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After viewing the recent storm damage, can I get the local weather perspectives- more storms on the pacific or Carrib side? Are these heavy annual rain events (with this amt of damage) common? I somehow thought that because CR was so close to the equator that storms wouldn’t have enough time to develop much punch or is it more rain than wind.
Also there was a 5.2 Earthquake 20 miles off the southern pacific coast, i guess the Pacific side, being part of the entire “ring of fire” would be more prone, are buildings built with earthquakes in mind? ThanksI am told that the Seismic Code here is more stringent than California so new construction would be considered reasonably safe.
Scott Oliver – Founder
WeLoveCostaRica.comThe conventional wisdom here is that, if you build to the earthquake code, your house may roll downhill into the river but the walls won’t crack.
Traditional masonry structures here are built like bomb shelters. There is rebar, structural columns, etc in a well built structure that are unlike anything you’ve seen in the U.S. That helps to explain why, in a time of rising steel and concrete prices, building costs are going up.
As an architect and contractor in the US, structural steel frame buildings are the most earthquake resistant because the structural system has a much greater ability for movement. For example, the top of the Columbia Center in Seattle (76 stories) is designed to sway as much as 9′ for both wind and seismic. For houses, wood framing is more earthquake resistant than masonry or concrete. Your drywall may crack, but the structure will remain intact. Masonry is the least earthquake resistant of all.
California, Alaska and Hawaii are Zone 4 seismic areas, the most stringent. Oregon and Washington are Zone 3. Kansas would be a Zone 1.Interesting, it’s a goofy hobby, but I watch the USGS site everyday and I bet few realize how active the Pacific rim regions are. So, if looking at homes to buy in CR would I be able to look at construction and the materials to gauge its earthquake worthiness, in your opinion?
Most modern structures built to current codes will withstand a 7.0 or less. Anything over a 7.0 is a “severe” earthquake. Anything over 8.0 is a “great” quake with massive destruction. To answer your question tracymartin, it is difficult to determine structural quality in CR unless you witness the actual construction. The predominant building materials are concrete, CMU block and stucco. Stucco hides what is underneath. CMU and concrete are completely dependent on the amount of reinforcing steel and steel at the connections from floor to walls, beams, columns etc. These connections canot b seen in the finished product. In my experience, the reinforcing steel used in a typical CR home is undersized (#3 rebar or 3/8″ dia.) which is not allowed in the US for other than ties for larger rebar or sidewalks. The density (closeness of each rebar piece) is also typically inadequate. Wood framing that is anchor bolted into a concrete foundation will withstand a quake better that concrete or masonry. Another issue with concrete is that is often hand mixed so that each batch has different strength properties and they tend to use to much water to make it easier to work with. Too much water severely weakens concrete. If you live in a larger city that actually has pre-mix batch plants, the quality control is significantly higher.
grb…
You make some very interseting points as far as construction strength in CR. What size rebar would you recommend as being adequate for a single storey house on the Pacific side of CR.
I currently live in Canada and most all residential construction is done with wood framing ( 2×6 on 16″ centres for exterior walls). Could this be sufficient for an earthquake prone zone such as western CR. Foundations here are concrete and at least 4′ underground (more if a basement is included) Rebar is not used, but could easily be incorporated into the foundation.
For CR homebuilder or anyone else with specific knowledge,… would this construction method be allowed in CR (wood frame on reinforced concrete foundation). Would it be feasible from a cost perspective… (availability of wood framing materials)
Any help would be greatly appreciated…
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