Caribbean Disaster Mitigation Project
Implemented by the Organization of American States
Unit of Sustainable Development and Environment
for the USAID Office of Foreign Disaster Assistance and the Caribbean Regional Program


Hurricane Procedures Manual

Link to sections I, II and III

Section IV. Structural Vulnerability and Loss-Reduction Techniques


The section provides guidelines for vulnerability assessments; acceptable criteria and codes for design of structures; performance specifications for procurement; guidelines for contracting, briefing and monitoring of consultants engaged to undertake vulnerability analyses on existing facilities; procedures for the reduction of vulnerability of existing installations including routine and preventative maintenance and retrofitting. The ultimate goal is to reduce the element of surprise by providing buildings and structures with predictable performance at affordable costs.

The review of damage to most buildings from recent hurricanes in the Caribbean showed that roof failure was the primary cause of problems, leading in some cases to complete collapse of the walls. Some roof structures failed as in a hotel in St. Thomas, but generally, the failures can be attributed to the use of light weight roofing material such as 26 gauge galvanised sheeting or aluminum sheeting. Some roofs remained partially intact but the damage to windows, doors and internal partitions was significant. It is recognised that after hurricane damage has occurred there must be a hasty response to the damage by replacing the damaged facilities as quickly as possible, especially in those cases where the hotel has guests. However, it is disturbing to note that reconstruction of many of the hotels which suffered from the recent hurricanes has been based on the same design concepts and the same materials which led to the failures have been used again.

Providing comfortable and safe leisure facilities as well as reducing insurance premiums should be an important objective of hoteliers throughout the Caribbean. Insurance and reinsurance premiums are becoming more expensive and difficult to obtain for facilities which are unable to prove their structural integrity.

There should be a medium or long term plan for upgrading the structure of all hotels to enable the buildings to resist the known hazards.


Hurricanes subject buildings to winds from several different directions, heavy rains, and in some cases storm surge. Buildings must therefore be designed to resist not only high wind speed from all directions, but heavy rain and storm surge.


Wind damage is caused by wrenching and bending forces imposed by gusting winds and the rapid increase in wind force as wind speed increases. With a doubling in wind speed the wind force on the structure increases four times. Wind striking a building produces pressure which pushes against the building on the windward side, and suction which pulls the building on the leeward side. Failure may occur when the external pressure and suction on the wall combine to push and pull the building off its foundation.

If the building is not securely tied to its foundation, and the walls cannot resist the push/pull forces subjected to them, the structure tends to collapse, starting at the roof, with the building leaning in the direction of the wind.

Hurricane winds can also lift the roofs of buildings. In most cases this uplifting effect is the result of the difference in the speed of the wind over the roof. Lower pressures on the leeward side can cause the entire roof to lift up off the walls.


Wind entering the structure through broken or open windows and doors can add to this lifting effect.

The torrential rains that result from hurricanes can intensify flood damage to those facilities affected by storm surge, and can also cause flooding in non-coastal areas. The indirect effects include power outages and the saturation of the interior of buildings with salt and water.

Storm Surge

Storm surge can result in great damage to facilities, even if the hurricane is at some distance away from the coast. The force of winds can push waves toward the shore causing significantly higher water levels at the coastline. The resulting flooding can cause considerable damage, even to properties which are in areas where wind damage is negligible, and severe damage to those properties in areas that are directly hit by hurricane force winds.



After a disaster, avoidable structural damage is a major culprit. Such structural damage is mainly due to inadequate control of quality at all stages of the process - design, detailing, construction and maintenance.

Formal quality assurance procedures should be adopted to ensure that buildings are designed and constructed in accordance with the relevant standards and particularly that proper detailing has been done.

The Regulatory Environment

Building Codes

Checking of compliance with required standards is very important. There is no need to wait for setting up an elaborate inspectorate before mandating building codes. The system of check or review consultants (bureaux de contrôle), routinely used in French territories, is also used with variations in Colombia and in Canada (British Columbia). It has been used on several major projects in the Commonwealth Caribbean, principally at the instigation of catastrophe-insurance providers. Other building codes notably the OECS and Turks and Caicos Codes also mandate the use of a special inspector for the review of plans and construction for important buildings. The review consultant should not be otherwise involved with the project and should report to the owner on all critical stages of the project.

Codes and Standards

The Caribbean Uniform Building Code (CUBiC) contains building standards which if properly used will reduce the vulnerability of structures to natural hazards.

The Code contains Sections on:

The technical standards in the OECS Codes are based on the CUBiC standards, but building regulation in each territory is different. Two OECS countries have approved or passed legislation mandating the use of the Code.

However, it is recommended that the CUBiC standards or other appropriate codes be used by all design professionals in the CHA member countries. The mandatory implementation of a good code with appropriate standards is likely to lead to the reduction in the cost of safe buildings by encouraging more appropriate conceptual designs.

Earthquakes versus Hurricanes

There is a basic difference in the performance expectations of buildings with respect to hurricanes and earthquakes. A building is expected to survive its "design hurricane" with virtually no damage. Even a catastrophic hurricane should only lead to repairable damage. On the other hand, the "design earthquake" is expected to cause (hopefully repairable) damage. A catastrophic earthquake may result in irreparable damage and the building must be demolished. In such an event success is measured by the absence of deaths and serious injuries. The table below compares these issues.


(1) Source of loading External force due to wind pressures Applied movements from ground vibration
(2) Type and duration of loading Wind storm of several hours' duration; loads fluctuate, but predominantly in one direction Transient cyclic loads of at most a few minutes' duration; loads change direction repeatedly
(3) Predictability of loads Usually good, by extrapolation from records or by analysis of site and wind patterns Poor; little statistical certainty of magnitude of vibrations or their effects
(4) Influence of local soil conditions on response. Unimportant Can be very important
(5) Main factors affecting building response External shape and size of building; dynamic properties unimportant except for very slender structures Response governed by building dynamic properties: fundamental period, damping and mass
(6) Normal design basis for maximum credible event Elastic response required Inelastic response permitted, but ductility must be provided; design is for a small fraction of the loads corresponding to elastic response
(7) Design of non-structural elements Loading confined to external cladding Entire building contents shaken and must be designed appropriately

Source: The Arup Journal


There are a number of areas to which careful consideration should be given during the construction of a new hotel. These include:








This is a disappearing feature in an area of the world where it is most needed. Shutters seem to be considered an unattractive feature and is usually overlooked in modern construction. However their construction should not be overlooked as the glass doors and windows offer very little resistance to high winds. Therefore:



  1. Have all parts of buildings (doors roofs, cladding) designed to withstand high wind pressure including suction.
  2. Obtain the necessary Permits for building from the Local Authority.
  3. Have detailed drawings and specifications which cover aspects of construction.
  4. Ensure that persons involved in construction are sufficiently experienced and qualified in hurricane and flood resistance.
  5. Secure all plates to foundations by means of bolts, straps, wood bracing or using special connectors to resist wind or water pressures.
  6. Secure all studs to sill plates and top plates with metal connectors or any other straps that may be available.
  7. Ensure that metal straps or connectors have been used to make a positive connection from the foundation to the structural members of the roof.
  8. Make certain that all materials used and techniques employed provide adequate strength for withstanding potential hazards.


Structural vulnerability audits should be conducted by a qualified engineer in collaboration with a geotechnical engineer. An important task in this assessment is an inspection survey of all the buildings to be audited.

The three main methods of conducting vulnerability audits are :

The Field Evaluation Method uses data obtained from visual inspection and is widely used. It provides an assessment based on past experiences of the buildings with similar geometry, stiffness characteristics, material types, connections and anchorages; it expresses the assessment in general subjective terms such as fair, poor, good, with respect to resistance to extreme winds etc. In the absence of subsoil information, the method also assumes average soil conditions and effects.

This method assigns a rating to the various main characteristics such as symmetry and quantity of resisting elements, anchorage and diaphragm stiffness. The individual ratings are then combined into a composite rating which provides the final assessment.


The failure of the roof exposes the interior of buildings to devastation and often contributes to the weakening and further collapse of the remaining structure.


Emphasis should be placed on the following areas:


Existing structures which do not meet construction standards for foundations should be improved by the following :

Where there are buildings with reinforced concrete block pillars with no projecting steel bars left to help secure the structure to the foundation, the installation of a metal strap fastened to the pillars which in turn is nailed to the bottom plate can offer some measure resistance.










The hotel building must be in a reasonable condition if it is to withstand the forces of the hurricane. Deferred maintenance is counter-productive as the cost of major renovation becomes inevitable. This is much greater than the annual amounts needed for adequate maintenance of the buildings and plant.

Hotel owners should make every effort to bring the condition of the buildings and plant to the standard where a normal maintenance system can cope with the maintenance requirements.

Maintenance plans must be included in disaster mitigation plans. A well-operated system of maintenance for buildings and equipment is also a very effective disaster mitigation measure in terms of cost and facility usage. It ensures the most economic way to keep the building and equipment in the best of form for normal use, given the original design and materials.

If a good system for maintenance is not properly organised, funded, staffed and carried out, then all other disaster mitigation methods could prove insufficient. Experience indicates that roofs, walls, and equipment in general are more vulnerable to failure if normally operated at near breakdown or at any level of technical deficiency. The principal activities to be undertaken for maintaining hurricane resistance (in particular) of the hotel include careful inspection.


Semi-Annual Reviews

Semi-Annual reviews are performed to the ensure the following:

These reviews serve to ensure that an adequate maintenance programme is in place. This in turn ensures a good relationship with the insurance industry and will enable the facility to benefit from more favourable catastrophe-insurance premiums.

Proper maintenance should ensure that the facility can:

All maintenance activities should be systematised and the "anticipate-and- prevent approach" adopted rather than the "react-and-cure approach". Repair is often considered to be the main purpose of the maintenance system, rather than the prevention of the need for repair. The scheduled oiling of door hinges and window operators or the painting of exterior wooden members is necessary to prevent failure of the equipment or rotting of the wooden members.

A comprehensive maintenance system should be instituted by hotel managers, and should comprise:

Planning of Maintenance Activities

Maintenance planning activities are normally carried out and should include the development of a detailed annual maintenance budget. The maintenance staff must therefore be trained to examine all parts of the buildings and plant in their care and to record deficiencies. Such lists must be prepared on an annual basis, but this does not preclude the immediate attention to problems which are endemic in many hotels.

Proposed Maintenance Organisation & Staffing

Reporting of work done is also an essential part of the maintenance system. A simple reporting form is included in this report but the hotel manager may wish to devise his own form which may be more responsive to the problems in the hotel. However, the simpler the form the better will be the chances of having the form properly filled out and submitted monthly.

Checklists and Frequencies for Maintenance Operations

Three tables are presented covering:

The following abbreviations are used in the tables:

Frequency Operator
I: Immediately MS: Maintenance Staff
D: Daily HM: Hotel Manager
W: Weekly AM: Assistant Manager
Q: Quarterly CE: Chief Engineer
A: Annual  

Notes: For frequency the maximum period is given. For operator the person named is the one responsible for seeing that the operation is carried out.

Table 6.1 Building Interior

Spaces Frequency Operator
Washrooms and Toilet
Inspect and report deficiencies
Order replacements
Replace broken elements


Corridors and Guest rooms
Inspect and report deficiencies
Clean walls
Repaint walls

Every 2 years

Ceilings, Interior Roofs, Canopies
Inspect and report deficiencies

Every 2 years

Kitchen and Technical Areas
Inspect all counters, floors and walls
Report and repair


Inspect and report deficiencies
Repair or replace defective pieces


Internal Communication System
Inspect all internal communications to ensure that the system is functioning properly and report defects


Inspect electricity wiring on a room by room basis and report deficiencies.


Repair or replace broken elements



Annual Budget for Maintenance

Hurricane mitigation and planning should be routinely included in budget preparation and planning, as it makes financial sense to build appropriate maintenance, repair and replacement costs into annual budgets.

The maintenance budget should be of the order of 4% of the current value of the facility per annum and should address :-

Maintenance Budget

It is normal for the annual maintenance budget of a hotel with heavy usage to reach 4% of the contemporary capital cost of the building and equipment, assuming that the facilities are in good condition to start with. For hotels, it is estimated that the replacement cost is about US$150,000 per guest room. This figure includes the cost of common and administrative areas but does not include the cost of emergency electricity equipment, water storage or normal furniture and equipment (ff&e).

The maintenance allocation should therefore be no less than US$6,000 per guest room per year plus an allocation of about 8% of ff&e for maintenance of those facilities.

For smaller hotels of less than fifty rooms this allocation of US$ 6,000 per room may be smaller than needed, as the cost of infrastructure maintenance would be proportionately higher than that of a larger hotel.

Proposed Maintenance System

This involves careful review of available data such as drawings, an inspection of the building without invasive testing and a non-mathematical review of existing information on the design and construction of the facility. The consultant engaged to carry out this assessment must be:

The hotel owner should determine the level of risk he/she can accept when discussing building or retrofitting plans with the consultant.

Risk Analyses

Risk is a measure of damage and is a function of the hazard (e.g. hurricane) and the vulnerability of the subject. Risk may be measured in money terms, in percentage-loss terms, in terms of deaths or injured and using many other criteria. The criterion chosen depends on the aim of the analysis. Insurance companies would want to determine the financial loss whereas a public heath agency may be more interested in the numbers of injured and fatalities. The hotel owner may be interested in the cost of the repair and renovation, and on the number of days of lost revenue that will ensue if the hurricane damages the property.

Risk analyses (before the event) assist decision makers in planning rationally for future hazardous events. The hotel owner should determine the level of risk he/she can accept when discussing building or retrofitting plans with the consultant.

Analytical Evaluation

Buildings deemed not wholesome subject to qualitative assessment would require analytical evaluation. Such an evaluation is time-consuming and expensive. It would be best if it were carried out when funds are available to implement a retrofitting program.


Retrofitting for hurricane resistance can be relatively easy and inexpensive especially if the building is adequately maintained. The determination of a retrofitting program follows the qualitative and analytical evaluations referred to above. Roofs are usually prime targets for retrofitting. Light-weight corrugated roof sheeting is particularly vulnerable because of inadequate fastening systems. Better fasteners are now available, such as the Australian cyclone washer and the French-Caribbean fastening systems for trapezoidal-profile sheeting. Overhanging eaves experience very high uplift loads from the wind. These should be reduced.

Hotel owners may wish to have the conventional glazing in large windows and doors replaced with polyvinyl butryal (PVB) laminated glass, which comes in different thicknesses and with different numbers of laminates to suit different conditions. The building owner may also install shutters that have an everyday function of shading as well as protection of windows in times of storms.


The costs of retrofitting depend on the conditions of the subject properties. However, work is now being done on the retrofitting of various facilities and some estimates of costs are available.

An unpublished study now underway on buildings and other infrastructure projects in Jamaica, St. Lucia and St. Thomas showed that for the buildings an additional cost of less than 2 percent of the original construction cost would have prevented the damage by the hurricane, and for the infrastructure projects which suffered much worse than the buildings from the hurricanes, an added expenditure of about 11 percent would have prevented disaster.

Other studies have shown that amounts of from 1 percent to 2.2 percent of increased construction costs were needed for strengthening electricity buildings in Barbados and a hospital in Dominica.

Hotel owners/managers should inform their decisions by these findings.


Hotel staff should provide support for a comprehensive approach to hazard mitigation. The following are guidelines defining the role of the hotel and its staff in planning to mitigate the impacts to hurricanes, and in so doing, maintain the structural integrity of the buildings throughout the facility. Accountability of staff/consultant is necessary for ensuring the soundness of the plant.

The hotel manager has a significant role to play in the construction and maintenance of the hotel. In the first place the hotel owner must:

Construction Records and Plans

All too often the owner cannot find the plans of the hotel. These plans are needed for analysing the structure of he hotel for finding where the buried cables are. The owner must therefore:


The procedures for the procurement of consultants are very often set by the agency financing the project. The procurement procedures will in most cases require that consultants:

Selection Criteria

The selection will also be based on whether the consultant has:

The consultant must also understand, and be able to interpret the terms of reference in a manner which will provide the owner with the result desired.The terms of reference should be clear and concise and the owner's or manager's desired result explained to the consultant.

Selection Procedures

A short list of not more than four consulting firms is required for the selection of a consultant . The short list should be based on knowledge of the consultants who express an interest in the project and who has the ability to carry out the work. The short listed consultants will be required to submit proposals containing:

The owner should assess proposals, negotiate with the selected firm and conclude an agreement. As an alternative to the competitive method outlined the owner may chose to select a consultant based on first-hand knowledge and past relationships. This is often the safest approach.

Briefing of Consultants

The briefing of consultants is an important task which is very often overlooked. The owner must discuss with the consultant specific issues such as:


The following steps should be taken by the management team to ensure that the hotel can respond to the hurricane hazard without major damage:

Link to sections V, VI, VII and appendices

CDMP home page: Project Contacts Page Last Updated: 20 April 2001