Definitions for Ceilings & Ceiling Types - Fire & Health Codes
A ceilings is an overhead interior surface that bounds the upper limit of a room. It is generally not a structural element, but a finished surface concealing the underside of the floor or roof structure above.
A cathedral ceiling is any tall ceiling area similar to those in a church.
A dropped ceiling is one in which the finished surface is constructed anywhere from a few inches to several feet below the structure above it. This may be done for aesthetic purposes, such as achieving a desirable ceiling height; or practical purposes such as providing a space for HVAC or piping. An inverse of this would be a raised floor.
A concave or barrel shaped ceiling is curved or rounded, usually for visual or acoustical value, while a coffered ceiling is divided into a grid of recessed square or octagonal panels, also called a lacunar ceiling.
Ceilings have frequently been decorated with fresco painting, mosaic tiles and other surface treatments. While hard to execute (at least in situ) a decorated ceiling has the advantage that it is largely protected from damage by fingers and dust. In the past, however, this was more than compensated for by the damage from smoke from candles or a fireplace. Many historic buildings have celebrated ceilings, perhaps the most famous is the Sistine Chapel ceiling by Michelangelo.
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The ceiling is an often-overlooked surface in the cleaning environment
primarily because of the perception that ceilings are too
difficult or impossible to clean.
Some building managers feel that simply painting the
ceiling is faster and easier than any cleaning process.
A basic understanding of ceiling surfaces is critical
for deciding the best technique for restoring the
"clean" look to the surface. Most ceilings fall into
one of several categories.
Acoustical (acoustic) Ceiling
- This
ceiling type is the most common found in commercial buildings
and in most office areas. It is porous and basically appears smooth with small pinholes
and crevices. The
primary function of all acoustical tile is for sound control.
There are, however, many types of acoustical tile, each
with unique functions.
Glacier
- This
ceiling is constructed of acoustical ceiling material.
However, it
looks
much like icicles. Glacier ceilings must be sprayed with
ceiling cleaning solution from four different directions to
assure complete coverage of the surface.
Popcorn
- This ceiling is sprayed onto a previously existing
non-acoustical type ceiling already in existence.
The result is a stucco-like surface.
The disadvantage of this system is that if a stain
occurs, there is no tile to replace it.
Burlap
- Burlap is very similar to acoustical ceilings.
However, it has a greater tendency to absorb dirt
directly into the fiber making it difficult to clean the tiles
with one cleaning.
Vinyl-wrapped
sheetrock
- This is normal sheetrock or wallboard painted with enamel,
latex or flat paint. The
enamel and latex paints allow the spray/wipe technique to be
used. Flat paint
ceilings should be repainted when they become soiled since the
flat paint can be removed with mild agitation or detergents.
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PVC (Plastic, Vinyl) Ceiling Tiles
Ceiling tiles waterproof, mold, mildew and bacteria resistant, impact damage resistant, fire rated for kitchens, easy to install and maintain only requires soap and water to clean
out lasts all other tiles.
Corn Based Ceiling Tiles
Ceiling tile prototypes made entirely of corn based, bio-degradable plastic.
Keratin Based Ceiling Tiles
Plastic made from Keratin, a substance derived from chicken feathers.
Ethanol Based Ceiling Tiles
Using ethanol as a feed stock for vinyl is not a new concept, though until recently the economics have not been practical.
Thermal Ceiling Tiles
Thermal Ceiling Tiles basically are tiles with a thermal barrier for protection from above the ceiling a 15 minute proof is usually standard.
Drop or Suspended Ceiling (Tiles)
A ceiling suspended (dropped) grid system by hangers (wires) with standard ceiling tiles (Armstrong, USG, Celotex, Ceilume, PVC) of 2' by 2' or 2 by 4' to cosmetically cover a/c ducts, wiring, etc as well insulating from up ceiling for fire protection, reduction in a/c bills, etc.
Cleaning or Painting Acoustic or Porous Ceiling (Tiles)
Acoustic or Porous Tiles are traditionally made of wood or mineral fuber and are no more than a paper product, hard to clean, water spots can only be removed by painting which can cause you to lose your fire rating and have issues with the fire marshall and your insruance company. Health Department issues will be with the mold that grows in Acoustic tiles. Customer issues will range from a nasty looking ceiling or one sagging to those who will be bothered by the mold in your ceiling.
Cleaning or Painting Non Acoustic or Non Porous Ceiling (Tiles)
Other than PVC, Ceramic, or Steel all other tiles may be cleanable for a while until their vinyl coating either peels off or wears. Painting may cause issues with Health Department and Fire Marshall check with manufacture, health department and fire marshall before doing so .
Myths
Acoustical levels (NRC) for acoustical tiles remain the same, not true for most what makes them acoustical are the holes in them, once they start filling with dirt and dust the NCR levels drop.
Tiles treated to handle humidity will last a long time, at best 10 years and that is if you are not in an extreme humid area or do not have major leaks. These tiles can cost as much as 4 times normal tilels. You are better off with PVC, Ceramic or Steel tiles.
Tiles treated to handle Mold and Bacteris will last a long time, warranties on most are good as long as the tiles do not get wet, moist or damp meaning as long as they are dry. You are better off with PVC, Ceramic or Steel tiles.
Hour rated tiles will give protection in a fire, FALSE, most were tested with a metal grid assembly and after 1-3 hours the test showed the grid still there so gave the tiles an hour rating even though they were gone much, much sooner. The best protection for barrier is either Steel or Concrete and a sprinkler system installed correctly no less than 1 head per 100 sq ft .
PVC off gasses, somne does, the new car smeell is PVC, Shower Curtains are PVC, Most PVC Ceiling Tiles such as Genesis have absolutely no odor to them.
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Drop
or suspended ceilings were developed to hide ac vents, pipes, wires,
etc and make the ceiling more attractive. Then noise issues arose and
the acoustical tile was suppose to be the answer. The big problem
with a lot of acoustical tiles is they have holes and the holes is
what helps with the noise but the holes fill up with dust and dirt in
a short time. And as they do the noise level rises and the people
adjust each day since it is a somewhat slow process.
The
big move now is for drop ceilings to cut back on energy use by
keeping warm/cool air below the drop ceiling.
The
myth here is that insulated tiles will help with this, the truth is
there is a 1" gap around every tile called the ceiling grid that
the tile sits on that is not insulated. So purchasing insulated tiles
and installing them is like blowing insulation in 80% of your attic
and leaving 20% without. The only true way to insulate your ceiling
is to roll it on or blow it in. Rolls may work better for access to
ac ducts, pipes, etc as long as those working above remember to put
the roll back when finished.
The
space above the dropped ceiling is often used as a plenum
air return for ventilation systems, requiring only enclosed ducts
that deliver fresh air into the room below. Return air enters the
ceiling space through open grilles across the ceiling.
Fire and Smoke Code:
ASTM
International (ASTM),
originally known as the American
Society for Testing and Materials,
is an international standards
organization
that develops and publishes voluntary consensus technical standards
for a wide range of materials, products, systems, and services. The
organization's headquarters is in West
Conshohocken, Pennsylvania,
about 5 miles northwest of Philadelphia.
ASTM
predates other standards organizations such as BSI
(1901), DIN
(1917) and AFNOR
(1926), but differs from these in that it is not a national
standards body,
that role being taken in the USA
by ANSI.
However, ASTM has a dominant role among standards developers in the
USA, and claims to be the world's largest developer of standards.
Using a consensus
process, ASTM supports thousands of volunteer technical committees,
which draw their members from around the world and collectively
develop and maintain more than 12,000 standards.
ASTM E 84 (NFPA 255) test
for flame Spread and Smoke Index,
Hourly
ratings for most ceiling tiles is a myth. If you do not purchase the
entire assembly used in the test then the tiles have no rating (A
non-combustible gypsum core ensures fire
safety with 1-1/2- and 2-hour fire
rating
achievable depending on the fire-rated
assembly.) The process was to put a wood or mineral fiber tile in a
metal grid and test. If any of the assembly is left after an hour
then it is 1 hour rated, after 2 hours then it is 2 hour rated,, and
so on. The problem is the tiles are gone in a matter of minutes so
the fire can reach the next floor. The best protection is a concrete
building with sprinkler system, A sprinkler system installed
correctly with at least one working sprinkler head per 100 sq ft min
will give much more protection that a fire rated ceiling assembly.
Standard
Classification System for Ceiling Tiles based NFPA 222/ASTM E 84:
Class
Flame
Spread Index
Smoke
Development Index
1 or A 0-25 0 - 450
maximum
2 or B 26-75 0 - 450
maximum
3 or C 76-200 0 - 450
maximum
Anything above 200 (for
flame spread) is unrated
Code
officials and regulatory agencies frequently use the Flame Spread
Index and Smoke Developed Index values obtained by the NFPA 255/ASTM
E-84 test in the acceptance of interior finish materials for various
applications
NCT
Genesis Tiles 2x4 are 20.1 for flame and 199.9 for smoke at the high
end. Low end our 2 x 2 are 15.7 for flame and 97.8 for smoke, All of
our tiles are well within the Class A or 1 rating.
Most
public buildings no matter for profit or not require a class A
ceiling tile and at the least a class C..
Other
Health Issues:
Other
issues with tiles from the past has been asbestos, lead, and now with
acoustic tiles is mold, mildew, bacteria they harbor and allow to
grow.
As
long as tiles are made of wood or mineral fiber (which is 90%) the
mold and bacteria issues will continue to grow.
Many
hospitals are harboring bacteria in their ceilings from previous
patients passing them on to new patients.
Many
schools, businesses and any where there are drop ceilings are adding
to the mold problem, alergies, etc with mineral and wood fiber tiles.
Although
acoustic design and patient privacy is important, we believe the
prevention of Sick Building Syndrome (SBS) is a vital component of
overall patient health. Poor indoor air quality, toxic mold, mildew
and allergens negatively impact the safety, health and well-being of
patients and employees.
While
antimicrobial treatments, such as BioBlock® or Microban®,
applied to standard, water-repellant ceiling panels can help to
prevent sick building syndrome, most
of the warrantees of these ceiling panels becomes void if exposed to
any water, condensation or humidity. Yet exposure to these conditions
is almost universal in healthcare facilities.
Yes,
you can find some really cheap tiles but remember you get what you
pay for. How many times will you change them before you realize you
are spending more in the long run.
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