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ECO Window Systems Home Additions & ADU: The Woodland Hills Owner’s Guide
Home additions and ADUs built with ECO Window Systems products in Woodland Hills typically run $45,000 – $130,000 depending on size, site work, and finish level. Most homeowners call us when they’re planning to expand and want to know whether their existing ECO windows can carry into the new structure, or when a bump-out ties into old framing and the window openings stop lining up. We stock and install ECO Window Systems-compatible components for additions and ADUs across Woodland Hills, and we’re the crew that tells you straight what the existing windows can and can’t do before you spend a dollar on framing.
Here’s what you need to know before anyone takes a saw to your wall: ECO Window Systems windows used in additions and ADUs have to meet current Title 24 energy code, and older ECO units from past decades may not. That single fact changes the budget faster than anything else on the job. Isaac Pruett has walked enough Woodland Hills additions to know the conversation starts there, not with a brochure.
Which ECO Window Systems Models This Applies To
ECO Window Systems has produced multiple series over the years, and the compatibility picture changes depending on what’s already in your home. Single-hung and horizontal sliders show up most often in original Woodland Hills construction. If you’re adding on, the question is whether your existing ECO frames are the same extrusion profile as current production. Many older ECO units use a shallower frame depth than today’s models, which means new and old windows won’t sit flush in the same wall plane without a trim detail or a frame adapter.
The way to identify what you have: open the sash and look along the inside track. ECO stamps a series code there, usually two letters followed by four digits. If the glass is double-pane, the spacer between the panes will be visible at the edge. Older single-pane ECO units won’t meet current code for a new addition or ADU in California, period. For the OEM versus aftermarket decision on ECO-specific parts such as sash balances, lock sets, and weatherstripping: OEM fits without modification, but lead times run two to four weeks. Quality aftermarket equivalents from our parts bench often fit same-week, and we’ll tell you when that’s the smart money. We also stock parts for KraftMaid, Cambria, and Silestone when a project crosses over into cabinetry and countertops.
Styles & brands we work with
Signs Your ECO Window Systems Home Additions & ADU Is Failing
- Windows that were square are now binding. When an addition settles, the rough opening moves faster than the window can tolerate. A sash that drags on one side is the first sign the framing is transmitting load into the ECO frame.
- Condensation inside the glass, not just on it. That’s a failed seal. The desiccant inside the spacer is spent, and no amount of California sun will clear it. It’s a replace-the-sash situation, not a clean-the-glass one.
- Drywall cracking radiating from window corners. The header is carrying more than it was sized for, usually after an addition changes the load path. This is a structural red flag that needs eyes on it before you hang another sheet of rock.
- Drafts you can feel at the walkthrough. New drywall and paint shouldn’t whistle. If the ECO weatherstripping compressed during construction, the air gap is small but real, and it shows up on the first utility bill.
- Water staining on interior sill corners after rain. Flashing around the new tie-in wasn’t lapped correctly. Water is wicking behind the ECO frame. Left alone, it turns into rot inside six months in Woodland Hills’ winter wet season.
See the difference
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AfterReplacement Cost & What’s Included
For a Woodland Hills home addition built around ECO Window Systems products, the full project range is $45,000 – $130,000. Where you land depends on three things: square footage, whether the addition ties into an existing roof or gets its own, and how much of the existing ECO window inventory can be reused. A detached ADU runs higher, $90,000 – $220,000, because you’re building a kitchen, bath, and separate electrical service from scratch, not borrowing the house’s systems.
Every quote from Mason Remodeling Co Woodland Hills is a written price before any work starts. That means window assemblies, flashing, trim, labor, and disposal are all on the page. You get a written guarantee that runs 365 days from the completion date. If something isn’t right, we fix it at no cost to you. No change orders, no verbal estimates that grow on the final bill. That’s how we’ve done it since 2004.
DIY or Call Us?
There are things you can safely check before calling. Pop the sash out and look at the balance. If the spring in the balance is still under tension and the shoe is intact, the window is fine and your problem is framing. Check the corner welds on the ECO frame for hairline splits. If you see a split, don’t try to seal it yourself; the frame is carrying glass, and a failed weld under wind load is a broken window waiting for a Santa Ana day.
Here’s where DIY goes wrong: homeowners try to shim a window square that’s binding, which just transfers the load somewhere else. Or they reach for spray foam to kill a draft, which expands and bows the ECO frame. Both turn a $600 repair into a $2,500 sash and frame replacement. Call (831) 290-6866 and describe what you’re seeing. We’ll tell you over the phone whether it’s worth a service visit, and what the likely range is before we send anyone out.
FAQs
Fifteen to twenty-five years is realistic for well-installed ECO units in our climate. The heat and UV load in Woodland Hills eats seals and weatherstripping faster than coastal air does. Double-pane seals often fail in the twelve-to-fifteen-year range without shade. Frames themselves can go longer if the flashing was right. Call (831) 290-6866 and we’ll tell you what yours has left in it.
Sometimes. If your ECO units are current double-pane models in good condition, they can often be re-set into a new opening if the rough opening is framed to match. Older single-pane ECO units won’t pass Title 24 for new conditioned space. The honest answer starts with the series code stamped on the track. Estimates are free, and we’ll tell you before you commit.
Most addition window packages take two to five working days once framing is ready and the openings are cut. That covers setting, flashing, and interior trim. Custom-sized ECO units add two to four weeks of lead time, which we order early so windows never hold up drywall. Call (831) 290-6866 to get a schedule in writing.
We keep common ECO-compatible balances, lock sets, roller assemblies, and weatherstripping on the truck for same-day swaps. Full sash replacements and custom frames are factory orders with two-to-four-week lead times. Most Woodland Hills calls are handled from truck stock the first visit. Tell us the series code and we’ll check inventory while you’re on the phone.
Tell me what you need done. I’ll tell you what it takes and what it costs. Then we get to work. Call (831) 290-6866 to schedule your free, written estimate for any ECO Window Systems addition or ADU work in Woodland Hills.
Written by Isaac Pruett, Owner, Mason Remodeling Co – Woodland Hills, CA at Mason Remodeling Co Woodland Hills, serving Woodland Hills and nearby areas.
