Andersen storm windows provide an essential layer of exterior protection, enhancing home energy efficiency, sound abatement, and seasonal ventilation control. Selecting the correct model requires understanding frame materials, glass packages, and structural compatibility with existing primary windows.
Understanding Andersen Storm Window Engineering and Design
Storm windows serve as an exterior secondary glazing system installed over existing primary windows. Andersen Corporation engineers these units to improve thermal performance, reduce air infiltration, and protect primary windows from harsh weather elements.
The structural integrity of an Andersen storm window relies heavily on heavy-gauge extruded aluminum frames, reinforced corners, and durable factory finishes. Unlike lightweight or generic alternatives, Andersen units are engineered with specific drainage channels—often referred to as weep systems—that safely direct accumulated condensation or driven moisture back to the exterior, preventing wood rot on historic or standard primary frames.
Core Component Breakdown
- Extruded Aluminum Frames: Provides structural rigidity, resistance to warping, and a high strength-to-weight ratio.
- Low-E Glass Options: Reflects radiant heat back inside during winter and repels solar heat gain during summer months.
- Interlocking Meeting Rails: Reduces air leakage by creating a tight, overlapping seal when the window is locked.
- Weatherstripping: High-density pile or bulb weatherstripping seals gaps along the perimeter and sash interfaces.
Key Product Series and Configuration Options
Andersen offers multiple product series tailored to different architectural styles, climate requirements, and installation preferences. Evaluating these options ensures long-term satisfaction with both functionality and visual aesthetics.
| Series Name | Primary Frame Material | Glass Options | Operating Style | Best Suited For |
|---|---|---|---|---|
| Andersen 3-Track | Extruded Aluminum | Clear Glass / Low-E Glass | Double-Hung (Both sashes move) | Maximum ventilation and effortless seasonal adjustment |
| Andersen 2-Track | Extruded Aluminum | Clear Glass / Low-E Glass | Double-Hung (One moving glass, one screen) | Standard multi-story applications requiring fixed screen placement |
| Andersen Self-Storing | Extruded Aluminum | Clear Glass / Low-E Glass | Combination (Glass and screen slide independently) | Quick conversion between seasonal glass and screen modes |
| Emco ForeverView | Aluminum / Composite mix | Standard Annealed | Various configurations | Budget-conscious projects prioritizing durability |
Selecting Between 2-Track and 3-Track Systems
Choosing between track systems dictates how homeowners manage seasonal ventilation. A 3-track storm window houses two glass sashes and one insect screen on independent tracks, allowing both upper and lower sashes of the primary window to be exposed for airflow without removing components. A 2-track system simplifies this by keeping the screen permanently positioned on the exterior upper track while a single movable glass sash travels vertically below it.
Energy Efficiency and Thermal Performance Metrics
Energy performance is a primary driver for storm window investments. According to the U.S. Department of Energy, installing exterior storm windows can reduce whole-house air leakage by up to 10% and lower annual heating and cooling costs significantly.
Evaluating Low-E Coatings and Gas Fills
Traditional clear glass storm windows primarily block wind and provide a basic thermal buffer. Upgrading to Low-E (Low-Emissivity) glass dramatically changes the performance profile:
- Solar Heat Gain Coefficient (SHGC): Low-E coatings reduce the amount of solar radiation entering the home, keeping interior spaces cooler in warm climates.
- U-Factor: Measures the rate of non-solar heat loss. Lower U-factors indicate superior insulation capabilities, keeping interior glass surfaces warmer and reducing condensation risks.
- UV Protection: Minimizes ultraviolet light penetration, safeguarding interior furnishings, drapery, and hardwood floors from premature fading.
Step-by-Step Measuring and Installation Guide
Precise measurement is the single most critical factor in storm window installation. Because window openings can shift or settle over time, taking measurements at multiple points ensures a proper fit.
Phase 1: Measuring the Exterior Opening
- Width Measurement: Measure the distance between the exterior wood brickmoulds or metal channels at three distinct locations: top, middle, and bottom. Record the narrowest measurement.
- Height Measurement: Measure from the highest point of the sloped exterior sill up to the underside of the upper brickmould or head jamb. Measure on the left, center, and right, recording the shortest dimension.
- Squareness Check: Measure diagonally from corner to corner in both directions. If the diagonal measurements differ by more than a quarter-inch, the opening is out of square, requiring shims or custom ordering.
Phase 2: Installing the Storm Window Unit
- Prepare the Sill: Ensure the sill is clean, dry, and structurally sound. Apply a generous bead of exterior-grade silicone caulk along the top of the sill and up the outer edges of the brickmould to create a water-resistant perimeter seal.
- Position the Unit: With assistance, lift the Andersen storm window and center it squarely against the exterior mounting surface, ensuring the weep holes face downward toward the exterior.
- Secure the Frame: Drive temporary screws through the pre-drilled fastening holes in the upper corners of the frame. Check for plumb and square operation of the sashes before driving all remaining mounting screws supplied by the manufacturer.
- Seal the Exterior: Run a clean bead of sealant along the top and side exterior edges of the storm window frame where it meets the house siding or trim. Leave the bottom sill unsealed to allow any trapped moisture to escape freely through the weep system.
Maintenance, Troubleshooting, and Common Issues
Maintaining Andersen storm windows extends their functional lifespan and preserves operational smoothness. Routine upkeep prevents minor environmental debris buildup from causing mechanical failures.
Recommended Seasonal Maintenance Schedule
- Spring Cleaning: Wash glass surfaces with a mild dish soap and water solution. Inspect and clear weep holes of any spider webs, dirt, or organic debris.
- Autumn Inspection: Check weatherstripping for compression fatigue or tearing. Lubricate sliding tracks and mechanical latches with a dry silicone spray—avoid petroleum-based lubricants that attract dust and grit.
Troubleshooting Operational Resistance
If a storm window sash becomes difficult to raise or lower, inspect the side channels for accumulated grime or paint buildup. Never force a stuck sash, as this can bend the aluminum frame or crack the glass panel. Clean the tracks thoroughly and apply a light coating of dry lubricant. If sashes drift downward on their own, adjust the tension springs or balance mechanisms located within the side jambs according to the manufacturer specifications.
Comprehensive Comparison: Andersen Storm Windows vs. Replacement Windows
Homeowners often debate whether to install exterior storm windows or completely replace existing primary windows. Each approach serves distinct financial and structural goals.
| Decision Factor | Andersen Storm Windows | Full Replacement Windows |
|---|---|---|
| Upfront Financial Investment | Low to Moderate | High to Very High |
| Installation Time | Hours (DIY or Professional) | Days (Requires Professional Contractors) |
| Preservation of Historic Fabric | High (Retains original windows/trim) | Low (Removes original historic elements) |
| Energy Efficiency Gains | Moderate to High (Close to double-pane performance) | Maximum (High-performance new construction) |
| Structural Alteration | None (Surface mounted to exterior) | Substantial (Exposes wall framing) |
Frequently Asked Questions
Can Andersen storm windows be installed on any type of primary window?
Andersen storm windows are versatile and can be installed on most standard double-hung, single-hung, and sliding primary windows, provided there is a flat exterior mounting surface such as wood brickmould or a designated aluminum panning channel. However, casement and awning windows require specialized operating hardware that standard storm windows cannot accommodate.
How do Low-E glass storm windows affect indoor plant growth?
Low-E coatings block a significant portion of ultraviolet and infrared light spectrums, which can slightly reduce the growth rate of sun-loving indoor houseplants placed directly on the windowsill. Relocating sensitive plants to a sunroom or providing supplemental artificial grow lighting easily resolves this issue.
Are Andersen storm windows suitable for historic preservation projects?
Yes, exterior storm windows are frequently approved by historic preservation boards because they protect original, irreplaceable wood windows and historic glass from weather degradation without altering the visible architectural character of the building's exterior facade.
What is the expected lifespan of an Andersen aluminum storm window?
With routine cleaning and minimal seasonal maintenance, high-grade aluminum Andersen storm windows typically last between 25 and 40 years. The durable factory finish resists rust and fading, though weatherstripping and movable latches may require occasional replacement over extended periods.
Can I install Andersen storm windows myself as a DIY project?
Yes, standard sizes are designed for straightforward DIY installation using basic hand tools, a cordless drill, and exterior sealant. However, multi-story installations or oversized custom units require professional handling to ensure safe positioning and weather-tight sealing.
Professional Recommendation
For homeowners seeking to maximize thermal efficiency, minimize exterior noise, and protect aging primary windows without undertaking a disruptive, costly full-scale window replacement project, Andersen storm windows represent an optimal, cost-effective engineering solution. Prioritize precise field measurements and select Low-E glass packages to maximize long-term energy savings and interior comfort.
