Commonly Asked Questions

Grill Air Supply Dampers - Louvers information

Grill Air Diffuser Screens information

Do Return Air Grills include a filter?

What is the difference between a grille and a register?

If the inside measurement is 10 x 6 inches do I cut my hole 10 x 6 inches?

How to install a grill?

What is the advantage of using resin for grilles?

How long will it take to receive my order?

Are the grilles flat? What is the thickness of the grilles?

Can grilles be flush mounted into the floor?

Are custom grill sizes available?

How are bronze grilles finished?

How do the dampers attach to the grille?

Can your grilles be used as Foundation Air Vents?

Recycle, Reduce, Reuse: Distinguished Design Grills produces grilles using reclycled materials


Grill Air Supply Dampers - Louvers

Air Supply Dampers or Louvers regulate Airflow

All of our standard-sized air supply metal grills include an adjustable damper, for other sizes; contact our Sales team for a quote by phone or email.

Each of our custom grill air supply damper assembly (adjustable louver assembly) includes:

  • A wheel lever for accurate air control
  • A recessed face-plate that allows your new grill to fit tightly against the wall, floor or ceiling
  • A 1/4" decorative face-plate on bronze custom grills connects by 4 screws that allow for easy maintenance.
  • Sturdy inside grille to support heavy foot traffic if installed on floors.
  • Screw holds on vertical height side of grilles is standard. 
  • You can request, "no holes" for floor grilles.


Grill Air Diffuser Screens

All of our standard-sized return grills include a Black perforated Air diffuser Screen. 

For other sizes, contact our Sales team for a quote by phone or email.

The perforated Air Diffuser Screen is designed to diffuse and balance the airflow evenly across the grille while enhancing the look of your installation


Aluminum Return Air Grills include a filter

Filter Return Grills are available in aluminum only. 

We provide a 1" disposable filter and a black foam insert. 

The black foam insert can be washed and re-used when it becomes dirty.


What is the difference between a grille and a register?

A register is a complete unit with a metal louver attached to adjust the amount of airflow. 
If you don't see a register in the size you need, simply combine a louver assembly and a grille to create your own custom register.


If the inside measurement is 10 x 6 inches do I cut my hole 10 x 6 inches?


If the inside measurement on the grille you're looking at is listed as 10" x 6" you can cut your hole 10" x 6" and the lip will fit into your opening.

Please visit our complete set of instructions for How To Measure for the proper sizing of grill orders here.  

  • Always remember the call size of the grill is the same size as the opening in the wall, ceiling or floor.  It is not the outside dimension of a grill.
  • Measure the length of the opening first.  For example: if the opening is on a wall, the length would be the horizontal left to right measurement.  The height would be the vertical top to bottom measurement.
  • Most register manufacturers size their grills in two-inch increments.  Your grill size might be a little smaller or the wall opening size might be a little larger.  This is normal; it creates a loose fit in the wall for the grill.  The loose fit allows room to properly level the grill. 

How to install a grill?

Distinguished Design Grilles can be mounted to any horizontal or vertical surface. 

Grilles can also be provided to match any concave or convex surface.  However, you must provide us with a template stipulating whether you desire concave or convex.

You can order grilles with or without screw holes.  Grills will always be shipped with holes unless you request otherwise.

Grills can be installed with or without a damper. 

We suggest painting the inside of the ductwork directly behind the grill with a flat black paint.  Flat black paint is dark and does not reflect light, thus giving the illusion that the duct has disappeared behind the grill.

Whether you nail, screw or glue the grills to the wall, take the time to make sure that the grills are level.

The light weight of the resin grilles allows for many mounting options. 

  • Screws:  Screws are provided with the grills.  We recommend a #2 Philips tip be used in a cordless drill. The screws provided with the resin grills are self-tapping and color matched to the grill.  Care should be taken to provide secure, properly anchored screws. Make sure wood backing is installed behind the drywall, the screws need to have a secure anchor.  The grills are pre-drilled and counter-sunk for a smooth finished appearance..
  • Pin Nails: Pin Nails create a beautiful finished look, however, the grilles cannot be removed.
  • Silicone: Silicone is a semi-permanent application, the edges of the grille should be latex caulked in order to achieve a clean finished look.
  • Glue/Epoxy: Glue or epoxy is a semi-permanent application, the edges of the grilles should be latex caulked in order to achieve a clean finished look.

What is the advantage of using resin for grills?

What is the advantage of using resin for grills versus using aluminum, steel, wood or plastic for grills, air vents, registers or covers?

As you can see from the chart to the right, our proprietary thermal resin is the ultimate material for producing architectural grilles, return air registers, air vents and other covers.

Metals rust, wood warps and splits and plastic cannot be painted.

Thermal resins that we use today were developed by NASA for use in the space industry.  These resins are a perfect fit for the architectural design industry.  The durability and ability to create an array of designs and sizes in resin sets us apart from what's available on the market today.

We worked for many years to create a formulation that would be:

  • Thermal (both against high and low temperatures)
  • Rigid.  It is obviously critical to have a final grill (air vent cover, register) that is rigid and will not warp.
  • Moldable. We can form the material prior to full canalization to conform to a desired radius.
  • Paintable. Paint adhesion to the grilles is truly important, especially with the temperature variation that grilles, air vents or registers are subjected to.
  • Nail-able. We need to ensure that resin would have similar characteristics to wood when it is pin-nailed or screwed.
  • Dimensionally Stable. It is important that the resin does not expand and does not contract with temperature variations experienced with the system as this can cause warping or the failure of adhesion to the resin surface.
  • Moisture Resistant. Our goal is to allow our customers to use Distinguished Design Grilles for both interior and exterior applications.


(for cured material) Test Method Results
Shore A Hardness ASTM D-2240-86 87-90
Tensile Strength, psi ASTM D-638-84 1300
Elongation, % ASTM D-638-84 160
Tear Strength, pli ASTM D-624-86 300
Appearance   White



VOC (%)

Reaction to Water   None
Flammability   Non-flammable
 The “nail” test.   Simulates wood
 Paint adhesion   Excellent



  contains none
 Impact Resistance   High



How long will it take to receive my order?

Approximate delivery time for resin grills is from a few days to 4 weeks.

Approximate delivery time for metal grills is from a few days to up to 6 weeks.

Depending upon inventory that may be on hand, some popular sized grills will be shipped out the next day. 

Special orders where new patterns are required or where special fabrication is needed to be done may take longer.  When we are backlogged it can take up to 4 weeks for fabrication of your order. 

Grills are shipped UPS ground the next day. Orders are processed as they arrive.

Are the grilles flat? What is the thickness of the grilles?

Yes, our standard resin grills are provided flat; however, Distinguished Design resin grilles can be bent to fit any radius (concave or convex).  Please provide a template to ensure accuracy.


Can grilles be flush mounted into the floor?

We do not recommend resin grills be installed for floor applications.

If floor grills are required we recommend you choose from metal grills made from Bronze, White Bronze or Aluminum available here.

The standard resin grilles supplied by Distinguished Design Grilles are all face mounted (they mount on the surface of the wall or ceiling) and protrude by the thickness of the grills (5/8") into the room.

Distinguished Design Grilles can provide resin grilles for a "flush-mounted" application.  "Flush-Mounted" means that the exterior face of the grille is flush with the wall or ceiling.  Flush mounted grilles are very popular in custom homes as they show a further element of sophistication.

Distinguished Design Grilles designed flush-mounted resin grilles in two pieces:

  • FRAME: The frame is affixed to the wall using screws and then is further secured by the drywall and drywall mud compound that adjoins the outer frame section.  A flange is secured to the back of the frame during manufacture to ensure that the grille and the frame seat together in a seamless fashion.
  • GRILLE: The grille pattern has a slight border around the outside of the same design as the frame.  This ensures that both the grille and frame have a strong air-tight seal.

The cost of the grille and its installation require almost 50% more time, but to all those that have seen or installed the flush-mounted grilles--it is a seamless, beautifully clean look.


Are custom grill sizes available?

Yes.  Custom grill sizes as well as custom grill shapes can be made. We recommend switching to a larger scale of grille pattern when the grille, register or air vent cover gets over a 24" x 24" size.  


How are bronze grilles finished?

How are our bronze grilles finished?  All of our Bronze grilled are finished with top quality patinas from Sculpt Noveau.

How do the dampers attach to the grilles?

Dampers are attached to the grills by two to four (depending upon the total size of the grille, register or air vent) small Phillips screws.

Can your grilles be used as Foundation Air Vents?

Yes, our resin grilles can be used outside on the exterior of a home as a Foundation Vent Cover.  Our grills, registers and air vent covers can also be used for an under cabinet toe kick grill.  Our resin grilles should be primed and painted for home exterior applications.  Resin grills are an excellent choice for the exterior of the home use as they are not affected by the sun or rain or moisture as other grille materials are. Photo


Recycle, Reduce, Reuse: Distinguished Design Grills produces grilles using recycled materials

Mandate of Responsibility: As a manufacturer we are in a position of great responsibility.  We have chosen to take our privilege as a manufacturer very seriously when it comes to "helping the planet." It is important to not just "talk" but to "do"....our actions do speak louder than our words ever can.  From the selection of people, materials and equipment to the designs and internal processes (both manufacturing and office) we will do our very best to reduce our environmental footprint.

Please email us with suggestions or comments relating to environmental stewardship, waste reduction, and material suggestions.

We are currently the only company we know of that is producing a grille using recycled materials.

People:  All members of the Distinguished Design Grille team have been asked as both individuals and as members of our team to reduce, reuse and recycle whenever possible.

Product: Our resin grilles are formed from a thermal resin that contains some recycled filler.  We are constantly developing better formulas that will increase our recycled content while providing the characteristics our clients have come to expect.

Packaging: We have eliminated 90% of our packaging material.  The remaining material is all recycled.  The plastic bags containing the new grilles are made from 100% recycled plastic and printed with vegetable based ink -- 100% earth friendly.

Promotion: A decision to direct people to the web-site for product or company information was made early on.  We introduce ourselves to prospective clients solely through email and web portals.  We have produced a single flyer (printed on both sides) as a basic company and product information sheet.  All other information can be accessed and printed (if necessary) on the website.