Building on a steeply sloped mountain lot is an incredible opportunity to create a custom home with one-of-a-kind views. It comes with a new set of design opportunities and challenges that are important to understand before you start pre-construction planning.
If you’ve fallen in love with a panoramic vista and are dreaming of your custom mountain home, you’ve come to the right place. Before you hire your architect, learn the top design considerations for building a home on steep terrain to avoid budget pitfalls and bring your vision to life.
Table of Contents
- Designing for the “Why”
- Site-Specific Design
- Hardening from Weather and Natural Disasters
- Cost Considerations
- Sloped Site Home Design Takeaways
When building on a slope or steep terrain, begin with the end in mind. In other words, have a clear picture of how you want to live in the home and what your household makeup looks like. This is especially important when building on a sloped lot because it impacts many site and design decisions going forward, which you’ll see in more detail below.
Answering these questions is a good starting point:
- Will this be a full-time residence, part-time residence, or vacation home?
- Do you plan to live in the home during specific seasons?
- How many primary residents will live in the home?
- How many visitors will you host and how often?
- What attributes drew you to this piece of land? (In addition to the incredible view.)
The answers to these questions inform and guide the site plan and ultimately the final home design. For example, sometimes clients come to us with a piece of land that’s been in the family for generations. The property could be part of a larger family plot, or the area could call up a happy memory or event. There’s often a story behind the client’s sloped property, and this narrative influences everything from site planning and parking to the home’s circulation and programming.
One of the first and most important things to consider when building on a mountain (or any sloped site) is access. The home’s location on the site and how to get there from the main access road are critical.
Depending on the lot size and final home location, the driveway could be long and winding or short and steep. Your site’s elevation and driveway grade will determine snow and ice accumulation, and whether a heated driveway may be needed to improve safety.
Ample parking for your family and guests is essential. If you plan to host many family and friends, a garage and the space in front of it are not enough. For example, if your site plan includes an accessory dwelling unit, you will need to provide enough parking space for the anticipated number of people who lodge there at any given time.
The site will need to provide access to utility companies to not only establish the necessary infrastructure but to provide ongoing service and maintenance. Even if you plan to live off the grid, access to systems is important should you need them in the future or plan to sell the home.
Your home’s site plan must also allow for emergency service personnel and vehicles at any time and without obstruction. This includes emergency medical services (ambulance), law enforcement, and fire and rescue.
But before all of the above can happen, a construction logistics plan comes first. Where the building materials and construction equipment are delivered and stored, and how they access the job site must be determined. This is critical for workers’ safety and to keep your project organized, efficient, and on schedule.
At KGA, we prefer to let the terrain guide the architecture and home design so the home looks and feels authentic to the forms and palette of its natural surroundings. Blowing out some rock and earth is usually necessary to build, but we are wary of taking away too much from the original landscape. After all, the topography and scenery were part of what drew you to the site in the first place.
When we parallel the topography as much as possible, it lessens the environmental impact from flying rock, dust and fumes. It also reduces the amount of heavy equipment and labor associated with this type of work, thereby saving project costs.
We can’t talk about site-specific design without talking about the views. The incredible view is often the home’s primary focal point, and you will want to maximize access to it from as much of the home as possible.
Layout and circulation are often the starting points during initial sketches. Circulation refers to how and where the rooms and areas of a home are placed, and how people move through the home to access them. In a home built along a slope, we consider the primary living spaces first. Living rooms, dining room, kitchen, and bedrooms are usually oriented toward the best views. Access to outdoor living areas should also be considered. Their intended use will impact the number of spaces, their location, and their sizes.
Front-of-house design is also important. The facade and entry create a first impression while setting the design tone for the rest of the home. They create a strong sense of arrival and can enhance the home’s circulation toward the home’s rear-facing views.
Homes built in the mountains or on steep sites have a distinct opportunity to harmonize and connect with their natural surroundings, often more so than homes built on flat land. As such, we like to recommend building materials and fixtures that reflect the forms, textures and color palette of the topography and terrain. This extends to both organic and synthetic materials.
Whether you’re building a mountain home in Colorado or a home on sloped terrain elsewhere, you will probably have to contend with stronger and more intense weather conditions. These types of homes are also more vulnerable to natural disasters and emergency situations, which is why extra precautions are necessary for the site plan and home design.
Storms and strong winds will impact exterior materials like roofing, windows, and doors. Special considerations need to be made concerning rainfall as well as snow and ice accumulation.
Sloped sites are often located in fire-risk areas. Depending on the geographic region, the threat of earthquakes may also be a consideration. Your architect should have an understanding of the weather patterns and vulnerabilities of the land and surrounding area, and should harden the site and structure through orientation, access, site prep, and material selection.
Designing and building a custom home brings its own set of fees and cost structure. And when you add another layer of complexity to it, like building on sloped terrain, there are additional factors that affect your final project cost:
Depending on the geographic location and topography of your land, you may need geotechnical analysis and additional structural engineering evaluations. This is in addition to the consultants commonly required during a custom build.
Blasting, demolition of any existing structures, and removal of trees, plants, and debris may be mild or extensive. Excavating, flattening, and grading could also add costs.
You’ll need to factor in fees associated with accessing public utilities. If you will not have access to water and sewer services, you’ll need to add a well and septic system.
Stringent Building Codes
Building on sloped terrain often comes with a stricter set of building codes for erosion control and hardening against weather and natural events. Additionally, if you’re building in an area with architectural guidelines, share them with your architect in the beginning to prevent issues with design review and approvals.
The complexity and structural requirements of your home’s foundation will depend on if your home will be built on the slope or on a flattened section of the property.
To mitigate the threat of erosion and its impacts on your home and property, retaining walls are often necessary. The amount and size vary depending on the land’s topography and where you intend to build, but make room in your budget for them.
Let the land be your guide when designing your custom home on steep terrain. Views and natural surroundings, coupled with your “why,” will inform a bespoke site and home plan that complement your unique preferences. And while there are additional complexities and requirements that come with building on a sloped lot, it will be well worth it when you’re enjoying a drink with your favorite people, watching the sunset from your new home.
Ready to Get Started?
Let’s talk! Tell us more about your project. We respond within 2 business days.