When deciding on a foundation for your home, there are many things to consider. One of the most common foundations is the slab foundation. A crawl space is another option you have when it comes to building a house. Which one should you choose? We will examine some of the pros and cons of both types in this article!

Slab Foundation Vs Crawl Space

In order to weigh which might be better for your home build, we'll take a look at each one to better understand each one. From there you'll be equipped to talk with your builder to have an educated conversation and get their perspective on the slab foundation vs crawl space options.

What Is A Slab Foundation?

A slab foundation, also known as "slab on grade foundation", is made of solidified concrete that usually measures 4"–6" thick in the center. The concrete slab is frequently positioned on a layer of sand for drainage or cushioning. Crawl spaces are not available in houses built on a slab, and there is no space beneath the floor.

This is the most popular type of foundation construction in warmer places like Florida or California, where ground freezing and thawing are less of a problem and no heat ducting is required beneath the home's floor.

Slab Foundation Cost

Slab foundation costs typically range from $4 to $25 per square foot. This means that for a 2400 square foot home, the price could be as high as $60,000. The price depends on your location, size of your home and lot slope and preparation needed. Check with us here [add link xxxxx] to get a current price for the greater Sacramento area.

Slab Foundation Problems


Upheaval is the opposite of settling. Upheaval can be caused by tree roots, water flow, or other factors, but can cause serious issues for your foundation.

Foundation Cracks

Foundation cracks can be caused by a myriad of factors including settling under the slab, upheaval, tree root interference, and other factors. Whatever the issue, cracks in the foundation could require expensive repairs.


Settling is common in almost every home. It's the natural process of the earth compacting under the weight of the home over the years. Unless the settling is extreme, it usually don't pose a serious problem.

Improper Site Preparation

There can be issues caused to your foundation if the site wasn't properly prepared for the foundation. Using an experienced and reputable builder usually mitigates this problem.

Plumbing Under Slab Foundation

Because there is no crawl space under the home, all of the plumbing is located beneath the slab. Under slab plumbing, sometimes known as concrete slab foundations that encase the home's plumbing lines, may include copper pipes, cast iron pipes, or galvanized steel pipes that are susceptible to deterioration over time.

What this can mean is that if there's ever a leak, it can cause issues for foundation and be very difficult and expensive to repair.

Slab Foundation Pros And Cons

Crawl Space

A crawl space is an area between the ground and the first floor. It's usually 1 to 3 feet tall, just high enough for someone to crawl into - hence the term "crawl space".

Aside from raising your house off the ground, a crawl space is an easy and inconspicuous place to store the internal systems of your house that would otherwise be in a basement, such as air conditioning and heating systems, ductwork, insulation, plumbing, and electrical wiring.

What Is Crawl Space Encapsulation?

Crawl space encapsulation, also known as crawl space sealing or masonry encapsulation, is a building science technique that transforms a damp, unclean, moldy crawl space into a clean, dry area where mold can't grow.

The challenge is that water can seep into the crawl space under the house and sit, creating the perfect place for mold to form. Mold can cause a whole host of health problems, so some prefer crawl space encapsulation to head off this issue.

Negatives To Crawl Space Encapsulation

There are other considerations to understand before encapsulating your crawl space. Talk to your builder about these issues to see what might be required.

  • Crawl space encapsulation can be costly
  • It may require foundation wall insulation
  • Additional maintenance costs
  • Upgrading your HVAC system may be required

Crawl Space Fan 

Some opt for a simpler option to help dry out their crawl space through the use of a crawl space fan.

Crawl Space Sump Pump

Another option to get water out from under your crawl space is to use a crawl space sump pump. This is a good option if you have a substantial amount of water that tends to collect under the house. When the water reaches a certain level, it will trigger the sump pump and the water gets pumped out to a drainage system.


In the end, a recommendation on a slab foundation vs crawl space for your new custom home is typically given by your builder. Different regions and areas tend to have industry standards that are followed. Yet, we trust this article gave you the information needed to talk intelligently with your builder to help feel good about the decision.

Contact Bianchi-Tillett Developers today for a free consultation and get the information you need to understand the building details and process!

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