Start with the number
What Denver homeowners actually pay
Window salespeople avoid this question for forty minutes. Here is the answer first.
| Frame material | Per window installed | Expected service life here | Best fit |
|---|---|---|---|
| Vinyl | $575 to $950 | 15 to 25 years | Most homes. Best cost per year unless the openings are very large. |
| Fiberglass | $850 to $1,450 | 25 to 40 years | Large openings and west-facing walls. Expands at nearly the same rate as glass, so seals last longer through Denver's swings. |
| Wood or clad-wood | $1,000 to $1,900 | 30 years plus with maintenance | Historic districts, and any home where the interior sightline matters. |
| Aluminium | $500 to $900 | 20 to 30 years | Rarely right for a Colorado home. Metal conducts cold straight through unless the frame is thermally broken. |
Full-house jobs get discounted. Expect roughly 6 percent off per-window pricing at five or more openings, and around 12 percent at ten or more. Bay, bow, arched and custom shapes run well above these bands.
The three questions that decide your quote
1. Insert, or full-frame?
An insert replacement sets a new window inside your existing frame. The exterior is untouched, the job takes under an hour per opening, and it is the cheaper route. The cost is glass area: you lose roughly one to two inches in each direction, which is noticeable on a small bathroom window and invisible on a large picture window.
A full-frame replacement removes everything down to the rough opening. You keep your original glass size, the installer can see and correct the flashing, and rot gets fixed rather than buried. It costs more and it takes longer. If a contractor pushes insert replacement on a window with a soft or stained sill, get a second opinion. You are being sold a cover-up.
2. Is the seal failed, or is the whole window failed?
Permanent fog between the panes means the insulated glass unit has lost its seal. That is a glass problem, not always a window problem. If the frame and hardware are sound, replacing the glass unit alone can cost a third of a full replacement. See Denver window repair before you commit to a whole-house project. Some sales processes are designed to make sure you never ask.
3. Was it hail?
The Front Range is one of the most hail-exposed corridors in the country. If a storm broke glass, dented frames, or tore screens and cladding, this may be an insurance claim rather than a home improvement project. Photograph everything, keep the date, and call your carrier before you order anything. A contractor who offers to make your deductible disappear is proposing insurance fraud, and it is your name on the claim.
Why Denver windows fail faster than the brochure says
- Altitude. At 5,280 feet, a unit sealed at sea level is permanently bowed outward by internal pressure. That stress fatigues the edge seal. Units built for this market use a capillary breather tube or an altitude-adjusted gas fill. Ask which.
- Ultraviolet load. Thin air filters less UV. Vinyl chalks, gaskets harden, and exterior finishes fade faster here than at sea level.
- Daily temperature swing. Thirty to forty degree swings between afternoon and dawn are ordinary in a Denver spring. Every swing works the frame against the glass. Materials that expand at different rates lose that fight first.
- Hail. Direct hits crack glass. Near misses dent cladding and shred screens, and both let water into places it should not reach.
- Dry air. Low humidity shrinks wood frames and opens joints that would stay tight in a wetter climate.
What a real quote looks like
Insist on these lines, itemised. A single lump sum hides everything worth negotiating.
- Unit count, and the exact model and series per opening
- U-factor and Solar Heat Gain Coefficient from the NFRC label, not marketing numbers
- Insert or full-frame, stated per opening
- Low-emissivity coating type and gas fill
- Interior trim, exterior capping, and who paints
- Disposal and haul-away
- Glass warranty and labour warranty, as two separate terms
- Permit responsibility and fee
- Lead time, and what happens if it slips
One negotiating fact. Replacement windows are one of the most expensive lead categories in all of home services. Marketing benchmarks put the cost of a single Google search lead for replacement windows near $200, and a closed customer near $375 to $600. That money is inside your quote. It is why the same job can be quoted at $8,000 by one company and $16,000 by another, and it is why three quotes are worth more than any discount a salesperson offers to protect a single visit.
Common questions
How much does window replacement cost in Denver?
Most Denver metro homeowners pay between roughly $575 and $950 per window installed for vinyl, $850 to $1,450 for fiberglass, and $1,000 to $1,900 for wood or wood-clad. A ten-window house therefore lands somewhere between about $5,000 and $19,000. Contractors discount full-house jobs, so your per-window price drops as the count rises. Treat these as ranges for budgeting, not quotes.
Is it worth replacing windows just to save energy?
Rarely on energy savings alone. Replacement windows typically trim 7 to 15 percent off a heating and cooling bill, which on a Denver home is often a few hundred dollars a year against a five-figure project. The honest reasons to replace are comfort, noise, failed seals, rot, windows that will not open, and resale appearance. Anybody selling you windows purely on the payback maths is selling, not advising.
Insert or full-frame replacement?
Insert, also called a pocket replacement, keeps the existing frame and sets a new unit inside it. Faster, cheaper, no exterior work, and you lose one to two inches of glass on each dimension. Full-frame strips everything back to the rough opening. More expensive, keeps the original glass area, and it is the only right answer when the frame is rotten or the sill is holding water.
How long do replacement windows last in Colorado?
Fifteen to twenty-five years for a mid-range vinyl unit on the Front Range, which is shorter than the manufacturer's brochure suggests. Intense high-altitude ultraviolet light, daily temperature swings of thirty degrees or more, and hail all age a window faster here than in a mild coastal climate. Fiberglass and clad-wood generally outlast vinyl.
What are the signs a window seal has failed?
Permanent haze or fog between the panes, a white mineral film on the inside of the glass, or visible condensation that no amount of wiping reaches. That is a failed insulated glass unit. Once the seal is gone the insulating gas is gone with it, and the window performs roughly like single glazing.
Are there rebates for replacement windows in 2026?
The federal Energy Efficient Home Improvement Credit, Section 25C, was terminated for property placed in service after 31 December 2025 by the One Big Beautiful Bill Act. So no federal window credit applies to a 2026 install. Utility and state programmes are separate and change often. Check Xcel Energy's current residential rebate list and the Colorado Energy Office before you assume anything, and get any rebate promise in writing from the contractor.
Where we work
Denver, Aurora, Lakewood, Arvada, Westminster. See also installation for new openings and repair for single failed units.
Three quotes beat one discount
The spread between the high and low bid on a Denver window job is routinely 40 percent for identical work. One request gets you the comparison.