Steep Slope Doesn't Faze Custom Hillside Home Builder

A hillside home site in Sequim, Wash., with a million-dollar view and a treacherously steep grade scared off a lot of builders, but Estes Builders was not intimidated. This is a company well-known in Sequim for its expertise with challenging sites.

Sequim sits on the north coast of the Olympic Peninsula, 60 miles northwest of Seattle. The half-acre lot in question rests on a hillside overlooking the Strait of Juan de Fuca, which divides the U.S. and Canada. With the Olympic Mountains to the south and the Strait to the north, views get better the higher up a piece of property is located, but the lots become harder to build on. This particular site had changed hands several times because no one could figure out how to get a home on it, says Craig Stevenson, manager of the custom-home division for Estes Builders.

When the owners requested a bid from Estes to build a custom home on their property, Stevenson decided to see what his crew would be dealing with. After an excavator cleared away blackberry bushes and other debris on the site, he started measuring the grade changes and evaluating the difficulty of getting utilities to the property. "Not only was the site completely treed, but it had very rocky soil," he says. "When you get that high up into a mountainside, there's only about two feet of topsoil left on top of the rock."

The grade change from the site's highest point to the lowest point was about 30 feet, the steepest Estes had ever encountered. "The sewer connection was way down the hill, too, so we were faced with the task of digging through the rock and the dirt to get the home's sewer line below the road and to the other side where the stub was located," says Stevenson.

But he could tell the view would be spectacular. The drop is so steep, nothing can ever be built below the house to impede that view. "When you look out the window, the only land you see is farmland in the valley about 1,000 feet below. It gives you the sensation of flying."

Dirty Work

There are considerations with steep sites that don't apply to flat sites, the biggest being erosion and runoff control. "We have to get a land engineer to design a drainage and erosion control plan," Stevenson says. The cost of having the plan drawn up and executed runs between $8,000 and $10,000.

A structural engineer also has to examine the site to ensure that the soil is undisturbed bearing soil rather than fill. "Often, when developers build the roads for hillside communities, they'll push excavated material onto downhill lots to get it out of the way, creating fill zones on those lots," he says. "You really have to watch for that."

As it turned out, a fill zone was discovered on one corner of the site due to an old logging operation. Under the engineer's supervision, an excavator dug out the layer of non-bearing soil, exposing the rock. Footings were then placed into the bearing soil beneath the rock, and a taller foundation wall with additional bracing was built. The cost of the engineer's report, plus the additional work required, came to $5,000.

Stevenson isn't a huge believer in using topographical maps for home design because they aren't that precise: "They give you a quick idea of what's going on at a macro level." Instead, he prefers to get out on the site with his construction and design team and measure the grade for the proposed location of the garage, driveway and basement.

"There are a lot of times when, if you scoot the house over 30 inches, the corner will fall off a big grade change. You have to go into it knowing that this is how big the garage can be, and you'd better not have the basement bigger than this dimension from front to back, because if you go two feet bigger, you'll fall off that grade change — off the cliff, if you will. By taking all those measurements beforehand, you can dodge so many bullets that you actually save the client a lot of money."

Once the preliminary floor plan is completed, the builder stakes out the house at the site to make sure it works. More often than not, it doesn't. "We get to looking at it and realize that we need to make some adjustments. If we can do that early in the design phase, the client is much more understanding and accommodating."

Beefed-Up Foundation

Just as there are specialized trades for plastering or hand-carved wood trim, there are foundation crews who know how to handle sloped lots — and others that don't. "If your foundation guy is only a flat-lot guy, you're not going to make him a sloped-lot guy," says Stevenson.

An experienced sloped-lot foundation crew chief can supply valuable input on blueprints. Stevenson brings him out to the site and shows him the plans. "We adjusted our plan for this site slightly after having that visit with our foundation guy. It saved our client a few thousand dollars and made it easier to keep the job on schedule."

Estes had an engineer design the drainage system that diverts water away from the uphill retaining wall. "You need to keep water pressure and hydraulic pressure from pushing on that wall. We have a lot of drainage and loose rock and drain pipe against it, so when water finally gets to that spot, it drops into a pipe and is whipped out of the way. It doesn't get a chance to push on the house."

A structural engineer also calculated the uplift force on all the walls so that the home could be designed to resist wind pressure and uplift. Extra concrete footings were placed in the center for this purpose.

Because Sequim is in an earthquake zone, all home builders are required by code to add seismic bracing. But in general, houses on sloped lots are no more complicated to frame than houses on flat lots. Once everything else is done — clearing, grading, utilities and foundation — framing is relatively easy, he says.

With extremely steep sites, it's wise to plan on about a month of clearing and site prep before starting the foundation, Stevenson says.

Catch the Sun

Yet another drawback to building on a steep lot in the foothills of the Olympic Mountains is that the mountains block the sun. To bring natural light into the home, Estes designed it with high, south-facing windows and dormer windows framed open into the living space below. Skylights also brighten up the interior.

"As the sun moves across the sky, the south-facing windows catch both the heat and light and drop it into the core of the building," says Stevenson. "So you get a passive solar benefit, and the windows are high up so there are no privacy issues."

The main living areas — master bedroom, living room, kitchen, dining room and media room — are clustered on the first floor for the convenience of the homeowners. The basement has a family room, two bedrooms and a full bath for the couple's visiting children and grandchildren to use. With the exception of the first-floor laundry room and one of the downstairs bedrooms, all living spaces face the views. Decks were built off the dining room and master bedroom to maximize enjoyment of the scenery.

Stevenson estimates that the home cost between $40,000 and $45,000 more than a typical sloped-lot house because of the additional work required.

"Sites like this are hard, no doubt, but we get a real sense of satisfaction turning them into homes that are easy to live in," he says. "It's also a good market niche because there's not a lot of competition. "

Estes builds between 10 and 14 custom homes a year. For the past three years, says Stevenson, over half of those homes have been built on difficult sites, though none were as challenging as this one. "It made us really work and really think."

Due to its reputation as a tough-lot expert, Estes frequently gets referrals from local real-estate agents. "A number of times clients were ready to walk away from a property because they just couldn't envision how to make it work, " Stevenson says. "And the Realtor didn't have the tools to explain how it could be done. So now agents book an appointment for me to talk to the client at the site. I might even take them over to one of our other nearby projects to give them a visual."

The home took seven months to build and was delivered with zero defects.