Picture Window Replacement: Options, Cost and How It Works

A picture window is a large pane of glass in a frame that does not open, so it gives an unbroken view and lets in the most light for its size. Replacing one costs about $300 to $1,300 installed by national averages, and it is also your chance to make the new window open. On an old one, what fails is the glass seal or the frame, since nothing slides, cranks or hinges.

We fit ProVia picture windows across the St. Louis area, as fixed units and as the center of a group with opening windows on each side.

If you already know what you want, our picture window installation page lists the ProVia lines we install and the finishes.

When Does a Picture Window Need Replacing?

Replace it when fog or water shows between the panes, the glass is cracked, or the frame around it has gone soft. Each one means water or air is getting past something that is supposed to be sealed. For the wider checklist on aging windows, see how to tell when windows need replacing.

Fog, haze or droplets between the two panes. The seal on the insulated glass has failed. It will not clear up, and the glass no longer insulates as it should.
A crack or a chip that has started to run. A crack in one pane of an insulated unit lets the gas out and the damp in.
Soft, dark or flaking wood at the sill or jamb. Water has been reaching the frame for some time.
A cold draft or a wet stain at the edges. The sealant or the flashing around the frame has given out.
A room that bakes in the afternoon or freezes by the glass. An older unit without a low-e coating passes far more heat than a new one.

Many mid-century ranch houses in the St. Louis area have one big window at the front of the living room, and it is often the original unit, now decades old.

What Can Go in the Opening?

A living room corner with one tall double hung window on the left and a group of three double hung windows on the right, each with a grid in the top sash

Either another fixed window or one that opens. Nothing says the new unit has to match the old one.

The same fixed window, new glass and frame. The simplest swap, and the best view.
A fixed center with an opening window on each side. The center gives you the view and the sides give you air. The sides are usually double hung or casement units.
One large window that opens. A casement or a slider sized to the opening. You lose the unbroken glass and gain a breeze.

What decides it is the size of the opening. A unit of the same size drops into the space that is already framed. A different size means the framing changes, and if the opening gets wider, a new header goes over it. That is a carpentry job as well as a window job, and it belongs in the price from the start.

How Do You Choose a Replacement?

Choose the frame first, then the glass, then the grid pattern. Each one changes the price and how the window looks and lasts.

Frame. Vinyl needs the least care. Fiberglass is stiffer, so the frame can be slimmer. Wood gives the warmest look inside but has to be kept sealed and painted. ProVia builds this window in 4 lines. Endure is vinyl. Aeris pairs a vinyl exterior with a real wood interior. Aspect is built around energy savings, and EcoLite is the budget line.
Glass. A low-e coating and a gas fill between the panes are the two upgrades worth having, and the unit is either double or triple pane. A wide pane facing west or south in a St. Louis summer is where that coating earns its cost.
Grids. A fixed window with no grid gives the cleanest view. Grids set between the panes cost more than none and break up the view, but they match the other windows on a traditional house.

Look for the rating label on the glass. It lists the U-factor, which is how much heat leaves through the window. The other number is the solar heat gain coefficient, a rating of how strongly the glass lets the sun warm the room. On a big pane both matter: the first decides how much heat leaks out in winter, and the second decides how much sun heat pours in during summer.

What Does Replacement Cost?

National cost guides put it at about $300 to $1,300 per window, installed, and up to about $3,200 for the largest sizes. That range comes from HomeGuide’s cost guide, dated September 2025. It is a national average, not our price list.

Four things move the number most:

Size. The same guide lists common sizes from 24 by 36 inches to 96 by 96 inches, and the price climbs with every square foot of glass.
Glass. Triple pane and special coatings cost more than double pane.
Frame. Vinyl costs least. Fiberglass and wood cost more.
Reach. A window on a second story, or blocked by a counter or a built-in, takes longer to get in and out.

A fixed window usually costs less than an opening window of the same size, because it has no moving parts. The cost that surprises people is a rotted sill found after the old unit comes out. It has to be dealt with before the new one goes in, and it cannot be priced from a photo.

How Does the Swap Work?

An installer in a blue cap lifting a new window unit up into a finished opening

Someone measures the opening, orders a unit built to that size, takes the old one out, and sets the new one level in the same space. The order matters, because the unit is made to the numbers and cannot be cut down on site.

Measure. Width in 3 places, top, middle and bottom, and height in 3 places, left, center and right. The smallest of each is the one that counts.
Check the frame. Look at the sill and jamb for rot and test whether the opening is square.
Order. The unit is built to those numbers.
Remove. The old glass or the whole old unit comes out, depending on the method below.
Set and level. The new unit goes in, gets shimmed until it is plumb, and is fastened through the frame.
Seal. Foam fills the gap around the frame, sealant goes on the outside, and the inside trim goes back.

There are 2 ways to do steps 4 and 5. An insert goes inside the frame that is already there, which is quicker and keeps the trim. A full-frame swap removes the frame too, down to the rough opening, which is the answer when the frame is rotted or the size is changing. A big pane is heavy, so it takes more than one person and suction handles, and a dropped unit is a total loss.

Does a Big or Low Window Need Safety Glass?

Sometimes. The model residential code treats a pane as a hazardous location, which means tempered or laminated safety glass, when all 4 of these are true.

The pane is larger than 9 square feet.
The bottom edge is less than 18 inches above the floor.
The top edge is more than 36 inches above the floor.
A walking surface is within 36 inches of the glass.

The four conditions above come from section R308.4.3 of the 2018 International Residential Code. A tall, wide window that starts near the floor of a living room can meet all four. Your city or county building department decides which edition of the code applies where you live, so ask which glass the new unit has.

Do You Need a Permit to Replace It in St. Louis?

Only inside a City of St. Louis historic district. Outside one, that city office does not look at window work.

According to the city’s review FAQ, window replacement falls under a district’s design standards, and each district has a different set. A front window is the one most likely to be seen from the street, so it is the one a reviewer looks at first. The office’s main line is 314-657-3865. Suburbs and the county follow their own building rules, so ask your city hall.

Where Do They Fall Short?

A fixed window cannot give you air. If the room already runs hot and stuffy, that is the reason to put opening windows beside it.

Sun is the other cost. A large pane on the west side heats the room in summer and fades floors and furniture. A low solar heat gain number helps, and so do shades. Cleaning is awkward too, because the outside of a fixed window has to be reached from outside, and on a second floor that means a ladder or a service.

What We Do Not Do

Fixing the window you have. Re-sealing a fogged unit is repair work, and we only install new windows. A page like this is not for you if a re-seal is all you need, and we are the wrong company to call.
Commercial glass. Storefront and office glass is a different product. Our work is residential.

Common Questions

National guides put it at about $300 to $1,300 installed for most windows, and up to about $3,200 for the largest sizes. Size, glass, frame and how hard the window is to reach set the price. A price list would mislead you, because the sill and the opening change the answer.

Yes. Two common choices are a large casement or slider in the same opening, or a fixed center with an opening window on each side. A different size from the old window needs new framing and sometimes a new header, so it costs more than a straight swap.

Measure the width in 3 places and the height in 3 places, and use the smallest of each. Then check that the opening is square. The estimate visit includes measuring every opening, because a unit is built to those numbers and cannot be trimmed on site.

Cost guides list common sizes from 24 by 36 inches up to 96 by 96 inches, and custom sizes are made too. A larger window costs more and is harder to get into the opening.

No. Large fixed glass is still used in new houses and remodels. What dates one is the frame color, the grid pattern and old glass, not the idea. A plain frame with no grid reads as current.

Often, yes. A fixed window has no sash seal to leak, so with the same glass it usually holds air better than one that opens. The glass matters more than the style, so compare the numbers on the label.

Only in a hazardous location under the code. A pane over 9 square feet, less than 18 inches above the floor, with its top edge more than 36 inches up and a walking surface within 36 inches, qualifies under the model residential code. Ask your building department which edition applies.

Sometimes a failed sealed glass unit can be swapped in a frame that is still sound. That is repair work, and we do not do it. We install complete new windows.

Getting a Price

A real price needs the size, the frame and the glass, plus a look at the sill. Book an on-site visit and we will measure each opening while we are there. The number to call is 314-277-5952, or use the estimate page.

ProVia lists dealers on its dealer locator, and we are on it as a Platinum dealer. The 10 year guarantee covers our workmanship, and finished work is in our photo gallery.