A 4×4 window — 4 feet wide by 4 feet high, also written as a 48×48 or 4040 window, as well as 4 over 4 windows, — is one of the most balanced and versatile window sizes on the market. It offers 16 square feet of glass: large enough to flood a room with natural light, compact enough to fit bedrooms, kitchens, offices, and commercial projects alike.
“4×4” refers to the nominal size: 48 inches × 48 inches (about 1.49 m² of glass area). It is a standard call size across most product lines, but the actual unit is usually 1/4″ to 1/2″ smaller than the rough opening to allow for shimming and insulation. When requesting quotes, always confirm whether the supplier’s dimensions refer to the unit size, the frame size, or the rough opening — this single detail prevents the most common ordering mistake.
Because 4×4 is a common standard size, it is available in nearly every operating style and frame material, and it is more cost-effective than odd custom dimensions.
Nominal size (4ft × 4ft)
Glass area per unit
Metric glass area
Lower cost than custom sizes
Five operating styles cover every project — from budget-friendly rentals to high-end villas and hotels.
The most popular choice for this size. Space-efficient, easy to operate, and ideal for bedrooms and commercial buildings. Available in two-track or three-track configurations with optional security grills and screens.
Side-hinged or top-hinged designs that open outward for maximum ventilation and the tightest seal when closed. Casements are preferred where energy efficiency and sound insulation matter most.
The classic choice for North American and traditional architecture. Both sashes slide vertically in double-hung models, allowing flexible top or bottom ventilation and easy cleaning.
Non-opening units that maximize daylight and unobstructed views at the lowest cost per square foot. Often combined with operable windows in the same opening.
A European-style option offering two opening modes — tilt for secure ventilation, turn for full opening — increasingly popular in high-end residential and hotel projects.
Send us your opening sizes and photos — our engineers recommend the best configuration within 24 hours, free of charge.
Standard builds use double-glazed tempered glass; upgrades include triple glazing, Low-E coatings, laminated safety glass, and argon gas fills for lower U-values. For hot climates, prioritize Low-E and SHGC ratings; for cold climates, prioritize U-factor and thermal break frames.
As a custom window factory serving global projects, we hear the same pain points from contractors, developers, and distributors every week. Here is how we address each one.
We manufacture to your drawings, not to a catalog. Send us your measurements or architectural drawings and our engineers return a production drawing within 24 hours for confirmation — covering custom dimensions, grid patterns, colors, and hardware, with zero tooling surcharges on most profiles.
We support flexible order quantities. Standard configurations start from small trial orders, and we provide free samples so you can verify profiles, glass, and finish quality before committing to volume.
Every unit passes an 8-step QC process — cutting, corner assembly, sealing, glazing, hardware fitting, water and air-tightness testing, and final inspection. Our products carry CE, AAMA, SGS, ISO, and Energy Star certifications, and we share weekly photo and video production updates so you see your order being built in real time.
We use export-grade packaging (bubble film + EPE + wooden crates) tested for long sea freight, and ship to 120+ countries with a typical lead time of 4–5 weeks for standard builds. Multiple freight options — FOB, CIF, or door-to-door — are quoted upfront with no hidden costs.
Hardware and moving parts carry a 5-year warranty, and insulated glass units are guaranteed against seal failure for 5 years. We provide installation videos, detailed shop drawings, and remote technical support for your installers — and replacement parts ship fast when needed.
See exactly how your windows are made — from raw profile to packed crate.
CE CertifiedAAMASGSFactory DirectlyEnergy Star5-Year Warranty120+ Countries Shipped
Every project is different — that’s exactly why we built a six-step custom process that takes you from a simple measurement to fully installed windows with zero guesswork.
Start with whatever you have: opening dimensions, a few job-site photos, and the window types you’re considering. No professional drawings? Photos with simple measurements are enough to begin.
Architectural drawings or floor plans with dimensions let our engineers understand your project in full — opening schedules, wall thicknesses, facade requirements, and climate conditions. PDF, DWG, or even a hand sketch all work.
Based on your drawings, sizes, and quantities, we prepare professional draft window drawings with a detailed quotation — typically within 24 hours. Revisions are free until every detail is right.
Before production, we verify every dimension. Export customers re-measure and send confirmed data for our review; for domestic projects, our technicians measure on-site. That’s why our installation fit rate stays near 100%.
Once you approve the drawings and quotation, we confirm the order and schedule production immediately — completed within 35–40 days, with weekly photo and video updates from the line.
Windows are crated in export-grade wooden cases and shipped worldwide — sea freight standard, with FOB / CIF / door-to-door terms. Domestic projects get on-site delivery and installation. 5-year warranty support starts on arrival.
Whether you need ten windows for a villa or ten thousand for a commercial development, factory-direct sourcing cuts out intermediaries and typically saves 30% or more versus local suppliers. Send us your project details today and receive a detailed quotation within 24 hours — including material options, glass specifications, and landed cost estimates for your market.
You can get a price or send us any questions to get any information you would like to know, and we will reply to you as soon as possible.