Building a home on a hillside lot can have several benefits but is often not without its own, unique difficulties. In addition to more common challenges like finding a builder and securing financing, building on a steep slope can be complicated by factors like zoning requirements, geotechnical conditions, and questions around affordability. To help individuals overcome these obstacles and take advantage of their unique building parcel, we have created a guide to assessing the buildability of a steep hillside lot for a prefab home.

As part of our series on evaluating land for a new prefab home, we spoke with architect Toby Long on the main things buyers should look out for when assessing hillside lots and their suitability for prefab construction. In our conversation, we break down the unique infrastructure requirements and zoning that often affects heavily sloped lots. That way, you can quickly and confidently decide if a new listing is a bargain or is too good to be true.

Continue reading below as we assess a hillside lot using our land evaluation checklist. As we go through our due diligence, we have also included notes below on questions buyers in similar situations should ask themselves. That way, you can fully understand whether your lot is a good fit or not.

Assessing a Steep Hillside Lot for a New Prefab Home

Notes & Take-Aways

Lot Information: 7042 Westmoorland Drive, Berkeley, CA 94705

What can we infer from the land’s price?

Buildable land is often priced around 20% - 30% of the price of what a completed home on that lot could sell for. A lot valued at $10,000 in an area with multi-million dollar homes, for example, is reason for concern and an indication that there is something amiss with the lot. For this particular lot, however, the land is priced in a normal range for a buildable property in this area.

What does site access look like? How can you begin to evaluate a lot’s access?

One of the biggest questions with this lot (and many hillside lots, particularly in hillside areas of the San Francisco Bay Area or Los Angeles) relates to site access. Can all of the necessary equipment make it to the final build site? As Toby says,

Getting to this particular site up in the hills is not that easy. There's a lot of tight, windy roads that lead us up to the site. There are multiple ways to get to this property, so this would be something where we might start a haul route investigation. And in the work that you and I do, we know there's different ways to do that, from crane people, to transport folks to pilot car companies that actually do route haul observations, to just general contractors that are associated with the staging and delivery of the building.

Depending on the answers from these stakeholders, there are a few possible outcomes - there are no issues regarding access, the access might not be insufficient for modular but acceptable for other prefab building techniques, or the site is not accessible for any type of prefab construction.

What do site conditions look like?

The obvious challenge with this lot is related to the slope of the land. Additionally, there could be challenges with geotechnical and soil conditions that could require advanced engineering and a costly foundation system, which is not uncommon for some areas of California. To finally determine the geotechnical conditions, further investigation is required.

What are regulatory conditions like in the area?

While this question is standard when assessing any lot, in this particular case, we know that there are strict building regulations in the area. In particular, the Oakland Hills and the Berkeley Hills zoning controls are rigid because of various envelope requirements for heights, setbacks, et cetera. On the other hand, as slopes get steeper, there's a relief from some of those requirements, particularly about how far off the road you need to go.

What does the lot’s infrastructure look like?

Looking at the lot elevations, we can see that the realtor already identified utility conditions. And with other homes in the neighboring area, it does not initially seem as though there would be many big problems associated with infrastructure.

Final Verdict

While it is possible that this is a buildable lot, further research is required. Specifically, it is worth checking with the builder, crane company, or pilot car company to determine if the site can be accessed for delivery. From there, the site’s geotechnical condition would be the next step in determining this lot’s suitability. If you would like assistance evaluating land for your own project, connect with a member of our Prefab Coaching program.

Once you have selected a piece of land for your project, you might also be interested in our articles on: