Mountain States Building Products maintains a limited selection of in-stock windows and doors at our Denver, Colorado location. However, most of our products - including Andersen Windows, Weather Shield Windows, Loewen Windows, Cascade Windows, and Arcadia Custom Windows - are ordered to specification for your project. Because we serve Colorado's elite home builders, multi-family contractors, and commercial contractors, most of our orders are custom configured to fit your design, needs, and budget. We recommend calling us at 303-377-8566 or visiting our Denver showroom (Mon–Fri, 9am–4pm) to discuss availability and lead times for your specific project.

Mountain States Building Products is a window and door supplier, not an installation company. We specialize in providing turnkey window and door solutions to home builders, commercial contractors, and multi-family developers along Colorado's Front Range. However, we work closely with a network of trusted and experienced installers and can recommend qualified professionals in your area. Our team also provides blueprint reviews, product knowledge support, and job site delivery to make the installation process as seamless as possible for you and your contractor.

Our Denver showroom is open Monday through Friday, 9:00am – 4:00pm. We are closed on Saturdays and Sundays. If you'd like to visit our showroom to see products from Andersen, Loewen, Weather Shield, Cascade, Pacific Accent, Velux Skylights, and more, we encourage you to plan your visit during the week. You can also reach us anytime by calling 303-377-8566 or submitting a quote request at mountainstatesinc.com.

Choosing the right window material depends on your project's style, performance goals, maintenance preferences, and budget. 

Vinyl-Clad Wood Windows - These combine the warmth and beauty of a real wood interior with a durable, low-maintenance vinyl exterior that protects against the elements. Andersen's 200 Series and 400 Series fall into this category, with the 400 Series offering more sizes, colors, and customization options than the value-focused 200 Series. 

Vinyl windows (like our Cascade Windows line) are made from PVC and are one of the most affordable and low-maintenance options on the market. They offer excellent energy efficiency, resist moisture and rot, and never need painting. They are ideal for budget-conscious builders and homeowners on Colorado's Front Range. The trade-off is that vinyl has less rigidity than other materials and may not suit ultra-high-end custom homes aesthetically.

Best for: Production homes, multi-family projects, replacement windows.

Composite Windows (Fibrex®) - Andersen's proprietary Fibrex® composite material is twice as strong as vinyl, resists warping, cracking, and fading, and requires minimal maintenance. The 100 Series is made entirely from Fibrex®, making it an excellent low-maintenance alternative to vinyl with outstanding durability and energy efficiency. 

Best for: Mid-range custom homes, replacement projects.

Aluminum Clad-Wood Windows - These feature a beautiful natural wood interior with a heavy-duty aluminum-clad exterior for superior weather resistance and design flexibility. Andersen's E-Series is a fully customizable aluminum clad-wood line, offering virtually unlimited sizes, colors, and wood species for premium architectural projects. 

Whether you're looking for an affordable, low-maintenance solution or a fully customized architectural window, Mountain States can help you select the Andersen series that best fits your home and budget.

Best for: Custom homes, luxury residential, architect-designed projects

Contact Mountain States Building Products at 303-377-8566 for a detailed quote based on your specific project needs.

Understanding window performance ratings is essential when selecting the right windows for your Colorado home or commercial project. Here's what each rating means:

U-Value (U-Factor)

The U-Value measures how well a window insulates - specifically, how much heat is lost or gained through the window. Lower U-Values = better insulation. In Colorado's cold climate, a low U-Value is critical. Energy-efficient windows from brands like Andersen, Weather Shield, and Loewen often achieve U-Values as low as 0.20 - 0.25, especially with triple-pane glass options.

SHGC (Solar Heat Gain Coefficient)

SHGC measures how much solar radiation passes through the glass. It ranges from 0 to 1 — lower values = less heat gain. In Colorado, the right SHGC depends on your project's orientation and climate zone. South-facing windows may benefit from a higher SHGC to capture passive solar heat in winter, while west-facing windows may need a lower SHGC to reduce summer heat gain. Our team at Mountain States can help you select the right SHGC for your Front Range project.

STC (Sound Transmission Class)

STC rates how well a window blocks sound. Higher STC ratings = better sound insulation. This is particularly important for homes near busy roads, highways, or Denver's urban areas. Specialty laminated glass and triple-pane options can significantly improve STC ratings. Ask us about acoustic glass options for your project.

DP/PG Rating (Design Pressure / Performance Grade)

DP (Design Pressure) or PG (Performance Grade) measures a window's ability to withstand wind, water, and structural loads. Higher ratings = stronger, more weather-resistant windows. In Colorado, where wind loads can be significant — especially in mountain communities — choosing windows with the appropriate DP/PG rating is critical. Our team is well-versed in Colorado building codes and can ensure your window selections meet local performance requirements.

All three brands are excellent choices for custom homes, and Mountain States Building Products is proud to carry all three. The "best" choice depends on your project's design, budget, and performance requirements:

Andersen Windows & Doors

Andersen is one of the most recognized and trusted window brands in the country. Their A-Series and E-Series lines are ideal for high-end custom homes, offering exceptional design flexibility, beautiful aesthetics, and outstanding performance. Andersen offers a wide range of materials, colors, and hardware options. Their 400 Series is a popular mid-to-high-end option for custom Colorado homes.

Best for: Custom homes where brand recognition, wide product availability, and a broad range of price points are important.

Weather Shield Windows & Doors

Weather Shield is a premium manufacturer known for its exceptional craftsmanship and high-performance windows. Weather Shield windows are particularly well-suited to Colorado's challenging climate, offering excellent energy performance, custom sizing, and beautiful wood interiors with durable exteriors. Weather Shield is a favorite among Colorado's top custom home builders.

Best for: High-end custom homes where performance and craftsmanship are top priorities.

Loewen Windows& Doors

Loewen is a Canadian luxury window manufacturer known for producing some of the most beautiful and high-performing windows in the world. Loewen specializes in all-wood and aluminum clad-wood windows with extraordinary attention to detail. If your custom home demands the absolute best in aesthetics, craftsmanship, and performance — Loewen is the pinnacle choice.

Best for: Ultra-luxury custom homes and architect-designed projects where no compromises are acceptable.

Our recommendation: Visit our Denver showroom and speak with one of our experts. With over 100 years of combined experience, our team will help you select the right manufacturer for your specific project, design vision, and budget.

Andersen offers multiple product lines to serve different budgets and project types. Here's a quick breakdown:

Andersen 100 Series

Made with Fibrex® composite material (a blend of wood fiber and thermoplastic polymer), the 100 Series is Andersen's most durable and low-maintenance entry-level option. It's twice as strong as vinyl, resists rot and warping, and is a great choice for replacement windows or budget-sensitive new construction.

Andersen 200 Series (Perma-Shield®)

The 200 Series features a wood interior with a vinyl exterior cladding. It offers a traditional look with good durability. However, this series has been largely phased out in favor of more advanced product lines.

Andersen 400 Series

The 400 Series is Andersen's most popular line for custom and semi-custom homes. It features a wood interior (paintable/stainable) and a durable composite exterior (Perma-Shield). It offers excellent energy performance, a wide range of styles, and good value for quality-conscious builders and homeowners.

Andersen A-Series

The A-Series is Andersen's premium product line, offering the greatest level of design customization. It features a wood interior and aluminum exterior cladding. The A-Series offers more size options, more color choices, more hardware options, and higher performance ratings than the 400 Series. Ideal for luxury custom homes and architect-designed projects.

Andersen E-Series (Eagle Windows)

The E-Series (formerly Eagle Windows) is Andersen's ultimate luxury line, offering fully custom wood windows with virtually unlimited design options. The E-Series is ideal for projects where maximum customization, premium materials, and exceptional aesthetics are required.

Mountain States Building Products offers a full range of glass options through our premium window brands. Here's an overview:

Dual Pane (Double Pane) Glass

Dual pane windows feature two panes of glass with an insulating gas (typically argon or krypton) between them. This is the industry standard for energy-efficient windows and is suitable for most Colorado residential and commercial applications. Low-E coatings are typically applied to improve thermal performance.

Triple Pane Glass

Triple pane windows add a third pane of glass, further improving insulation and U-Values. Triple pane is an excellent choice for Colorado's mountain communities, high-altitude homes, or any project where superior energy efficiency is a priority. Brands like Loewen, Weather Shield, and Andersen all offer triple pane options.

Specialty Glass Options

Low-E Glass: Reflects heat while allowing light to pass through - essential for Colorado's high UV environment

Laminated Glass: Improves STC (sound ratings) and provides shatter resistance (safety glass)

Tempered Glass: Required by code in certain locations (near doors, floors, etc.)

Obscure/Privacy Glass: For bathrooms, sidelights, and privacy applications

Decorative Glass: Custom patterns, textures, and art glass options available through brands like Andersen E-Series and Loewen

Impact-Resistant Glass: For areas requiring hurricane or impact ratings

Tinted Glass: Bronze, gray, and other tints to control solar gain.

Ask our team at Mountain States Building Products about the right glass package for your Colorado project.

Warranty coverage varies by manufacturer. Please refer to each manufacturer for updated warranty policies:

Andersen Windows & Doors

Weather Shield Windows & Doors

Loewen Windows & Doors

Cascade Windows

Velux Skylights

Lead times for windows and doors vary significantly depending on the manufacturer, product line, customization level, and current demand. As a general guideline:

Manufacturer Typical Lead Time

• Cascade Windows (Vinyl) 3–6 weeks
• Andersen 400 Series 4–8 weeks
• Andersen A-Series / E-Series 8–14 weeks
• Weather Shield 8–14 weeks
• Loewen 10–16 weeks
• Arcadia Custom 10–16 weeks

Lead times can fluctuate due to supply chain conditions, seasonality, and order volume. Contact Mountain States Building Products today at 303-377-8566 for the most current lead time estimates. We understand that time is money on your project, and we work hard to keep your build on schedule.

To provide an accurate quote for your windows and doors, our team at Mountain States Building Products will typically need the following:

• Project type – New construction, remodel, replacement, commercial, or multi-family
• Project location – City/county in Colorado (important for building codes and energy requirements)
• Blueprints or plans – If available, a blueprint review helps us provide the most accurate quote
• Window and door schedule – A list of window and door sizes, types (casement, slider, single-hung, etc.), and quantities
• Preferred manufacturer and product line – Andersen, Weather Shield, Loewen, Cascade, etc. (or we can help you choose)
• Frame material preference – Vinyl, composite, or aluminum clad-wood
• Glass package preference – Dual pane, triple pane, Low-E, etc.
• Interior and exterior finish/color preferences
• Hardware preferences
• Timeline/required delivery date

The more information you can provide, the more accurate your quote will be. Call us at 303-377-8566 or visit our Denver showroom to get started!

Mountain States Building Products primarily serves home builders, commercial contractors, and multi-family developers and does not typically offer on-site measurement services for residential replacement projects. For replacement window projects, we recommend working with a qualified window installer who can take precise field measurements. We can then use those measurements to configure and order the correct replacement windows from our premium brands. Contact us at 303-377-8566 to discuss your replacement project and get connected with a trusted installer in your area.

Most window manufacturers, including Andersen, Weather Shield, and Loewen, provide warranties that cover product defects in materials and workmanship, but labor warranties are typically the responsibility of the installing contractor, not the manufacturer.

Some manufacturers, like Velux, offer special installer programs that include an installation warranty when the product is installed by a Velux-certified installer.

Here's a general breakdown:

Manufacturer Labor Warranty

Andersen - Not covered by manufacturer — installer's responsibility

Weather Shield - Not covered by manufacturer — installer's responsibility

Loewen - Not covered by manufacturer — installer's responsibility

Velux - Up to 10-year installation warranty with certified installer

We strongly recommend working with experienced, reputable installers and confirming their labor warranty terms before starting your project. Mountain States Building Products can help connect you with trusted installers in Colorado.

Mountain States Building Products is primarily a window and door supplier and does not provide field service or repair work. If your windows are out of warranty or were not purchased through us, we recommend:

• Contacting the manufacturer directly - Many manufacturers have service departments or can recommend certified service technicians
• Working with a qualified window service contractor - We may be able to provide a referral to a trusted service professional in the Denver/Front Range area
• Purchasing replacement parts through us, in some cases, we may be able to source replacement hardware, glass, or components for windows from brands we carry, such as Andersen, Weather Shield, or Loewen.

Call us at 303-377-8566 and we'll do our best to point you in the right direction.

Mountain States Building Products provides professional job site delivery across Colorado's Front Range and surrounding areas, including:

• Denver Metro Area
• Boulder and Broomfield County
• Fort Collins and Northern Colorado
• Colorado Springs
• Castle Rock and Douglas County
• Summit County and Mountain Communities
• Vail, Aspen, and Western Slope (on a project basis)

We understand that on-time delivery is critical to keeping your project on schedule. Our team takes exceptional care in loading, handling, and delivering your windows and doors to the job site when you need them. Call 303-377-8566 to discuss delivery to your specific location.

Yes! While Mountain States Building Products does not perform installations directly, we have built strong relationships with trusted and experienced window and door installers throughout Colorado's Front Range over our 30+ years in business. We are happy to provide referrals to qualified installers who have experience with our products from Andersen, Loewen, Weather Shield, Cascade, and our other premium brands. Call us at 303-377-8566 or visit our Denver showroom to request an installer recommendation for your area.

Breather tubes (also called capillary tubes or pressure equalization tubes) are small tubes inserted into insulated glass units (IGUs) to help equalize air pressure between the glass panes and the surrounding environment. They are particularly important in high-altitude locations like Colorado, where the significant difference in altitude between where the windows are manufactured (often at lower elevations) and where they are installed (Denver at 5,280 feet, or mountain communities even higher) can cause the sealed air space between the glass panes to expand or contract due to pressure differences.

Why are they important in Colorado?

Without breather tubes, the pressure differential between the factory and a high-altitude installation site can cause the glass to bow inward or outward, distorting the view through the window and potentially stressing the seal. Breather tubes allow the pressure to equalize during shipping and installation, after which they are sealed.

Are they included in my quote?

Yes - for many projects in Colorado, particularly at higher elevations, breather tubes are a standard or recommended addition to your insulated glass units. Our team at Mountain States Building Products will ensure your windows are properly specified for your project's altitude. This is just one example of our expert product knowledge and attention to detail that sets us apart from other Colorado window suppliers.

If you're seeing fog or condensation on the exterior surface of your windows in the morning after rain or on cool, humid mornings, this is actually a sign that your windows are working correctly! Here's why:

Exterior Condensation (Normal)

Modern high-performance, energy-efficient windows (like those from Andersen, Weather Shield, and Loewen) are so well-insulated that the exterior glass surface stays cooler than the surrounding air temperature. When warm, humid air contacts the cool glass surface, moisture condenses on the outside - just like condensation on a cold glass of water on a summer day. This is a sign your windows are doing their job.

Interior Condensation (May Indicate High Indoor Humidity)

If you're seeing fog or condensation on the interior surface of your windows, this typically indicates that your indoor humidity level is too high relative to the outdoor temperature. This can usually be addressed by improving ventilation or using a dehumidifier.

Condensation Between the Panes (Seal Failure)

If you see fog or moisture between the glass panes (inside the insulated glass unit), this is a sign that the seal has failed and the insulated glass unit needs to be replaced. This is covered under warranty for most manufacturers we carry. Contact Mountain States Building Products at 303-377-8566 for warranty assistance.

The lifespan of your windows depends on the material, manufacturer, quality of installation, and maintenance. Here are general guidelines:

• Window Type Expected Lifespan
• Vinyl Windows (Cascade) 20–40 years
• Composite Windows (Andersen 100/Fibrex) 30–40+ years
• Aluminum Clad-Wood (Andersen 400/A-Series) 30–50+ years
• Wood/Aluminum Clad (Weather Shield, Loewen) 40–60+ years

Premium brands like Loewen and Weather Shield are built to last for generations when properly maintained. Factors that can shorten window lifespan include:

• Poor installation (one of the most common causes of premature failure)
• Lack of maintenance (especially for wood windows — periodic repainting or staining is required)
• Seal failure in insulated glass units (IGUs typically last 15–25 years before potential seal failure)
• Extreme UV exposure (Colorado's high UV environment can accelerate wear on inferior products)

At Mountain States Building Products, we help you select high-quality products built to last in Colorado's unique climate. Call us at 303-377-8566 to discuss the best window investment for your project.

Choosing the right window style depends on your design goals, ventilation needs, space constraints, and budget. Here's a quick guide:

Casement Windows

What they are: Hinged on one side, cranked open outward (like a door)

Best for: Locations where maximum ventilation is desired; they open fully, catching cross-breezes

Energy performance: Excellent - when closed, the sash presses tightly against the frame, creating a strong seal

Ideal locations: Living rooms, bedrooms, areas above counters where reaching up to open a window is needed

Popular brands at Mountain States: Andersen 400 Series, A-Series, Weather Shield, Loewen

Single-Hung Windows

What they are: The bottom sash slides up; the top sash is fixed

Best for: Traditional home designs; cost-effective option

Energy performance: Good

Ideal locations: Bedrooms, bathrooms, utility rooms

Popular brands at Mountain States: Cascade Windows, Andersen 100/400 Series

Double-Hung Windows

What they are: Both the top and bottom sashes slide up and down; easier to clean

Best for: Traditional and transitional home designs

Energy performance: Good

Ideal locations: Throughout the home; popular in bedrooms and living areas

Slider Windows

What they are: Sashes slide horizontally

Best for: Contemporary and modern home designs; wide openings; areas with limited vertical space

Energy performance: Good

Ideal locations: Living rooms, basements, areas where a wide horizontal view is desired

Fixed/Picture Windows

What they are: Non-operable windows that do not open

Best for: Maximizing views and natural light; energy performance is excellent (no moving parts)

Ideal locations: Great rooms, stairwells, accent locations

Our team at Mountain States Building Products will review your blueprints and design goals to help you select the right window style for every opening in your home. Visit our Denver showroom or call 303-377-8566 to get started.

Casement windows are identified by the side on which the hinges are located, as viewed from the exterior of your home.

Left-Hand Casement (LC): Hinges are on the left side, and the window opens outward from the left.

Right-Hand Casement (RC): Hinges are on the right side, and the window opens outward from the right.

Stationary (Picture) Window: Does not open and has no operating sash.

To determine which type you have, simply stand outside your home and look at the window. If the hinges are on the left, it's a left-hand casement. If the hinges are on the right, it's a right-hand casement. This exterior view is the standard used when ordering replacement windows to ensure the correct operation and fit.

Pro Tip: When in doubt, always confirm with your architect, builder, or our expert team before placing your order. Call us at 303-377-8566, we're happy to help!