Glossary of suspended ceiling terms
How can I identify an existing ceiling tile pattern that I need matched replacements for?
Are suspended ceilings safe to install & use?
How much will a new ceiling cost?
How do I measure an area to determine how much material I will need?
Are there general instructions for installing a suspended ceiling?
What is the minimum clearance I need in order to install a suspended ceiling?
Will the ceiling sag over time?
Can I install an acoustical ceiling in a shower or outdoor area?
How do you clean acoustical ceilings?
Can existing light fixtures be used with a new ceiling?
Can a hanging lamp or ceiling fan be used with a suspended ceiling?
How many fluorescent lighting fixtures will I need for a new ceiling?
Can ceilings be installed over embedded radiant-heat coil ceilings?
Can I put insulation on the back of an acoustical ceiling?
Do I need to install insulation between floors?
Can acoustical ceilings be painted?
Will I lose the sound absorption if I repaint the ceiling?
What is the difference between STC, CSTC and CAC?
What is AC and How do you measure it?
Will ceilings alone provide me with a 1-hour fire rating?
Are hold down clips necessary when following a UL design?
If my ceiling question is not listed here, how can I get an answer?









 

How can I identify an existing ceiling tile pattern that I need matched replacements for?

Several ways are possible. 1: Currently, most of the tile manufacturers are printing ID numbers or product names on the back side of the material. Look there first to see if there is any information. 2: If possible, either bring in a piece of the tile for identification by Delbert Chopp Co. office staff or mail an approximately 6"X6" sample of it to us along with a note to let us know if it is a 2'X2' or 2'X4' tile. 3: Place a piece of the tile face down on a copier and make a copy of the face pattern and FAX that to us along with a note to let us know if it is a 2'X2' or 2'X4' tile.

 

 

Are suspended acoustical ceilings safe to install & use?

Yes.

INSTALLATION. Studies have shown that exposures during conventional installation are below all current occupational standards for nuisance and other listed substances (dust). If power tools are used in the installation, they should be equipped with special dust collection devices, and the workers should wear the appropriate NIOSH-designated respirators.

IN-PLACE. Once installed, Armstrong ceiling products do not represent an identifiable health risk to the general building occupants.

 


How much will a new ceiling cost?

Costs vary according to product design and performance features. The approximate cost for a standard 2X4 square edge tile and standard suspension system in a 10'X10' room would be $100 approximately. Labor costs would vary according to how large or small the project is, any obstructions necessary to work around and other special conditions. Please call 785-827-5484 or e-mail Tom for an estimate.

 

How do I measure an area to determine how much material I will need?  

Measure the width and length of the area and round both measurements up to the next even foot and then multiple the two to arrive at your square footage. Example - you have a 8'5" wide by 12'7" long room. That would be 10X14 = 140 square feet. The reason for rounding up to the next even foot is that tile and grid is only made for 2X2 or 2X4 modules. You must account for the waste material in order to have enough product to complete the area.




Are there general instructions for installing a suspended ceiling?

Please click here for a .PDF basic instruction file from Armstrong. More information can be found here and here. For special conditions, e-mail or call Tom at 785-827-5484

We reference the installation standard ASTM C 636. To obtain a copy call ASTM (610) 832-9500 or get it from the ASTM website.




What is the minimum clearance I need in order to install a suspended ceiling?

Generally speaking, at least 3 1/2" down from the lowest obstruction above the ceiling whether that is the floor or roof joists or plumbing or ductwork. The suspension system T-bars are 1 3/4" tall and you need at least 1 1/2" above that in order to manipulate the tile into the suspension system as well as for clearance for the suspension wires.

You'll also need to take into account what type of light fixtures you are using. 2X2 or 2X4 recessed fluorescent light fixtures may take up to 6" of clearance in order to fit into the suspension system. Recessed can type fixtures can usually be "tucked" into the spaces between joists in order to maximize clearance.

What do I do with plumbing, ductwork, etc, that may be at a lower elevation than where I want my ceiling to be at?

Several options are available. Soffits (boxed in enclosures) can be created with the acoustical ceiling,
sheetrock or wood trim. Examples can be see here, here or here. Please e-mail or call Tom at 785-827-5484 with your project details for a recommendation.




Will the ceiling sag over time?

No, if using a commercial type tile and the ceiling is installed according to its warranty. Armstrong commercial ceilings are treated with a special back coating to resist moisture. When properly installed under the right conditions (no excessive humidity, etc.), they remain level and flat. We recommend using HumiGuard™ Plus panels or fiberglass panels in areas of high or seasonal humidity; they are not recommended for spaces exposed to continuous moisture, such as shower rooms and swimming pool areas. For high humidity or wet areas, you will need to use FRP, vinyl or ceramic based tiles along with an aluminum or stainless steel suspension system. Please e-mail or call Tom at 785-827-5484 with your project details for a recommendation.




Can I install an suspended ceiling in a shower or outdoor area?

Yes, you can. However, you will need an all aluminum suspension system as well as moisture resistant type tiles. If it is a secondary shower that will be used infrequently and will be equipped with an exhaust fan, standard ceiling material may be used with satisfactory results. Please e-mail or call Tom at 785-827-5484 with your project details for a recommendation.




How do you clean acoustical ceilings?


Cleaning Methods:

A - A commercial vacuum system with 100-inches/H2O vacuum capacity is recommended for removing dust particles. The vacuum system cleaning attachment should be a 3" diameter wand with natural hair bristle. A HEPA vacuum filter is recommended to minimize air borne dust during the cleaning process.

B - Using a damp cloth or sponge with a mild detergent, wipe lightly on surface of board to remove dirt.

C - Use a mild household cleaner, like Fantastic, and a soft cloth. Before cleaning the grid, remove the ceiling panels to prevent cleaning solution or dirt from getting on the panels.




Can existing light fixtures be used with a new ceiling?

Yes. But you may have to remove the fixture to install the ceiling and then reinstall it over the new ceiling.




Can a hanging lamp or ceiling fan be used with an suspended acoustical ceiling?

Yes, if supported independently from the ceiling.




How many fluorescent lighting fixtures will I need for a new ceiling?

Standard rule for light fixtures is two 4' fluorescent tubes for every 75 square feet of suspended ceiling.




Can ceilings be installed over embedded radiant-heat coil ceilings?

No. An appreciable loss of heating efficiency will result and the ceiling will not remain stable.




Can I put insulation on the back of an acoustical ceiling?

Only on commercial suspended ceiling panels that are at least 5/8" thick. You must use rolled insulation and install it perpendicular to the cross tees so that the weight of the insulation rests on the suspended grid system, and there is air space between the insulation and the panel. Ask your dealer for specific details.

Note: Insulation must never be placed behind fire-rated ceilings, without prior approval from your building code official. As well, putting insulation on the back of fiberglass panels is not recommended.




Do I need to install insulation between floors?

Most ceilings are installed between floors that are maintained at the same temperature - making insulation unnecessary. Most basements are at least partly heated by heat flow through the ceiling from the heated space above. In that case, attempting to insulate the basement ceiling surface could actually reduce heat flow. Insulation will however, help in noise control in special situations where there may be a sleeping area in a basement directly beneath a busy room above and vice-versa.




Can acoustical ceilings be painted?

Fiberglass, vinyl or FRP panels should not be painted. All other mineral fiber ceiling tiles, panels, planks, and even grid can be painted any color or to mimic any metal - bronze, tin, gold, or copper. Latex or water-based paints are recommended.

1. Install the ceiling material. Tiles and planks may be installed before or after painting.

2. Using a paint roller with a 1/4" nap, apply two coats of paint, waiting 24 hours between coats.

3. To achieve the look of green patina that develops on copper with age, use a small natural sponge to apply a stippling of dark green paint followed 24 hours later by a stippling of light green paint. Vary the placement of the paint and texture of the sponge to create an authentic look.

Note-- For best results on 2' x 2' or 2' x 4' panels: If using a water - based paint, also paint the back side of the panels with one coat of paint and let dry before installing to prevent cupping.




Will I lose the sound absorption if I repaint the ceiling?

When painting acoustical materials, the painter should be very careful that he does not close up the acoustical perforations and fissures . It is through these openings in the surface that sound waves enter the body of the acoustical material and are absorbed. Care should be taken that these perforations are not clogged. At minimum, repainting will result in a .05 to .10 reduction in NRC.

Will repainting void the warranty?

Yes, the tile manufacturer cannot guarantee that the published surface burning characteristics, fire resistance ratings, acoustical performance, dimensional stability/sag, or light reflectance will remain the same after repainting. Field painting will void the warranty.




What is the difference between STC, CSTC and CAC?

STC - Sound Transmission Class - sound reduction from one side of barrier to the other - walls; single pass rating.

CSTC - Ceiling STC - AMA 1-II-1967 Test Method - Two room test, measure of sound that passes through a ceiling across a common plenum and down through ceiling in adjacent (receiving) room; double pass.

CAC - Ceiling STC - ASTM E1414 - ASTM test method introduced in 1995; essentially replaced the AMA 1-II test.




What is AC and How do you measure it?

Articulation Class or AC is a means of rating the relative acoustical performance of products, such as ceilings, used in open plan office environments.

In the open office, the primary source of distracting noise is human speech and a major concern, therefore, is how to prevent intruding speech from distracting coworkers. If there is a general hum or murmur in the space, but no clearly understood words, we can generally "tune this out" as background noise. Speech sounds only become intrusive if the words can be understood. In this type of situation it is difficult not to "listen in" and be distracted (whether you want to listen in or not!).

When evaluating the AC performance, sound is generated by a speaker on one side of a 60" high partition. Data is collected on the attenuation of sound (how much quieter it is) on the other side of the partition at frequencies from 100 to 5000 Hz (very low pitch to very high pitch). The noise reduction data is then used to calculate the AC value of the product being tested. In calculating AC, the sound reduction that occurs at higher frequencies (>1000 Hz) are treated as more important than those that occur at low frequencies. Why? AC allows us to evaluate how well a product will absorb the noise generated by people talking. Voices generate sound at a wide range of frequencies; vowel sounds occur at low frequency and consonant sounds occur at higher frequency. Vowel sounds
only carry loudness. It is the consonant sounds that are most important in speech comprehension. For example, the consonant sounds are the only difference in the words ball, fall, fawn and malt. If a product can absorb most of the consonant sounds, then you cannot tell what the person in the cubicle across the room is saying into their telephone. Again, if you cannot understand the words, the noise is not as distracting.

Ceilings best suited for use in the open office have AC values of 170 or greater. A standard acoustical ceiling (NRC 0.55) will normally have an AC of 150. Non-absorptive materials, such as gypsum board, will have an AC of 120. The highest AC that can be achieved by a ceiling is between 220 and 230.




Will ceilings alone provide me with a 1-hour rating?

No, Fire resistance ratings apply to a floor/ceiling or roof/ceiling assembly in its entirety. Individual
components, such as ceiling panels or suspended grid systems, are not assigned fire resistance ratings. If your architect has not yet determined which UL design should be followed for your specific project, you may have to select a UL Design for code official approval. If so, here is how to select the correct UL fire-rated assembly:

* Establish the hourly rating needed to meet code requirements.
* Determine the existing or planned building elements, including structural, mechanical, electrical and
finish materials, in the fire-rated assembly.
* Refer to the Fire Resistive Rating Summary in the back of the Armstrong ceilings catalog to determine which UL design numbers resemble your building. The summary is divided into categories based on construction type and components.
* Submit the chosen UL design to the code official for approval.




Are hold down clips necessary when following a UL design?

Hold down clips are only required for UL assemblies in which the ceiling panels weigh less than 1.0 lb./square foot. All Armstrong Fire Guard ceilings weigh 1.0 lb./sq.ft. or more and do not require hold down clips.




If my ceiling question is not listed here, how can I get an answer?

Contact Tom Chopp by e-mail or telephone at 785-827-5484.