Portable buildings have become an increasingly popular option for homeowners, business owners, and even schools looking for additional space or temporary structures. One of the key decisions that must be made when choosing a portable building is selecting the right foundation. There are several types of portable building foundations available, each with its own set of pros and cons. In this article, we’ll take a closer look at the various types of foundations and explore the benefits and drawbacks of each.

Slab Foundation

A slab foundation is a type of portable building foundation where a concrete slab is poured on the ground to provide a stable base for the building. Slab foundations are a popular option for portable buildings, including sheds, cabins, and modular homes.

Pros of Slab Foundations


Slab foundations are incredibly durable and can last for decades with proper care and maintenance. They can withstand extreme weather conditions and are resistant to damage from pests and termites.


Compared to other foundation types, slab foundations are relatively affordable. They require less labor and materials, making them a cost-effective option for those on a tight budget.

Cons of Slab Foundations

Site Preparation

Proper site preparation is essential for a slab foundation to be installed correctly. The site needs to be leveled and graded to ensure that the slab is level and even. Any soil or debris must be removed from the site before installation.

Water Drainage

Proper drainage is essential for slab foundations. If the site is not properly graded, water can accumulate on the slab and cause damage to the building.

Runner Foundation

Runner foundation is a type of portable building foundation where wooden beams or runners are laid perpendicular to the length of the building. The runners are then set on concrete blocks or piers to provide support for the portable building.

Pros of Runner Foundations

Easy to Install

Runner foundations are relatively easy to install, making them a popular option for DIY enthusiasts. They require minimal excavation work and can be set up quickly with basic tools.

Flexible Design

The flexibility of the design is a significant advantage of runner foundations making it easy to maintain and clean. They can be adjusted to accommodate uneven terrain and are suitable for different building sizes and shapes.

Proper Ventilation

Runner foundations offer excellent ventilation, which is critical for preventing moisture buildup and mold growth. The space between the runners allows air to circulate, ensuring a dry and healthy living space.

Cons of Runner Foundations

Vulnerability to Pests

The space between the runners can provide a pathway for pests like rodents, termites, and insects. Proper pest control measures must be taken to prevent damage to the building.

Limited Insulation

Runner foundations offer limited insulation, making them less suitable for colder climates. Additional insulation may be required to ensure that the building stays warm in colder months.


Runner foundations require periodic maintenance to ensure that the runners and piers remain level and stable. Any rot or damage to the runners or piers must be addressed promptly to prevent structural issues.

Pier Foundation

A pier foundation is a type of portable building foundation where concrete piers are installed beneath the building to provide support.

Pros of Pier Foundations


Pier foundations offer excellent stability and can withstand high winds and seismic activity. They are suitable for areas with unstable soil conditions or high water tables.

Suitable for Sloped Sites

Pier foundations are suitable for sloped sites and can be adjusted to accommodate uneven terrain. This flexibility allows for more versatile building placement.

Cons of Pier Foundations

Difficulty in Repairs

If any damage occurs to the piers or footings, it can be challenging to repair. Repair work can be expensive and may require the entire foundation to be replaced.

Vulnerability to Moisture

Pier foundations may be more susceptible to moisture buildup and mold growth due to their elevated nature. Proper ventilation and moisture control measures must be taken to prevent damage to the building.

The foundation of a portable building is a critical element that can significantly impact its structural integrity and longevity. Whether you’re looking to install a portable building for residential or commercial purposes, it’s always a good idea to seek expert guidance from a professional building center like Bennett Spring Building Center.

We have the knowledge and experience to help you select the most suitable foundation type and provide quality installation services to ensure your portable building stands firm against any environmental challenges. So, make the right choice by contacting us and experience peace of mind with our reliable services.