Bellingham Window Two Sashes or One? Why It Matters More Than You'd Think
Walk into any window showroom in Whatcom County and you'll hear the terms "single-hung" and "double-hung" thrown around like everyone already knows the difference. Here's the short version: on a single-hung window, only the bottom sash moves up and down while the top sash stays fixed in place. On a double-hung window, both sashes slide, so you can open the window from the top, the bottom, or both.
That one mechanical difference drives almost everything else — price, cleaning, airflow, and how the window holds up against Bellingham's weather over the years.
How Each Style Handles Our Climate
Bellingham doesn't get brutal winters, but it gets something arguably harder on windows: a long stretch of damp, mossy, salt-tinged air coming off the bay, plus driving rain that finds every gap in a frame. A few points worth knowing before you choose:
- Ventilation control. A double-hung window lets you crack the top sash to vent warm, moist indoor air out while keeping the bottom closed — useful for cutting down condensation and the mildew that likes to creep in during our gray months.
- Weep holes and drainage. Both styles rely on weep holes to drain water that gets past the outer seal. In areas with heavy moss and organic debris — common under trees and near gutters throughout Whatcom County — those weep holes need to stay clear, or water backs up into the frame regardless of which style you own.
- Salt air exposure. Homes closer to Bellingham Bay see faster wear on hardware — balances, locks, and screen frames — from airborne salt. This isn't a single- vs. double-hung issue specifically, but it's a reason to ask about corrosion-resistant hardware no matter which style you pick.
Cleaning and Maintenance
This is where double-hung windows earn their reputation. Most double-hung windows built in the last couple decades tilt inward, so you can clean both sides of the glass from inside your house — a real advantage on a two-story home or anywhere ladder access is awkward. Single-hung windows with a fixed top sash usually mean you're outside on a ladder to clean that upper pane, which gets old fast when moss and mineral streaking build up on glass left exposed to our rain season after season.
Double-hung windows do have more moving parts — two sash tracks, two sets of balances — which means more components that can eventually need adjustment or replacement. Single-hung windows, with only one moving sash, are mechanically simpler and tend to need less upkeep over their lifespan.
Cost and Energy Performance
Single-hung windows are generally the more budget-friendly option, since there's less hardware and fewer moving parts to manufacture. Double-hung windows typically cost more, but for homeowners who want that top-vent airflow or easier interior cleaning, many find the difference worth it.
Energy performance between the two styles is close when both are installed correctly with a good weatherstrip seal — the bigger factor is installation quality and the window's overall construction, not which sash moves. A poorly installed double-hung window will underperform a well-installed single-hung one every time.
Beyond Single- and Double-Hung: Other Styles Worth Knowing
Hung windows aren't the only option, and depending on the part of the house, another style might actually be the better fit:
| Style | How It Opens | Good For |
|---|---|---|
| Casement | Cranks outward, hinged on one side | A tighter seal against wind-driven rain; easy full-window ventilation |
| Sliding | Sashes slide horizontally | Wide openings where a low profile matters, like over a kitchen sink |
| Awning | Hinged at the top, opens outward | Venting during rain since the sash itself deflects water |
| Fixed/Picture | Doesn't open | Maximizing view and natural light, no drafts or seals to maintain |
Casement windows deserve a mention for our area specifically — because they seal by compressing against the frame when cranked shut, they tend to resist driving rain and wind infiltration a bit better than a sliding sash design. That's a real consideration on exposed walls facing the water or open fields around the county.
Making the Call for Your Home
There's no universal right answer here. A lot of it comes down to which windows you're replacing, how the house is oriented, and how much you value easy interior cleaning versus a lower price point. A window on a shaded, moss-prone north wall has different priorities than one facing open wind on the water side of the property.
We install and service single-hung, double-hung, and several other window styles, and we're happy to walk your specific home with you before you decide anything. If you'd like an honest look at what makes sense for your house, reach out for a free, no-pressure estimate — no obligation, just straight answers.