Truncated Domes

It’s three in the morning and the snow is rapidly accumulating on our city streets, and I'm thinking of detectable warning systems truncated domes.   The kids are dreaming of a snow day, tree branches resemble icicles, and our city snow plow’s awake to show their stuff.  As the snow melts away, the streets and sidewalks display their new scars.  These wounds range from chipped up curbs to missing and/or destroyed truncated domes required under our Americans with Disabilities Act (ADA). Let’s review the detectable warning systems truncated domes and their ADA requirements.

Individual truncated domes are measured at the base, top and in height. 

• The dome base diameter is to be between .9” and 1.4”.
• Dome tops are to have a minimum of 50% and maximum of 65% of the base diameter
• Height requirements for each dome are exact at .2”.
• Dome spacing is measured in two ways, center to center and base to base.
• Two adjacent domes measured from center to center must be a minimum of 1.6” and maximum of 2.4” apart.
• Base to base the spacing must be .65”. 

There are numerous products offering truncated domes for your ADA requirements.  The materials of the detectable warning systems range from polymer composites (www.armor-tile.com) to stainless steel offerings (www.advantagetactile.com).  While the composite product is very durable, numerous municipalities and engineers are turning to the Advantage stainless steel brand. 
Advantage stainless steel products are growing in favor for environments that have snowplows, vehicular traffic and heavy industrial use.  These are some of the numerous benefits to this product.

• 16 gauge stainless steel. 
• Duragrip coating for maximum toughness and durability.
• Integral slip resistance technology.
• Reinforcement for the tile is every 3”, with a, “C” shaped flange for maximum locking and vehicular support. 
• 10 year warranty. 

truncated domes

Cleanup crews can go around after the snow and pickup the debris, garbage, etc, but replacing affixed materials is extremely costly in dollars and time.  Detectable warning systems' truncated domes for curb ramps and sidewalks are ADA requirements that no one wants to repair or replace.  The two main features that must be considered and emphasized with regards to truncated domes are durability and lifecycle cost.  When it comes to the Advantage tactile product I refer back to an old saying, “measure twice, and cut once.”      

By Shawn Osborne