Is Hardwood Floor Expansion Gap Really Necessary? – Understanding How Different Wood types Expand And Contract

Is Hardwood floor expansion gap really necessary?” – Expansion gaps play crucial roles in flooring; without them, wooden floors become prone to instability and damage.

Hardwood floors usually have little gaps that play significant roles in maintaining the integrity and longevity of your wooden floors. 

These engineered woods can retain moisture and react to changes in temperature; this is why an extension gap becomes necessary. 

You might not see it, but it’s silently doing its job. An extension gap is the tiny space left around the floor edges after installing your wooden floor. 

Because your wooden floor can expand or contract due to temperature and moisture changes, extension gaps become necessary to maintain your flooring. 

They can prevent your wooden floor from easily getting damaged. 

In this article, you’ll learn about the types of wood floors and how they expand and contract. 

What Is An Expansion Gap? Why Do We Need It?

A man is fixing hardwood boards to a floorboard.

Solid hardwood floors

An extension gap is a small space deliberately left around the perimeter of a hardwood floor. This space is typically between ¼ to ½ inches wide.

It separates the edge of the floorboards from the walls and other fixed vertical objects in your room.

Some of these objects may include columns, baseboards, thresholds, doorways, hearths, fireplaces, and around pipework. But why is this gap necessary, you may ask?

Hardwood is a natural material, and like all natural materials, it responds to environmental changes. Changes in temperature and humidity within your room can cause wood to expand or contract.

You can think of it as how the wood adapts to its surroundings, just like our body.

That is one of the major reasons hardwood is used for various purposes like creating cutting boards, furniture making, flooring, decking, burning, etc.

Without this gap around it, your hardwood might have several problems. For example, during periods of high humidity, the cells of the hardwood would absorb moisture from the atmosphere and expand.

That expansion could cause the wood to push against your wall and create an unsightly buckling effect you wouldn’t like.

Also, when humidity levels are low or during dry seasons, the hardwood contracts and leaves noticeable gaps between the floorboards.

Now, that’s where the expansion gap comes in. It serves as a practical solution to the problems above. It gives your hardwood floor the space it needs to respond to environmental changes.

In other words, it prevents your floor from developing faults like cupping, warping, or noticeable gaps between the boards. 

Types Of Wood Floors And How They Expand And Contract

In the world of wood flooring, there are two major types of wood floors: solid hardwood and engineered wood. Below, you’ll learn what they are and how these two types of wood floors expand and contract. 

Solid Hardwood floors

Artisans create solid hardwood floors from a single piece of genuine hardwood. Unlike engineered hardwood floors, no extra materials are added to it.

That is one of the reasons people prize them for their natural beauty. They also experience more expansion in the direction of the tongue and across the product’s surface. 

Solid hardwood floors expand and contract more easily than engineered hardwood floors. This shouldn’t be surprising if you consider that engineers built engineered wood floors to solve solid hardwood’s expansion and contraction problem. 

Nevertheless, the rate at which a solid hardwood floor would experience such changes depends greatly on several factors.

Some of these factors include the humidity levels of its environment, the type of hardwood you’re using, and its layout. 

Engineered hardwood floors

Unlike solid hardwood, engineers build engineered wood with multiple layers. The first layer is typically a hardwood veneer, while the lower layers could be either plywood or high-density fibreboard (HDF). In contrast to its counterpart, medium-density fibreboard (MDF), people use HDF for flooring and other applications that demand durability. 

Their creation aimed to prevent undesired expansion and contraction due to changes in the humidity level of their environment. So, if you were to compare them to solid hardwood floors, you would find that they are more stable and don’t easily expand or contract. 

The way they work is that the lower layers restrict the movement of the wood. That process makes it more difficult for your engineered hardwood to expand and contract as it wishes.

A picture of a floorboard with plywood layers

A picture of a floorboard with plywood layers

Regardless of which hardwood you use in your home, ensure you add a proper expansion to it. That would allow your floor space to expand and contract as gracefully as possible without any issues. 

A hardwood floorboard

A hardwood floorboard


In summary, expansion gaps are highly beneficial for your wooden floor. They ensure your floors remain resilient and as beautiful as whu initially got them.

Regardless of the wooden flooring you have installed, ensure you add a proper expansion gap to your hardwood floor to prolong its lifespan.