Lanai at the Cove Walkway Replacement in Seaside, Oregon

Location: Seaside, Oregon
Client/Owner: Lanai at the Cove, a motel and condominium building on the Seaside oceanfront
Partners: The owners’ consulting engineer; City of Seaside
Year: 2011, design
Size/scale: About 80 feet of elevated walkway on a three-story wood-framed building, 40 feet on each of the second and third floors
JBE services: Site visit, structural design and calculations, construction drawings for bidding and permit, letter report
Sector: Multifamily & Housing

Three-story oceanfront condominium building in Seaside with open exit walkways on the second and third floors

The challenge

The Lanai at the Cove is a three-story wood-framed motel and condominium building facing the ocean in Seaside. Residents and guests reach the upper units along open walkways on the second and third floors of the east wing. The walkway decking was wood, and it sat exposed to coastal rain and weather. It had started to rot.

These walkways are the way out of the building, so the code holds them to a heavier load than an ordinary deck. A replacement had to last in salt air, carry exit loading, and get water off the walking surface instead of letting it soak in again.

Project photos

What we did

We visited the building in December 2010 and looked at the walkways and the framing below them. Then we designed a more durable replacement: 2-inch galvanized steel form deck with a lightweight concrete topping slab, spanning about 14 feet between the existing pressure-treated wood beams.

We checked the existing 6×10 beams for the weight of the new deck and concrete plus the 100 pounds per square foot live load the code requires for exiting. They were adequate, so the beams could stay and the work could be limited to the walking surface. To deal with the water, we detailed a shallow gutter along the outer edge of the slab, with drain lines through the half wall to downspouts.

We delivered calculations, a letter report and two sheets of construction drawings for the owners to use for contractor bids and the building permit.

The result

The owners received a permit-ready design in February 2011 that replaces rot-prone wood with steel and concrete, keeps the existing beams, and drains the walkways properly.