RAFTER - slopping beam supporting a roof
RAIL - single horizontal structural support used to connect balusters or spindles (top rail, bottom rail, side rail) i.e. See HANDRAIL
RAILING - a series of rails used as structural support used in various applications including staircases and balconies. See BALUSTRADE, SPINDLES
RAILROADED - to turn fabric where selvages run horizontally rather than vertically, often used when fabrics are non-directional to avoid unwanted seams
RAMP - sloped surface or walkway connecting two levels, often designed for handicap accessibility
RANCH HOUSE - a dwelling for a rancher and his family, typically one level with attached garage. See ABODE, APARTMENT, BUNGALOW, COTTAGE, DOMICILE, DWELLING, FARMHOUSE, HOME, HOUSE, LOFT, MANOR, MANSION, STUDIO, VILLA
RAYON - the first synthetic fiber filament made from various cellulose solutions. See VISCOSE
RATIO - relation of one object to another, often used when calculating drapery quantities or paint mixtures, i.e. 3:1 ratio, 3 parts to 1 part = 4 parts
RECESSED LIGHT - lighting fixture installed within a ceiling
RECTILINEAR - straight lined
RECYCLED - any portion of an object salvaged used again for a similar or different purpose
RECYCLING TEXTILES - textiles reused or restored to reduce waste
REEDING - carved wood detail combining a series of thin, parallel, convex lines used as inlay or applied carving
REFLECTED CEILING PLAN - scaled drawing of a space indicating all ceiling fixtures and height transitions. See ELECTRICAL PLAN, ELEVATION, FLOOR PLAN, FURNITURE LAYOUT, PLAN VIEW
REFLECTOR - any surface used to amplify or deflect light or sound
REFRIGERATOR - metal cabinet or room specifically designed to keep food cold
RELIEF - raised ornamentation
REMODELING - reconstruct, to alter, change, modify
REP or REPP WEAVE - plain weave fabric created when large filling yarns run through fine warp threads producing horizontal ribs running selvage to selvage
REPEAT - vertical and horizontal numerical measurements relating to the pattern of woven or printed fabric, distance from a point in a pattern to the same point where it occurs again
REPOUSSÉ - decorative metalwork outlined and embossed, hammered or punched on the back side
REPRODUCE - to copy, imitate or duplicate an original object, style or structure
REPRODUCTION - a copy, imitation or duplication of an original object, style or structure
RESIDENCE - a place to reside; dwelling. See ABODE, APARTMENT, BUNGALOW, COTTAGE, DOMICILE, FARMHOUSE, HOME, HOUSE, LOFT, MANOR, MANSION, RANCH HOUSE, STUDIO, VILLA
RESILIENCE - ability of carpet fibers to spring back to original shape after being crushed
RE-SALE CERTIFICATE - form establishing proof of tax liability of user
RETRO - term used to describe styles and fashions from the past, most frequently to describe items from c. 1940 to c. 1960
RETURN - distance from the front of a window treatment to the wall
REVERSE PRINTING - dye-resistant products are applied, which results in only the background of a fabric being dyed
RIBBON - thin band of fabric with finished edges used to tie, trim or embellish
RID - Registered Interior Designer
RINGS - round carved, cast or hand-wrought hardware strung on a pole or rod to suspend fabric panels. See CLIP RINGS
RISER - vertical member of a staircase supporting the horizontal tread
ROCAILLE - shell-covered rock work ornamentation, French origin
ROD - wall or ceiling mounted horizontal support, commonly used to support drapery treatments, i.e. wooden pole, iron rod
ROD POCKET - stitched pocket to hold drapery rod
ROLLER SHADE - flat window treatment, typically made of fabric or vinyl, using spring rollers inside the frame of window for raising and lowering
ROLLER PRINTING - fabric manufacturing process using engraved metal cylinders for each color
ROMAN SHADE - window treatment utilizing a series of fabric tapes, rings and cords stitched onto the backside for raising and lowering, which draws up into horizontal pleats when raised 
--- Flat Roman - when fully extended the shade is perfectly flat
--- Soft Fold Roman or Hobbled - when fully extended the shade retains soft folds down the full length of the shade
--- Shirred Balloon - unstructured poufs of fabric shirred at the top
--- Inverted Pleat Balloon - structured poufs where the heading is flat with uniformly spaced reversed pleats
--- Austrian Shade - vertical rows of fabric gathered in swags
ROOF - exterior shingles, metal, clay tile or other water-proof materials covering the structural canopy of a building
ROSETTE - round, elaborately detailed pattern resembling a rose, most often found in a carved wood or plaster mold application
ROTARY-SCREEN PRINTING - fabric manufacturing process where dyes are extruded from a series of perforated tubes to create a pattern, while the fabric runs underneath the machine
RTA - Ready-To-Assemble furniture
RUG - soft floor covering laid onto a floor but not permanently attached
RUN - woven or printed goods produced on a single machine at one time with the same overall appearance