Best Type Of House Construction To Withstand Hurricanes

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In general terms, the best type of house construction to withstand hurricanes is a concrete frame house since it is defined by a strong and flexible structure built with reinforced concrete. The structure of the building is a key element to withstand hurricanes and reinforced concrete is an excellent choice. However, while exposed to a hurricane, the whole building works as a whole and all the other construction elements defining the house might compromise its strength despite having a great structural resistance.

Below we have ranked the construction methods, that in general, would withstand a hurricane the best.

  1. Concrete frame houses
  2. Modular homes
  3. Light Steel frame construction
  4. Wood frame house
  5. Log Homes
  6. Masonry or Brick and Block
  7. Manufactured or mobile homes

This ranking is based on the general understanding of each type of construction and the common practices around it. For example, a modular home can be designed to withstand 200mph wind speed hurricanes [1] and become the most resistant type of house. However, a modular home without this goal in mind can easily become less resistant than a log home.

Therefore, even if from all construction types a concrete frame house generally offers the best structural resistance, in order to ensure that the house will safely withstand hurricanes, it won’t be enough to only define its type of structure.

Important features of a Hurricane resistant type of house

Having established that the structure of a concrete frame type of house offers the required qualities to withstand strong winds, it is necessary to define those aspects of the house that have a strong effect on the building’s hurricane resistance but are not determined by its typology definition.

A hurricane resistant type of house needs to consider:

  • Type of foundations
  • Facade or sidings
  • Openings: windows and doors
  • Roofing finishes
  • Building Shape

A house exposed to these extreme storms needs to offer protection against very high wind speeds as well as to all the other dangerous hazards involved in a hurricane such as the impact of flying debris, heavy rainfall and flooding.

Type of foundations

Flooding is a common consequence of hurricanes and to ensure both the integrity of the building and the safety of its occupants, a hurricane resistant house will ideally be elevated from the ground. The most optimal solution is to raise the house from its foundation with piles, as shown in the next image.

These set of columns are built with reinforced concrete, just like the house structure itself since due to its flexibility, it has the capability to withstand the horizontal forces that water flooding might create [6].

These kind of foundations are not necessarily required for every hurricane resistant house unless they are placed in coastal areas or in flood prone areas. To identify if a house is built in such a location, FEMA provides an online service to locate flood prone areas [7].

Facade or sidings

One of the most dangerous and damaging hazards for buildings during hurricanes is the impact of flying debris. If the overall exterior of the house is not robust enough to receive the impact of heavy and accelerated debris, the consequences can be catastrophic.

The best siding material to resist the impact of flying debris is reinforced concrete [8], though in this case concrete would have an even better performance if reinforced with hybrid fibers instead of steel, since the Fiber Reinforced Concrete (FRC) panel is the material that has shown the least damage when impacted by high velocity debris [9].

Since hurricanes are accompanied by heavy rainfalls, a hurricane resistant house needs to ensure that the overall exterior of the house avoids water and moisture infiltration. Which will be achieved by installing an uninterrupted water resistive barrier covering the whole house, including roof, walls and floor [10].

Openings: windows and doors

One aspect of the overall exterior that should never be forgotten is the protection of all  the openings (windows and doors). While a window is easily replaceable, a broken window during a Hurricane can lead to a catastrophic outcome because if the wind is granted access inside the house, the pressure indoors will change dramatically adding forces and pressure for which the house is not designed for and causing significant damages such as the blowing off of the roof [11].  

While hurricane shutters are quite popular, the most optimal way to protect the openings is by installing impact resisting windows, since they have a much better outcome when being hit by flying debris compared to shutters [12].

Roofing finishes

The roof is a key aspect of a hurricane resistant house that needs to be built very carefully taking into consideration its design, the materials used in the top layer and its anchorage. A thoughtful roof design is key to reduce damage and avoid the most dramatic consequence of roof damage which is having the entire roof blown off.

A roof blown off is caused by the uplifting pressures of the wind, so it is important to minimize the exposed areas where winds could exert an uplifting force. Some of these areas are the eaves of the roof which should be reduced to be of a maximum length of 20 inches (or 50 cm) [13].

In order to ensure the integrity of the roof,the top layer is of extreme importance. The forces of the wind can easily peel shingles and other roofing materials if they are not securely attached. In a hurricane resistant house, the top layer of the roof is highly secured.

In this case what matters the most is not the material itself but the placement of it. For example, Asphalt shingles can easily be teared apart when the shingle fasteners are improperly located [14]. The pictures below show clearly the consequences of an incorrect roofing execution.

But not only the top layer of the roof needs to be properly anchored, but it is imperative for the entire structure of the roof to be properly anchored to the walls as well. Usually reinforced concrete structures have a better outcome with the anchorage of the roof and those structures that need special attention in this area are wood frame houses, since an inadequate nailing or bracing can cause dramatic failures [15].

Shape

The shape of both the roof and the building have a strong impact on how well the building will perform during a hurricane. Aerodynamic shapes will help reduce the wind pressure by deflecting the air flow [16]. Houses encompassing aerodynamic shapes are usually symmetric, compact and rounded buildings [17].

 

The structure of a concrete frame type of construction is an excellent choice for a hurricane resistant house

The structure is the skeleton of the house, the element in charge of holding the house up. The strong wind pressures common during hurricanes put a lot of stress over the structure and a structural failure can easily result in the building collapse and compromise the safety of its occupants.

By analysing all the standardized types of constructions, from wood frame to prefabricated houses, we can state that a concrete frame construction would be the most likely to resist hurricanes in most of the cases. Since its structure is built of reinforced concrete, a material characterized by the addition of steel bars in concrete.

This combination ensures a material that merges the strength of concrete together with the flexibility of steel. As a result, we obtain a strong and flexible structure or frame equipped to sustain wind forces of 150 kg/m2 [2]. Actually, the efficiency of reinforced concrete in front of hurricanes is so noticeable that the Federal Emergency Management Agency (FEMA) recommends its usage to build hurricane safe rooms [3].

Flexibility is a very important feature for a house subject to strong winds, because even if as a general rule the structure of a building needs to be able to withstand vertical forces (the weight of the building, furniture, usage, snow…); wind forces impact the building in a horizontal direction.

The quality of being flexible avoids serious structural damage due to strong winds [4] because flexible structures will absorb the wind-induced forces by bending or compressing without cracking [5], while allowing the structure to return to its original position undamaged once the wind forces are gone.

However, even if the structure of a concrete frame type of house offers the ideal characteristics to withstand the violent winds associated to hurricanes, the structure is only one part of the house and a resistant structure can’t ensure the integrity of the entire building.

Therefore, even if compared to other generalized types of constructions the concrete frame type offers a better chance to withstand hurricanes. We need some more information about the building to know if in its entirety, it is capable of resisting not only the strong winds, but all the other dangers related to a hurricane such as the impact of flying debris, heavy rainfall and flooding.

Even concrete frame houses need hurricane resistant design

Thanks to its flexible and strong structure, a concrete frame house is the best type of construction to withstand hurricanes. However, not every concrete frame house is hurricane resistant unless every aspect of its construction works together to ensure the house as a whole is hurricane resistant.

A hurricane resistant concrete frame house is built of robust façades and impact resistant windows and doors to avoid the damages caused by the impact of flying debris. It is also elevated from the ground and waterproofed to protect the house from the strong rainfalls and flooding.

When designing a building a hurricane resistant concrete frame house, all details from design to execution, need to be considered to ensure a good performance in front of such extreme weather event. Moreover, an aerodynamic design can be of good help as long as the construction of the house is well executed.

References

  1. Adams, K. (2017, October 25) Florida’s leading sustainable home builders launch two new models Green Dwellings https://www.greendwellings.net/2017/10/25/green-dwellings-makes-hurricane-resistant-homes-breeze/
  2. Concrete Frame Structures  Understand Building Construction http://www.understandconstruction.com/concrete-frame-structures.html
  3. (2021, April) Save Rooms for Tornadoes and Hurricanes Federal Emergency Management Agency, FEMA P-361, Fourth Edition https://www.fema.gov/sites/default/files/documents/fema_safe-rooms-for-tornadoes-and-hurricanes_p-361.pdf 
  4. Zhang, W. and Gruber P. (2019, August 23) Wind-resilient civil structures: What can we learn from nature NRC Research Press https://cdnsciencepub.com/doi/pdf/10.1139/cjb-2019-0034
  5. Flexible Materials  The Gund Company https://thegundcompany.com/materials/flexible-materials
  6. How flooding affects concrete Knight’s Companies https://www.knightscompanies.com/blog/concrete/how-flooding-affects-concrete/ 
  7. FEMA Flood Map Service Center: Search by address Federal Emergency Management Agency (FEMA) https://msc.fema.gov/portal/search
  8. (2005, June 1) Which is the better building material? Concrete or steel? Buildings https://www.buildings.com/articles/36029/which-better-building-material-concrete-or-steel
  9. Han, D., Park, YJ., Han,MC. And Yi, ST. (2019, February 21) Evaluation on Protection Performance and On-Site Applicability of Hybrid Fiber-Reinforced Concrete International Journal of Concrete Structures and Materials 13, Article number 19 https://ijcsm.springeropen.com/articles/10.1186/s40069-018-0329-5
  10. (2019, September 9) 3 Essential Features of a Hurricane Resistant Home Barricade Building Products https://barricadebp.com/news/3-essential-features-of-a-hurricane-resistant-home 
  11. Barrineau, T. (2018, 6 August) In a Hurricane, protecting doors and windows is crucial Glass.com the Industry’s Home Address https://info.glass.com/protect-doors-windows-hurricane/
  12. Impact Windows vs Hurricane Shutters: What is Better? Engineered Glass Systems (EGS) https://egsinternationalllc.com/impact-windows-vs-hurricane-shutters-what-is-better/
  13. Is there such a thing as a Hurricane Proof Roof? Keller roofing & Inspections https://www.roofing-keller.com/blog/is-there-such-a-thing-as-a-hurricane-proof-roof/
  14. (2019, June) Best Practices for Minimizing Wind and Water Infiltration Damage Federal Emergency Management Agency (FEMA) https://www.fema.gov/sites/default/files/2020-07/minimizing-wind-water-damage_hurricane-michael_florida.pdf
  15. Suaris, W. and Khan, M. S. (1995, 1 February) Residential Construction Failures Caused by Hurricane Andrew Journal of Performance of Construction Facilities Vol. 9, Issue 1
  16. Beautiful Architectural Concepts Designed to Resist Hurricane Force Winds Architecture Art Designs https://www.architectureartdesigns.com/beautiful-architectural-concepts-designed-resist-hurricane-force-winds/  
  17. (2005 March) Summary Report on Building Performance, 2004 Hurricane Season Federal Emergency Management Agency, FEMA 490 https://www.fema.gov/sites/default/files/2020-08/fema490.pdf

Fig. 1 Olick, D. (2019, May 31) Here’s how to build a hurricane resistant house – not as expensive as you may think CNBC https://www.cnbc.com/2019/05/21/how-to-build-a-hurricane-resistant-house.html

Fig. 2 & 3. (  2019, June) Best Practices for Minimizing Wind and Water Infiltration Damage Federal Emergency Management Agency (FEMA) https://www.fema.gov/sites/default/files/2020-07/minimizing-wind-water-damage_hurricane-michael_florida.pdf