Frequently Asked Questions (FAQs)

Product-Related Questions

What are your windows made of?

The Frame:

Our window and door frames are made up of 100% virgin vinyl (PVC). The material’s resilience is bolstered by SunShield® technology, a premium high-performance vinyl compound which contributes to industry-leading weather resistance, impact resistance, and color retention­­­.

Our custom-designed profile contains over five pounds more PVC than frames manufactured by most of our competitors, resulting in increased structural integrity.

Thermally Efficient Glass Package:

The glass package we use varies by product line. All our products come standard with:

  • Double-strength insulated glass unit
  • Low-E glass
  • Low-conductance spacer
  • Argon gas fill

To learn more about what glass package your products have visit: Standard Glass Package

How do I tilt-in my Viwinco double-hung window?

S-Series, Cambridge, and OceanView Impact Hung Windows

Tilting your window is really easy!  S-Series, Cambridge, and OceanView double- and single-hung products come standard with Tilt-n-Lock Hardware. To learn more about how to operate your Tilt-n-Lock hardware visit: Tilt-n-Lock Hardware  or watch the video below.

Edgemont Double-Hungs

Edgemont windows come with a Cam-style lock and tilt latches. In order to tilt-it follow these steps:

  1. Unlock your window
  2. Lift the bottom sash about an inch
  3. Pull in on the locking tabs located on the top left and right corners of the sash, then pull the top of the sash in

For the top sash:

Pull the sash down enough to pull in the tabs located on the top left and right corners of the sash, then pull the top of the sash in

Are grids color matched to the window for interior and exterior colors?

Yes, the side of our Grids and SDLs facing the exterior of the window will be color-matched to the exterior color, and the interior side of the grids/SDLs will be white.

To learn more about Grids/SDLs, please follow this link: Grids & SDLs

What’s the difference between rough opening and make size?

Rough Opening is the structurally-framed opening in the wall that will receive the window. For New Construction applications the actual unit will measure 1/2 inch less in width and height. For Replacement applications, the actual unit will measure 1/4 inch less in width and height.

Make size is the tip to tip measurement of the window frame (the nail fin is not part of the frame).

What side of a window or door is the glazing bead on?

The glazing bead is located on the outside of the house for all products except for non-operable windows.

Glazing bead is located on the inside of the house for the following products:

  • Edgemont Picture Window
  • Cambridge Picture Window
  • S-Series Picture Window
  • OceanView Picture Window
  • Patio Door transoms and sidelites
  • All Geometric Windows

Can I paint my Viwinco windows?

No, painting your window will void your Viwinco warranty.

How do I clean my windows?

Visit our Care & Maintenance section to learn how to care for your windows.

Why is my window foggy?

If your window has become cloudy or foggy it could be a result of condensation, or indicate that there is moisture between the glass panes, which means that you have a seal failure. A Seal Failure is when the insulated glass unit’s (glass part of the window) seal is broken, and moisture is allowed into the sealed unit. The accumulation of moisture within the unit can appear as condensation, or fog, in between your two panes of glass.

Viwinco Warranty Policy for Seal Failures

  • For the original homeowner on a residential job, the seal failure is covered for the lifetime of the unit.
  • For the 2nd property owner under warranty transfer, the seal failure is covered up until the 20th Anniversary of the Manufacture Date.
  • For commercial applications, the unit is covered for 20-years.

Photographic evidence is required. 

For more information on the Viwinco warranty and a full list of coverage, in addition to easy-to-understand graphics, visit our Warranty Page.

If you need to process a Warranty Claim visit our Warranty Page.

Can I install blinds in the jamb of the window?

No, installing blinds into the jamb of the window will void the Viwinco warranty.

Can I make a left handed patio door right handed?

No, our doors are not designed to be interchangeable. Contact your distributor or local sales representative for further questions.

Visit Where to Buy to find a local distributor or contractor in your area.

Can I convert my single-hung window into a double-hung window?

No, our single-hung windows are not designed to be converted to a double-hung window. Contact your distributor or local sales representative for further questions.

Visit Where to Buy to find a local distributor or contractor in your area.

How do I take out my full screen out?

How To Replace an Extruded Full Screen in an S-Series Double-Hung Window

Follow the video below to help you remove your full screen.

Window Performance

Impact Windows

What is design pressure? Performance grade?

Design Pressure (DP)
According to the American Architectural Manufacturers Association (AAMA), DP is a rating that identifies the load induced by wind or other dynamic pressures. The higher a DP rating, the more resistant it is to the effects of wind and other pressures.

Performance Grade (PG)
A numeric designation that defines the performance of a product in accordance with AAMA standards. PG is determined upon successful completion and verification of all applicable tests (air, water, structure).

Are there additional tests beside air, water and structure that hurricane windows undergo?

Yes, to be a certified hurricane window, the window must pass an impact test. The test window is impacted by a “missile” (Viwinco uses a 9-lb. 2×4) and then subjected to 4,500 positive and 4,500 negative static pressure differentials. As part of the certification test, wind speeds 1.5 times the associated DP are cycled to ensure the window will meet greater wind loads.


What does condensation on the outside of my vinyl windows mean?

Nothing is wrong with your windows. The presence of moisture on the outside of your windows indicates that a specific set of atmospheric conditions exists and that the insulating glass is indeed performing as it was designed to. In this case, that insulation capability is what slows the flow of building heat through the glass and prevents warming of the exterior above the dew point.

Though there’s little to nothing you can do to prevent exterior condensation, you can try keeping draperies open to allow as much heat transfer through the glass as possible. Shrubs near windows can increase the humidity in that area and may need to be moved. 

How can I reduce the level of humidity in my home to combat condensation?

Condensation occurs when warm humid air meets a cool surface (glass window pane) causing it to condense and form water droplets. this is known as condensation. If you are experiencing condensation on the interior of your windows, it is likely due to a humidity buildup within the home. There are many sources of household humidity. The humidity that leads to condensation results from everyday life: taking showers, boiling water, humidifiers, water pans on radiators or wood stoves, kerosene heaters, drying laundry, and house plants also contribute to household humidity.

The construction of your home – the kind and amount of ventilation, the presence or absence of a basement – even the soil type and drainage patterns of the land on which it is built can add humidity as well. In many cases, you can reduce humidity simply by being aware of the sources and reducing your daily use – for example, taking shorter showers, or reducing humidifier usage. 

Here are more ideas for reducing humidity in your home:

  1. When using bathrooms, the kitchen, or the laundry room, turn on any built-in fans.
  2. Install an exhaust fan in your attic to draw moist air out of your home.
  3. Use a dehumidifier. And discontinue the use of any humidifiers or the placement of water pans on your radiators or wood stove.
  4. Open a door or window for a few minutes every day to air out your home. You can also open fireplace dampers and basement or attic louvers.
  5. During cold months, move your house plants to a sunroom or seldom-used room.
  6. Waterproof your basement floors and walls using moisture-sealing paint available at most hardware stores.

If your home still has excessive humidity issues after you’ve tried the above steps, you may have a more serious problem. Talk to a professional such as your architect or heating contractor for assistance. 

I’ve noticed condensation on the inside of my windows during colder months. Why does this happen?

Condensation is caused by household humidity. That fog or moisture you see occurs when warm humid air comes in contact with a cool surface. This is more common during winter months when your doors and windows are kept closed. A thin film of dew or frost on your windows is normal and will not damage them. However, if you see excessive condensation such as beads of water flowing down your windows or walls – that’s a sign of too much household humidity, which may need to be reduced.


How do I find my warranty label?

For assistance with locating your warranty label, visit our Label Diagrams page.

What do I do if the warranty label is missing?

The warranty label is very important, and without it, it is more difficult to find out details pertaining to your order. If your warranty label is missing however, here are some workarounds:

  • If the label is missing and you have other Viwinco windows that were ordered together we can use a warranty label from one of those windows.
  • If you don’t have any labels and have a copy of your invoice we can try to use that.
  • Contact your local distributor to see if they have information of your order on file.

How do I get my warranty labels from a picture or geometric window?

The warranty label on all fixed units is located on the interior side of the house, on the bottom sill. See our Label Diagram page for more information on the label location. You will then need to remove the glazing bead. 

How to remove the glazing bead on a picture window:

  • Remove the glazing bead by placing a moon knife or wood chisel into the space where the spline fits into the groove.
  • Tap the knife or chisel with a mallet, pushing the glazing bead away from the groove, until it can be removed by hand

I bought my windows when you were making windows for CertainTeed, are my windows still under warranty?

CertainTeed Claims:

Viwinco and CertainTeed are no longer affiliated. In 2007 CertainTeed sold their window program to Metal Industries at which time we decided to develop our own, new product line. Because of this, Viwinco does not have access to the parts required to service a CertainTeed window.

CertainTeed is the holder of your warranty and will honor any claims. You may process your claim through them directly. Listed below is their number to start the claim process.

CertainTeed Consumer Services phone: 1-888-454-7218

Quick Links

Trying to find something specific on our site? Our quick links section can help you quickly find things like: Locating a professional seller or installer, viewing architectural drawings or performance data, warranty registration, and the purchase journey for a buyer of Viwinco Windows

Where to Buy

Find the closest Viwinco Distributor, Contractor, or Installer.

Label Diagrams

Reference all of our product performance data.


View and register your warranty or submit a claim here.

Buyers Guide

Key information on the window buying process and Get a Quote tool.