RELIABILT Single Hung Windows
RELIABILT single hung windows have a fixed top sash and a bottom sash that slides up for ventilation. The most affordable window style.
RELIABILT single hung windows are the most affordable option in the lineup, starting at $79. The top sash is fixed (does not move) while the bottom sash slides up for ventilation. Available in the 3201 Series (budget) and 3500 Series (better energy rating). The bottom sash tilts in for easy cleaning from inside. Vinyl frame, dual-pane Low-E glass, maintenance-free.
Single Hung Specifications
| Bottom Sash | Slides up, tilts in for cleaning |
| Top Sash | Fixed (does not open or tilt) |
| Price Range | $79 - $180 depending on size and series |
| Energy Star | 3201: Northern zones. 3500: All US zones. |
| Sizes | Standard and custom. 24"x36" to 48"x60". |
Single hung costs 10-15% less than double hung because the fixed top sash is simpler to manufacture. The trade-off is less ventilation (only the bottom half opens) and the top sash cannot be tilted in for cleaning.
How to Choose a Single Hung Window
Sizing: Measure the rough opening width at three points (top, middle, bottom) and height at three points (left, center, right). Use the smallest measurement for each dimension. RELIABILT single hung windows come in standard sizes from 24"x36" up to 48"x60". If your opening falls between sizes, order the next size down and shim the gap.
Energy ratings: Look at U-factor and SHGC (Solar Heat Gain Coefficient). The 3201 Series has a U-factor around 0.30, which qualifies for Energy Star in northern zones. The 3500 Series adds argon gas fill and achieves lower U-factors, qualifying for all US climate zones. In cold climates, prioritize low U-factor. In hot climates, prioritize low SHGC to reduce cooling costs.
Climate considerations: Single hung windows have fewer moving parts than double hung, which means fewer potential air leak points. This makes them a practical choice in windy or cold regions. If you live in a humid climate, the fixed top sash eliminates one potential moisture entry point. For coastal areas, confirm the hardware is corrosion-resistant.
Series selection: Choose the 3201 for rental properties, utility rooms, or budget projects. Choose the 3500 for living spaces where energy efficiency and noise reduction matter more. Both use fusion-welded vinyl frames and dual-pane Low-E glass.
Color and grid options: RELIABILT single hung windows come in white and almond frame colors. Grid patterns include no grid, colonial, and prairie styles. Grids are between the glass panes (GBG), so they do not affect cleaning. Choose a grid pattern that matches your home's architectural style for a cohesive look.
Common Problems and Fixes
Condensation between panes: Moisture trapped between the two glass panes means the seal has failed. This cannot be repaired; the glass unit (called an IGU) needs to be replaced. Check your RELIABILT warranty, as seal failure is typically covered under the limited lifetime warranty.
Drafty around the frame: Feel for air leaks around the edges with a lit incense stick on a windy day. If air enters between the window and the wall, re-caulk the exterior and apply low-expansion foam to the gap between the frame and rough opening. If the draft comes from the sash meeting rail, the weatherstripping may need replacement.
Bottom sash won't stay up: Single hung windows use a balance system (usually a block-and-tackle or spiral balance) to hold the sash open. If the sash drops, the balance has worn out. Replacement balances are available at Lowe's. Match the weight rating and length of the original.
Sash hard to slide: Dirt and debris in the tracks are the most common cause. Clean the tracks with a vacuum and damp cloth. If the sash still sticks, apply a dry silicone spray to the track. Avoid oil-based lubricants, which attract more dirt.
Exterior condensation on the glass: Moisture on the outside surface of the glass on cool mornings is normal and actually indicates the Low-E coating is working by keeping heat inside. This type of condensation evaporates as the outdoor temperature rises and is not a defect.
Cracked or broken glass: If a pane cracks from impact or thermal stress, the entire insulated glass unit must be replaced. Do not attempt to replace a single pane in a dual-pane window. Contact Lowe's for a warranty claim or to order a replacement IGU matched to your window size and series.
Maintenance Guide
Cleaning vinyl frames: Wash the vinyl with mild soap and water. Avoid abrasive cleaners, bleach, or solvents, which can discolor or weaken the vinyl. A soft cloth or sponge works well. Clean at least twice a year, more often in dusty or coastal environments.
Lubricating tracks: Once a year, vacuum out the sash tracks to remove dust and debris. Apply a thin coat of dry silicone lubricant to the track surfaces. Do not use WD-40 or petroleum-based products, as they collect grime over time.
Replacing weatherstripping: The weatherstripping on the bottom sash compresses over time and loses its seal. Peel off the old strip and press in new self-adhesive V-strip or foam tape sized for vinyl windows. This is a low-cost fix that noticeably reduces drafts.
Checking seals: Inspect the exterior caulk line around the window frame each spring. If you see cracking or gaps, scrape out the old caulk and apply a fresh bead of exterior-grade silicone or polyurethane sealant. Also inspect the glazing seal where the glass meets the sash for any separation.
Screen maintenance: If your single hung window includes a half screen, remove it once a year and rinse with a garden hose. Inspect the frame corners for separation and the mesh for tears. A torn screen can be re-screened with a spline roller and replacement mesh from Lowe's, or the entire screen frame can be replaced inexpensively.
Hardware inspection: Check the tilt latches, sash lock, and keeper annually. Tighten any loose screws. If the lock no longer pulls the sashes tightly together at the meeting rail, the keeper may need to be repositioned slightly to restore a tight seal.
Frequently Asked Questions
What is the difference between single hung and double hung windows?
In a single hung window, only the bottom sash moves. The top sash is fixed in place. In a double hung window, both sashes slide and both tilt in for cleaning. Single hung costs 10-15% less but offers less ventilation and the fixed top sash is harder to clean from upper floors.
Can I use RELIABILT single hung windows as replacement windows?
Yes. RELIABILT single hung windows are available in both replacement (insert) and new construction configurations. Replacement versions fit inside your existing frame without exterior work. New construction versions have a nailing fin for mounting to bare framing.
How long do vinyl single hung windows last?
Vinyl windows typically last 20 to 30 years with proper maintenance. The vinyl frame itself does not rot, rust, or need painting. The most common failure point is the insulated glass seal, which may fail after 15-20 years. RELIABILT covers seal failure under its limited lifetime warranty.
Balances and weatherstripping may need replacement sooner, typically every 10-15 years, but these are inexpensive parts that are easy to swap.
Compare with double hung windows for better ventilation. For wide openings, sliding windows may be a better fit. See all RELIABILT window options and customer reviews.
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