Appropriate "retrofit" designs save lives from earthquakes, typhoons, and floods

This download <http://www.unesco-ipred.org/gtfbc/DWf_10_key_points_Hurricane_resistant_construction.pdf> provides a pretty simple enough starting point on what things owners could do to protect life and property.  It appears to have been prepared by Development Workshop France.

The thing is, it's all about design and planning. I like that it starts at #1 with mentioning "site" - site selection is very important and this was very evident in low-income homes we recently reviewed that we found to be very near (< 20 meters) a faultline, or resting on potentially liquefiable soils. 

But if it's there already, for example when you have to deal with protecting homes in New Orleans (USA), then proper design matters even more.  I should mention that design starts with properly identifying and quantifying the hazards.

Another reliable resource for "simple" ways of protecting homes and property from cyclones and floods is the FEMA website. There are some illustrations and plenty of documents there that are all freely downloadable. As a start you can take a look at http://www.fema.gov/plan/prevent/howto/index.shtm#4 for a list of simple "how-to's". You will notice they're pretty much the same as that you sent. When you click on the links, you will be able to download some documents with some illustrations and details. In one case there is some difference in suggestions, like the earlier document ("10 key points of cyclone resistant construction") suggests planting trees while FEMA suggests removing trees.

Whether for earthquakes, cyclones, or flood, it's all about good design of individual homes and property.

But for earthquakes, imagine what if your home is the only one left standing because it has been properly designed. What would other people do after they have lost their homes? Are you ready to answer the knocks on your doors? Will you still have work to go to and a source of income?

For cyclones, as I have mentioned before, even if you have a properly designed home, the roofs of your neighbour's homes that were not properly designed could get blown off and hit your home (the blown-away roof becomes a "wind-borne"/"air-borne"/"flying" "missile"/"debris"), which might not be designed for such because that would mean more costs.

For floods you can design individual homes to be "flood-proof" meaning life goes on for you after the flood (e.g. when your ground floor is elevated, etc), but flood design also involves proper drainage and flood control systems, properly designed dikes and levees, proper site selection, etc.

This all means that, more for floods, but still also for cyclones, and earthquakes, it also has to be a community effort. You would like to have a properly designed/engineered home but you would like to encourage your neighbours and your whole community to do the same. That might be the difficult part because of the costs involved, but in some sense, the good thing about these recent cyclones and floods that affected Bangladesh, the Philippines, Taiwan, even the US (Katrina), and these recent earthquakes in Haiti and Chile is that we're all reminded to prepare for them and design our homes and properties and communities properly, and encourage others to do the same.

A few other things to add to the "10 key points...":
1. Wind speeds tend to be amplified adjacent to sloping terrain (i.e. when you're at the top of a hill, etc). So if possible, avoid those areas, or design to account for the wind speed-up effects. Of course at such locations, flooding is not a concern.

2. I suggest instead of just, e.g. item 5, "Make secure joints...," or items 6 and 7 "Fix the roof..." or "Use diagonal bracing..." it should be "Have a properly designed..." I.e. let an engineer design your home!

Not related to typhoons and floods, but as mentioned - we need to identify and quantify the hazards first.  This may need to be a government effort, but after this work is carried out the next important step is to find a way to appropriately communicate the findings to the affected population.

Then again similar to what happens in our country, some engineers for lack of experience or training, would tend to miss some of these things or think it's not going to be a concern e.g. because earthquakes for example may occur only after so many years, or some think "the design wind speed has been reached already and since it's a 50-year return period wind speed I don't need to worry for the next 50 years".  The latter example is a common misconception.  I wrote about it here.

Some property owners think, "My building has been standing for 30 years now. Why retrofit it?" Obviously because the earthquake hasn't happened yet! I heard that humans in general tend to have this attitude to do something (i.e. retrofitting, etc) only when something has already happened! Or there is an attitude of... "they have installed dikes all around New Orleans, so it must be safe to build a home and an entire community there."

Thus I think a strong educational background is very important - both for engineers, and for property owners.

Unfortunately for individual citizens or even for large companies, money is oftentimes the larger concern. We've heard of clients opting to disregard some of our recommendations because they cost more. Ultimately it's their call. But it's sad that some just accept that when the big earthquake happens here in Manila, we're all "doomed" anyway, so why even bother. Some engineers would tend to do some "magic," to make it look like everything's going to be alright. Clients love those engineers because they mean less expenses! Those engineers are going to sign some certificate declaring that there won't be a problem. Our attitude should be that certificates can't protect us!

The thing is we can't prevent all these natural phenomena from happening but we can minimize or ultimately and hopefully prevent all the damages, economic losses, and loss of lives! Maybe in the near future we're not going to be 100% safe, but certainly we can protect many more lives and property. This starts with education, and with proper acceptance, funding, and execution of designs.

But again, oftentimes money is the bigger issue. Haiti, I think, comparing to Chile, is one good example.

So anyway what I'm saying is before we can start retrofitting our homes and property, maybe we should look to "retrofitting" people's minds... How to do that on a large scale, I'm not an expert of unfortunately.

I've given lectures on wind engineering and senior engineers didn't even show up! We have to remove that "old dogs can't learn new tricks" attitude.  We all have to level-up!

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