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ES Windows Construction in Hillsborough, CA | San Bernardino Contractors
We provide independent ES Windows installation, retrofit, and re-glazing across Hillsborough’s estate and hillside custom-home market. We’re not manufacturer-authorized, and we don’t pretend to be. What we bring instead is decades of hands-on experience with ES Windows aluminum sliders, fixed picture assemblies, and dual-pane IGUs, plus the local knowledge that matters when your lot slopes, your oaks are protected, and your mid-century framing has shifted. Call (855) 473-5620 for a free estimate.
Hillsborough isn’t a tract-home town. The houses here sit on generous lots with mature oaks, steep grades, and a fair share of original 1960s and 1970s window systems that have outlived their seals. When an ES Windows unit fogs or a slider starts binding, the fix usually isn’t as simple as swapping glass. The opening itself has often moved. We plan for that from the start. Our full ES Windows service line covers everything from single-sash repairs to complete replacement and new-construction glazing on custom additions. ES Windows sales & service is the core of this work, and we handle the flashing, the waterproofing, and the structural re-squaring, not just the glass.
Why Hillsborough Residents Choose Us for ES Windows Service
Ruben Castillo, our owner, grew up watching his uncle reroof houses and frame garages on the Westside of San Bernardino. That education taught him something a lot of window contractors miss: the rough opening is half the job. He completed his construction technology training at San Bernardino Valley College, where he learned to read plans and understand load paths before he ever touched a window jamb. Those two decades of framing, concrete, and whole-home remodel work across the Inland Empire carry straight into how we approach General Contractor – Hillsborough ES Windows work in Hillsborough.
We see the failure modes other crews miss because we’re a full-service general contractor first. We understand when a binding sash is the window or the wall. We know how a protected oak’s root zone changes where we can stage materials and set scaffolding. And because we work across the Hillsborough service area regularly, we’re familiar with the mid-century custom homes and hillside rebuilds that dominate this town. That local repetition matters. It means we’ve already seen your window problem before we walk your lot.
Styles & brands we work with







Common ES Windows Construction Problems We Solve in Hillsborough
The ES Windows units in Hillsborough rarely fail in isolation. Here are the patterns we see most, tied to what this town actually throws at a window system:
- Fogged or failed dual-pane IGU seals – Shaded, north-facing walls under Hillsborough’s oak canopy hold moisture longer than sun-exposed elevations. The seal between panes degrades, condensation forms inside the glass, and the view goes hazy. We re-glaze with OEM-matched IGUs when available or quality aftermarket units when ES Windows has discontinued the exact spec.
- Water intrusion and rot behind ES aluminum frames – Original installations on sloped Hillsborough lots often lacked proper sill pans or flashing. After one or two wet winters, water wicks behind the frame, rots the rough sill, and spreads into the sheathing. We tear out the window, repair the structural damage, re-flash with sloped sill pans, and reset the unit properly.
- Racked or binding sashes on hillside lots – When retaining walls shift and grades settle, the wall framing moves with it. The window opening goes out of square, and the sash binds, sticks, or won’t latch. We re-square the rough opening before setting a new ES Windows unit, because putting a square window into a parallelogram opening just transfers the stress into the glass.
- Corroded or pitted aluminum frames and worn weatherstripping – Wooded Hillsborough lots mean constant leaf litter and moisture against exterior frames. Older ES Windows aluminum shows pitting and corrosion at the corners and along the bottom rail. We replace worn weatherstripping, treat surface corrosion, and swap the unit when the frame is structurally compromised.
- Outdated single-pane ES Windows units on original mid-century homes – Many Hillsborough estates still carry their original aluminum single-pane windows. They rattle, leak air, and do almost nothing for energy efficiency. We replace them with dual-pane low-E ES Windows units sized to the existing openings, or spec new construction for additions and rebuilds.
ES Windows Service in Hillsborough: What Local Conditions Mean for Your Equipment
Here’s the Hillsborough-specific wrinkle that doesn’t apply to Burlingame, San Mateo, or most of the Peninsula: protected native oaks trigger town arborist review before we can disturb a root zone. That review shapes sequencing on almost every window project on an estate lot. We don’t wait until excavation day to find out we can’t stage materials under a heritage oak’s canopy. We map the tree-protection zones, plan scaffolding and material drops around the root setbacks, and sometimes stage window delivery in phases. On a recent project off the wooded lanes near Lower Hillsborough, our crew replaced a run of fogged ES Windows dual-pane units in a mid-century custom home where hillside wall movement had racked several openings. We re-squared and re-flashed the rough openings with new sill pans, set OEM-matched replacement units, and coordinated staging to stay clear of the protected-oak root zone. The seal failures stopped, the sliders close cleanly, and the arborist review added about ten days to the schedule. That’s normal here, and a contractor who doesn’t plan for it ends up with windows sitting in a driveway while the town sorts out paperwork.
The other Hillsborough reality is grading. Sloped lots and retaining walls move. We don’t treat a binding ES Windows sash as a glass problem until we’ve checked the wall. On several hillside estates, we’ve found the window was square when it was installed twenty years ago and the wall has since shifted a quarter inch. That’s not a defect in the ES Windows product; it’s a site condition. The fix is opening re-squaring and re-flashing, not just a new sash.
ES Windows Models & Products We Service in Hillsborough
We work on the full ES Windows range that shows up in Hillsborough homes, with the model families and glazing systems below:
- ES Windows vinyl single-hung and slider replacement series – the builder-original units common in 1980s-2000s Peninsula homes.
- ES Windows aluminum sliding glass doors and fixed picture-window assemblies, particularly on custom and hillside builds where wide openings and view walls are the focus.
- ES Windows dual-pane and low-E insulated glass units (IGUs) used in mid-century and later custom construction.
On parts, we’re honest about OEM versus aftermarket. Some ES Windows sashes and hardware are still in the supply chain; when they are, we order them. When a line’s been discontinued and OEM parts are gone, we use quality aftermarket IGUs and hardware that match the original performance spec. We don’t push a full window replacement when a re-glaze or a single sash swap will hold up. If the frame is sound and the glass is the only failure, we say so. If the frame is corroded or the opening is racked beyond re-squaring, we tell you that too.
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AfterES Windows Service Pricing in Hillsborough
Pricing depends on the scope: a single re-glazed IGU costs far less than re-flashing and resetting an entire wall of windows. Here are the ranges we quote for the most common Hillsborough ES Windows projects:
| Service | Typical Range |
|---|---|
| Window Replacement | $4,500 – $15,000 |
| Impact Window Installation | $8,000 – $25,000 |
| Roof Repair (related flashing/waterproofing work) | $400 – $1,800 |
| Home Addition (with ES Windows glazing spec’d into new openings) | $45,000 – $130,000 |
What drives cost in Hillsborough: access on sloped lots, scaffolding requirements around protected oaks, the number of openings that need re-squaring, and whether we’re re-glazing existing sashes or doing full replacements. A free estimate means we walk the site, check the openings, and give you a written line-item quote before any work starts. Call (855) 473-5620 to schedule yours.
Serving Hillsborough, CA — Our Local Coverage Area
We’re based in the Hillsborough area and know this community well. Use the map below to see our service coverage — if you’re nearby, we can almost certainly help.
FAQs – ES Windows Construction in Hillsborough
Yes. When retaining walls shift or grades settle, the wall framing moves and the rough opening goes out of square. A racked opening transfers stress into the window frame and sash, which is why some Hillsborough ES Windows units bind or fail even when the glass itself is fine. We check opening squareness on every service call and re-square the rough framing before setting a new unit.
It can, and it routinely does. If a window opening is within a protected oak’s root zone, the town arborist must review before we disturb the area. That affects where we stage materials, place scaffolding, and sequence excavation for new openings. We plan for this from the first site visit and build the review time into the schedule. Call (855) 473-5620 to get an accurate timeline for your property.
It depends on the symptom. Fogged glass with no water staining points to a failed IGU seal. Water intrusion with staining or rot at the bottom corners points to a flashing or sill pan failure, not the glass. On shaded Hillsborough north-facing walls, both can happen at once. We diagnose the actual failure mode before recommending re-glazing or replacement, so you don’t pay for glass when the flashing is the problem.
Yes. We spec ES Windows glazing into new construction openings on custom additions and hillside rebuilds throughout Hillsborough. The units are ordered to the exact rough opening dimensions, and we coordinate the order with the town’s tree and design review timelines so the windows arrive when framing is ready. We also handle the flashing and waterproofing detail on new openings, which is where long-term window performance is decided.
Window replacement runs $4,500 to $15,000 depending on the number of openings and access conditions. Impact window installation ranges from $8,000 to $25,000. Related roofing and flashing repair adds $400 to $1,800. Every estimate is free and line-itemed, so you see exactly where the money goes. Call (855) 473-5620 for an exact quote on your project.
Service Areas Near Hillsborough
We serve homeowners across the Peninsula and nearby cities, including ES Windows service in El Granada, ES Windows service in Millbrae, plus Fontana, Bloomington, Rialto, Sunnyslope, Glen Avon, and Muscoy. If you’re outside Hillsborough proper, call us and we’ll confirm coverage for your address.
Book Your ES Windows Service in Hillsborough Today
If it’s not built right the first time, you’re just paying for it twice. That’s been true since I was a boy watching my uncle frame garages in San Bernardino, and it’s the standard we hold on every ES Windows job we take in Hillsborough. Call (855) 473-5620 to schedule your free estimate and get a written line-item quote from Ruben and our crew. We’ll walk your lot, check your openings, and tell you straight what the windows need and what they don’t.
Written by Ruben Castillo, Owner at San Bernardino Contractors, serving Hillsborough and the wider Peninsula with independent ES Windows service, replacement, and new-construction glazing.