Whether you are buying or building a house from scratch, the foundation will always be a major point of interest and concern. After all, the foundation supports the entire structure, which means it must be very strong and reliable, serving you long.
This is why people often ask what material is most beneficial for their home foundation, concrete or wood, and express concerns about an existing foundation if it is made of wood. To most of them, wood seems to be a rather weak material, so they feel uncertain about using it for the foundation of their future home. This is why we suggest you read this article and break down the pros and cons of these materials.
You are going to find out more about the benefits of a pressure-treated wood foundation, as well as its strong and weak sides. In addition, you will learn more about this type of foundation in general, as well as some specifics it comes with. Also, we will compare wooden foundations to concrete home foundations. Like that, you will be able to see the difference better and clearer. As a result, you will have a clearer vision of the situation, understanding what type of foundation might be the best option for you.
Does It Make Sense to Buy Or Build a House With Wooden Foundation?
Before we figure out whether it makes sense to buy a house that has a wooden foundation or to start building one, we should figure out what this type of foundation is. So what is a wood foundation?
The wood foundation is one of the five types of foundations that are commonly used in the United States. Wood foundations have been built for hundreds of years!
But in the middle of the 20th century, however, a new type of wood foundation emerged — the permanent wood foundation or PWF foundation. It uses pressure-treated wood to create foundations that are resistant to both rot and damage from insects.
In order to better understand the wood basement’s pros and cons, we recommend you learn more about this type of house foundation. Though its name might make you believe that the entire foundation is made of wood, this is not like that. In fact, only the below-grade foundation walls of a PWF are made of wood.
The foundation of many structures lies in a concrete slab over crushed rock or gravel. The wood, crucial for a permanent foundation, undergoes pressure treatment, typically with chromate copper arsenate. This ensures resistance against mold, fungus, and rot, while the arsenate wards off pests like ants and termites. However, while treated wood, commonly used outdoors, combats wood degradation from rot or insects, its treatment and application might jeopardize health and the environment. For a holistic Overview of Wood Preservative Chemicals, one must consider both the benefits and risks.
However, making your home’s wooden foundation moisture and pests-resistant is not enough! In addition to moisture and insects, a wood foundation of your house must be able to withstand lateral pressures from the surrounding soil. In addition, it must be able to cope with environmental loads like wind, rain, and snow, which add pressure to the foundation. This is usually simply an engineering problem, with the width and spacing of framing members determined by the backfill height.
But even if your wooden foundation is strong enough and can bear the weight of the entire construction, there is still one nuance that you should take care of. While treated lumber is resistant to moisture, it is still necessary to waterproof the foundation. For that purpose, you can make use of film, fluid-applied sealants, caulking, and other materials to create a moisture-proof seal. Also, make sure your foundation has proper drainage. Any fasteners that are used in a permanent wood foundation also need to be waterproof.
So in general, you can see that a permanent wood foundation (PWF) has its strong and weak sides. Nevertheless, we can’t say that treated wood should not be used as a material for home foundation! It can also last pretty long and be efficient. You just need to prepare the material properly. Anyway, even though using pressure-treated wood for your home’s foundation is acceptable when building or buying a house, we still suggest you learn about the pros and cons of this material in detail.
Disadvantages Of Wood Foundations
When you have a permanent wood foundation, it may result in certain problems that will have to be handled as soon as possible. And it is good to know what issues you might face in advance! Like that, you can decide whether or not this foundation material could be a good choice for your project.
- It is prone to damage from rot and insects. This is why you have to use pressure-treated wood to avoid that problem
- If a wood foundation is properly built and the site is well-drained, a PWF can last for decades. However, if moisture seeps in or the insect resistance of treated wood fails, replacing portions of a wood foundation may be expensive!
- Wood foundations are generally more expensive to build than those from concrete, or those without basement living space, such as stem wall foundations
- The novelty of this material may cause some trouble for you. In the United States, concrete foundations, whether poured or made of blocks, remain the norm. So if you have a PWF, you may face some additional hurdles — such as when getting the home insured
- The chemicals used to pressure treat the wood used in PWFs require the use of protective gear during construction. And many homeowners are concerned about possible health and environmental dangers
However, despite these issues and downsides, house foundations made of treated wood still have irresistible perks that should also be taken into consideration.
Benefits Of Getting a Pressure Treated Wood Foundation
If you are building a house and you consider using pressure-treated wood as a material for your house’s foundation, it will be good for you to know what benefits you are going to get in this case. Though they remain relatively uncommon, permanent wood foundations have advantages that make them an option worth considering.
- It is easy to install. The same crew that is erecting a house’s wood framing can build wood foundations, and in far less time than it takes to build a concrete foundation
- Permanent wood foundations are well suited for hard-to-reach building sites where transporting materials for a poured concrete or concrete block foundation may be impossible
- It can be erected anytime. While it is more difficult to pour a concrete foundation in wet or cold months, it is easy to erect a permanent wood foundation in any season
- It is easier to move a wooden foundation wall than a concrete one if, after construction, the owner decides to alter the house’s floor plan
- Plumbing and electrical repairs are easier. If you need to access wiring or a pipe, a wooden foundation offers less of an obstacle than a concrete one
- A wooden foundation is a green choice. Since permanent wooden foundations use a renewable resource—wood—they are arguably greener than concrete foundations
- It is insulation beneficial. Another green advantage of a wood foundation is that it creates a warmer basement, lowering heating costs
Like this, now you know more about both pros and cons of wooden foundations. As you can see now, it does make sense to use treated wood as a material for your home foundation, however, it will require additional treatment in order to extend its lifespan and enhance its properties. Nevertheless, wood is definitely worth considering! But why does concrete remain so popular then, you may wonder? Let’s try to figure this out.
Wood Foundation vs Concrete Foundation
Regardless of whether a foundation is made of wood or concrete, it is extremely important to arrange the surface drainage so that it discharges away from the house. This means rearranging downspouts from roof gutters to discharge at least 6 feet away from the foundation wall, and arranging the ground around the home to slope down at least one inch per foot for 6 feet in distance. This prevents excessive hydrostatic pressure exerted on the wall from heavy soils saturated with water, and frost pressure when that saturated soil freezes.
But despite this common requirement, wooden and concrete foundations do have certain distinctions that one should be aware of before deciding which material to choose. Below, you can find a more detailed description of each material.
Poured Concrete Foundation
A poured concrete foundation is made of a solid concrete wall. Around two-thirds of all foundations are made of poured concrete, which makes it the most popular choice. The reason is simple:
- Concrete is durable for use below ground
- Concrete is readily available, which makes it affordable.
In new construction, it is a common practice to reinforce poured concrete with steel rods to add density and strength to the material, however, this also increases the cost.
Poured concrete walls are usually prone to cracking, but on the other hand, they generally resist water quite effectively, especially when a water-proofing membrane is applied during construction.
Concrete Block Foundation
Compared to poured concrete foundations, concrete block walls require more time and labor to install since these walls need mortar at all joints connecting the blocks. These concrete blocks create a hollow core inside the wall that is filled with concrete and reinforced with steel rods afterward.
However, despite the reinforcement, concrete block walls are more susceptible to water intrusion than solid concrete since they have many joints. It is even common for the houses built prior to 1965 to be very susceptible to structural movement and water intrusion since they are mostly made of concrete blocks.
Wood foundations are built with wood that has been treated to resist rot, moisture, insects, etc. These foundations create a warmer basement in cold weather and may be more cost-effective for isolated building sites where concrete is unavailable or would be too expensive to transport.
However, wood in contact with soil is never a great idea. See, when poor surface drainage causes damage to a concrete foundation, it might result in cracking. But those cracks can usually be patched. But moisture damage caused o a wood foundation means rot damage! And once there is rot, it will start spreading.
This is why, if you plan to build or buy a house with a wood foundation, it is extremely important to control surface drainage! Make sure that water is not discharging anywhere near the foundation wall. If you are buying a house with a wood foundation, you should have it analyzed by a structural engineer to determine the estimated remaining service life. And if there are any surface drainage issues, make sure they are corrected immediately.
Well, this is all you should know about wooden foundations and their specifics. You have learned what treated wood foundations are, what makes them different from other types of foundations, especially those made of concrete, and many more. We also explained to you all pros and cons of treated wood foundations so that you could better understand their specifics and nuances of use. With all that, it will be easier for you to decide what type of foundation material you need to buy or build a house.
- Foundation (engineering) : https://en.wikipedia.org/wiki/Foundation_(engineering)
- Foundation Types in Construction: Definition and 5 Primary Types : https://www.indeed.com/career-advice/career-development/foundations-types
- Permanent Wood Foundations : https://www.nachi.org/permanent-wood-foundations.htm
Here are some fascinating facts regarding the topic of buying a house with a wood foundation:
- Wood Foundations are Older than You Think: The concept of using wood for house foundations is ancient. Archeologists have found remnants of wooden foundation piles in structures that are thousands of years old.
- Unusual Geography: In some parts of the world, especially in areas with sandy or soft soil, houses have traditionally been built with wooden pile foundations. In Venice, Italy, for example, the iconic city was built on a series of wooden piles driven into the marshy ground.
- Durability Matters: Some of the oldest wooden foundations still in existence are made from very durable wood species, like cedar and oak, which have naturally rot-resistant properties.
- Technology Advancement: Modern wood foundations, known as Permanent Wood Foundations (PWF), have been in use since the late 1960s. They are constructed with pressure-treated wood, designed to resist decay and pests.
- Environment-Friendly: Wood foundations have a lower carbon footprint compared to concrete. The production of cement (a main component in concrete) accounts for about 8% of global CO2 emissions.
- Insulation: Wood naturally has higher insulation properties than concrete. A wood foundation can help lower heating and cooling costs.
- Repair and Modification Ease: Repairing or modifying a wooden foundation is generally easier and less expensive than a concrete foundation.
Remember, the decision to buy a house with a wood foundation should be based on careful evaluation. Be sure to consult with a professional home inspector to assess the condition of the foundation. They can identify potential issues such as rot, insects, or water damage, helping you make a well-informed decision.
Thousands of years ago, when humanity was transitioning from nomadic to settled life, the choice of building materials was determined by what was readily available. In many parts of the world, wood was abundant. The early settlers found that the wooden foundation piles were not only easy to install, but they were also resilient to various climatic conditions, marking the beginning of the tradition of using wood for foundations.
As societies advanced, so did the techniques for using wood in construction. In ancient Venice, a city built in the midst of a lagoon, the builders faced the unique challenge of creating stable foundations on marshy land. The solution was wooden piles. These piles, driven deep into the marshy soil, formed the foundations upon which the iconic city was built. Despite being in constant contact with water, the piles have remained remarkably intact because the anaerobic conditions of the lagoon floor prevent the wood from rotting.
The use of wood foundations was not limited to ancient societies. With the advent of pressure-treated wood in the late 1960s, the concept of Permanent Wood Foundations (PWF) was introduced. This technology significantly increased the durability and lifespan of wood foundations, making them an attractive alternative to concrete or stone foundations.
However, the question of whether to buy a house with a wood foundation remains relevant even in the modern age. It's a decision that hinges on a multitude of factors - the condition and age of the foundation, the local climate, the kind of wood used, and so on.
The story of wood foundations is a testament to human ingenuity and the remarkable versatility of one of nature's most abundant resources. From the humble dwellings of our distant ancestors to the magnificent structures of Venice, wood foundations have played a critical role in our architectural history. So, should you buy a house with a wood foundation? The answer lies in understanding this rich history and the specific circumstances of the house in question. After all, you're not just buying a house; you're becoming a part of an enduring architectural legacy.
- Consider the Age and Condition of the Foundation: Unlike concrete foundations, wood foundations age differently. While the lifespan of a wood foundation can be impressive, particularly if the wood has been treated properly, it's important to understand that its condition depends largely on maintenance and environmental factors. When considering buying a house with a wood foundation, get a professional home inspection focusing on the condition of the foundation.
- Examine Moisture Levels: Wood is organic and therefore more prone to damage from moisture and pests. Ensure that the foundation is well-protected from these elements. A well-designed wood foundation should have an effective drainage system, a vapor barrier, and be constructed of pressure-treated wood resistant to decay and insects.
- Check for Rot and Pests: Wood foundations can be susceptible to rot and pests such as termites. Inspect the foundation for any signs of these problems. A professional pest control service can perform an inspection and offer advice if there's a problem.
- Local Climate Matters: Wood foundations can perform well in a variety of climates, but they may not be suitable for areas with very high moisture levels, excessive rain, or a high risk of flooding.
- Know the Local Building Codes: Some areas have strict building codes that may limit or prohibit the use of wood foundations. Before purchasing, make sure the house is up to code, or you may face issues if you decide to remodel or sell in the future.
- Insurance Implications: Some insurance companies may charge higher premiums for houses with wood foundations due to the perceived increased risk of damage. Check with your insurance provider before purchasing.
- Remember, every house and situation is unique. These tips are general advice and may not apply to all situations. Always consult with professionals when making significant decisions about real estate.
Should you buy a house with a wood foundation? If the condition is good and all other factors are favorable, why not? You might be adding a chapter to the history of wood foundations!
Frequently Asked Questions
How Long Does A Wood Foundation Last?
How Much Does A Wood Foundation Cost?
Are Wood Foundations Common In Residential Construction?
Wood foundations, specifically pressure-treated wood, are relatively uncommon in residential construction compared to concrete and masonry foundations.
What Are The Advantages Of A Wood Foundation?
Advantages of wood foundations include ease of installation, lower cost, good thermal insulation, and resistance to cracking or settling.