Sunrooms
Sunroom Windows: Vinyl vs Glass, and Which Is Right for You
October 20, 2026
Vinyl sunroom windows, like the WeatherMaster 4-track windows on the Sunspace Model 200, are right for you if you want a room that opens up to 75 percent for fresh air at a lower price, while glass windows are right for you if you want clearer views and a more traditional window feel, with single-glazed glass on the Model 300 for three-season use and insulated Low-E argon glass on the Model 400 for year-round use. Vinyl is not glass, and glass is not vinyl. Each does some things better. This guide compares them honestly on ventilation, clarity, weather and seasons, care, and price, so you can pick the one that fits how you will use the room.
We are an authorized Sunspace dealer and the builder, and we install all three of these window types. The Model 200 WeatherMaster is our most popular room, but it is not the right choice for everyone.
The three window types at a glance
| Model 200 WeatherMaster | Model 300 | Model 400 | |
|---|---|---|---|
| Window material | Vinyl glazing | Single-glazed glass | Low-E argon insulated glass |
| Window style | Vertical 4-track | Double-roller, vents from both sides | Insulated windows in thermal walls |
| Ventilation | Opens up to 75 percent | Vents from both sides | Operable windows in an insulated room |
| Room type | Three-season | Three-season | Four-season |
| Frame | Sunspace room system | Extruded aluminum | Thermal breaks in the frame |
WeatherMaster vinyl windows (Model 200)
The Model 200 WeatherMaster uses vertical 4-track vinyl windows. The panels slide so you can open the room up to 75 percent for ventilation, which is far more open area than a typical window. Close them and they seal tight against weather and bugs. Screens keep insects out when the panels are open.
What vinyl does well:
- Ventilation. Up to 75 percent open makes the room feel close to a screen porch on a nice day, then closes up when the weather turns.
- Flexibility. You can open just the top, just the bottom, or most of the panel, depending on wind and temperature.
- Price. The Model 200 is typically the lowest-cost enclosed sunroom in the Sunspace line.
- Weight. Vinyl panels are lighter than glass, which can matter when the room sits on an existing deck.
What to be honest about:
- Clarity. Vinyl is clear, but it is not glass. Views through it are not as crisp, especially at an angle or in bright light.
- Care. Vinyl scratches more easily than glass and needs gentle cleaning. More on that below.
- Winter. A WeatherMaster room is a three-season room. It is not comfortable in deep winter without heat, and it is not built to hold heat like an insulated room.
We compare WeatherMaster with another popular vinyl panel system in Sunspace WeatherMaster vs EZE-Breeze, and you can see the room itself on our WeatherMaster sunrooms page.
Single-glazed glass windows (Model 300)
The Model 300 is a bright glass three-season room on extruded aluminum. It uses single-glazed glass in double-roller windows that vent from both sides.
What glass does well:
- Clarity. Glass gives you a cleaner, sharper view of the yard. If the view is the main reason you want a sunroom, this is the biggest difference you will notice.
- Feel. Glass windows feel more like a traditional room and less like an enclosed porch.
- Scratch resistance. Glass holds up better to everyday cleaning and contact than vinyl.
- Breakage coverage. Sunspace covers window and door glass breakage for life under its limited lifetime warranty.
What to be honest about:
- Ventilation. Double-roller windows vent from both sides, which gives good cross-breeze, but the room does not open up the way a 4-track vinyl room does.
- Insulation. Single-glazed glass is not insulated glass. The Model 300 is still a three-season room and is not comfortable in deep winter without heat.
- Price. At the same size, a Model 300 is usually a few thousand dollars more than a Model 200.
Our three-season sunrooms page covers both the Model 200 and the Model 300.
Low-E argon insulated glass (Model 400)
The Model 400 is the insulated four-season room. It combines thermal walls, Low-E argon glass, and thermal breaks in the frame, with an optional insulated floor. The insulated glass is a big part of what makes the room usable all year.
- Year-round comfort. Insulated glass, together with the insulated walls and frame, holds heat in winter and helps limit heat gain in summer. The room runs on its own heating and cooling, such as a ductless mini-split.
- Clarity. You get the clear view of glass with the comfort of an insulated room.
- Warranty. Insulating glass units carry 15-year coverage against seal failure and fogging, and glass breakage is covered for life.
- Price. A Model 400 costs roughly $35,000 to $40,000 more than a Model 200 of the same size, because you are buying an insulated room, not just different windows.
Learn more on our insulated four-season sunrooms page and in our four-season room guide.
Ventilation compared
If fresh air is your top priority, vinyl wins. WeatherMaster panels open up to 75 percent, so on a mild spring evening the room feels almost open. The Model 300's double-roller glass windows vent from both sides for good cross-ventilation, but the open area is smaller. The Model 400 has operable windows, but it is designed as an insulated room that runs on its own heating and cooling most of the year.
Maryland summers are humid, and good airflow makes a big difference in how a three-season room feels in June and September. Our article on how to keep a sunroom cool in summer covers ventilation, shading, and roof choices.
Clarity and views compared
Glass is clearer than vinyl. That is simply true. Both Model 300 and Model 400 glass give a crisper view than WeatherMaster vinyl. Many homeowners are happy with vinyl because the room is used mainly with the panels open, which puts only a screen between them and the yard. If you expect the windows to be closed most of the time and you care about the view, glass is worth the extra cost.
Weather and seasons compared
- Spring and fall: all three work well. Vinyl and single-glazed glass let you close out wind, rain, and pollen on cool days and open up on warm ones.
- Summer: vinyl's 75 percent ventilation is a real advantage. A Model 400 with its own cooling handles the hottest days best.
- Winter: only the Model 400 is built for it. A Model 200 or Model 300 is a three-season room and is not comfortable in deep winter without heat. See can you heat a three-season room for an honest look at what a heater can and cannot do.
Care and cleaning
This is where vinyl needs more attention. Sunspace's 10-year coverage on vinyl glazed windows against fading and cracking requires following its cleaning instructions. Vinyl must be cleaned gently: no harsh cleaners, no detergents, and no bleach. Use a soft cloth and mild approach, and avoid anything abrasive that can scratch the surface.
Glass is more forgiving to clean, and glass breakage is covered for life. On a Model 400, the insulating glass units carry 15-year coverage for seal failure or fogging.
Price compared
Here are typical ranges for complete sunroom additions with roof and walls, from our pricing calculator:
| Size | Model 200 (vinyl) | Model 300 (single-glazed glass) | Model 400 (insulated glass) |
|---|---|---|---|
| 12x12 (144 sf) | $38,000 to $50,000 | $42,000 to $55,000 | $75,000 to $90,000 |
| 12x14 (168 sf) | $40,000 to $55,000 | $45,000 to $60,000 | $80,000 to $95,000 |
| 14x16 (224 sf) | $52,000 to $65,000 | $55,000 to $68,000 | $90,000 to $105,000 |
| 16x20 (320 sf) | $65,000 to $80,000 | $68,000 to $85,000 | $100,000 to $120,000 |
At the same size, the Model 300 is usually a few thousand dollars more than the Model 200. The Model 400 is a bigger step, roughly $35,000 to $40,000 more than a Model 200 of the same size.
If you already have a covered porch, a walls-under system can enclose it under the existing roof. Typical ranges run $22,000 to $55,000 for WeatherMaster 4-track, $28,000 to $62,000 for WeatherMaster Plus bi-fold, and $32,000 to $68,000 for a full glass system, for sizes from 12x12 to 16x20. WeatherMaster 4-track comes in 4 tint options, WeatherMaster Plus folds for unobstructed views, and the full glass system gives a traditional look and clarity. See our walls-under systems page for details.
These are typical ranges. Try the sunroom pricing calculator for your size, and know that the final number comes in our written proposal.
Can you start with one and change later?
Sometimes. A Model 100 aluminum screen room can be upgraded later with vinyl windows, so some homeowners start with a screen room and add WeatherMaster panels when the budget allows. Moving from a three-season room to an insulated four-season room is a different matter, because the Model 400 uses thermal walls, thermal breaks in the frame, and insulated glass throughout. That is a different room, not a window swap. If you think you will want year-round use, it is usually better to plan for it from the start. We are glad to talk through how you expect to use the room over the next several years before you choose.
Which is right for you?
- Choose WeatherMaster vinyl (Model 200) if fresh air and a lower price matter most, and you will use the room spring through fall.
- Choose single-glazed glass (Model 300) if you want clearer views and a more traditional window feel in a three-season room, and the extra few thousand dollars is worth it to you.
- Choose insulated glass (Model 400) if you want to use the room all year with its own heating and cooling.
Let's look at your space
- A free phone conversation. Tell us how you want to use the room. We will give you a price bracket on that first call.
- A one-hour on-site visit. We bring samples so you can see vinyl and glass side by side, along with colors.
- A to-the-penny written proposal. You get a final number for the full scope.
Call 443-616-1459 or start a conversation. Let's talk about your outdoor space.
Frequently asked questions
Are vinyl sunroom windows as clear as glass?
No. Vinyl is clear, but glass gives a sharper view, especially at an angle or in bright light. Many homeowners are happy with vinyl because they use the room with the panels open much of the time.
How much do WeatherMaster windows open?
WeatherMaster vertical 4-track vinyl windows open up to 75 percent for ventilation and close tight against weather and bugs.
How much more does a glass sunroom cost than a vinyl one?
At the same size, a Model 300 glass three-season room is usually a few thousand dollars more than a Model 200 WeatherMaster. For example, a 12x12 Model 200 typically runs $38,000 to $50,000 and a 12x12 Model 300 typically runs $42,000 to $55,000. A Model 400 with insulated glass costs roughly $35,000 to $40,000 more than a Model 200 of the same size.
Can I use a vinyl or single-glazed glass sunroom in winter?
The Model 200 and Model 300 are three-season rooms and are not comfortable in deep winter without heat. For year-round use, the Model 400 with Low-E argon insulated glass, thermal walls, and thermal breaks in the frame is the room built for it.
How do I clean vinyl sunroom windows?
Clean vinyl gently and follow Sunspace's cleaning instructions. Do not use harsh cleaners, detergents, or bleach. Following those instructions is required for the 10-year coverage on vinyl glazed windows.
