Salt air, strong sun, and hurricane seasons put Upper Keys homes to the test. If you are eyeing a canal or waterfront property around Islamorada, Key Largo, or Tavernier, the way a home is built affects safety, upkeep, and insurance costs for years to come. This guide breaks down CBS versus frame construction, plus poured concrete, pilings, impact glass, and metal roofs, so you can buy with confidence. Let’s dive in.
What CBS and frame mean in the Keys
CBS stands for concrete block system. These homes use concrete masonry units with reinforcing steel and grout, often finished with stucco. When engineered and maintained, CBS offers strong wind resistance and a long service life in our coastal climate.
Wood frame homes use traditional stick framing and are usually elevated. Frame can perform well when connections, fasteners, and enclosure details meet coastal standards, but it demands more vigilant maintenance in heat, humidity, and salt air.
CBS at a glance
- Strong wind performance when fully grouted and reinforced.
- Durable exterior when stucco and sealants are maintained.
- Watch for signs of chloride exposure like rust stains or spalling.
Frame at a glance
- Requires robust hurricane straps and a continuous load path.
- Higher maintenance for paint, sealants, and pest control.
- Elevated designs help reduce flood risk when properly engineered.
Poured concrete and hybrid systems
Poured, or cast in place, reinforced concrete creates monolithic walls and slabs. Fewer joints can mean better long term resistance to wind, water, and salt intrusion when the mix, rebar cover, and finishes are designed for marine exposure. Many buyers also encounter insulated concrete forms, which combine a reinforced concrete core with built in insulation. Both can deliver excellent structural performance when detailed for coastal conditions.
What to look for:
- Engineering records and permits that confirm structural design.
- Evidence of coastal grade materials and corrosion protection.
- Maintenance history for any crack repair or surface sealing.
Why elevation and pilings matter on the water
On canal and oceanfront lots, elevation is central to both safety and insurance. Many sites fall into AE or VE coastal flood zones. VE zones have stricter rules. Elevated homes on pilings allow water and waves to pass underneath, reducing loads on living areas during surge.
Key points for buyers:
- Elevation Certificates drive flood insurance pricing. Higher finished floors relative to base flood elevation can lower premiums.
- In V zones, open foundations or breakaway walls are common requirements.
- Pile materials vary. Timber needs regular inspection, while concrete or steel piles need corrosion protection and connection checks.
Openings and roofs that stand up to storms
Impact glass vs shutters
Impact rated windows and doors provide always on protection without deployment. They can improve comfort and may qualify for wind mitigation credits if properly documented. In salt environments, you still need to maintain frames, hardware, and sealants.
Shutters, from roll down to accordion or panels, can also protect openings. They can be cost effective but require storage, regular service, and timely deployment before storms.
What to verify:
- Recognized product approvals for windows, doors, or shutters.
- Condition of frames, tracks, motors, and weather seals.
- Installation permits and receipts for insurer recognition.
Metal roofs vs asphalt shingles
A coastal grade metal roof, installed to high wind standards, often delivers long service life and can reduce wind premiums when documented. Choose corrosion resistant materials and stainless fasteners, and plan for periodic inspections of coatings and flashings.
Asphalt shingles can work in the Keys, but they generally have shorter lifespans and are more prone to wind uplift. If you are considering a shingle roof, look for high wind ratings and recent installation records.
Coastal maintenance you should expect
The Upper Keys environment accelerates wear. A realistic maintenance plan protects your investment and supports insurance eligibility.
- Exterior walls: inspect stucco and caulking, repair cracks, and refresh coatings every 7 to 15 years based on exposure.
- Concrete and masonry: watch for rust staining or spalling, address promptly, and manage drainage to reduce saturation.
- Roof: check fasteners, flashings, and coatings, and touch up any scratches on metal to prevent corrosion.
- Openings: clean tracks, replace worn weatherstripping, and reseal perimeter joints as needed.
- Fasteners and hardware: use stainless or hot dip galvanized components rated for marine exposure.
- Ventilation and moisture: keep assemblies dry, manage humidity, and monitor for condensation or mold.
Insurance basics for Keys buyers
Wind and flood are separate policies in Florida. Homeowner policies often include a hurricane deductible that is a percentage of the dwelling value. Flood insurance pricing depends on your flood zone, elevation relative to base flood elevation, and foundation type. Elevation certificates and mitigation features like flood openings or breakaway walls matter, especially in coastal V zones.
Wind mitigation credits may apply for documented features such as roof to wall connections, roof deck attachment, secondary water resistance, hip roof geometry, and impact protection for openings. Ask for a wind mitigation inspection report if one exists.
Due diligence checklist before you bid
Gather documents early so you understand maintenance, safety, and insurability.
- Elevation Certificate and the current flood zone.
- Structural drawings and permits for foundations, shear walls, and connections.
- Product approvals for impact windows, doors, or shutters.
- Roof records, including material, installation date, fastener type, and coating history.
- Pile type and marine protection details where applicable.
- Maintenance records for stucco, waterproofing, and any concrete repairs.
- Photos and inspection notes for corrosion, spalling, rot, mold, or pests.
- Locations of HVAC, water heaters, and electrical panels relative to flood levels.
- Existing policy declarations for wind and flood, plus quotes for your scenario.
CBS vs frame, which is better here
There is no single winner. A well built CBS or poured concrete home, with reinforced connections, protected openings, and a maintained exterior, can perform very well in the Keys. An elevated wood frame home can also be a strong choice if it has modern hurricane connections, impact protection, and a disciplined maintenance record.
Focus on the entire system: foundation and elevation, wall construction, roof type and attachment, opening protection, corrosion control, and the location of utilities above expected flood levels. Quality of design and documentation often matters more than the label on the wall system.
Quick buyer playbook
Top three priorities on canals and waterfront
- Elevation and flood implications. Obtain the Elevation Certificate and get flood quotes early.
- Openings and roof connections. Confirm impact rated protection and documented roof attachments for potential wind credits.
- Corrosion control and maintenance. Look for coastal grade materials and a clear upkeep history.
Assemble the right inspection team
- Home inspector experienced with Florida coastal homes.
- Structural engineer for foundations, shear walls, and connections.
- Roofing specialist for metal or high wind shingle systems.
- Marine or piling specialist for waterfront structures.
Your next step
If you are weighing CBS versus frame, or deciding whether a metal roof or impact glass is worth it for your Keys lifestyle, a focused plan can save you time and money. Bring the right documents, choose the right inspections, and compare insurance scenarios before you commit. When you are ready, connect with Islamorada Life Realty for local insight and a calm, concierge process that fits how you want to live on the water.
FAQs
What is CBS construction in the Upper Keys
- CBS uses reinforced concrete block with grouted cells and rebar, finished in stucco, and is known for strong wind performance when engineered and maintained for coastal exposure.
How does elevation affect flood insurance in the Keys
- Elevating living space above base flood elevation, and adding freeboard where possible, can significantly reduce flood premiums. Your Elevation Certificate is the key document.
Are impact windows better than shutters in Islamorada
- Impact windows provide permanent protection and can earn wind mitigation credits, while shutters can be cost effective but require deployment and ongoing maintenance.
Will a metal roof resist salt air on canal homes
- Yes, when specified for marine environments with corrosion resistant materials, stainless fasteners, and proper coatings, and when inspected and maintained on a schedule.
Can older wood frame homes be insurable in the Keys
- Often yes, but retrofits like modern roof connections, impact protection, and elevating utilities may be needed. Costs and insurer requirements vary.
What documents should I request before making an offer
- Ask for the Elevation Certificate, structural permits and drawings, product approvals for openings, roof documentation, maintenance records, and any wind mitigation report.
