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Re: Two conditions in residential construction

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Dennis,

I appreciate greatly your comments and insight. I am sorry if the question
appeared 'loaded'.
Personally, as a building contractor, I have built a great deal under these
provisions; I have been fortunate in that my customers have been content
with the product, despite many limitations.

Steven A.
Los Angeles



Dennis Wish wrote:

> Steven,
>
> You asked me a loaded question. You have described the Conventional
> Construction provisions of the Uniform Building Code and the conditions
> in which homes are allowed to be constructed without conforming to
> full-compliance provisions using either an architect or engineer. As
> long as these guidelines are met and the other provisions of the code
> that need to be tested (geometric irregularity, shear path discontinuity
> etc.) then there is no argument that the builder has the legal right to
> construct the home - even in seismic zone 4 - to these provisions.
>
> But there are issues which the law can not cover. Individual greed or
> misuse of the law is not illegal and the law has not business
> interpreting the intentions of the builder. However, this should not
> allow the public to be taken advantaged of and sold a product without
> disclosing the expected differences in performance separate Prescriptive
> construction from Full-compliance engineering.
>
> Furthermore, a law should not be so full of loopholes as to invite abuse
> that prevents the public from taking measures to protect the largest
> investment they will ever make.
>
> Ignorance:
>
> The building department, building industry associations, architectural
> and engineering organizations do nothing to educate the public as to the
> differences in performance expected of homes built to Prescriptive or
> full-compliance methods. A building permit, in the eyes of the public,
> validates construction and implies that the performance expectation of
> each home is comparable. In truth, we know this is not factual - adding
> mechanical connectors, plywood, straps or evaluating the load path of
> the shear transferred through horizontal and vertical diaphragms will
> result in difference level of performance - more or less damage.
>
> The law does not require the homeowner to be made aware of this fact and
> allows the builder to make advertising claims that stretch the truth and
> fortify the claims of equality.
>
> Workmanship:
>
> The code that requires compliance to prescriptive measures implies that
> the builder (framer or owner-builder) has read and understand the
> provisions. I have yet to meet a framer or General Contractor who has
> read this section of the code or who has the ability to interpret the
> code rhetoric? The legal wording is even more difficult for a layperson.
> Some building departments invest in writing a graphical interpretation
> such as the City of Los Angeles Type V sheet.
> I contend that while the code provides a prescriptive method it does
> little to enforce the ability of the owner or builder to understand the
> provisions. Furthermore, if you design a method of construction
> intending to reduce the degree of protection that is placed in a
> building, the building official should be responsible to take additional
> precautions to ensure that there is adequate compliance during
> construction. I have not seen this occur in my area where the majority
> of homes are constructed by prescriptive standards (check out the
> Structuralist Hall of Shame for examples).
>
> I don't think it is too much to ask that if  you allow a less
> restrictive construction method to replace an engineered solution that
> you require a greater degree of skill by the person assembling the
> system than you would in a more conservative design.
>
> The line of distinction:
>
> The biggest complaint that I have stems from what has historically been
> allowed in building codes. When a professional engineer or architect is
> not used, the provisions are generally more restrictive rather than
> less. If you allow Prescriptive Construction then the baseline for
> compliance should be the same as the minimum level resulting from
> full-compliance to the code. This should be especially true in regions
> of high risk.
>
> Allowances:
> Finally, it comes down to who is building to lesser standards. In my
> opinion, if the owner of the home who intends to live in it rather than
> sell it as an investment should be allowed to determine the level of
> performance with Prescriptive construction offering the least
> protection. Conversely, the Insurance companies should be allowed to
> charge rates that are based on the historic performance of building
> designed to either prescriptive methods or to full-compliance.
> Construction defects should not be excluded from claims because the
> damage has resulting from inadequate workmanship or non-compliance to
> detailing has not occurred at the time the claim was filed. Codes are
> intended to mitigate hazards and this is an anticipation of damage based
> on historic recorded performance of homes with defective workmanship.
> For those who have not heard - Aas vs. William Lyon's was upheld by the
> California Supreme court last December (2000) in favor of the Contractor
> as the courts claimed the defect in workmanship and non-compliance to
> code had not resulted in damage or injury and therefore could not be
> claimed against the developer. This ruling denigrated the intent of the
> code to prevent major structural damage or loss of life. I understand
> that new legislation was in the works to overturn or compensate for this
> ruling, but until it is done, the homeowner is at the greatest liability
> because they must disclose the code deficiencies but have no claim
> against the builder.
>
> Bottom Line,
>
> The solution is to disallow prescriptive methods in high risk zones
> unless chosen by the owner who intends to live in the house for at least
> a long enough period of time as to show that the home was not
> constructed to sell. In this case, the method of construction should
> become part of public record (disclosure) and the Insurance company and
> mortgage lender should be able to set fees (insurance premiums or
> mortgage interest) based on the anticipated level of damage judged from
> historic performance records (such as the Northridge earthquake). Homes
> which are retrofit with mechanical connectors should be rewarded by a
> reduction in premiums.
>
> The minimum level of prescriptive design should be equal to or greater
> than the minimum level of a fully compliance engineered solution.
>
> Structural systems of a residence should not be constructed by an
> inexperienced owner or builder. It should only be intrusted to a framer
> who is certified by education and on-site testing of his or her ability
> to perform the work and to interpret the code.
>
> It is my understanding the NAHB has started Framer Certification
> programs and some of the large builders are participating. My concern is
> that to the best of my knowledge, large developments are not
> prescriptively constructed by designed by Architects or Engineers. The
> Conventional or Prescriptive portion of the code occurs in projects that
> were originally intended to be Owner/builder projects but have been
> allowed for builders or developers of less than 10 homes per year (such
> as exists in areas such as mine where over 90% of the 3000 homes
> constructed in our neighborhood are designed and constructed by
> prescriptive means.
>
> Certification must be required of builders in the private sector who are
> constructing small projects rather than large tracts. This will
> discourage anyone who can swing a hammer from taking the title of Framer
> and being entrusted to construct a load path without the close scrutiny
> of a well trained building inspector (the only source of field
> inspection).
>
> Finally, the method and expected performance level of prescriptively
> built homes must become public record and disclosed to the homebuyer.
> This is the only way for the homebuyer to drive the market and demand
> better quality. Until this happens, the public will remain in the dark
> about the differences in construction quality (unless they log on to the
> Structuralist.Net website).
>
> Since it was a loaded question, it deserved a fully loaded answer. Sorry
> to be so verbose - but most of you expect it of me!
>
> Dennis S. Wish, PE
> California Professional Engineer
> Administrator - The Structuralist.Net
> Website:
> http://www.structuralist.net
>
>
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