Here is a quick parts list for 1 panel, followed by a longer explanation of some items. Please read these descriptions as they contain important safety information and information on locating materials.



Major Parts:

4" x 3/4" Board - 14 feet, cut as follows: 2 - 4' long boards, 2 - 22 1/2" boards, 4 - 6" long corner brackets (see picture below)

3/4" x 1" moulding - about 8 feet, cut into two 46 1/2" lengths

2 inch thick rigid fiberglass (Owens Corning 703 or similar) - One 2' x 4' sheet

Acoustically transparent fabric - about 2 yards @ 38" wide



Hardware/Fasteners:

Wood Glue

16 - Drywall Screws

4 - 4" x 1/4" carriage bolts

8 - 1/4" nuts

3-5 feet - Picture hanging wire (at least 30 lb. capacity)

2 - Heavy duty frame tabs

1 or 2 - Picture Hooks (at least 30 lb. capacity)

2" strip of clear tape

50 - Upholstery staples

16 - Brads

4 - Light duty felt furniture glides



Tools:

Table saw

Drill with 1/8" bit and phillips head driver

Phillips head screwdriver

Staple gun

Scissors

Wire cutters

Utility knife

Tape measure

2 Bar Clamps





Details



Lumber - We decided to build the panels to 2' x 4' outside dimension because it was cheaper to trim a bit off the fiberglass than to purchase and waste all the extra lumber that we would have needed to cut the slightly longer frame pieces. For our frames, we decided to use MDF because it is inexpensive and fairly strong. We used 2 4' x 8' sheets for all 12 frames. First we ripped a sheet and a half into 4" wide boards (18 boards), and then we cut the remaining board into 1" strips for our moulding. You could use an alternative such as pine, but it's more expensive, and its not going to show in this design anyway.



Fiberglass - Rigid fiberglass looks just like the roll of fluffy stuff you stick on your walls, but it is compressed and is considerably more dense. It is not available at most general home stores or construction supply houses, but if there is an insulation supplier in your area, they usually have it in stock or can order it rather quickly. It is also sold as "fiber board" and "mineral fiber." It is not necessary to use Owens Corning branded material, but check with the manufacturer to ensure a density of about 3 pounds per cubic foot.



It is available unfaced or with a backing called FRK (foil reenforced kraftpaper) which looks similar to the material used to package pre-made garlic bread. While this option does help increase the panels effectiveness in the low frequency range, it is considerably more expensive (about 33% where we bought ours) and also increases high frequency reflections, so for general use, it's better to get the unfaced material. For our project, we made 8 unfaced panels and 4 faced panels, placing them in strategic locations (basically closer to the corners) to help with specific problems in our room. If you are more familiar with room acoustics, a combination of panels might be a better option.



When working with fiberglass, please be sure to wear a dust mask, eye protection, gloves, and long sleeves to prevent injury and irritation from the material.



Fabric - IMPORTANT: Spend the extra money to buy flame retardant fabric or purchase a fireproofing spray for fabrics and use it on your panels! If the fabric is not flame retardant a warm light, and open flame from a candle, etc. could cause a major fire as you will have flammable materials hanging on your walls! This is not only dangerous, but against the fire code in most areas.



Although you can buy acoustically transparent fabric made for this purpose, it tends to be rather expensive and provides no real benefit in this application. Muslin, burlap and other such materials are great choices. Just find something that will allow air to pass through it freely. If you can hold it up to your mouth and blow through it easily, it will do fine for this project. Just DON'T FORGET TO MAKE IT FLAME RETARDANT.



We used $ .99/yard muslin and treated it with a flameproof spray. It's not very durable, so you may want something a little better if you're planning on moving the panels or tend to find your walls getting bumped and dented a lot. The Cadillac of fabrics for this type of panel is a product made by Gilford's of Maine. It's expensive, but it is fire rated, durable, and comes in a nice selection of colors.



Picture hanging materials - Although picture wire, hooks, and eyelet tabs are readily available at hardware stores and big box home stores, the markup on these items is very large and the quality tends to be sub par. We recommend going to a local picture framing shop and asking to purchase these items out of the framer's inventory. A framing shop may also be willing to help you select the right products and even make sure that you're using them properly. We paid about ten dollars for all of the materials needed to hang 12 panels. Equivalent materials from a national retailer would have cost us over 60 dollars!



Due to the weight of these frames, we recommend overestimating their weight requirements. We used 50 pound wire and hooks, even though they should have worked fine with the 30 pound versions.