Double Hung Window Sizes: A Complete Guide for Homeowners

Choosing the right double hung window sizes is one of the most important decisions in any window replacement or new-construction project. Order a unit that is even a half inch off, and you are looking at drywall repair, trim rework, or worse, a window that will not fit at all. Because double hung windows, the classic style with two vertically sliding sashes, are the most common residential window in America, they come in a wide range of standardized dimensions that make planning straightforward once you understand how manufacturers label them.

Part of our Windows & Doors guide — explore the full guide →

This guide walks through standard sizes, how to read a window’s size code, the difference between the unit and the rough opening, how to measure your existing windows, and what different sizes cost.

How Double Hung Windows Are Sized

Window manufacturers list two important numbers: the rough opening and the actual window unit size. The rough opening is the framed hole in your wall, slightly larger than the window itself so the unit can be shimmed square and level. The unit size is the physical dimension of the window frame. Typically the actual window is about 1/2 inch smaller than the rough opening in both width and height, leaving room for shimming and insulation.

Windows are always listed width first, then height. So a “3050” window is 3 feet 0 inches wide by 5 feet 0 inches tall. This four-digit shorthand, called the window’s call size, is standard across most brands. The first two digits are the width in feet and inches, and the last two are the height. A 2846 window is 2 feet 8 inches wide by 4 feet 6 inches tall.

Standard Double Hung Window Widths

Common stock widths for double hung windows range from about 24 inches to 48 inches. The most frequently stocked widths include:

• 24 inches (2’0″) — narrow windows for bathrooms, stairwells, and tight spaces.
• 28 inches (2’4″) — a common bedroom width.
• 32 inches (2’8″) — one of the most popular general-purpose widths.
• 36 inches (3’0″) — a standard living-room and bedroom width.
• 40 inches (3’4″) — a wider option for larger rooms.

Widths generally increase in 4-inch increments, giving you flexibility to match nearly any wall opening.

Standard Double Hung Window Heights

Heights typically run from around 36 inches up to 72 inches. Common stock heights include:

• 36 inches (3’0″) — short windows for above kitchen counters or in basements.
• 48 inches (4’0″) — a versatile mid-height window.
• 54 inches (4’6″) — very common in bedrooms and living rooms.
• 60 inches (5’0″) — a tall window that maximizes daylight.
• 72 inches (6’0″) — full-height windows, often near floors in older homes.

The Most Common Double Hung Sizes

While there are dozens of combinations, a handful of sizes dominate American homes. A 3050 (36″ x 60″) window is arguably the single most common double hung size, appearing constantly in living rooms and bedrooms. Other everyday combinations include 2840 (32″ x 48″), 2852 (32″ x 62″), 3040 (36″ x 48″), and 2440 (28″ x 48″). If your home was built after the 1970s, chances are good your windows match one of these standard call sizes, which makes ordering replacements far easier and cheaper than custom units.

Custom vs. Standard Sizes

Not every home fits stock dimensions, especially houses built before World War II, additions, or homes with unusual architecture. Custom windows can be manufactured to nearly any size, usually in 1/8-inch increments. The trade-off is cost and lead time. A standard-size vinyl double hung might ship in a week or two, while a custom unit can take four to eight weeks and cost 25 to 50 percent more. If your opening is close to a standard size, many installers will build out or trim the rough opening to accept a stock window rather than order custom, saving you money.

How to Measure for Replacement Windows

Accurate measurement is critical. For a replacement (insert) window that fits into your existing frame, follow these steps:

1. Measure the width at three points: top, middle, and bottom of the opening, from jamb to jamb. Use the smallest measurement.
2. Measure the height at three points: left, center, and right, from the sill to the head jamb. Again, use the smallest.
3. Check the diagonals to confirm the opening is square. If the two diagonal measurements differ by more than 1/4 inch, the frame is out of square and you may need shimming.
4. Measure the depth to ensure the jamb is deep enough for the new unit, typically at least 3-1/4 inches for a standard replacement.

Always subtract about 1/4 inch from your smallest width and height measurements to give the installer room to fit and shim the unit. When in doubt, have a professional field-measure before ordering; a mistake here is expensive.

Rough Opening Guidelines for New Construction

If you are building or enlarging an opening, the rough opening should be roughly 1/2 to 3/4 inch larger than the window’s unit dimension in both directions. For a 36″ x 60″ window, frame a rough opening of about 36-1/2″ x 60-1/2″. Always confirm the exact rough opening on the manufacturer’s spec sheet, as it varies slightly by brand and frame material. Getting the rough opening right lets you plumb, level, and square the window without stress on the frame.

How Size Affects Cost

Larger windows use more material and glass, so price scales with size. Here are typical installed-price ranges for vinyl double hung windows:

• Small (24″ x 36″) — roughly $300 to $500 installed.
• Standard (36″ x 60″) — roughly $450 to $800 installed.
• Large (40″ x 72″) — roughly $600 to $1,100 installed.
• Custom sizes — add 25 to 50 percent over comparable stock units.

Frame material also matters: wood and fiberglass cost more than vinyl, and premium glass packages with low-E coatings and argon fill add to the total. Labor typically runs $100 to $300 per window depending on your region and whether the opening needs modification.

Egress and Building Code Considerations

If a double hung window serves a bedroom or basement as an emergency escape, it must meet egress code. The International Residential Code requires a minimum net clear opening of 5.7 square feet (5.0 square feet at grade level), a minimum opening height of 24 inches, a minimum opening width of 20 inches, and a sill no higher than 44 inches off the floor. Because a double hung only opens to half its height, you often need a larger overall window to meet egress. Always verify egress requirements before finalizing bedroom window sizes, since failing inspection means reordering.

Frame Material and How It Interacts with Size

The frame material you choose interacts with sizing in ways worth understanding. Vinyl frames are the most forgiving and affordable across all standard sizes, but very large vinyl double hung units can flex, so manufacturers cap the maximum size for structural reasons. Wood frames offer classic looks and can be built to larger custom dimensions but require more maintenance. Fiberglass and composite frames are the strongest, holding large glass spans with thin sightlines, which lets you maximize glass area even in big openings. If you are ordering a very tall or wide double hung, ask the manufacturer for the maximum available size in each material, since not every size is offered in every frame line. Larger units also weigh significantly more, which matters for a window you will raise and lower daily, so balance-assist hardware quality becomes more important as size increases.

Matching New Windows to Older Homes

Homes built before the 1950s often have windows that do not match any modern call size, sometimes because of settling, sometimes because the originals were job-built. In these cases, measuring accurately is even more critical, and you will likely be choosing between a custom-sized unit or building out the opening to accept the nearest standard size. Many older homes also have taller, narrower proportions than modern stock, so a custom order may be the only way to preserve the home’s original character without awkward filler panels. Weigh the higher cost of custom against the appearance compromise of forcing a standard size into a non-standard opening.

Getting the Right Fit

The key to a smooth window project is understanding that the call size, the rough opening, and the actual unit size are three related but distinct numbers. Measure your existing openings carefully at multiple points, match to the nearest standard size when possible to save money, and confirm the manufacturer’s spec sheet before ordering. Whether you are replacing a single leaky bedroom window or re-outfitting an entire home, knowing the standard double hung window sizes puts you in control of both the budget and the outcome.