors, from
windborne debris by installing impact-resistant windows and doors or
installing impact-resistant coverings, such as shutters, over windows and
doors. Impact-resistant glass and shutters are specifically designed to
meet a combination of impact and continuous pressure from wind. Always
use products that have been tested and approved to one of these standards
and have been designated as such through a recognized product
approval system or evaluation report: SSTD12; ASTM E 1886 and ASTM E
1996; or Miami-Dade Protocols TAS 201, TAS 202, TAS 203.

Equally important as the strength of the glass or shutter is the strength
of the window’s frame and attachment hardware. Impact-resistant units
are tested as a unit that includes the glass, the frame, as well as the
attachment hardware and the installation method. Impact-resistant
windows and shutters should always be installed following manufacturer’s
recommendations.

7. Garage Doors

Garage doors are particularly vulnerable to high winds because of the
long span of opening they cover and the relatively lightweight material they
are made of. Two options are available for strengthening garage doors:

• Replace the door and track with a system designed to withstand high winds and windborne debris, or
• Protect the garage door with a tested and approved impact resistant covering.