Do It Yourself (or DIY) information includes answers to the following questions:

How Do I Measure Door Size or Frame the Correct Rough Opening?

The first step in measuring the height and width of your new door is to measure the rough opening where the door will be placed. Rough opening means the opening of the stud wall structure prior to installing the door frame (door jamb). The process for determining the door height and width needed for your rough opening is as follows:

For Interior Doors

  1. Measure the height of the rough opening, from the floor to the bottom of the upper stud of the opening (see the illustration below for this measurement). Measure the height on both corner edges of the opening, and then use the smallest of these two measurements. Then, subtract 3” from this height. This equals your needed door height.

Example:  Rough opening height = 83”. Door height needed = 80”, or 6’/8” (83” – 3” = 80”, or 6’/8”)

  1. Measure the width of the rough opening, from inside of wall stud to inside of wall stud (see the illustration below for this measurement). Measure this in three places—top of the opening, middle of the opening, and bottom of the opening, and then use the smallest of these three measurements. Then, subtract 2” from this width. This equals your needed door width.

Example:  Rough opening measurement = 32”. Door width needed = 30”, or 2’/6” (32” – 2” = 30”, or 2’/6”)

If you are framing the rough opening for a new door (i.e. constructing the wall stud frame), just reverse the measurements above (i.e. select your desired finished door height and add 2-1/2” to this measurement, then select your desire finished door width and add 2” to this measurement).

For Exterior Doors

  1. Measure the height of the rough opening, from the floor to the bottom of the upper stud of the opening (see the illustration below for this measurement). Measure the height on both corner edges of the opening, and then use the smallest of these two measurements. Then, subtract 3” from this height. This equals your needed door height.

Example: Rough opening height = 99”. Door height needed = 96”, or 8’/0” (99” – 3” = 96”, or 8’/0”)

  1. Measure the width of the rough opening, from inside of wall stud to inside of wall stud (see the illustration below for this measurement). Measure this in three places—top of the opening, middle of the opening, and bottom of the opening, and then use the smallest of these three measurements. Then, subtract 2” from this width. This equals your needed door width.

Example: Rough opening measurement = 38”. Door width needed = 36”, or 3’/0” (38” – 2” = 36”, or 3’/0”)

Rough Opening
Rough Opening

If you are framing the rough opening for a new Exterior door (constructing the wall stud frame), just reverse the measurements above (i.e. select your desired finished door height and add 3” to this measurement, then select your desire finished door width and add 2” to this measurement).

Why does the opening need to be larger than the door and its jamb? First, the additional space provides room to adjust the door and jamb to the rough opening. The stud wall structures of rough openings are not always plumb and square, so providing extra space allows the installer to “shim” the jamb for a perfectly plumb, level and square door installation. Second, the additional height allows space for flooring material above the sub-floor such as carpeting, wood, tile for Interior doors, or the threshold for Exterior Doors. Last, walls may expand and contract slightly with the natural humidity and moisture changes that occur with changing seasons. So the extra space allows for minor adjustments to your door fit, as necessary.

How Do I Measure Jamb Width?

To choose the proper jamb width for your pre-hung door, you must determine the thickness of the wall where your door will be placed. Wall thickness includes the wall stud plus the sheetrock thickness. Normally, either 2×4 or 2×6 studs are used for wall framing. Sheetrock is usually either 1/2” thick or 5/8” thick. Determine your wall stud and sheetrock thickness and then use the charts below to select the proper jamb width to match your application.

Interior Jamb Widths

Flat (non-Kerfed) Interior door jambs are available in the following widths, to match the following wall stud and sheetrock thicknesses:

Solid Knotty Alder, Flat Jamb w/Adjustable Stop:

Stud, Sheetrock Thickness Flat Jamb Width
2×4 Stud, 1/2” Sheetrock 4-5/8” Wide
2×4 Stud, 5/8” Sheetrock 4-7/8” Wide
2×6 Stud, 1/2” Sheetrock 6-5/8” Wide
2×6 Stud, 5/8” Sheetrock 6-7/8” Wide

Bull-nosed kerfed flat jambs for Interior doors are available in the following widths, to match the following wall stud and sheetrock thicknesses (Note: Kerfed flat jambs are more narrow than regular flat jambs, to allow for wrapping the drywall corner bead into the jamb):

Solid Knotty Alder, Bull-Nosed Kerfed Flat Jamb w/Adjustable Stop:

Stud, Sheetrock Thickness Flat Jamb Width
2×4 Stud, 1/2” Sheetrock 3-1/2” Wide
2×4 Stud, 5/8” Sheetrock 3-1/2” Wide
2×6 Stud, 1/2” Sheetrock 5-1/2” Wide
2×6 Stud, 5/8” Sheetrock 5-1/2” Wide

Exterior Jamb Widths

Rabbeted jambs for Exterior doors are available in the following widths, to match the following wall stud and sheetrock thicknesses:

Solid Knotty Alder, Rabbeted Jamb:

Stud, Sheetrock Thickness Rabbeted Jamb Width
2×4 Stud, 1/2” Sheetrock 4-5/8” Wide
2×4 Stud, 5/8” Sheetrock 4-7/8” Wide
2×6 Stud, 1/2” Sheetrock 6-5/8” Wide
2×6 Stud, 5/8” Sheetrock 6-7/8” Wide

How Do I Choose Door Handing and Swing?

Handing & Swing refers to the side of the door which is hinged, and the way the door swings inside or outside of the room or home. Consider the way you would like your door to open when making this choice.

A simple way to understand handing is to stand in the doorway with your back against the jamb of the door where you want the hinges to be placed. From this position, if you want the door on the on your left, it is a left hand door. From this position, if you want the door on your right, it is a right hand door.

Next, determine if you want the door to swing inside or outside the room or home. Inside is an “inswing” door, and outside is an “outswing” door. Review the illustrations below to identify the way you would like your door to be handed and swing (Note:  These illustrations apply to Interior or Exterior single doors).

Single Door, Left Hand Inswing
Single Door, Left Hand Inswing
Single Door, Right Hand Inswing
Single Door, Right Hand Inswing
Single Door, Left Hand Outswing (sometimes called Right Hand Reverse)
Single Door, Left Hand Outswing (sometimes called Right Hand Reverse)
Single Door, Right Hand Outswing (sometimes called Left Hand Reverse)
Single Door, Right Hand Outswing (sometimes called Left Hand Reverse)

For Interior or Exterior double doors, one door is designated as “active” (operating knob or handle to open the door), and the other door is designated as “inactive” (still opens and closes, but no working knob or handle). The inactive door includes an attached T-astragal with flush bolts (top only for Interior doors, and both top and bottom for Exterior doors) to secure the door in the closed position. Review the illustrations below to select which side of your double door you would like active, and its handing and swing (inside or outside of the room or home).

Double Door, Left Hand Active, Inswing
Double Door, Left Hand Active, Inswing
Double Door, Right Hand Active, Inswing
Double Door, Right Hand Active, Inswing
Double Door, Left Hand Active, Outswing (sometimes called Double Door, Right Hand Reverse)
Double Door, Left Hand Active, Outswing (sometimes called Double Door, Right Hand Reverse)
Double Door, Right Hand Active, Outswing (sometimes called Double Door, Left Hand Reverse)
Double Door, Right Hand Active, Outswing (sometimes called Double Door, Left Hand Reverse)

In addition to these handing & swing options, we also offer Interior double doors with a “ball catch” or a “bipass” configuration. These double door options are most frequently used on closet door applications. For example, ball catches are typically used with “dummy” (non-active) handle sets, on outswing closet doors. Ball catch hardware is included at no additional charge on double ball catch doors, and track hardware is provided at no additional charge on double bipass doors. We do not bore for the dummy handle sets on these options. Review the illustrations below to select one of these Interior double door applications.

Double Ball Catch
Double Ball Catch
Double Bipass
Double Bipass

How Do I Choose the Right Bore Position? 

The bore position for your new door depends upon the type and function of the hardware (knob or handle) you desire to use on the door. Consult your hardware supplier for their recommendations. When you order a pre-hung door, we can bore your new door for a handle or lockset, at no extra charge. Our standard bore options and dimensions are documented in this section.

We offer both single bore and double bore options. Double bores are typically used on Exterior doors, with a lockset with deadbolt. Our bores include mortising the edge of the door for the latch (latch and dead bolt for double bore), and mortising the “strike” on the jamb leg where the latch inserts (or latch and deadbolt for double bore).

The knob or handle bore is 36” from the bottom of the door to the center of the bore hole, and the bore hole is 2-1/8” in diameter. For double bore options, the distance between the two bore holes is always 5-1/2” center to center (from the center of the diameter of the knob or handle bore to the center of the diameter of the dead bolt bore). Available “backsets” (the distance from the edge of the door to the center of the bore diameter) are:

Available Backsets

2-3/8”
2-3/4”

Review the following illustrations to select the bore and backset you desire for your new door.

Single Bore, 2-3/8” Backset
Single Bore, 2-3/8” Backset
Single Bore, Latch Mortis
Single Bore, Latch Mortis
Single Bore, 2-3/4” Backset
Single Bore, 2-3/4” Backset
Double Bore, 2-3/8” Backset
Double Bore, 2-3/8” Backset
Double Bore, Latch Mortis
Double Bore, Latch Mortis
Double Bore, 2-3/4” Backset
Double Bore, 2-3/4” Backset

How Do I Install My Interior Door? 

Step-by-step instructions for installing a pre-hung and pre-finished Interior door are provided in this section. We assume no liability associated with following these instructions, and strongly suggest that you consult a professional contractor for door installation. The skill level for this installation is “Intermediate”.

Tools Required

  • 6′ Level
  • Hammer
  • Drill
  • Tape Measure

Materials Required

  • Interior door, pre-hung and pre-finished
  • Shims
  • 2-1/2″ Finishing Nails
  • 2-1/2″ Screws

Step-by-Step Instructions

  1. Place the door and jamb unit in the opening. Position the pre-hung door unit in the rough opening. Center the unit so that equal spacing exists between the unit and the wall studs or wall structure on each side.
  2. Shim the hinge side of the door. Shims should be used to fill the open space between the door jamb and wall on the hinge side of the unit. Place shims between the door unit and wall at each hinge location.
  3. Temporarily secure the door in the opening. Ensure that the door unit is flush with the face of the sheet rock, front and back. Pre-drill a hole through the door stop at the top hinge shim. Nail one 2-1/2″ finishing nail in this hole to temporarily hold the door in place.
  4. Verify that the hinge side of the door is square and plumb. Using a 6′ level placed on the front face of the hinge side of the jamb, verify that the jamb is square. Adjust the middle and lower hinge shims until the bubble on the level is exactly in the center. After the hinge side of the jamb is square, check for plumb on the jamb. Rotate the level so it is sitting flat along the front edge of the hinge side of the jamb. Again ensure that the associated bubble on the level is exactly in the center.
  5. Secure the jamb on the hinge side. Once the hinge side of the jamb is square and plumb, pre-drill holes through the stop at both the center and bottom hinges. Nail 2-1/2″ finishing nails through these holes to secure the hinge side of the jamb in place.
  6. Shim the strike side of the door. Shim the strike side (latch side) of the door unit, placing shims at the top, center, and bottom of the unit between the jamb and wall.
  7. Verify the strike side of the door is square and plumb. Using a 6′ level placed on the face of the strike side of the jamb, verify that the jamb is square. Adjust the middle and lower strike side shims until the bubble on the level is exactly in the center. After the strike side of the jamb is square, check for plumb on the jamb. Rotate the level so it is sitting flat along the front facing edge of the strike side of the jamb. Again ensure that the associated bubble on the level is exactly in the center.
  8. Secure the jamb on the strike side. Once the strike side of the jamb is square and plumb, pre-drill holes through the jamb at both the center and bottom of the strike side of the jamb. Nail 2-1/2″ finishing nails through these holes to secure the strike side of the jamb in place.
  9. Verify width measurements. Using the tape measure, verify that the distance between the hinge jamb and strike jamb is the same at the top, center, and bottom of the jamb. Carefully remove temporary nails and add or remove shims to adjust for equal distance at each position. Replace temporary nails after adjustment.
  10. Shim the header (top) of the jamb. Place shims in two equal positions on the top of the door unit, between the header (top) of the jamb and the wall above. Adjust the shims until an even margin (called the “reveal”) exists between the door and the jamb across the top of the door.
  11. Secure the jamb header (top). Pre-drill holes through the door stop in the location of each of the two shims on the head (top) of the unit. Nail 2-1/2” finishing nails through these holes to secure the head of the jamb into place.
  12. Verify the “reveal”. Close the door and check to ensure that equal spacing exists between the door and jamb at the top and along both sides (again, called the “reveal”). Adjust shims at any position until equal spacing is achieved.
  13. Secure the unit with additional finishing nails. After verification of an even reveal, a second set of nails is needed to secure the jamb. Open the door and, on the hinge side of the jamb, place a second 2-1/2” finishing nail next to the stop but on the narrow side of the jamb, for each of the three shim positions. Repeat this on the strike side of the door jamb. When all finishing nails have been installed, use a nail to counter sink the heads of all finishing nails.
  14. Replace center screws on the hinges. Once the second set of finishing nails are in place, remove the center hinge screw(s) from the top hinge where the hinge secures to the jamb (not where the hinge is attached to the door). Replace the screw(s) with a 2-1/2” screw(s). Repeat this step on the center and bottom hinges (again, jamb side of the hinge only).

The Interior door is now installed, and case moulding (if applicable) can be installed.

For Exterior door installation, we strongly suggest that you consult a professional contractor.

How Do I Care for My Door? 

Under normal conditions, all wood products contain some moisture, and wood readily exchanges moisture with the environment. This is true of all wood products, whether they are raw (unfinished) or finished. Although a finish will slow this process, wood will regardless react to changes in humidity and environment.

Wood does not change size or shape unless its moisture content changes due to humidity conditions of the environment. When humidity conditions are high, wood absorbs moisture and swells (or expands). In low humidity conditions, wood releases moisture and shrinks (or contracts).

Wood products perform successfully when correctly used in a proper environment. We select and use kiln-dried woods with a 5%-8% moisture content to ensure stability in climate controlled homes. Relative humidity inside the home should be maintained within a range of 40%-50%. Homes without proper temperature and climate control will likely experience problems with dimensional change of the wood. Care should especially be taken during site storage and installation. Other points to consider:

  • Extreme moisture or dryness will cause panel expansion or contraction, joint separation, veneer checking or cracking, delaminations, bowing of the stile/rail, expansion or contraction of the stile/rail, and may include door failure. In Exterior applications, if the door will be exposed to frequent direct sunlight or moisture, we recommend that a non-wood product be used instead of wood.
  • In seasonal climates doors may expand and bind against their jambs during the more humid seasons. Likewise, doors may pull away from their jambs during the dry seasons.
  • If a door needs to be trimmed for fitting purposes, all exposed edges must be sealed and refinished immediately.
  • Doors with a painted finish will reveal “seams” at the joints as natural wood movement occurs.
  • If doors are ordered unfinished from the factory, doors should be completely finished on all six sides within 14 days of delivery. Finishing/sealing the door will minimize and slow the absorption of moisture but it will not eliminate it, so proper humidity levels are important throughout the period of storage, installation, and use.

Factory Unfinished Doors (Machine-Sanded)

If you order your doors unfinished from the factory, the center panels will be individually machine-sanded, and after assembly, the entire door will be machine-sanded to flush the joints and create a smooth, uniform surface. Additional hand-sanding is required at the jobsite before finishing in order to remove handling marks, oil residue from fingerprints, surface blemishes, and other minor imperfections. Sun Mountain is not responsible for the appearance of any door not finished at our factory. We believe that the overall quality of the finish is primarily and directly related to the quality of the pre-finishing sanding process, and we recommend that onsite finishers follow the same process that we use in our factory pre-finished doors.

Factory Pre-Finished Doors

We believe that the final quality of the finish is directly related to and perhaps most importantly affected by the quality of the sanding prior to the first coating application. A bad finish can almost always be traced back to a combination of poor or non-existent hand sanding, poor finishing materials, and/or a poor work environment. After machine-sanding, our doors are hand-sanded with 180 grit sand paper using rotary orbital sanders, at lease 30 minutes per door. Sticking and panel profile details are then finger-sanded, with particular attention given to the exposed end grain on the tops and bottoms of the panels. Minor dings and dents are repaired with a very little bit of water, a hot iron, and light sanding. Our stain is applied by a HVLP (High Volume, Low Pressure) spray gun in a climate-controlled spray booth with an air make-up system, allowed to penetrate the wood, and air-dry. A protective, catalyzed-conversion varnish sealer is then sprayed on all six sides of the door and allowed to air-dry. After drying, the entire door is fine-sanded by hand (again with 180 grit sand paper) to achieve an ultra-smooth surface for the topcoat. Glazes (as applicable) are then brushed-on and wiped-off by hand, using the artist’s discretion for highlighting and shadow. Finally, a durable, cabinet-quality, catalyzed conversion varnish top coat is sprayed, which when dry provides a beautiful finish that not only protects against scratches, nicks and dents, but is impervious to both moisture and virtually all household chemicals. Exterior top coats include an UV (Ultra-Violet) light inhibitor.

Finish Maintenance

All finished wood requires regular maintenance to keep the finish looking as new as possible. For Interior doors, dust regularly and periodically wipe with a damp (not wet) cloth to remove dirt and other particles and smudges. Furniture and other wood polishes are not recommended as they will create build-up on the finish. For Exterior doors, the speed at which the finish will deteriorate is in direct response to the exposure of the door to direct sunlight, rain, and snow. Most Exterior finishes deteriorate rapidly. At a minimum, we recommend that Exterior doors be inspected and wiped down every six months, in spring and fall, with a damp (not wet) cloth to remove dirt and other particles. Depending on exposure and weather conditions, Exterior doors may need to be refinished as often as every year. To refinish, we recommend using a high-quality Exterior lacquer or varnish system, closely following the manufacturer’s instructions for refinishing.

What is the Warranty on My Door?

ONE-YEAR LIMITED WARRANTY ON UNFINISHED DOORS
FIVE-YEAR LIMITED WARRANTY ON FACTORY PRE-FINISHED INTERIOR DOORS

Sun Mountain doors are warranted to be of sound material and workmanship and to be free of defects which would cause the door to be unfit for ordinary recommended use for the period of twelve (12) months from the date of shipment. In addition, interior doors which have been pre-finished by Sun Mountain are warranted for an additional four (4) years. This extended warranty applies only to the construction of the door, and not the factory pre-finish itself. See Sun Mountain’s “Finishing and Care Instructions” for details on finish maintenance.

If a defect occurs within one year from the date of shipment, written notice of the defect must be provided to Sun Mountain. Buyer shall not return any goods until Sun Mountain has been provided a reasonable opportunity to inspect the goods at Buyer’s premises to determine whether a defect exists. Sun Mountain will not be liable for any doors repaired, returned, or replaced without prior written consent. If warranted doors contain defects covered under this limited warranty, Sun Mountain shall be limited to, at Sun Mountain’s option, 1) repairing or replacing the doors or 2) refunding the purchase price of the doors to Buyer. Doors will be repaired or replaced in the same stage of fitting and/or finishing as they were originally supplied. Sun Mountain will not pay any cost to remove defective doors or to install new doors, and will not be responsible for any finishing costs or consequential damages. Final warranty inspection will be made at Sun Mountain’s location, upon receipt of defective product. If the claim is found by Sun Mountain, in its sole discretion, to be invalid, neither repair/replacement nor refund will be issued.

This limited warranty does NOT apply to any of the following:

  • Doors more than 8’ tall or 3’6” wide
  • Lited doors or one-panel wood doors over 6’8” tall or 3’ wide
  • Doors that have warp which does NOT exceed 1/4” in the plane of the door (see below)
  • Doors less than 1-3/4” thick for exterior use
  • Doors which have not been properly sealed on all six sides within 14 days of delivery, including the top and bottom edges of the door
  • Damage caused by failure to comply with Sun Mountain’s “Finishing and Care Instructions”
  • Damage due to improper or incorrect installation
  • Exterior doors used in a commercial application
  • Damage caused by others or by any cause beyond the control of Sun Mountain, including but not limited to damage caused by misuse, abuse, accident, mishandling or by fire, flood, earthquake, storm, tornado or other acts of nature
  • Misuse of a door, including but not limited to, using a door in an exterior application without adequate overhang, or with an inappropriate exterior finish color (Note:  Adequate overhang depends on the typical weather conditions of the site where the building is located, but generally means an overhang projecting a distance away from the door at least equal to one-half the elevation difference between the bottom of the door and the base of the overhang structure. In order to reduce the chance of warping or checking, dark-colored finishes should be avoided on all exterior surfaces, especially if the door is exposed to direct sunlight.)
  • Discoloration or rusting of decorative metal accents (clavos, grills, strap hinges, etc.)
  • Damage due to trimming the door more than 1/2” from the top or 1-1/2” from the bottom of the slab
  • Panel movement or shrinkage (Note:  Panels in Sun Mountain doors are designed to “float”, and will expand or contract in response to environmental conditions)
  • Expansion or contraction due to varying environmental conditions, such as temperature and humidity
  • Gates, or doors used in gate applications
  • The appearance of any field finished door

In addition, the following natural properties and characteristics add to the beauty of wood doors and are not considered defects:

  • On all knotty wood species, knots which show light through the door will be filled and knots which do not show light through the door and are not filled should be expected and are not considered defects (Note:  On knotty wood species, the location, quantity, and size of knots is unpredictable)
  • On all wood species, natural variations in the color, texture, and density of the wood is common and always acceptable
  • On wire brushed doors, an inconsistent face plane where stiles or mullions meet rails is acceptable to a depth change of 1/16″, and an apparent open connection between stiles and rails is acceptable to a width of 1/32″
  • On cedar doors, surface checks of up to 1/32″ in width are acceptable and do not compromise the structural integrity of the door

For the purposes of this warranty, warp is defined as any distortion in the door itself and does not refer to the relationship of the door to the frame or jamb in which it is hung. The term “warp” includes bow, cup and twist. In measuring the amount of warp in a door, the following method shall be used: Bow, cup and twist shall be measured by placing a 7′ straightedge on the suspected concave face of the door at any angle with the door in its installed position. The measurement of warp shall be made at the point of maximum distance between the bottom of the straightedge and the face of the door.

If the claimed defect is warp, Sun Mountain may defer replacing or refunding the door for a period of up to twelve (12) months from the date of claim or date of installation, in order to permit conditioning and equalizing to humidity and temperature conditions. The deferral period will not be counted against the one-year warranty period.

Note: This warranty is effective for all products manufactured or sold after August 1, 2004.