Start from the rough opening
| Door width | Unit | Rough opening | Brickmould |
|---|---|---|---|
| 2/0 | 25.5 | 26.25 | 28 |
| 2/4 | 29.5 | 30.25 | 32 |
| 2/6 | 31.5 | 32.25 | 34 |
| 2/8 | 33.5 | 34.25 | 36 |
| 2/10 | 35.5 | 36.25 | 38 |
| 3/0 | 37.5 | 38.25 | 40 |
| 3/6 | 43.5 | 44.25 | 46 |
Ordering a prehung exterior entry door starts with three distinct sets of dimensions that homeowners and sales quotes frequently mix up: the nominal callout size of the slab (such as 3/0 at 6/8 height), the outside frame or unit dimension of the prehung jamb assembly, and the framed rough opening inside the wall cavity after interior casing trim is pulled back. A prehung unit cannot fit into a rough opening that is narrower or shorter than the required opening dimension, and an oversized opening leaves a framing gap that must either be shimmed or widened to the next listed door size.
To make that geometry concrete, the table above transcribes all seven published inswing single-door widths at 6/8 height from Therma-Tru’s Unit and Rough Opening Sizing sheet (read October 19, 2026). At the 6/8 height, the outside unit height is 81.625 in, the required rough opening height is 82 in, and the exterior brickmould height is 82.875 in. Across the seven single-door widths in that table, each listed callout adds 0.75 in between the unit width and the required rough opening width, and steps up again to the exterior brickmould width:
- 2/0 callout: 25.5 in unit width, 26.25 in rough opening width, 28 in brickmould width.
- 2/4 callout: 29.5 in unit width, 30.25 in rough opening width, 32 in brickmould width.
- 2/6 callout: 31.5 in unit width, 32.25 in rough opening width, 34 in brickmould width.
- 2/8 callout: 33.5 in unit width, 34.25 in rough opening width, 36 in brickmould width.
- 2/10 callout: 35.5 in unit width, 36.25 in rough opening width, 38 in brickmould width.
- 3/0 callout (default): 37.5 in unit width, 38.25 in rough opening width, 40 in brickmould width.
- 3/6 callout: 43.5 in unit width, 44.25 in rough opening width, 46 in brickmould width.
When you enter your measured rough opening width and height, the calculator finds the largest published Therma-Tru row whose required rough opening width does not exceed your measured width, reports the remaining horizontal gap between your opening and that row’s rough opening, and—when no row fits, or when the next larger listed unit’s required rough opening is closer to your measured width than the fitting unit’s rough opening—names that larger size and the exact width increase needed to step up to it. In the default configuration, a 38.25 in by 82 in rough opening matches the 3/0 unit (37.5 × 81.625 in) with 0 in of width gap and 0 in of height gap. If your measured rough opening is 37.5 in wide by 82 in tall, it sits between two listed sizes: the largest fitting unit is the 2/10 door (35.5 in unit width, 36.25 in required rough opening), leaving a 1.25 in width gap, or you can widen the rough opening by 0.75 in (to 38.25 in) to fit the 3/0 door. If your rough opening is 50 in wide by 82 in tall—wider than the widest 3/6 single door (44.25 in rough opening)—the calculator matches the 3/6 unit with a 5.75 in width gap and notes that no wider single door is listed in the table. Along the vertical axis, if your rough opening height is 81 in instead of 82 in, the calculator flags that the opening is short by 1 in for a 6/8 unit. Note that these rows come from one manufacturer’s table; other door makers publish their own unit and rough opening dimensions.
Check the quoted door against ENERGY STAR
| Glazing level | U-factor, at most | SHGC, at most |
|---|---|---|
| Opaque | 0.17 | No rating |
| ½-lite or less | 0.23 | 0.23 |
| More than ½-lite, Northern and North-Central | 0.26 | 0.4 |
| More than ½-lite, South-Central and Southern | 0.28 | 0.23 |
Swinging doors also need an air leakage rating of at most 0.5 cfm per sq ft (Table 5). A door with at most 900 sq in of glazing counts as ½-lite or less.
Ask the dealer for the NFRC label values of the exact door unit on your quote—its U-factor, its Solar Heat Gain Coefficient (SHGC), and its swinging-door air leakage rating in cfm per sq ft—and enter them into the calculator.
The calculator compares your entered NFRC values against Table 2 and Table 5 of the ENERGY STAR Program Requirements for Residential Windows, Doors, and Skylights, Version 7.0 (read October 19, 2026). Under Table 2, the maximum U-factor and SHGC depend on the door’s glazing level—where a door with up to 900 sq in of glass counts as ½-lite or less—and climate zone applies only when glazing exceeds ½-lite:
- Opaque doors (no glass): U-factor must be at most 0.17, and SHGC has no rating requirement. In our test suite, an opaque door entered with U-factor 0.17 and air leakage 0.5 cfm per sq ft passes every applicable check and meets the table.
- ½-lite or less (up to 900 sq in of glass): U-factor must be at most 0.23 and SHGC must be at most 0.23 across all climate zones. Entering U-factor 0.23 and SHGC 0.23 passes both Table 2 checks, while leaving air leakage blank keeps the overall table verdict open until the air leakage rating (at most 0.5 cfm per sq ft) is entered.
- More than ½-lite (over 900 sq in of glass): In the Northern and North-Central zone, U-factor must be at most 0.26 and SHGC at most 0.40. In the South-Central and Southern zone, U-factor must be at most 0.28 and SHGC at most 0.23. For example, a more-than-½-lite door in the South-Central or Southern zone with U-factor 0.27 and SHGC 0.25 passes the 0.28 U-factor limit but fails the 0.23 SHGC limit, so the unit fails the table even before air leakage is entered.
Table 5 of Version 7.0 requires swinging doors to have an air leakage rating of at most 0.5 cfm per sq ft, which is always checked before the calculator reports that a door meets the specification table. Note also that meeting the numbers in Table 2 and Table 5 is a threshold check on the NFRC values you enter, not an official product certification.
Homeowners also ask about the federal Energy Efficient Home Improvement Credit for exterior doors. On the Internal Revenue Service (IRS) credit page (read October 19, 2026), the credit limit for qualifying exterior doors was $250 per door and $500 total across all exterior doors, but that credit covered improvements made through December 31, 2025, and has expired. A current quote that still advertises the $250 or $500 federal door credit is out of date, and this calculator does not deduct any tax credit from your quote total.
Measure the egress clearances
Replacing an entry door with a narrower prehung frame, fitting sidelights into an existing opening, or adding thick stops can narrow the clear passage when the door is swung open. Before approving a quote that alters the frame width, check the clear passage dimensions against the model text of Section R311.2 (Egress Door) of the 2021 International Residential Code (IRC 2021, read on UpCodes on October 19, 2026).
In the model text of IRC 2021 R311.2, the egress door shall be side-hinged and provide a clear width of not less than 32 in measured between the face of the door and the stop with the door open at a right angle, and a clear height of not less than 78 in measured from the top of the threshold to the bottom of the stop. The model text requires this for at least one egress door per dwelling unit; whether your front door is that door is for the local authority to say. Because the thickness of the open door slab and the projection of the jamb stop sit inside the frame opening, the clear passage width is always narrower than the nominal callout width or the outside unit width.
In the default configuration, a clear width of 33 in and a clear height of 78 in pass both the 32 in width minimum and the 78 in height minimum. By contrast, in our test vector where a narrower frame or thick stop reduces the clear width to 31.75 in (with a 78 in clear height), the calculator flags that the clear width fails the 32 in minimum of IRC 2021 R311.2 by 0.25 in. Ask the installer to state the net clear opening width and height of the quoted prehung unit before ordering a smaller callout size such as 2/8, 2/6, 2/4, or 2/0. Because states and municipalities adopt their own editions and local amendments, the local authority having jurisdiction decides what applies to your house.
Total the quote line by line
Written proposals for front door replacement rarely bundle the same items into the headline figure. One bid may include the prehung door unit, lockset hardware, interior trim paint, old-door haul-away, and installation labor in a single sum, while another may price the bare door slab and jamb first and list separate add-on charges for sidelights, a transom, hardware, trim and paint, sill rot repair, rough-opening reframing, disposal, and labor.
To let you audit any written proposal without confusing an unquoted line with a free inclusion, the nine quote fields in this calculator enforce a strict separation between a blank field and a zero:
- Blank = unknown: Leaving any quote field blank tells the calculator that the contractor has not yet stated a price for that line. So long as even one line is blank, the calculator reports the sum of the known lines so far, lists every missing line by name, and withholds the per-square-foot unit rate.
- Zero (
0) = included or not needed: Entering0confirms that the line carries no separate charge on your project—either because your doorway has no sidelights, transom, rot repair, or reframing, or because the written proposal explicitly bundles that work into another priced line.
When all nine lines are filled in with dollar amounts or confirmed zeros, the quote is marked complete, and—provided your rough opening matches a fitting Therma-Tru size in both width and height—the calculator divides the complete quote total by the outside unit area in square feet:
Complete Quote Total ($) = Sum of All 9 Priced or Zero-Confirmed Lines
Price per Sq Ft of Door Unit = Complete Quote Total ÷ (Unit Width × Unit Height ÷ 144)
In our complete-ledger test vector on the default 38.25 in by 82 in rough opening—which matches the 3/0 × 6/8 unit measuring 37.5 in by 81.625 in—entering $1,800 for the door unit, $0 for sidelights, $0 for transom, $150 for lockset and hardware, $200 for trim and paint, $0 for rot repair, $0 for reframing, $50 for removal and disposal of the old door, and $650 for installation labor produces a complete quote total of $2,850 and a unit rate of $134.08 per sq ft of door unit. Notice how the lines beyond the $1,800 door unit ($150 hardware, $200 trim and paint, $50 disposal, and $650 labor) bring the complete project to $2,850. If your rough opening is 37.5 in wide and you decide to widen it by 0.75 in to fit a 3/0 door instead of accepting a 2/10 door with a 1.25 in gap, make sure the carpenter’s charge for widening the opening is entered on the Reframing the opening line rather than left blank.
What the household survey measures
| Area | Weighted median |
|---|---|
| United States | $2,800 |
| Northeast | $3,200 |
| Midwest | $2,300 |
| South | $2,300 |
| West | $3,000 |
Nationally the survey holds 2,477 sample projects; the 25th and 75th percentiles are $800 and $7,000, and 31.4% of the weighted projects were do-it-yourself.
The table above comes from our extraction of the U.S. Census Bureau’s 2023 American Housing Survey (AHS) public-use file for job type 18 (verified October 11, 2026). In the AHS questionnaire, exterior window replacements and exterior door replacements are combined inside a single self-reported project category—job type 18—and the survey does not record whether a household replaced one front door, several doors, or a houseful of windows, and its distribution pools professional and do-it-yourself projects.
Across the 2,477 national sample cases in AHS 2023 job type 18, owner-reported spending had a weighted median of $2,800, a 25th percentile of $800, and a 75th percentile of $7,000, with 31.4% (0.3143) of weighted projects done do-it-yourself. By Census region, the AHS 2023 weighted median was $3,200 in the Northeast, $2,300 in the Midwest, $2,300 in the South, and $3,000 in the West. Because those figures pool windows and doors together and include the 31.4% DIY share, they serve only as a dated household-survey category benchmark—never as a price quote for a single front door.
Front door cost questions
How much should a new front door cost installed?
No prefilled installed price is supplied by this tool: your installed cost is the sum of the nine quote lines for your specific opening (door unit, sidelights, transom, hardware, trim and paint, rot repair, reframing, disposal, and labor). In our complete test vector ($1,800 door, $150 hardware, $200 trim and paint, $50 disposal, $650 labor, and $0 on the remaining four lines), the total is $2,850 ($134.08/sq ft on a 3/0 × 6/8 unit). The 2023 AHS windows-and-doors category median of $2,800 is a combined survey benchmark, not a single-door price.
What is the average cost to have a front door replaced?
The AHS, the federal survey used here, does not isolate front doors from windows. In the U.S. Census Bureau’s 2023 American Housing Survey (job type 18, windows and doors combined, 2,477 cases, verified October 11, 2026), self-reported household project spending had a national median of $2,800 and a 25th-to-75th percentile range of $800 to $7,000, with 31.4% of projects done DIY.
What is the labor cost to remove and install exterior door and frame?
Labor and frame work are entered on three separate lines in the ledger: Removal and disposal of the old door, Reframing the opening, and Installation labor (for example, $50 disposal, $0 reframing, and $650 labor in our worked 3/0 vector). Check the rough-opening match first to see whether your opening fits a listed size directly or needs to be widened (such as widening a 37.5 in opening by 0.75 in to fit a 38.25 in 3/0 rough opening) before comparing carpenter labor quotes.
What is the labor cost to replace exterior door?
This calculator does not supply a default labor rate; enter the installation labor charge from your contractor’s written proposal on the Installation labor line. Leaving the labor line blank marks Installation labor as missing, keeps the quote incomplete and withholds the complete total and per-square-foot rate so an unquoted labor charge is never mistaken for zero.
What is the front door replacement cost per square foot?
When all nine quote lines are filled in and the rough opening matches a listed Therma-Tru size, the calculator divides your complete quote total by the matched door’s unit area (unit width × unit height ÷ 144). For a 3/0 × 6/8 unit (37.5 × 81.625 in), a $2,850 complete quote equals $134.08 per sq ft of door unit.
What is the entry door replacement cost?
An entry door is the same exterior swinging door checked by this worksheet. Enter your rough opening dimensions, the NFRC thermal label ratings, the clear opening width and height, and the nine quote lines to check fit, the ENERGY STAR Version 7.0 table values, egress clearance and total cost on one page.
How much does Home Depot charge to replace a front door?
This page publishes no retailer price figures. From any written installation quote, enter each quoted amount into the nine ledger lines—separating the prehung door unit, sidelights, transom, lockset hardware, trim and paint, rot repair, reframing, old-door disposal, and installation labor, and leaving any unstated line blank until confirmed.
How much does Lowes charge to install a new front door?
No store pricing is supplied here. From any written installation quote, enter each amount (or 0 if bundled) on the nine lines—especially trim and paint, sill rot repair, rough-opening reframing, and old-door haul-away—so you can compare the complete bottom line against independent bids.
How does this front door replacement cost calculator work?
It performs three checks from primary tables read on October 19, 2026 and a line-by-line quote total: it matches your rough opening to Therma-Tru’s 6/8 inswing single table (2/0 through 3/6), checks your NFRC U-factor, SHGC, and air leakage against ENERGY STAR Version 7.0 Tables 2 and 5, checks clear width (at least 32 in) and clear height (at least 78 in) against IRC 2021 R311.2, and it sums your nine quote lines.
How do I find the front door replacement cost near me?
The 2023 AHS table above shows regional weighted medians for combined window-and-door projects—$3,200 in the Northeast, $2,300 in the Midwest, $2,300 in the South, and $3,000 in the West—as category context. To find your actual local price, measure your rough opening and collect itemized nine-line quotes from local installers for the same door size and NFRC specification.
What is the labor cost to install interior door?
Interior passage and closet doors are outside the scope of this calculator, which applies only to exterior swinging entry doors subject to exterior rough-opening sizing, ENERGY STAR Version 7.0 thermal thresholds, and IRC 2021 R311.2 egress clearances.
Read the check with its boundaries
- One manufacturer’s inswing single sizes at 6/8 height. Outswing, taller, double and French units are not listed; other makers’ tables differ.
- The ENERGY STAR check reads the label values you enter. It does not certify a product.
- The egress check uses the model text of IRC 2021 R311.2; the code adopted where you live, and its inspector, decide.
- Exterior swinging doors only. Interior, storm and sliding doors are outside this worksheet.
- No door price, labor rate or sidelight price is supplied.