Form lumber is a very important part of many construction projects. Whenever foundations are to be poured, the first step is to create a wooden form commensurate with the volume of cement to be poured into the form. This is what’s known as form lumber.

So the main use of form lumber is to form wet cement. However, form lumber is generally used for the foundations of homes and commercial and industrial buildings. In these two cases, form lumber is a necessity. Form lumber is often used to create foundations for sidewalks, outdoor patios, swimming pools and foundations for lawn and garden sheds.

When you think of form lumber, it’s easy to imagine what would happen if wet cement is poured without it. There would simply be no “form.” Form is the keyword to the use of form wood.

The type of wood used for form lumber is interesting. Woods are either hard or soft in density. One important factor in choosing the type of form lumber is the weight of the concrete it has to support. Consider that one square foot of concrete weighs 150 pounds and you see why the form lumber needs to be strong enough to provide optimal support. Basically, it is the square footage multiplied by the amount of wet cement that determines the strength of the form.

Most form lumber is sturdy, durable and rigid so that it will not only support the wet cement but will also withstand temperature changes and a sudden rain event.

How is Form Lumber Used in Construction?

Basically, in construction projects, project engineers design the size, shape and height of the form lumber to be used. Another factor in the sizes and design of form lumber for construction projects is that these are regulated in the U.S. according to FEMA compliance standards for residential and commercial forms.

It is interesting to note the role form lumber plays in preventing structural damage from shifting soil beneath the foundation, earthquakes, sliding and overturning. Thus, construction project engineers are mindful not only of the design but also of the requirements for compliance for safety.


In construction projects form lumber forms the shape of the foundation the wet cement will take as it dries. Construction project managers must ensure all form lumber joints are tight to prevent cement leaking.

Generally, construction projects rely on form lumber that has been treated to prevent cement discoloration. Also, form lumber should not be dry wood since dry wood absorbs moisture and as such would cause wet cement to be absorbed into the wood.

Form lumber as a hardwood should be purchased for several future uses. Used form lumber can be reused up to six times.

Removing the Form

Many disasters are avoided by removing form at the proper time. Note that different cement types dry at different speeds. This assumes that weather has not interfered with the drying process. Should that be the case, the cement and form lumber should be covered to protect it.

Forms for sidewalks are the simplest designs. However, even with simple designs it is important to avoid concrete vibrations and minor overloading.

Large Building Form Systems

For a large building, the form becomes a form “system” that should be carefully designed, built and installed. Building form systems can be more difficult to remove if the basic design engineering has not considered ease of removal once wet cement is dry.

A large industrial building of more than one story also needs a form that will support the weight of multiple stories. These form system designs need to take into consideration not just the overall building safety but also safety of workers installing the building form system.

Soil Structure

One of the reasons a form system for a building may be a safety hazardous is one that project managers are aware of: The structure of the soil beneath the area of the foundation to be poured.

The simplest determination of the quality and strength of the soil is to have soil tested by a licensed soil expert. Not only does this assure the manager the soil is capable of withstanding the weight of a form system and cement, but testing results provide documentation of the quality and strength of the soil from an expert source, should there be a potential future problem with cement cracking or “fissuring.”

Soil test results provide assurance that the form system and cement can be safely installed and soil shifting under normal circumstances will not occur. This is also the reason to know the best type of cement to be used for the specific project.

Inspection of the Form

It’s always a good idea to inspect the form during the drying process. This will show any unleveled areas that can be easily repaired before complete drying has occurred. Also, this is a good time to observe the effects of weather on the form and cement in the event there has been high humidity or extreme heat.

Form Shapes

Today, form systems comprise a variety of shapes given that buildings can now be built in free form. This means a circular shaped building would require a circle form system instead of the standard square or rectangular shape. Our team is able to provide the correct materials for standard to free form building needs.

At Tulsa’s Security Building Services and Supply, we are well known nationally for supplying small or high volume projects. If our customers need it, we provide it.

We assist our customers with choosing wood and lumber that is cost-effective to help keep project budgets in line. With wood and lumber of the highest quality, the savings are built into quality value.

Choose Your Expert

At Tulsa’s Security Building Services and Supply, we provide the best quality lumber, steel and rebar for your construction needs.

As an industry leader with decades of experience, our team is ready to answer any construction project questions you may have whether they are residential, commercial or industrial. For more details or to place an order, get a quote today.

If your company is looking for construction materials, termite pretreat, and building material supply in Tulsa, contact Security Building Services and Building Supply of Tulsa today! Call us at (918) 663-6272 to speak to a qualified lumber expert.

Fore more information on construction materials and building supply in Tulsa, please follow the Security Building Services and Supply blog. You can also find Security Building Services and Building Supply on Facebook.

Need directions? Security Building Supply on Bing!

Security Building Services and Supply - Lumber, Steel and Rebar Supply in Tulsa

Further reading:

Most Common Uses for Lumber in Construction Projects – Building Supply of Tulsa

There are many different types of building materials involved in constructing a house or building. Learn more about Most Common Uses for Lumber in Construction Projects with Security Building Service and Supply of Tulsa.