Why Do House Stumps Fail? | Reblocking and Restumping

The main reason why timber house stumps fail is due to rot. But there are many other reasons why stumps fail. Sometimes it’s due to the wood rotting; other times, the ground around the stumps is too muddy or unstable. 

In this post, we’ll talk about why different types of house stumps might fail and what the common materials are.

What causes house stumps to fail? 

Restumping or reblocking is needed when stumps can’t bear the load of the foundations. Stumps can fail to support the foundation for various reasons, including:

  • The stumps have rotted and need to be replaced
  • The ground around the stumps has become unstable 
  • Pests like termites have damaged timber stumps
  • There is a significant water ingress causing subsidence

There are different types of footings and foundations. Timber, concrete, and steel are the three most common types of stumps. They are distinct in nature; hence they have varied reasons for failing to support the ground.

Why timber stumps fail 

Timber stumps can fail for different reasons, including old or rotten timber stumps, moisture, flooding, insects, and shifting soil. Also, stumps will sink over time if they are not set in a solid foundation. In addition, if the ground around the stumps is too soft, they will eventually heave out of the ground.

To avoid rotting, use treated timber when installing. The treatment will help extend your stumps’ life and prevent insect infestation.

Why concrete stumps fail 

When the steel in the stump is exposed to moisture and air, it begins to corrode. The corrosion of the steel causes it to expand and break apart the concrete, known as “spalling.” If this isn’t stopped, it might eventually cause the stump’s structural integrity to fail. 

To prevent concrete stumps from failing, use steel reinforced concrete and install a moisture barrier.

Why steel stumps fail 

Steel stumps are the most durable type of stump, but they can still fail. The main reason for failing the steel stumps is rust. The only surefire way to prevent rust is to go with galvanised steel. Galvanised steel stumps are superior to all other stump materials. Also, it can fail due to poor installation practices, such as not having a raised concrete base around the stump to prevent moisture build up

You can prevent steel stumps from failing by using galvanised steel and ensuring the base of the stump is finished correctly. 

In this article, we’ve discussed why stumps can fail and how to protect them. We recommend consulting a certified restumping consultant to discuss your problem, and they will help you with the best solution. You can also contact us for a free quote.