What is NRC?
What is CAC?What is AC and how do you measure it?
What is the difference between STC, CSTC and CAC

Cleaning Instructions

How do you clean Armstrong ceilings?

Clean Room

How do the ISO/TC209 clean room class ratings compare to the Federal Standard 209E clean room class ratings?
What do the clean room class ratings mean?
What products do we recommend for clean room applications?
For a clean room application, do I need to seal my panels into the grid?

Field Painting

Can acoustical ceilings be repainted? How?
Will I lose the sound absorption if I repaint the ceiling?
Will repainting void the warranty?
How do I match my ceiling for touch-up?

Fire Performance

What is flame spread and smoke developed, how does this relate to fireguard and Class A?
Will ceilings alone provide me with a "one-hour" rating?
Which Armstrong ceilings and grid can I use if a fire-rated assembly is required?
Are hold down clips necessary when following a UL design?
How do types BF, P and PC in UL designs relate to actual products?
How do I obtain an hourly rating for a corridor?
How can I get a copy of the UL fire resistance directory?


What is the minimum clearance for installing an exposed T-bar grid system?
Are there general instructions for installing a suspended ceiling system?
Can ceiling panels be installed using glue?
How do I cut and treat tegular edges for mineral fiber and fiberglass panels?

Product Selection

How do I know which Armstrong ceiling product meets the ASTM E1264 type, form and pattern classifications?
Which Armstrong ceiling products can be glue-applied?



Which ceiling products can be used for seismic applications?
What do I need to know to be able to install ceilings to meet seismic requirements?
Is there a step-by-step installation procedure for seismic requirements?