What is the rough opening for a 36 inch door?

It depends on the unit, not the slab. Masonite's entry chart shows a 3'0" by 6'8" exterior door in a 37 1/2 by 81 1/2 in unit, with a printed rough opening of 38 1/4 by 82 in. JELD-WEN's exterior minimum, at least 3/4 in larger each way, would make the height 82 1/4 for a unit that size.

What is the rough opening for a 32 inch interior door?

Measure the unit and add 1/2 in each way, which Masonite and JELD-WEN both print. Masonite's allowance table gives a 34 in rough opening width for units from 32 to 33 1/2 in wide, and 82 in high for its 81 1/2 in units.

How much bigger should a rough opening be than the door?

Interior prehung, 1/2 in in width and height over the unit from both major makers. Exterior prehung, JELD-WEN says a minimum of 3/4 in both ways, and Masonite's entry chart uses 3/4 in wide and 1/2 in high.

Does the building code set door rough opening sizes?

No. The rough opening is a manufacturer's installation requirement. The code sets clear width and height for the one required egress door, IRC R311.2, measured to the stop, and exempts every other door.

How long should a door header be?

The rough opening width plus one jack stud at each end. For a 38 1/4 in opening with single 2x jack studs that is 41 1/4 in. The header's depth is a span question, answered by header tables rather than by the door.

Is Masonite's rough opening chart wrong?

Three of its 36 entry unit rows do not follow the 3/4 in width allowance every other row uses. The 2'8" door with one 12 in sidelite is printed at a 45 3/4 in rough opening for a 47 in unit. The chart itself says it is for reference only, and to check dimensions for the specific order.

How much does it cost to install a door?

HomeAdvisor's June 2026 guide puts interior doors at $375 to $1,125 and exterior doors at $550 to $2,000 per door, including the door, hardware and labor. Replacing the frame adds $200 to $650.

Do I need a sill pan under an exterior door?

JELD-WEN's exterior instructions include one as a step and note that it reduces the height clearance of the rough opening. Your jurisdiction's flashing requirements and the door's own instructions govern.

How much does a new front door cost?

A front door is an exterior door, and HomeAdvisor's June 2026 guide gives $550 to $2,000 per exterior door installed, including the door, hardware and labor. Replacing the front door frame as well adds $200 to $650, and hauling away the old door adds $40 to $200.

How much does it cost to replace a sliding patio door?

HomeAdvisor's sliding glass door guide gives $1,169 to $4,145 installed. By frame material it prices vinyl at $300 to $1,200, aluminum at $750 to $2,500, wood at $1,000 to $3,000 and fiberglass at $1,500 to $2,500. Cutting a new opening for a patio door where there was none adds $1,000 to $3,600.

How much does a bedroom door cost?

A bedroom or closet door is an interior door, which HomeAdvisor prices at $375 to $1,125 per door installed, including hardware and labor. If it is a prehung unit, frame the rough opening at the unit size plus 1/2 in each way, the allowance both Masonite and JELD-WEN print.

Does a wooden or steel door cost more to install?

HomeAdvisor's door installation guide prices doors as interior or exterior, $375 to $1,125 and $550 to $2,000 installed, and does not split either range by material. A steel entry door and a wooden one fall in the same exterior row. The only material split on this page is for sliding glass doors, where a wood frame is $1,000 to $3,000 against $300 to $1,200 for vinyl.

How much does a bedroom or interior door cost?

HomeAdvisor's June 2026 guide gives $375 to $1,125 per interior door installed, and $200 to $650 more if the frame has to be replaced.

How much does a security door cost to install?

HomeAdvisor's June 2026 guide averages a security screen door at $350, with installation labor at $50 to $200 per door.

How much does barn door installation cost?

HomeAdvisor's June 2026 guide gives $1,350 to $5,000 for a typical project, $200 to $1,600 for a single interior barn door installed and $500 to $3,400 for a double one.

How much does an exterior or interior French door cost?

HomeAdvisor's June 2026 guide gives $400 to $4,000 for a French door, and $1,550 to $6,250 for a typical patio door replacement. The guide does not price interior and exterior French doors separately.

How much does a sliding screen door or sliding shower door cost to install?

HomeAdvisor's June 2026 guide averages a sliding screen door at $175, with installation labor at $50 to $200. For a shower, HomeAdvisor's June 2026 guide gives $530 to $1,391 for a typical glass shower door job.

How much does it cost to hang a bathroom, basement or exterior door?

HomeAdvisor's June 2026 guide gives $375 to $1,125 per interior door installed, which covers a bathroom or basement door, and $550 to $2,000 for an exterior door, a metal door included. Replacing the frame adds $200 to $650.

How much does a handyman charge to install a storm door?

HomeAdvisor's June 2026 guide gives $187 to $683 for a typical storm door installed, and $200 to $525 for a full-view door. The guide does not separate a handyperson's price from a contractor's.

Home › Windows and doors › Door Rough Opening Calculator

Door Rough Opening Calculator

Masonite and JELD-WEN installation instructions, read side by side

No building code sets a door's rough opening. The two biggest US door makers set it in their installation sheets, and they agree on interior doors, half an inch each way, and disagree on exterior height by a quarter inch. Masonite's entry door chart also breaks its own rule on three rows, and on one of them it prints a rough opening an inch and a quarter narrower than the door unit it belongs to.

Rough opening from the unit you are installing

Door

Unit width (outside of the frame)

Unit height (floor to top of head jamb)

Jack stud thickness (0 to skip the header)

Doors in the job (for the price table below)

no.

Measure the unit, the door hung in its frame, across the outside of the jambs and from the floor to the top of the head jamb. The slab size is not enough: frame thickness varies by product.

Specification summary

Generated from on . Reopen that address to reproduce these figures exactly.

Entered

Result

The door unit in its rough opening

Door installation prices

Per door, materials and labor
Item	Low	High	Unit
Interior door	$375	$1,125	per door, installed
Exterior door	$550	$2,000	per door, installed
Replacing the door frame	$200	$650	added
Hauling away the old door	$40	$200	added

Source: HomeAdvisor, how much does door installation cost. Last price check: September 13, 2026.

The source states that its interior and exterior ranges include the door itself, supplies, hardware and labor. It also prints an overall range of $497 to $1,960 and an average of $1,218 without saying whether those are per door or per project, so they are left out here. The frame and haul-away rows are extras on top of a door, not alternatives to one.

Screen door prices

Average, each
Item	Low	High	Unit
Hinged screen door	$200	$200	average
Sliding screen door	$175	$175	average
Retractable screen door	$800	$800	average
Security screen door	$350	$350	average
Garage screen door	$900	$900	average
Installation labor	$50	$200	per door
Removing the old door	$125	$125	average

Source: HomeAdvisor, how much does screen door installation cost. Last price check: September 13, 2026.

Door prices are published as averages, not ranges. The same page gives $100 to $1,500 in its headline and $75 to $2,500 in its overview.

Sliding glass door prices

As each row states
Item	Low	High	Unit
Sliding glass door, installed	$1,169	$4,145	total
60 x 80 in door	$1,000	$1,000	average
72 x 80 in door	$1,200	$1,200	average
96 x 82 in door	$1,600	$1,600	average
144 x 96 in door	$2,900	$2,900	average
Vinyl frame	$300	$1,200	door
Aluminum frame	$750	$2,500	door
Wood frame	$1,000	$3,000	door
Fiberglass frame	$1,500	$2,500	door
Cutting a new opening	$1,000	$3,600	total

Source: HomeAdvisor, how much does a sliding glass door cost. Last price check: September 13, 2026.

The source starts a vinyl sliding door at $300, below its smallest door size at $1,000.

Storm door prices

Installed, as each row states
Item	Low	High	Unit
Storm door, typical	$187	$683	total
Storm door, full range	$100	$1,800	total
High-view	$150	$325	installed
Mid-view	$160	$300	installed
Full-view	$200	$525	installed
Half	$200	$600	installed
Low-E glass, full-view	$225	$575	installed
Beveled glass	$250	$605	installed
Retractable screen	$250	$600	installed
Double	$600	$1,100	installed
Old door removal and disposal	$50	$100	total

Source: HomeAdvisor, how much does a storm door cost. Last price check: September 15, 2026.

The source's headline range is $187 to $683 and its summary gives $100 to $1,800; both are shown.

Pocket door prices

As each row states
Item	Low	High	Unit
Pocket door, typical project	$800	$2,500	total
32 in, new construction	$450	$1,500	total
32 in, remodel	$1,350	$2,200	total
36 in, new construction	$550	$1,850	total
36 in, remodel	$1,550	$2,950	total
60 in, new construction	$800	$3,300	total
60 in, remodel	$1,700	$4,200	total
Wall demolition	$1,200	$2,500	total
HVAC relocation	$450	$2,200	total

Source: HomeAdvisor, how much does a pocket door cost. Last price check: September 15, 2026.

The remodel rows start $900 to $1,000 above the new construction rows, less than the source's own $1,200 to $2,500 for opening the wall.

Barn door prices

Installed, as each row states
Item	Low	High	Unit
Barn door, typical project	$1,350	$5,000	total
Single barn door	$200	$1,600	installed
Double barn door	$500	$3,400	installed
Interior	$200	$2,500	installed
Exterior	$1,000	$5,000	installed
36 x 84 in	$300	$3,000	installed

Source: HomeAdvisor, how much does a barn door cost. Last price check: September 15, 2026.

The typical range starts at $1,350 while the source's own single door and interior rows start at $200.

Patio and French door prices

As each row states
Item	Low	High	Unit
Patio door replacement, typical	$1,550	$6,250	total
French door	$400	$4,000	total
Sliding door	$1,000	$3,000	total
Telescoping door	$1,500	$5,000	total
Folding glass doors	$3,000	$10,000	total
60 x 80 in, with installation	$350	$1,700	total
72 x 96 in, with installation	$500	$2,400	total
96 x 96 in, with installation	$650	$3,200	total
Labor	$400	$1,400	total

Source: HomeAdvisor, how much does patio door replacement cost. Last price check: September 15, 2026.

The size rows are labeled as including installation yet run $350 to $3,200, mostly below the typical replacement range.

Glass shower door prices

As each row states
Item	Low	High	Unit
Glass shower door, typical job	$530	$1,391	installed
Frameless	$300	$3,300	total
Semi-framed	$225	$2,200	total
Framed	$190	$500	total
Shower screen panel	$70	$300	total
30 x 72 in door	$390	$2,650	total
60 x 72 in door	$650	$3,150	total
Hardware pack and mounting clips	$150	$250	total

Source: HomeAdvisor, how much does a glass shower door cost. Last price check: September 15, 2026.

Frameless and custom doors share the same $300 to $3,300 range in the source's table.

Worked example

A 3'0" by 6'8" exterior prehung door, a Masonite unit measured at 37 1/2 by 81 1/2 in. Then the Masonite sidelite unit whose printed rough opening is too small.

Masonite's chart rule. Unit plus 3/4 wide and 1/2 high: 38 1/4 by 82 in, which is what its chart prints for this door.
JELD-WEN's minimum. Unit plus at least 3/4 each way: 38 1/4 by 82 1/4 in.
Frame to the larger. 38 1/4 by 82 1/4 in, leaving 3/8 in to shim each side.
Header. 38 1/4 plus a 1 1/2 in jack stud at each end: 41 1/4 in.
The bad row. A 2'8" door with a 12 in sidelite is a 47 in unit. The chart prints a rough opening of 45 3/4 in. The rule gives 47 3/4.

Two inches is the difference between the chart and a hole the unit fits, and the error is in the direction that stops the job. An opening a little big is shimmed. An opening too small means cutting studs back with the door on site.

The formula

The rough opening is the unit plus the maker's allowance. The header spans the opening and bears on the jack studs:

rough opening = unit + allowance shim each side = (rough opening − unit) ÷ 2 header = rough opening width + 2 × jack stud

unit: the door in its frame, outside of jamb to outside of jamb, floor to top of head
allowance, interior: 1/2 in each way, Masonite and JELD-WEN alike
allowance, exterior: JELD-WEN at least 3/4 in each way; Masonite's chart 3/4 wide and 1/2 high
jack stud: the stud under each end of the header, 1 1/2 in for a single 2x
sill pan: takes height from the opening; add its thickness

The header's size is a structural question this page does not answer. Its length is only arithmetic, and the header span tables on the header calculator take it from there.

Why this page reads the installation sheets

The usual answer to a door rough opening is a rule of thumb added to the slab size. Neither of the two largest manufacturers works that way. Both measure from the unit, because what matters is the frame, and frames differ.

Reading their sheets side by side shows where they agree, on interior doors, and where they do not, on exterior height. Checking the Masonite entry chart against its own allowance found three rows that break it, one with a rough opening smaller than the unit.

The site publishes no price of its own. The cost table quotes HomeAdvisor's per door ranges, bylined and dated.

Masonite entry door rough openings, checked against the chart's own rule
Masonite entry unit	Unit, in	Rough opening, in	Width allowance	Against the chart's own +3/4
Single 2'6" x 6'8"	31 1/2 x 81 1/2	32 1/4 x 82	+3/4 in	the rule
Single 2'8" x 6'8"	33 1/2 x 81 1/2	34 1/4 x 82	+3/4 in	the rule
Single 2'8" x 8'0"	33 1/2 x 97 1/2	34 1/4 x 98	+3/4 in	the rule
Single 3'0" x 6'8"	37 1/2 x 81 1/2	38 1/4 x 82	+3/4 in	the rule
Single 3'0" x 8'0"	37 1/2 x 97 1/2	38 1/4 x 98	+3/4 in	the rule
2'6" with one 10 in sidelite	43 x 81 1/2	43 3/4 x 82	+3/4 in	the rule
2'6" with one 12 in sidelite	45 x 81 1/2	45 3/4 x 82	+3/4 in	the rule
2'6" with one 14 in sidelite	47 x 81 1/2	47 3/4 x 82	+3/4 in	the rule
2'8" with one 10 in sidelite	45 x 81 1/2	46 1/4 x 82	+1 1/4 in	1 1/4 in, off the rule
2'8" with one 12 in sidelite	47 x 81 1/2	45 3/4 x 82	−1 1/4 in	NARROWER than the unit
2'8" with one 14 in sidelite	49 x 81 1/2	49 3/4 x 82	+3/4 in	the rule
2'8" x 8'0" with one 12 in sidelite	47 x 97 1/2	47 3/4 x 98	+3/4 in	the rule
2'8" x 8'0" with one 14 in sidelite	49 x 97 1/2	49 3/4 x 98	+3/4 in	the rule
3'0" with one 10 in sidelite	49 x 81 1/2	49 3/4 x 82	+3/4 in	the rule
3'0" with one 12 in sidelite	51 x 81 1/2	51 3/4 x 82	+3/4 in	the rule
3'0" with one 14 in sidelite	53 x 81 1/2	53 3/4 x 82	+3/4 in	the rule
3'0" x 8'0" with one 12 in sidelite	51 x 97 1/2	51 3/4 x 98	+3/4 in	the rule
3'0" x 8'0" with one 14 in sidelite	53 x 97 1/2	53 3/4 x 98	+3/4 in	the rule
2'6" with two 10 in sidelites	54 1/2 x 81 1/2	55 1/4 x 82	+3/4 in	the rule
2'6" with two 12 in sidelites	58 1/2 x 81 1/2	59 1/4 x 82	+3/4 in	the rule
2'6" with two 14 in sidelites	62 1/2 x 81 1/2	63 1/4 x 82	+3/4 in	the rule
2'8" with two 10 in sidelites	56 1/2 x 81 1/2	57 1/4 x 82	+3/4 in	the rule
2'8" with two 12 in sidelites	60 1/2 x 81 1/2	61 1/4 x 82	+3/4 in	the rule
2'8" with two 14 in sidelites	64 1/2 x 81 1/2	65 1/4 x 82	+3/4 in	the rule
2'8" x 8'0" with two 12 in sidelites	60 1/2 x 97 1/2	61 1/4 x 98	+3/4 in	the rule
2'8" x 8'0" with two 14 in sidelites	64 1/2 x 97 1/2	65 1/4 x 98	+3/4 in	the rule
3'0" with two 10 in sidelites	60 1/2 x 81 1/2	62 1/4 x 82	+1 3/4 in	1 3/4 in, off the rule
3'0" with two 12 in sidelites	64 1/2 x 81 1/2	65 1/4 x 82	+3/4 in	the rule
3'0" with two 14 in sidelites	68 1/2 x 81 1/2	69 1/4 x 82	+3/4 in	the rule
3'0" x 8'0" with two 12 in sidelites	64 1/2 x 97 1/2	65 1/4 x 98	+3/4 in	the rule
3'0" x 8'0" with two 14 in sidelites	68 1/2 x 97 1/2	69 1/4 x 98	+3/4 in	the rule
Double 5'0" x 6'8"	62 x 81 1/2	62 3/4 x 82	+3/4 in	the rule
Double 5'4" x 6'8"	66 x 81 1/2	66 3/4 x 82	+3/4 in	the rule
Double 5'4" x 8'0"	66 x 97 1/2	66 3/4 x 98	+3/4 in	the rule
Double 6'0" x 6'8"	74 x 81 1/2	74 3/4 x 82	+3/4 in	the rule
Double 6'0" x 8'0"	74 x 97 1/2	74 3/4 x 98	+3/4 in	the rule

Read 2026-09-13. Unit and rough opening sizes as printed on Masonite's 2017 entry systems chart. The allowance column is this page subtracting one from the other.

Download this table as CSV. Same cells as printed above, nothing added.

Two makers, four documents, and the allowance is not one number

No building code sets the size of a door's rough opening. It is whatever lets a particular frame be shimmed plumb and square, so it is printed in the manufacturer's instructions. The two largest US door makers were read side by side.

Interior prehung doors, they agree. Masonite:

check to make sure that the rough opening is 1/2" wider than the unit width & 1/2" higher than the unit height.

JELD-WEN says the same thing from the other side:

Verify the width and height of the door frame are each 1/2" smaller than the rough opening width/height.

Exterior doors, they do not. JELD-WEN sets a minimum, both ways:

Verify the width and height of the rough opening is a minimum of 3/4" larger than the door width and height.

Masonite's entry door chart, on every regular row, is 3/4 in wider and 1/2 in taller than the unit. Same width, a quarter inch less height. And JELD-WEN adds the detail that makes the quarter inch matter:

The use of a sill pan and other barriers will decrease the rough opening height clearance.

Neither document works from the slab. Both measure from the unit, the door already hung in its frame, because frame thickness varies by product. Masonite's chart shows a 3'0" by 6'8" entry slab in a unit 37 1/2 by 81 1/2 in and a rough opening of 38 1/4 by 82. Measure the unit you are buying.

The entry door chart that breaks its own rule, three times

Masonite's entry systems chart lists 36 units. On 33 of them the rough opening is the unit plus exactly 3/4 in wide. On three it is not, and one of those three is impossible:

Masonite entry systems, rough opening against unit, as printed. Width allowance is this page subtracting
Masonite entry unit	Unit, in	Rough opening, in	Width allowance	Against the chart's own +3/4
Single 2'6" x 6'8"	31 1/2 x 81 1/2	32 1/4 x 82	+3/4 in	the rule
Single 2'8" x 6'8"	33 1/2 x 81 1/2	34 1/4 x 82	+3/4 in	the rule
Single 2'8" x 8'0"	33 1/2 x 97 1/2	34 1/4 x 98	+3/4 in	the rule
Single 3'0" x 6'8"	37 1/2 x 81 1/2	38 1/4 x 82	+3/4 in	the rule
Single 3'0" x 8'0"	37 1/2 x 97 1/2	38 1/4 x 98	+3/4 in	the rule
2'6" with one 10 in sidelite	43 x 81 1/2	43 3/4 x 82	+3/4 in	the rule
2'6" with one 12 in sidelite	45 x 81 1/2	45 3/4 x 82	+3/4 in	the rule
2'6" with one 14 in sidelite	47 x 81 1/2	47 3/4 x 82	+3/4 in	the rule
2'8" with one 10 in sidelite	45 x 81 1/2	46 1/4 x 82	+1 1/4 in	1 1/4 in, off the rule
2'8" with one 12 in sidelite	47 x 81 1/2	45 3/4 x 82	−1 1/4 in	NARROWER than the unit
2'8" with one 14 in sidelite	49 x 81 1/2	49 3/4 x 82	+3/4 in	the rule
2'8" x 8'0" with one 12 in sidelite	47 x 97 1/2	47 3/4 x 98	+3/4 in	the rule
2'8" x 8'0" with one 14 in sidelite	49 x 97 1/2	49 3/4 x 98	+3/4 in	the rule
3'0" with one 10 in sidelite	49 x 81 1/2	49 3/4 x 82	+3/4 in	the rule
3'0" with one 12 in sidelite	51 x 81 1/2	51 3/4 x 82	+3/4 in	the rule
3'0" with one 14 in sidelite	53 x 81 1/2	53 3/4 x 82	+3/4 in	the rule
3'0" x 8'0" with one 12 in sidelite	51 x 97 1/2	51 3/4 x 98	+3/4 in	the rule
3'0" x 8'0" with one 14 in sidelite	53 x 97 1/2	53 3/4 x 98	+3/4 in	the rule
2'6" with two 10 in sidelites	54 1/2 x 81 1/2	55 1/4 x 82	+3/4 in	the rule
2'6" with two 12 in sidelites	58 1/2 x 81 1/2	59 1/4 x 82	+3/4 in	the rule
2'6" with two 14 in sidelites	62 1/2 x 81 1/2	63 1/4 x 82	+3/4 in	the rule
2'8" with two 10 in sidelites	56 1/2 x 81 1/2	57 1/4 x 82	+3/4 in	the rule
2'8" with two 12 in sidelites	60 1/2 x 81 1/2	61 1/4 x 82	+3/4 in	the rule
2'8" with two 14 in sidelites	64 1/2 x 81 1/2	65 1/4 x 82	+3/4 in	the rule
2'8" x 8'0" with two 12 in sidelites	60 1/2 x 97 1/2	61 1/4 x 98	+3/4 in	the rule
2'8" x 8'0" with two 14 in sidelites	64 1/2 x 97 1/2	65 1/4 x 98	+3/4 in	the rule
3'0" with two 10 in sidelites	60 1/2 x 81 1/2	62 1/4 x 82	+1 3/4 in	1 3/4 in, off the rule
3'0" with two 12 in sidelites	64 1/2 x 81 1/2	65 1/4 x 82	+3/4 in	the rule
3'0" with two 14 in sidelites	68 1/2 x 81 1/2	69 1/4 x 82	+3/4 in	the rule
3'0" x 8'0" with two 12 in sidelites	64 1/2 x 97 1/2	65 1/4 x 98	+3/4 in	the rule
3'0" x 8'0" with two 14 in sidelites	68 1/2 x 97 1/2	69 1/4 x 98	+3/4 in	the rule
Double 5'0" x 6'8"	62 x 81 1/2	62 3/4 x 82	+3/4 in	the rule
Double 5'4" x 6'8"	66 x 81 1/2	66 3/4 x 82	+3/4 in	the rule
Double 5'4" x 8'0"	66 x 97 1/2	66 3/4 x 98	+3/4 in	the rule
Double 6'0" x 6'8"	74 x 81 1/2	74 3/4 x 82	+3/4 in	the rule
Double 6'0" x 8'0"	74 x 97 1/2	74 3/4 x 98	+3/4 in	the rule

The 2'8" door with a 12 in sidelite is printed with a rough opening of 45 3/4 in for a unit of 47. A hole an inch and a quarter narrower than the door frame. The row above it, the same door with a 10 in sidelite, has 46 1/4, half an inch more than its rule would give. The 3'0" door with two 10 in sidelites is an inch over.

An oversize opening costs shims. An undersize one costs the job. A framer working to the 45 3/4 figure frames a wall the unit will not go into, and finds out on delivery day. The chart does carry a notice, and it is the right one:

Dimensions provided on this chart are for reference purposes only.

The calculator works from the unit you enter and flags any size that lands on one of these rows.

Measuring the unit, and the three places it goes wrong

Width across the outside of the jambs, not the casing and not the brickmold. Exterior units with brickmold attached are wider again: Masonite's chart puts the brickmold 2 1/2 in wider than the unit on every row.

Height from the bottom of the sill or jamb to the top of the head jamb. If the finished floor is not in yet, allow for it. A door framed to the subfloor and then given 3/4 in of hardwood and underlay loses that height at the bottom.

Check square before the unit goes in. JELD-WEN's sheets ask for the two diagonals of the rough opening to match, within 1/4 in on the exterior sheet, and for the opening to be plumb within 1/8 in on the interior sheet. A rough opening of the right size that is out of square still binds the door.

The one door the code does size

The code has no rough opening rule, but it does set a minimum for one door in a house, measured to trim rather than framing:

Egress door. Not less than one egress door shall be provided for each dwelling unit. The egress door shall be side-hinged, and shall provide a clear width of not less than 32 inches (813 mm) where measured between the face of the door and the stop, with the door open 90 degrees (1.57 rad). The clear height of the door opening shall be not less than 78 inches (1981 mm) in height measured from the top of the threshold to the bottom of the stop. Other doors shall not be required to comply with these minimum dimensions. Egress doors shall be readily openable from inside the dwelling without the use of a key or special knowledge or effort.

A 32 in door cannot give a 32 in clear width. The clear width is measured from the face of the open door to the stop, so the door's own thickness and the stop both come out of the slab width. The egress door has to be wider than the dimension it is required to provide.

Every other door in the house is exempt from both figures, which is why narrower interior doors are legal.

The sources, and where each one is hosted

Read 2026-09-13.

Installation Instructions for Interior Prehung Doors, Masonite, document 07-0035aHMD, printed 2/07, as hosted with the product listing by Home Depot. Step 1 sets the rough opening at 1/2 in wider and higher than the unit and prints a stud rough opening allowance table by unit width.

Rough Openings, Entry Systems New Construction Size, Masonite sizing chart, 2017, as hosted by the distributor Casco. Door unit actual size, rough opening (wood stud) and outside brickmold size for single, sidelite and double entry units.

Installation Instructions for Interior Pre-Hung Doors (JII109), JELD-WEN, dated 10/02/18, as hosted with the product listing by Home Depot. Rough opening inspection: frame 1/2 in smaller than the rough opening each way, square within 1/4 in, plumb within 1/8 in.

Installation Instructions for Pre-Hung Exterior Entry Doors (JII106), JELD-WEN, hosted on the manufacturer's own document store. Rough opening requirements: a minimum of 3/4 in larger than the door in width and height, square and plumb within 1/4 in, and a note that a sill pan reduces the height clearance.

Two of the four are hosted by a retailer and one by a distributor, because that is where the manufacturers' own installation sheets are published alongside the product. Each is the maker's own document with its own document number or date. Instructions change between product lines and years: the sheet that ships with your door governs.

The egress door text is IRC R311.2 as adopted in the 2018 Seattle Residential Code, read from the city's own PDF.

Frequently asked questions

What is the rough opening for a 36 inch door?: It depends on the unit, not the slab. Masonite's entry chart shows a 3'0" by 6'8" exterior door in a 37 1/2 by 81 1/2 in unit, with a printed rough opening of 38 1/4 by 82 in. JELD-WEN's exterior minimum, at least 3/4 in larger each way, would make the height 82 1/4 for a unit that size.
What is the rough opening for a 32 inch interior door?: Measure the unit and add 1/2 in each way, which Masonite and JELD-WEN both print. Masonite's allowance table gives a 34 in rough opening width for units from 32 to 33 1/2 in wide, and 82 in high for its 81 1/2 in units.
How much bigger should a rough opening be than the door?: Interior prehung, 1/2 in in width and height over the unit from both major makers. Exterior prehung, JELD-WEN says a minimum of 3/4 in both ways, and Masonite's entry chart uses 3/4 in wide and 1/2 in high.
Does the building code set door rough opening sizes?: No. The rough opening is a manufacturer's installation requirement. The code sets clear width and height for the one required egress door, IRC R311.2, measured to the stop, and exempts every other door.
How long should a door header be?: The rough opening width plus one jack stud at each end. For a 38 1/4 in opening with single 2x jack studs that is 41 1/4 in. The header's depth is a span question, answered by header tables rather than by the door.
Is Masonite's rough opening chart wrong?: Three of its 36 entry unit rows do not follow the 3/4 in width allowance every other row uses. The 2'8" door with one 12 in sidelite is printed at a 45 3/4 in rough opening for a 47 in unit. The chart itself says it is for reference only, and to check dimensions for the specific order.
How much does it cost to install a door?: HomeAdvisor's June 2026 guide puts interior doors at $375 to $1,125 and exterior doors at $550 to $2,000 per door, including the door, hardware and labor. Replacing the frame adds $200 to $650.
Do I need a sill pan under an exterior door?: JELD-WEN's exterior instructions include one as a step and note that it reduces the height clearance of the rough opening. Your jurisdiction's flashing requirements and the door's own instructions govern.
How much does a new front door cost?: A front door is an exterior door, and HomeAdvisor's June 2026 guide gives $550 to $2,000 per exterior door installed, including the door, hardware and labor. Replacing the front door frame as well adds $200 to $650, and hauling away the old door adds $40 to $200.
How much does it cost to replace a sliding patio door?: HomeAdvisor's sliding glass door guide gives $1,169 to $4,145 installed. By frame material it prices vinyl at $300 to $1,200, aluminum at $750 to $2,500, wood at $1,000 to $3,000 and fiberglass at $1,500 to $2,500. Cutting a new opening for a patio door where there was none adds $1,000 to $3,600.
How much does a bedroom door cost?: A bedroom or closet door is an interior door, which HomeAdvisor prices at $375 to $1,125 per door installed, including hardware and labor. If it is a prehung unit, frame the rough opening at the unit size plus 1/2 in each way, the allowance both Masonite and JELD-WEN print.
Does a wooden or steel door cost more to install?: HomeAdvisor's door installation guide prices doors as interior or exterior, $375 to $1,125 and $550 to $2,000 installed, and does not split either range by material. A steel entry door and a wooden one fall in the same exterior row. The only material split on this page is for sliding glass doors, where a wood frame is $1,000 to $3,000 against $300 to $1,200 for vinyl.
How much does a bedroom or interior door cost?: HomeAdvisor's June 2026 guide gives $375 to $1,125 per interior door installed, and $200 to $650 more if the frame has to be replaced.
How much does a sliding glass door cost?: HomeAdvisor's June 2026 guide gives $1,169 to $4,145 installed, averaging $1,200 for a 72 by 80 in door. By frame, vinyl is $300 to $1,200 and aluminum $750 to $2,500. Cutting a new opening in a wall adds $1,000 to $3,600.
How much does a security door cost to install?: HomeAdvisor's June 2026 guide averages a security screen door at $350, with installation labor at $50 to $200 per door.
How much does barn door installation cost?: HomeAdvisor's June 2026 guide gives $1,350 to $5,000 for a typical project, $200 to $1,600 for a single interior barn door installed and $500 to $3,400 for a double one.
How much does an exterior or interior French door cost?: HomeAdvisor's June 2026 guide gives $400 to $4,000 for a French door, and $1,550 to $6,250 for a typical patio door replacement. The guide does not price interior and exterior French doors separately.
How much does a sliding screen door or sliding shower door cost to install?: HomeAdvisor's June 2026 guide averages a sliding screen door at $175, with installation labor at $50 to $200. For a shower, HomeAdvisor's June 2026 guide gives $530 to $1,391 for a typical glass shower door job.
How much does it cost to hang a bathroom, basement or exterior door?: HomeAdvisor's June 2026 guide gives $375 to $1,125 per interior door installed, which covers a bathroom or basement door, and $550 to $2,000 for an exterior door, a metal door included. Replacing the frame adds $200 to $650.
How much does a handyman charge to install a storm door?: HomeAdvisor's June 2026 guide gives $187 to $683 for a typical storm door installed, and $200 to $525 for a full-view door. The guide does not separate a handyperson's price from a contractor's.

Check these numbers yourself

Installation Instructions for Interior Prehung DoorsMasonite, document 07-0035aHMD, printed 2/07, read 2026-09-13. Rough opening 1/2 in wider and higher than the unit, and a stud rough opening allowance table by unit width.
Rough Openings, Entry Systems New Construction SizeMasonite sizing chart, 2017, hosted by the distributor Casco, read 2026-09-13. Unit, rough opening and brickmold sizes for single, sidelite and double entry units.
Installation Instructions for Interior Pre-Hung Doors (JII109)JELD-WEN, dated 10/02/18, read 2026-09-13. Frame 1/2 in smaller than the rough opening each way.
Installation Instructions for Pre-Hung Exterior Entry Doors (JII106)JELD-WEN, read 2026-09-13. Rough opening a minimum of 3/4 in larger than the door in width and height; sill pan reduces height clearance.
Seattle Residential Code, Chapter 3, Section R311.2City of Seattle, adopting the 2018 IRC. Egress door clear width and height, measured to the stop.
How Much Does Door Installation Cost?HomeAdvisor, written by Timothy Moore, reviewed by Cati O'Keefe, updated 2026-06-20, read 2026-09-13. Per door installed ranges for interior and exterior doors.

How every figure here is verified: Sources & Method. Who builds this: Lucas Pradella, and the method is on About. Found something wrong? Tell us and it gets fixed or removed.

Figures on this page last checked against the source documents on 2026-09-13. Codes are amended locally; confirm against the edition your jurisdiction enforces.

Related calculators

Rough openings are quoted from the manufacturers' own installation documents, read on 13 September 2026. The instructions that ship with your door govern, and they change between product lines and years. The Masonite chart comparison is this page subtracting printed figures. Header sizing is structural and is not calculated here. Prices are HomeAdvisor's, not this site's.