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What properties of decorative sheet vinyl flooring are important to consider when selecting pet resistant resilient flooring? Resisting surface abrasion and scratching, especially from large dogs, is a tall order for any flooring material, not just resilient flooring. Learn how to use the product standard to understand sheet vinyl flooring materials.

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Last business day before Christmas, I received two email messages about a project that will be issued for construction the first week of January. The architect's office always closes for Christmas week. So I called to find out if replies were needed, immediately. No, they could wait until the new year, I was told.

A Sore Point
The conversation revealed what was not in the email. An on-going confrontation was continuing between a purchasing agent and the architect. The agent was expecting written confirmation of fire code requirements that applied to the finishes and furnishings the agent was to provide.

By talking and listening (rather than emailing), I understood this issue was the source of much stress. An immediate solution would be best.

The Stress Source

The agent listed fire testing requirements that she believed to be commonly required for hotel guest rooms. However, the listed requirements were not entirely correct. Carpet was expected to be ASTM E84, Class A. This test is meant for wall finishes, not for floor finishes. Carpet cushion was expected to meet ASTM E648 and ASTM E662. Neither test is cited by the code. The code requires the cushion and carpet to be tested by NFPA 253. And the list goes on for several more similar items.

The Relief
I spent about an hour. I read the purchasing agent's comments; researched the California Building Code; and responded to the email. I provided details, including the applicable code citations, for each response. I recommended a solution for each condition. Some affected the construction specs. Some affected the interior design specs. Each solution was simple.

The Result
Near the end of my day, I received this reply from the architect.

"Quite impressive. It's a privilege to work with someone of such great knowledge. You make our business so much easier. I learn a lot from you.
I will pass this back to all parties.
Thank you again and have a great holiday weekend." - Rafael Velazquez, WATG

What a great way to end the day, the week, and begin the holiday season. I was glad I could help. And the recognition? It makes me want to help again, the right attitude to bring to the New Year.

While staying at a resort hotel, last week, I saw an interesting behavior in response to an interesting design solution. The entry level elevator lobby had two elevators, two hall call stations, and two elevator position indicators. The two call stations were less than four feet apart.

Guest Behavior
Photo Nov 20, 9 11 27 AM.jpgA hotel guest approached the elevators and without hesitation pressed the UP button on both call stations. I thought it odd that the guest felt the need to press both buttons. So I stood and watched as other guests tried to use the elevators. I saw the same behavior repeated several times. Each time, the second elevator arrived at an empty lobby (except for me). No passengers boarded. Soon afterward, both elevators were called to another floor. The position indicators gave this away.

Curious, I began exploring. The elevator lobby was arranged identically on all floors, two cars, two call stations, and two position indicators. (7th floor lobby shown in photo) I thought perhaps one car may have been a service car. No, both cabs were identical, fitted out as passenger cars.

Simplex Controls
The controls for both cars were a simplex type - meaning each call station calls only one car. When the call buttons on both stations were pressed, both elevators responded. Only one car collected any passengers.

Operating both cars to respond to a passenger call on the same floor is a complete waste of energy. One car chases the other, only to find no passengers. Then the process is repeated. It would be interesting to check the elevator control records, especially if the cars included a weight sensor to see how may "empty" trips were made in a day, a week, or a year. Then calculate the energy that was totally wasted and the unnecessary wear and tear on the machine. The annual operating costs are likely double what they should be.

Select the Right Controls
Use simplex controls for a single car. Use duplex controls (single call station) for two adjacent cars. Use group controls (one or more call stations tied together) for more than two cars in a single bank of elevators. Duplex and group controls will dispatch a single car to each hall call. The controls analyze each car's position and direction of travel to select the most efficient response to each call.

Elevators consume a lot of energy. Today's electronic controls are designed to minimize the expended energy while minimizing the passenger wait time.

Providing simplex controls on adjacent elevators keeps the power companies and elevator service companies happy. Owners, however, deserve a better design solution to help minimize operating costs.

Airport Rain Barrel.jpgWill this get a LEED innovation in design credit for putting rain collection on public display? I didn't find any indoor plants needing irrigation. So, I am sure that is not the intent. Within the last month, I saw two examples in very public locations showing lacking maintenance: the Airport in Philadelphia, Pennsylvania and the Jacob Javitz Convention Center in New York City.

Fortunately, I guess, the airport had only one location in the terminal I visited. But it was certainly obvious - right next to the gate sign (top right). Javitz Draped Space Frame.jpgThe airport example is one that is impossible to miss.

The convention center seemed to have 25% of the roof area draped with plastic to catch the leaks. The convention center example was far less obvious. You had to look up between the bright halide lamps to find the black plastic hung below each bent of the space frame structure with the black roof deck above (second right). The drainage tubes are draped in festoons to the closest column where they are bundled and descend (third right) to collection barrels (bottom right).

Architects:

The most common construction failure loss is from leaking roofs. Avoid the liability. Choose roofing systems for long term durability, not initial cost. Understand that the roof will never have the Javitz Drainage Tubing.jpgmaintenance the manufacturer recommends to ensure maximum service life. Consider protected membrane roof systems to eliminate UV degradation and minimize thermal stress - two prominent factors in roof failures.

Owners:

Take care of your roofs. Inspect them annually. Make necessary repairs before leaks occur. Diverting the leaks to keep your occupants dry does not solve the problem. Leaks continue to deteriorate the insulation, metal deck, and structure until the leak is repaired. Wet insulation is useless as a thermal barrier. Allowing the leak to continue requires additional, unnecessary energy to heat and cool the facility and complicates the ultimate repair.

Thought for the Day:
Javitz Rain Barrel.jpg
"Another flaw in the human character is that everybody wants to build and nobody want to do maintenance."
- Kurt Vonnegut

From this example he must be right.

Through personal experience I have recently discovered a facet to interior design for accessibility that is widespread, yet nearly unacknowledged. As an industry we tend to think of accessible issues as "Wheelchair" issues or "Impairment of the senses" issues. I believe as an industry we could be looking a little deeper into who will utilize a space to optimize the functionality of the design.

 

In the last several weeks I have experienced a medical condition new to me. Due to years in construction, several unfortunate incidents with ill-tempered, four-legged transportation, and numerous falls I find myself with what is commonly known as a, "Bad lower back". Triggered by improper form while lifting something heavy, the deterioration of vertebrae and discs has resulted in compression of the sciatic nerve on my left side. This condition causes muscle cramping and nerve pain down that leg - a sensation not unlike receiving a root canal starting at the lower back and extending to the left ankle, performed by a chimpanzee wielding an electric drill equipped with a 3/8 inch, carbide-tipped masonry bit. Standing is possible only for a limited time. Sitting in a standard chair is out of the question. The pain is immediate and severe, and only way to relieve that pain is to lie flat and allow the compression to ease. The relief can be  instantaneous.

 

In the process of researching and seeking a cure I have learned that more than 90 percent of Americans will experience this condition in their lifetimes, and many will experience it more than once. Over 90 percent! So this is not just me whining, but rather, a very common malady.

 

Virtually everywhere I go (including hospital and physician's waiting rooms and the spinal center I visited) one must lie down on the well travelled floor to survive the "waiting". Lovely chairs and couches are prevalent in waiting rooms, lobbies, airport gates and lounges, etc. There are planters, gardens, even children's furniture, but no extended horizontal seating. In my own conversations with medical personnel they note that many people employ some type of contortion on the "standard" furniture to manage their pain while waiting, yet the waiting rooms are equipped with standard chairs, coffee tables, etc. Herein lies our challenge in interior design.

 

How about a flat bench folks? How about a long, well made flat seating surface around six feet long, and maybe even a little wider than standard chair depth? It could have cushions, but please, no armrests. Most people would choose the cushy chairs, but for those 90 percenters who have a need to relieve a little excruciating pain, the flat bench is a lifesaver. These benches could be incorporated into the most clever and artistic of interior designs, would serve as perfectly fine seating for the general public, and would greatly reduce the moaning and sobbing sounds we all find so disturbing in lobbies and waiting rooms. Compared to chairs and couches, flat benches are relatively inexpensive, yet can still be stylish.

 

Since this is such a common and serious condition, perhaps some signage over the benches would be in order...something showing a reclining person with sparks or flames coming from their back, and with a caption such as, "Please yield to those in pain". The odds dictate that most interior designers would one day benefit from this small yet compassionate design detail.

 

This personal discovery has caused me to wonder how many other very common conditions could be addressed with very simple solutions. The best design will address the most acute of the user's needs. It should be a continual, industry-wide challenge to reach that depth of design.

I had to respond to an architect about a contractor's submittal for architectural woodwork. The contractor submitted MDF panels as the basis to construct the plastic laminate finished woodwork. The architect contended that MDF panels are not plywood. Yet by definition they are. The panel cores must be specified to ensure the selection is not left to the fabricator.

Architectural Woodwork Standards (AWS) is the North American standard for woodwork. The standard is published jointly by Architectural Woodwork Institute (AWI), Architectural Woodwork Manufacturers Association of Canada (AWMAC), and Woodwork Institute (WI). If you do not have a copy of the Standard, join AWI to receive your copy.

AWS has two sections that bear on this discussion. Section 10 includes the standards for casework and Section 4 includes standard for sheet products. Section 10 references Section 4, without modification, for the sheet products used to construct casework.

Section 4 defines plywood as "a panel composed of a crossbanded assembly of layers or plies of veneer, or veneers, in combination with a lumber core, composite core (MDF or particleboard) or combination core, that are joined with an adhesive."

Panels used for woodwork governed by AWS must be a minimum of 3 plies - two face plies and a core - a plywood panel. AWS does not set a default core. Section 10 allows the manufacturer to select the panel core for casework. If a particular core is required, it must be specified. Simply specifying plywood is not sufficient if specific performance is required.

The illustrations shows a 7-ply veneer core plywood panel and a 3-ply MDF core plywood panel. Plywood panels must always contain an odd-number of plies to be a balanced construction so the panel remains stable.

Veneer plywood.jpgMDF plywood.jpg










AWS includes a table rating relative properties and performance as Excellent, Good, and Fair for eleven available cores. The ratings can help designers and specifiers select the correct material for each project. MR designates "Moisture Resistant" and FR designates "Fire Retardant."

Readily Available Cores

Limited Availability Cores

Particleboard
MDF
Hardwood Veneer
Softwood Veneer
Hardboard - Standard

Combination
Lumber
Hardboard - Tempered
MR Particleboard
MR MDF
FR Particleboard


In addition to availability, the table includes six properties to consider:

Flatness
Visual Edge
Surface Uniformity

Dimensional Stability
Screw Holding
Bending Strength


The properties for each core are rated as Excellent, Good, and Fair. The following cores received Fair ratings (worst performance) for the properties listed. Be careful selecting these cores when Good or Excellent performance is expected.

Panel Core Type

Property - Rated Fair

Particleboard
Hardboard - Standard
MR Particleboard
MR MDF
FR Particleboard

Screw Holding

Hardwood Veneer
Softwood Veneer

Flatness

Softwood Veneer

Surface Uniformity

FR Particleboard

Visual Edge


So select the panel construction carefully to match the project needs. Consider the use, abuse, and loading that the panels must resist.  And make your selection accordingly.

Be Careful! A word of caution for anyone using the 11th Edition of Architectural Graphic Standards: The coefficients of linear thermal expansion for selected materials given table A.87 on page 1035 are unitless. Without units attached to these coefficients, the values are useless. There is no clue if the values given are English, metric, or something else. Units make a difference.

The coefficient of thermal expansion (α) is a constant for each material and is used to calculate the total movement of a given length of material over a given temperature range.

English Measurement
α = Material Constant (inches/inch/degree F, or 1/degree F)
L = Length (inches)
ΔT = Temperature Change (degree F)

Metric Measurement
α = Material Constant (m/m/degree C, or 1/degree C)
L = Length (m)
ΔT = Temperature Change (degree C)

Then to calculate the thermal expansion ΔL, the formula is:

ΔL = α x L x ΔT

The result of the formula will be a value, measured in inches or meters.

As a comparison, I checked both the 5th and the 6th edition of Architectural Graphic Standards for the same information. Unfortunately, both editions included units for the coefficient, but the units were identified incorrectly as inches/degree F. Here is what I found:

 

Material

Coefficient of Thermal Expansion (α)

11th Edition (unitless)

6th Edition (inches/degree F)

Aluminum

24 x 10^-6

12.8 x 10^-6

Brass and Bronze

19 x 10^-6

10.1 x 10^-6

Copper

17 x 10^-6

9.8 x 10^-6

Glass, ordinary

9 x 10^-6

4.7 x 10^-6

Concrete

12 x 10^-6

6.5 x 10^-6

Lead

29 x 10^-6

15.9 x 10^-6

Steel

11 x 10^-6

6.7 x 10^-6

 

Upon searching additional on-line sources, I discovered the coefficients for linear thermal expansion shown in the 11th edition are metric values. But there is nothing in the published table that provides this information.

Without the units, calculations of thermal expansion may provide values that are double or half the real value.  So be careful you are working with the right units.

With fond memory of my college structures professor, Willis W. (Big Daddy) Wertz, "Units, they must be right, or you are wrong."
All I could think was "Were you born in a barn?" It was one of the memorable lines from my father when anyone left a door open, spilling all the precious conditioned air to the exterior.

When returning to the car after a meeting in Philadelphia, PA, there was no mistaking that blast of arctic air. The ambient air temperature was in the high 90s during an early June heat wave. But what was the source? I turned and headed into the wind.

Thumbnail image for IMG00110-20110531-1742.jpgThere it was, the accessible entrance with low energy automatic operators. One door leaf was standing half open. From 20 feet away, it was not just noticeably cool, it was a stiff breeze (easily 10 mph or 900 fpm) of chilled air. I was surprised there was no crowd taking advantage of the respite from the heat.

I couldn't help myself.  I had to investigate.

Even with my help, the door was difficult to close. It is no wonder the closer could not pull the door shut. There were two obstacles: the positive pressure from the lobby HVAC system and zero clearance at the door sweep. The 3 x 9 foot door provided a magnificent sail to catch the HVAC breeze. The door dragged on the threshold which compounded the resistance the closer was required to overcome.

With the door standing half open, the vent area was over 21 sf. At the estimated 900 fpm, that is 19,000 cf of conditioned air lost to the exterior every minute. Hmm...60 minutes per hour, 9 hours a day, five days a week, 52 weeks a year.  Where you born in a barn?  Fix it!


Top and bottom surface bolts are used on the inactive leaf of pairs of doors. The bolts hold the door closed until the full door opening is require. For office suite entry doors shown in the photo, the need is usually during move-in to get furniture through the door. But the full opening may be required for equipment replacement, maintenance, and other routine purposes.

IMG00112-20110610-0905.jpgWhen specifying surface bolts or any hardware device, keep in mind the height of the installation for each door opening. This door is 3 x 9 feet. The top bolt is less than 12 inches long and requires a key to unlock the bolt. The only way for most people to operate the top bolt is to stand on a ladder.

The door is inconvenient, although not impossible, to use. Just store the ladder in the lobby coat closet for those times the full opening is needed.

An alternative solution will improve the user operations and safety. Use an automatic top bolt with a manual bottom bolt. This arrangement provides top and bottom latching when the active leaf is closed. And it keeps employees and maintenance staff safely on the floor. The inactive leaf can be opened without a ladder, simply by retracting the manual bottom bolt.
TCNA Cover.jpgThe publication of 2011 versions of the TCNA Handbook and ANSI A108, A118, and A136 addressed the challenges in large format tile installations. This Tech Tips will explore changes in the new TCNA Handbook and make a comparison to our 2009 Tech Tips on the same subject. Be sure to talk with product representatives to stay current with industry trends.

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