How to Recognize a URM

Information gained from the following two steps will commonly tell you if a building is a URM:

  (also see these online publications for photographs and drawings)

 (1) Determine the year the building was constructed.

  • Age of the building is the best clue to start with. In Utah, most URMs were built before about 1980.  Earthquake building codes were widely enacted about 1975, and implemented over the course of a few years, therefore, we use 1980 as an approximate date for the end of URM construction.

    Seis Guide Cover
    We recommend consulting this guide prepared specifically for Utah homes (office and apartment buildings are not discussed). The photos below are examples of common URM houses in Utah discussed in the guide. From Utah Earthquake Preparedness Information Center. A revised version is due out in 2015.
  • But remember, age is only one clue. Many non-URMs were built before 1980, and a few URMs were built after 1980, so follow up with other evidence.
  • While age is the first clue, this does not imply that all older buildings are unsafe and all newer buildings are safe.  Whether by chance or design, some older buildings will stand up quite well to earthquake shaking.  Wood frames, logs, and several other acceptable methods were used long before 1980—many of these buildings are not URMs and will perform quite well.  Some newer buildings still have dangerous flaws. The challenge is determining how a specific building will behave in an earthquake.  Trained builders and structural engineers have the best chance of making this determination.
  • Also, a very small number of older brick or block buildings have been retrofitted. Use caution here, and obtain proof; it would be wise to get an inspection by a trained builder or structural engineer to determine that the retrofit followed modern building codes.

    Seis Guide model A
    Single story double brick URM with basement built in about 1906.
Seis Guide Model B
Single story double brick URM with shelf basement and attic built in late 1890s.

 

(2) Walk around and visually inspect the building of interest.

The following features are common in URMs.  If you see some of these, chances are high that the building is a URM:

  • Brick or cinder blocks on all sides and up to the roof line. But remember—this is just one
    Seis Guide model C
    Two story double brick URM with shelf basement built in about 1900.

    clue.  Many modern buildings that are not URMs, especially apartments and business buildings, also have 100% coverage of brick as a veneer or facing.

  • Sometimes helpful—brick veneers on non-URMs are often only placed on the “visible” side of the building, and often not to the top of the walls.
  • Mortared block or stone foundations (stones may be rough-cut or unshaped).
  • No evidence of wood or steel frames in exterior walls; use caution here, the wood or steel may be “hidden” inside walls—but don’t believe it unless you
    Seis Guide model D
    Two story double brick URM with shelf basement and attic built in about 1900.

    can prove it.

  • King row. Within every four to seven rows of bricks, one row will have been laid sideways for additional strength.  From the exterior, you will see the king row as the “ends” of the bricks, not the sides of the bricks. However, many block URMs do not have a king row.
  • Rafter tie plates.  From the exterior, the end-plates of anchors, ties, or cross braces
    Seis Guide model E
    Single story solid brick URM with full basement built in about 1966.

    may appear as a metal star, rectangle, square, or some other shape near the rafter line.

  • Deeply recessed windows. Window frames are normally set to the inside of the exterior walls, exposing 8 or more inches of wall.
  • Narrow and/or closely spaced windows.

    Seis Guide model F
    Single story concrete and cinder block URM with basement and flat roof built in 1954.
  • Arched or straight lintels over windows.
  • Concrete bond beam cap on top of the exterior wall. Bond beams may also be present over windows and between floors.
  • Lime mortar between the bricks is often crumbly, white or chalky, and porous, and can be removed by a finger or knife.
  • Some older URMs have apparently sloppy workmanship, resulting in bricks that have not been uniformly laid and uneven mortar joints.
  • Consult the publications in our links section for many photographs, diagrams, and detailed descriptions.

 Final notes:

  • The age of construction, combined with these visible clues, will usually give you a good idea if a building is a URM, but will not always be accurate.  Some URMs are easy to recognize; others are difficult. You may need to hire a trained builder or structural engineer to evaluate the building to be sure, especially in some of the following situations:
  • Not all brick, stone, or concrete buildings are URMs. Many modern and a few older buildings are covered by brick or stone veneer or facing, yet have a steel or wood frame that meets modern building codes and have proper anchors to hold brick veneers in place during an earthquake.
  • Some poured-concrete buildings have sufficient steel reinforcement and are not URMs; some do not.
  • Some URMs have been covered with plaster, stucco, panel or sheet siding, or otherwise modified, making it difficult to determine the composition of the supporting walls.
  • Some URMs have higher-quality brick on the front of the building that can make the building appear newer than it really is, or that it has been remodeled. However, the deeply inset windows and/or lintels over the windows are often still visible.  Also, the sides of the building often do not have the better brick.  Use caution in these situations.
  • A few older brick buildings in Utah have been retrofitted to meet modern building codes, but the vast majority have not been retrofitted. Be skeptical if the seller or renter tells you that a building has been retrofitted.  You may want to obtain proof that the retrofitting design and work were done by trained structural engineers and builders.
  • Probably the most difficult category of buildings to evaluate are brick and block homes and businesses built from the 1950s to mid-1970s. Utah has many tens of thousands of URMs in this category (many are the classic red or tan “brick rambler”).  Use all the clues you can, combined with the age, to make a guess.
  • The State of Utah adopted uniform seismic building codes in the mid-1970s.  By about 1980, most building construction in Utah should have followed some level of seismic building code.  However, there is a not a single date after which we can say, “homes and apartments built after this date are safe.”  It took several years to fully implement and enforce earthquake building codes in some areas.  Some later homes built or remodeled by unscrupulous professionals or do-it-yourselfers may have never followed building codes.  In short, we use the phrase, “before about 1980,” recognizing that this is only a general guideline date, and there are many exceptions.
  • Earthquake building codes have been strengthened and improved several times and as a general rule of thumb, the newer the construction the better the building code that should have been followed.
  • Be cautious about the age of a building as listed in real estate literature; you may want to do some additional research in city records and other sources. Some documents may list the age as the date of a major remodel, even if the remodel did not address the URM issue.
  • Large, multi-story, and complexly shaped buildings are sometimes difficult to determine and may require involved study by a professional.

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