The key to success in building a house starts with the land. That’s right, before choosing the colors of the paint and the flowers of the garden, you have to start by choosing a suitable foundation that maintains a solid boundary between the house above and the earth below. This foundation will support your home and maintain its structural integrity, if built on suitable terrain, soil and climatic conditions.
When choosing the foundation, multiple factors must be taken into account. For new homebuyers, this process can seem a bit overwhelming. Your builder can help you decide which type of foundation is best for you and your ground conditions, but you’ll find it helpful to come into the conversation with some background knowledge and prior research.
As you work through the reflection phase of your home’s design plans, here are some factors to consider when selecting a foundation that fits your environment, ground conditions, and lifestyle.
Analyze Your Batch
Before deciding on a specific type of foundation, it is essential to examine the terrain.
Type of Soil
Consider hiring an engineer to examine your terrain and determine soil type, compaction, and moisture levels at varying depths. Indications of clay or sandy soil, bedrock, or a high water table may limit your foundation options. In general, if the soil appears loose or soft, it can lean towards a more robust foundation than would be applied to dry, stable soil.
Ideally, you should build your home on a solid, dry surface with little movement, especially if you’re considering a slab foundation. Clay soils and other components that expand and contract with saturation are not a good complement to the low tensile strength of concrete slabs, which can crack or break with the application of a predominant longitudinal force. Soil types that are subject to movement may be more suitable for pile foundations, pillar foundations, or mezzanines that are anchored to a sufficient depth in the stable soil or underlying bedrock.
Grado y Estabilidad del Terreno
Si su terreno tiene una pendiente o desafíos de terreno, considere cómo esto puede encajar con sus planes. Puede optar por un sótano con luz natural o con salida si tiene una pendiente considerable, ya que aplanar el terreno puede resultar un gasto mayor. En el caso de los terrenos con una inclinación mínima, un espacio de arrastre nivelará suficientemente los cimientos mediante la utilización de paredes de diferentes alturas. Este método estabiliza los cimientos de su casa sin tener que ajustar la pendiente.
Niveles Freáticos
Vivir en una zona con un nivel freático alto descartará casi con toda seguridad la opción de un sótano. Construir demasiado cerca del límite entre el suelo saturado y el no saturado -conocido como nivel freático- pondrá su sótano en riesgo de inundación cuando el nivel freático suba y baje. En estas zonas, una cimentación de tipo “crawlspace” o de tipo “slab” puede ser más adecuada.
Clima
Be aware of your area’s propensity for extreme weather. Regions that are often threatened by hurricanes and tropical storms may find a pile foundation useful to decrease flood risk. Flood zones with a lower risk of high tides can take advantage of a pile or jack foundation to reduce the threat of flooding of the home. Areas prone to winter frosts may not be ideal for concrete slab foundations, which can crack if the soil freezes and thaws frequently. Check with your local builder or city government for recommendations based on area conditions.
Freezing Line
Another reason basements are more likely to be built in the northern and Midwestern regions has to do with regional freezing lines. The freezing line is the maximum depth of frozen soil during the winter months. It can vary depending on environmental conditions, such as soil composition, vegetation, and snow cover. Foundations must be built below the freezing line to prevent damage to plumbing systems according to U.S. building codes. This means that colder regions, with deeper and longer freezing lines, tend to have a greater incentive to build basements, since they already excavate the ground. If a few more feet are added to the depth of the project, the cost is comparatively less than that of building a complete basement in areas with warmer climates.
Drainage
Regardless of the area or type of foundation, rain and soil moisture pose a drainage problem. When creating a space under your home, such as a basement or drag space, keep the drainage plan in mind after heavy rain. If not prepared in advance, any tilting or displacement of untreated land can cause water to wash away or flow freely into your space. It is best to prevent this from the beginning by establishing flood protections.
Consult your builder and structural engineer to determine the most suitable irrigation solutions for your plot. In wet areas, you may need to waterproof the basement or drag space. A sump pump can also help protect your basement from flooding. Sealing your access space, insulating the area, and using a dehumidifier can alleviate moisture and water problems.
Location and Accessibility
Where is your lot located? Is it easily accessible by car or truck? Are you near or off the roads? If your construction site is considered remote and difficult for transport vehicles to access, you should consider the method of delivery of your materials to the construction zone. Winding, narrow or non-existent roads can make concrete mixer trucks impassable. Precast concrete slabs that require a crane for installation will also be complicated, if not impossible. Permanent wooden foundations may be the easiest to transport to these remote areas.
Generalized Pest Problems
Pests, including but not limited to ants, grasshoppers, termites, rodents, rabbits, opossums, and other pesky bugs can be invasive on your home site. Be sure to investigate the area to determine which species are highly populated and/or potentially destructive. There can also be seasonal pests, so if you know that certain worms saturate the soil in winter or that termites are prevalent in summer, plan accordingly.
Wooden foundations, even if properly treated, can be susceptible to bugs as chemical treatments wear out over time. To protect the foundation, regular maintenance and treatment program are necessary. Crawl spaces offer warm space for rodent nests, so be sure to seal off the area or protect it with pest control methods before furry friends find their way home.
Consider the Style and Design of Your Home
Think about how your foundation can improve the design of your home. A finished basement adds a stylish living space or a rentable apartment under your home. An unfinished basement could add additional storage, or a basement with exit could be opened to a large outdoor patio to welcome guests. Each type of foundation brings unique opportunities to personalize and increase the value of your home.
Type of House
Before choosing the foundation, consider the type of housing. Think about the overall size and weight distribution. Large ranch-like homes are not ideal for dock foundations, as floor plans tend to extend horizontally. Longer and wider planes may be more suitable for a slab, while small bungalows are suitable for a drag space.
Outer space
Do you have a gorgeous backyard? Consider showing the wonderful character of your piece of land by incorporating its beauty into the design of your home with a daylight or basement “walkout”. If you live in a heavily wooded area, you can choose a wooden base that adapts to the surrounding landscape for a cozy and natural look.
How to be environmentally friendly and energy efficient?
If energy efficiency is a priority for you, consider a wooden foundation or sealed drag space. The wooden foundations are an ecological option that lightens the space to achieve an airy and natural aesthetic. Entrainment spaces contribute to energy efficiency if the area between soil and soil is sealed, properly insulated and maintained with a dehumidifier. This will protect your plumbing and HVAC systems from the elements and general wear and tear over time, helping them last longer and work easier.
Time and Budget
Depending on the type of foundation, labor costs in your area, house size, and design, project costs can vary greatly, from $4k to over $175k. Concrete slabs are the most cost-effective solution, typically under $21k, while finished basements are the most expensive option. However, you may decide that it is worth the investment if you can rent out the living space underground and recoup some of the cost.
In general, the deeper you have to dig, the higher the price. Machinery and labor costs accumulate throughout the project, making quick options like concrete slab or wood an effective option. Any underground challenges, such as a hidden bedrock or excessive moisture, can add to your expense when you consider the time and cost of excavating the rock or waterproofing your basement.
Consider the Purpose of Your Foundation
Take a moment to think about your plans for the foundation of your home.
Access to Public Services
When you see the general plans of the house, think about the layout of its foundation and access areas for plumbing and utilities. Basements and drag spaces can be ideal when you need to fix a pipe or replace the water heater, while concrete slabs often hide access to buried pipes. Consider how your home’s internal structures fit in with your foundation plans to ensure accessibility before it costs to assemble it in the future.
Storage
If you want extra space to store tools, outdoor supplies, seasonal decorations, maybe a kayak or two, then you might consider the benefits of an unfinished basement or foundation with drag space. The slabs do not offer additional space under your house. If you are looking for a simple storage solution only, you can save money by choosing to leave part or all of the basement unfinished.
Additional Living Space
Consider the possibilities of a finished basement to design additional living areas, such as a suite for the in-laws or a family room. You can increase the value of your home by installing temperature checks and turning the underground part of the house into an additional luxurious suite for family members or guests. If you decide to rent the living space, a basement with its own front door separate from the main house can be beneficial for your guests.
Choose the Foundation Well
If you can choose a foundation that fits your ground conditions, your home design, and your lifestyle, it will set you up for long-term success and protect your structure from future repairs and renovations. I hope this article gives you a starting point for finding the right foundation to meet your needs.