When the outer shell of a house is damaged, it becomes prone to sudden collapse.
For example, if a door facing the wind blows in, the full force of the storm will hit the interior. Needing somewhere to go, the wind will then rip out windows, doors, walls or the roof. Even a small breach such as a roof tile bursting through a window, can have the same effect. Therefore pay special attention to all exterior openings.
Storms often get a finger into the house through the roof if it not secure.
The wind begins to peel away the roofing material at the gable ends or eaves, exposing the edges of the roof sheathing. The sheathing then becomes damaged and the ceiling gets soaked and collapses, allowing wind and water inside. While the structure may survive, the interior and its contents will likely be destroyed.
For homes already built:
- Check roof structure to see if it is reinforced with hurricane straps. Hurricane straps anchor the wood frame of the roof to the walls, helping to keep the roof on during high winds. If you have a gable-end roof, make sure it is properly braced at the ends. Attach 2x4 or 2x6 planks to the gable end, at right angles to the truss system. Screws, not nails, should be used to attach the braces since screws are harder to pull loose. Consider having an experienced builder or engineer check your roof and do the necessary repairs and installing of hurricane straps. It is worth the investment. If you live in rented accommodation, ask your landlord about this.
- Replace roof covering that is cracked, rusted, loose or brittle. If you are replacing roof covering, consider metal roofing or asphalt shingles instead of roof tiles. Standing seam roofs do well if they are crimped together, using the manufacturer’s recommended machines. Correctly-attached asphalt shingles will also perform well. (See box information on installing asphalt shingles.)The roof will peel away if it is not properly installed. Roof tiles can cause a lot of damage when they go air-borne and need very careful installation.
- When replacing or repairing corrugated zinc roof, 1x4 battens should be spaced at 16 inches on center and fixed to each rafter with two 12-guage 2 ¾ inch galvanized wood screws. Battens should be doubled near the ridge and eaves. Nail the sheets with 10 penny ring shank nails at six inches on centres or eight-gauge galvanized screws at six inches on centres. Nails or screws should have a rubber gasket to seal the roof.
- New corrugated zinc roof should be placed over solid plywood sheathing with a layer of 30# felt or other approved water barrier. Sheets should be fastened with 10 penny ring shank nails at six inches on centres or eight-gauge galvanized screws at six inches on centres. Nails or screws should have a rubber gasket to seal the roof.
- Check double entry doors. Secure the inactive door to the header and thresholds by adding reinforcing pins to the top and bottom of the door as well as by adding heavier hinges and more secure locks.
- Make sure door and window frames are securely fastened to their rough framing and check that the header is held in the wall with steel strapping and not just a couple of nails.
- Double garage doors are another weak point because they tend to wobble as high winds blow. These doors can pull out of their tracks or collapse from the wind pressure. Install bracing horizontally across the door. This can be done anytime as the bracing can remain on the doors year round. Use six to eight 2x4s or steel supports for this.
- Shutters are the most effective protection for all windows, French, and sliding doors. The best option is to install shutters bolted to the walls as strong winds tend to rip off plywood, roll-down, and louvered aluminium
shutters. However, homemade plywood shutters, if installed properly, can offer a high level of protection. (See information on plywood and commercial shutters.) Remember to cover any vents on the gable ends of your roof if you have a gable-end roof.
Building a home? Now’s the time to make it hurricane proof.
- Because of their shape, properly constructed hip roofs can withstand hurricane winds better than gable end roofs. This is because all surfaces of the hip roof are sloping, allowing wind to flow around them, whereas gable ends are vertical, which allows the force of the wind to constantly build up against them. If you are building a gable end roof it is crucial to makesure that it is properly braced.
- Make sure your builder installs hurricane straps wherever roof beams join each other or join the walls.
- Ensure that exterior doors open outwards. It is harder for them to blow in.
- For windows, French or sliding doors, choose an impact-resistant glazing such as laminated glass or install hurricane-rated shutters.
- When installing a garage door, buy a specially reinforced one and have it installed by a professional.
Terms to Know:
- Header – the crosswise piece at the top of the door of the door frame
- Threshold – A strip of wood or other material at the bottom of the doorway
- Reinforcing pin – pointed metal fasteners that will keep door in place
- Rough framing – the grid that holds the window/door in the wall
- Steel strapping – narrow steel strips used to secure door and window headers
- Bracing - reinforcing
- 2x4s - wood in lengths that are 10 cm wide and 5 cm thick (4 in. wide and 2 in. thick.) It is the standard material for buildings of wood-frame construction.
- French doors (also called French windows) – double doors made of glass panels, usually opening onto a covered patio or verandah.
- Louvered shutters – Shutters with horizontal slats angled to admit air and light but not rain
- Masonry anchors – the bits used to secure screws in concrete walls
- Washers –a small disk or ring used to keep a screw or bolt secure or prevent leakage at a joint
- Glazing – glass that has been installed in windows or doors
- Impact-resistant glazing – reinforced glass manufactured to withstand the impact of flying debris
- Laminated glass – glass coated with plastic or other substance to make it more impact-resistant
- Hurricane straps – Metal strips which are bent over the truss beams and embedded in the concrete tie beam/belt beam. They anchor the roof to the house and the trusses to the wall helping to keep the roof on in high winds.
Installing Shingles
Most roofs in Cayman are covered with shingles and these can hold up well against high winds when properly installed. You should either use a certified contractor to do roof repairs when or read the manufacturer’s instructions carefully as there are many different brands of shingles that might have different ways of installation. For example, some brands of shingles have an adhesive strip that will give the shingles extra staying power. You should be sure to follow the manufacturer’s instructions on whether to remove the protective piece of cellophane paper from the shingle before installing it. For some brands, failing to do so will undermine the shingles’ ability to stick, making them vulnerable in high winds. The heat of the sun activates the adhesive, but it needs time to cure.
Other things that will make shingle replacement easier are taking down the old shingles when it is cooler – in the mornings or early evening – and installing the new shingles when the sun is out, as shingles are more pliable when they are hot. A flat felt surface also makes installation easier. The US Asphalt Roofing Manufacturers Association recommends that asphalt shingles should be glued to the drip edges with roofing cement along the eaves and the gable ends. The exposure of shingles should also be reduced to four inches and the shingles should be attached with six nails instead of the usual four. Nails should be used instead of staples when installing shingles as overdriven staples can pass right through the shingles. All flashings should be cemented down and nailed on four-inch centres. When installing shingles pay special attention to type composition and spacing of nails; proper nailing patterns and overlapping of shingles. Remember that all roofing material will degrade over time making it more vulnerable to a storm as time passes.
Shuttering
Covering your windows and doors properly is one of the most important things to do when a storm is coming. The aim is to protect your house from wind and prevent flying objects crashing through the windows/doors into the building as this will not only allow rainwater into your home, but increases the chance of your roof blowing off. You can buy either ready-made shutters or plywood sheets. Remember though: No covering will compensate for a
poorly built house, or an unprotected garage.
Effective Plywood Shutters:
- Plywood should be at least 5/8 of an inch thick and must be properly attached to the building in order to work. Even the best-designed shutter will fail in strong winds if not installed properly.
- For windows, use plywood that is at least 5/8 of an inch thick. Large openings such as glass doors need at least 3/4-inch thick plywood.
- Mark each sheet so that you will know what opening it is for.
- Practice installing the sheets at the start of the hurricane season.
- Store the sheets with the nails, screws or other hardware you will need to install them. Caution! Some people cut the plywood and attach it in the inset of the window, against the window frame. However, in many homes, the window frame itself is not attached firmly enough to the surrounding wall and in high winds the added force of the plywood against the window frame could cause the entire window to blow out, frame and all! You shouldn’t rely on the window frame to hold the plywood in place.
Installing plywood covering:
- Use 4- or 6-penny masonry nails to nail the plywood to the wall around the window.
- The nails should be inserted at 1-foot intervals all around the edge of the plywood sheet.
- On large openings, where a window or door is larger than the plywood sheet, use two sheets side by side. Nail a 2x4 or 2x6 plank of lumber across the line where the two pieces join. This strengthens the junction.
- Sliding glass patio doors: If there is no wall below the sliding doors to nail the bottom edge of the plywood to, secure that section by a length of timber (2x4 or 2x6) nailed across the bottom edge of the plywood and secured to the floor.
- Garage doors: Many garage doors can not withstand hurricane winds unless they are strengthened. Brace them from the inside with 2x4 or 2x6 wooden beams, running lengthwise.
Remember! When a hurricane warning is issued stores will quickly run out of plywood supplies. If you do not prepare beforehand, you might not be able to get any plywood on the day before a hurricane strike.
Commercial Shutters
Listed below are the most popular types of commercial shutters with the advantages and disadvantages of each.
Storm Panels:
These steel or aluminum shutters attach to the walls around windows and doors on bolts or tracks. The biggest problem with storm panels is that homeowners often don’t check them when they buy a home. Many discover later that panels are missing or were cut improperly, or are too heavy to install themselves.
Pros
- Most inexpensive of the permanent shutter systems.
- Removable, so they don’t change the look of the house when not in use
- Strong, and can provide excellent protection for both doors and windows.
Cons
- Require storage, but usually stack together tightly and take up little space.
- Can be difficult to handle; hanging can require more than one person.
- Sometimes don’t line up properly.
- Have sharp edges.
- Average storm preparation time: 15 minutes per window depending on the style
Roll-Down Shutters:
These shutters attach above the window. They roll up and store in an enclosed box when not in use.
Pros
- They are permanently affixed beside the windows and don’t require any extra storage space.
- They can easily be made storm-ready by one person.
- They offer some of the best protection, and make an excellent theft deterrent.
Cons
- They are the most expensive of the popular shutter systems.
- Push-button-operated, roll-down shutters require a battery backup system so that the shutters can be lowered and raised during power outages
- Average storm preparation time: Minimum - probably the easiest shutter to operate.
Accordian Shutters:
These one- or two-piece shutters are housed beside the windows of doors when not in use.
Pros
- They are permanently affixed beside the windows and don’t require any extra storage space.
- They can easily be made storm-ready by one person.
- Some models can be locked with a key and may be used as a theft deterrent
Cons
- These shutters can look bulky and out-of-place on some houses. Consider the aesthetics before having them installed
- They glide on wheels, and have the potential to break more easily than some of the other systems.
- Average storm preparation time: 15 -30 minutes for an entire house.
Colonial Shutters:
These are two-piece louvered shutters that attach to the wall beside each window
Pros
- They are permanently affixed beside the windows and don’t require any extra storage space.
- They can easily be made storm-ready by one person.
- Colonials are decorative; they can beautify as well as protect your home.
Cons
- Some types of colonials require a storm bar or centre rod to lock the shutters in place. This can increase installation time.
- They can’t be used to protect doors, and must be combined with another shutter system to ensure complete home protection.
- Average storm preparation time: 15-30 minutes for an entire house.
Bahama Shutters:
These one-piece louvered shutters attach directly above the windows and prop open to provide shade for the window.
Pros
- They are permanently affixed beside the windows and don’t require any extra storage space.
- They can easily be made storm-ready by one person.
- They provide permanent shade and privacy, even in the open position.
Cons
- These shutters have traditionally been weaker than other systems, but the newest models protect well.
- Some people complain they block too much light.
- Their design limits their use. They can’t be used to protect doors.
- Average storm preparation time: 15-30 minutes for an entire house.
Other Types of Commercial Coverings Include:
- Hurricane-proof glass -This has a special film attached to the glass’ surface, or a special material bonded between two panes of glass to make one thick pane. The glass is then mounted into the window or door
frame. - Storm shields – These resemble thick mesh.
