Window & door replacement in Portland, OR.
Milgard and Simonton windows and doors, measured, sealed, and finished for the kind of efficiency you feel all winter.
What's included in a Cornerstone install?
The right windows change everything. They frame your view of the world, fill your home with natural light, and quietly cut your energy bill year after year. But even the best window fails early if it's set wrong, which is why the install matters more than the sticker on the glass.
- →Exact measurement of every opening before ordering
- →Careful removal with interior and exterior protection
- →Sill preparation, flashing, and low-expansion foam insulation
- →Level, plumb, and square setting, every unit, every time
- →Interior and exterior trim finished to match your home
- →Operation check and walkthrough before we leave
Why Milgard and Simonton?
Cornerstone installs windows and doors from the most trusted names in the industry. Milgard and Simonton, chosen for their beauty, their performance, and the kind of efficiency you feel the first winter you stop hearing your furnace run all day.
Every install is sealed and finished to keep your home dry, your bills low, and your view uncompromised, and every product carries its manufacturer's warranty alongside our workmanship guarantee.
What warranty do I get?
Every window and door we install is backed by the manufacturer's warranty plus our own written workmanship guarantee. If a unit we set ever leaks at the frame, that's on us, and we fix it.
All services →Common window and door questions
Will new windows really lower my energy bills?
Yes, especially in homes still wearing original aluminum-frame windows, which quietly leak heat all winter. Replacement is one of the highest-return projects on the house: quieter rooms, lower bills, and no more condensation on the glass in January. You feel it the first winter the furnace stops running all day.
Which window and door brands do you install?
Milgard and Simonton, chosen for beauty, performance, and the kind of efficiency you feel the first winter you stop hearing your furnace run all day. Every install is measured, sealed, and finished to keep your home dry, your bills low, and your view uncompromised.
What warranty do I get on windows and doors?
Every window and door we install carries its manufacturer's warranty plus our own written workmanship guarantee. If a unit we set ever leaks at the frame, that is on us, and we fix it. We walk you through the coverage before you sign anything.
Ready to talk about your windows & doors project?
Let us walk through your home and lay out the path forward. Free consultation, no obligation.
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