The 1994 Northridge quake gained record-breaking ground movements. (1.8 g) This was the largest horizontal peak ground acceleration ever measured
A hillside covered with grass can create a beautiful setting for building your dream house in Texas and California. However, the entire process of turning that dream into a reality is much complicated as compared to building an average dwelling. When you’re constructing your dream house on a slope, you’ll certainly come across various challenges. In this article, we’ll inform you about those challenges to help you avoid a longer construction period and additional costs, especially if your lot is in California.
Methods of building on a slope
Generally, there are 2 ways of constructing a home on slopes. These methods include:
• Using stilts
• Through the ‘cut & fill’ method
Now, let’s have a look at each of these methods!
i. Using stilts
Instead of cutting into a slope, this method involves lifting the house onto supporting steel or wood columns using the crane. This method is more cost-effective as compared to the cut & fill method. Moreover, this method can open up various possibilities of home placement, like building a home over water or tree.
ii. Cut & fill method
This method involves leveling the ground level out, either by removing and/ or adding soil. This simply means that you can cut/ dig soil from a slope or bring soil in for filling your plot and then level it. Based on various factors like the grade and condition of the soil, the cut & fill method can make building your house more costly as compared to building on a flat plot.
Why Build your house on sloping areas?
Most of the world’s most envied homes are constructed on slopes. So, why do people prefer building on slopes? Well, here are some of the reasons:
Landscaping- the main reason why most people enjoy building their homes in the inclined area is the fascinating aesthetics presented by the slope, including the chance to develop a breathtaking landscape.
Natural lighting- Houses built on the hillside are perfectly situated, thus maximizing the amount of natural lighting entering the house. This feature provides several health benefits like higher productivity, better mode, and better sleep.
The views- building on a slope enables you to enjoy the stunning views of wooded forests and green valleys below as well as views of the clear sky above.
The seclusion- if you value your privacy, constructing your home on a sloping area will enable you to choose the most private location.
Space-steep slopes enable you to include a lot of extra space in your house, including a walkout basement which can also be used as another floor.
Challenges of building your house on a slope
The challenges of building a home on a slope are mainly caused by 2 factors, namely, whether the area is downslope or upslope and gradient of your lot.
An upslope lot refers to a slope where the front part of your home will rise towards the back. Building on an upslope is more challenging as compared to building on a downslope lot. Some of these kinds of lots usually involve blasting or cutting, disposing of as well as transporting the soil and rocks.
The gradient rating of a slope determines how challenging building on a particular plot will be. Slopes whose gradient is below 10% are considered slight, hence the simplest to construct your house on. On the other hand, slopes with a gradient above 20% are deemed steep, thus more difficult to build your house on.
With that in mind, let us have a look at some of the challenges of building your house on a slope;
• Extra foundation works-cost and time
Building a house on a slope usually requires a complex foundation system. Such foundation systems are often more costly and take more time than the construction home of a flat plot. This is mainly because building those foundations involves deeper excavation using specialized equipment for excavation or blasting, more concrete, terraces and even retaining walls among others. All the additional materials and labor needed to make sure the house structure is safe and meets all the building codes results in longer construction time and higher costs.
• Water- sewage and drainage
Drainage of both subsurface and surface water is very important when building a home on a sloping area. Rainfall-runoff should be directed away from the foundation of the house without endangering the neighboring properties or public roads with the water flows. Additionally, you should ensure that the retaining walls are waterproof and well-drained.
Sewage treatment may also be another challenge based on the location of your house relative to a sewer line. For instance, if the sewer line is on the upper side of the slope, you’ve to install the pump. On the other hand, if the sewer is downhill, you might be forced to slow down the flow using tumble bays.
• Accessibility to the property
Accessibility to the lot, both for you and the contractor, is a critical factor that should also be put into consideration. If the plot doesn’t have a good way of accessing it, the added costs when building on a slope in Texas and California may even go higher for extra grading. Curved driveways and switchbacks are attractive and helpful when building on a sloping area. However, if the property is small, you might be forced to install steep driveways because of space limitations. This can be very hazardous, especially in harsh weather.
• Staging areas and storing the fill soil
If your land requires cutting, you’ll either have to store or transport the resulting additional soil away. Moreover, you will need an area for staging equipment, deliveries, and vehicles.
• Soil type
Even though the soil type of a sloping properly may be overlooked, it can pose some challenges to the builders. Granular soils have a high load-bearing capacity and drain well. However, that is not the case with clay soils. Clay soils tend to swell and expand when frozen or wet, which can affect and damage the foundation. Furthermore, they might require an extra fill of the granular soils or costly engineering fixes.
Rock ledges that are close to the surfaces also present challenges with septic and drainage systems. Since blasting such rocks is expensive and it might affect the neighboring foundations, the most economical solution would be working around them.