What happens when a Saul Zaik–designed home gets a glam-infused glow-up? Welcome to the Mason House 2.0. The midcentury architect completed it in 1971 for Cecilia and Michael Mason on a 1.88-acre lot in the Cedar Mill area. After the original owners sold it in 2021, the new owner-designer incorporated strategic updates—primarily to the kitchen and bathrooms—for more modern living. Nary a window, wall, or wood-clad ceiling was eliminated, so the Northwest Modern bones persevere. But there are now custom built-ins, designer wallpaper, and an artist-commissioned light over the dining table, as well as a truly gorgeous kitchen.

The house sits at the end of a winding drive, presenting two stepped volumes connected by a glassed-in breezeway at the entry. This arrangement creates a cool courtyard effect, so the big windows, from one end of the house to the other, capture views into it or the surrounding forest from multiple angles. Staggered roofs provide deep cover for several porches tucked along the perimeter, just casually doing that whole indoor-outdoor integration thing that Zaik and his cohort were known for.

Inside, it remains the original split-level plan across 4,009 square feet, with the garage and primary suite on the entry level. Down a few steps, find the main living areas, with the kitchen and dining room flanked on either side by living rooms, one a bit more formal than the other.

The proper living room is delightfully sunken down a few more steps, and has a two-story vaulted, wood-clad ceiling. It's hard to say if the window wall or fireplace is the main focal point. The first is original, while custom walnut built-ins bookend a new stone surround at the latter, to make for a cozy spot to sit for a fireside chat.

The overhauled kitchen also keeps to the same footprint as before but is now outfitted with custom walnut cabinetry on all four walls to maximize storage. The fronts are even grain-matched so it looks seamless around the room. The leathered quartzite backsplash, with matching counters, climbs all the way to the ceiling for dramatic effect.

In the attached informal living room, more custom walnut cabinetry and shelving are an ideal staging area for parties, while the built-in window seat, another original feature with new upholstery, is perfect for introverts.

At the bathrooms—five total with two of those being powder rooms—any hint of ’70s-era tile and laminate has been swapped for luxe stone, custom vanities, and walk-in showers. Every bedroom, from the primary suite with its private sitting room to the three bedrooms on the second level, has an airy aspect, thanks to extra-tall vaulted wood-clad ceilings, unexpected angled windows underscoring the roofline (upstairs), and glass doors that open to the yard in the primary. After the makeover, even the gym is a little glam, yet still classic, as a marble slab accents the wall behind the mirror, and clerestory windows reveal nearby tree trunks.

Listing Fast Facts 

• Address: 10950 NW Lost Park Dr, Portland, OR 97229
• Size: 4,009 square feet/4 bedroom/5 bath 
• List Date: 9/16/2026 
• List Price: $3,489,900
• Listing Agent: Marisa Swenson, Modern Homes Collective

Melissa Dalton is a freelance writer who has focused on Pacific Northwest design and lifestyle since 2008. Contact Dalton here. 

Editor’s Note: Portland Monthly’s “Property Watch” column takes a weekly look at an interesting home in Portland’s real estate market (with periodic ventures to the burbs and points beyond, for good measure). Got a home you think would work for this column? Get in touch at [email protected].