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New Zealand
Many residential areas in New Zealand are built on low lying flood plains, making voiding underneath houses, driveways, or surrounding areas a common problem for homeowners.
There are many reasons you might be experiencing voids. Some soils are more reactive, and can expand or contract throughout the year. Extreme weather, poor drainage under your house, or even unruly tree roots can make this worse. House extensions could be putting too much pressure on your foundation, or vibrations from nearby construction works could be causing changes in the ground.
Whatever the reason, if left untreated, these voids can cause further structural damage over time. Fortunately, there are several options for treating these voids that are quick and minimally disruptive.
Read on to find out what signs to look for, as well as what preventative actions you can take. If you are already dealing with voids on your property, we also have a few options for repair work.
What signs to look for
Homeowners may notice visible gaps or voids forming underneath their house or elsewhere on the property. These voids typically form due to ground settlement or a wash out from heavy rain. Make sure to check the entire perimeter of the slab.
Here, the ground has clearly sunk away from the house and driveway slab
If voids are not visible, there are a few other signs that could indicate voiding under a concrete slab:
- Drum-like or hollow sound when knocking or stomping on the slab
- Buckling or bowing of the floor inside the house
- Sloping or uneven floors
- Cracking in the concrete slab
Homeowners should also look out for cracks in their walls, windows jamming, or doors that won’t close properly because of settlement. Visible cracks, especially those that appear suddenly or get bigger over time, can indicate voids beneath the slab. Another sign is gaps where your walls meet the floor, which could indicate a sinking or damaged foundation.
If voiding is left untreated, further stress on structural elements such as slabs, walls, windows and doors will cause more damage over time. A compromised slab can also be dangerous, posing risks to everyone living in the property.
Gaps and voids can let pests in, leading to infestations, and the overall structural issues will also reduce the market value of a home.
Preventative measures
There are precautions that homeowners can take to prevent the formation of voids.
- Proper Site Preparation and Soil Compaction: Make sure the soil is compacted properly before pouring the slab.
- Effective Drainage Systems: Install and maintain good drainage around the home to prevent soil erosion.
- Regular Inspections and Maintenance: Have a professional inspect the area periodically to catch early signs of voiding.
- Use of Geotechnical Engineering Solutions: Get soil support specialists to densify the soils.
- Removal of Trees and Irrigation: Removal of trees and irrigation systems close to the slab can reduce the effect on the soils around the property.
What to do if you already have a void
There are several options for void filling on the market. At Mainmark, we prioritise cost-effective methods with minimal disruption, noise and mess. Unlike other systems that require the use of jacks and heavy machinery dragged through the property, Mainmark’s Teretek resin injection and Terefil solution is non-invasive.
Our engineered products are suitable for a variety of void filling applications, and we select materials based on void size, location, and site-specific requirements.
Fixing voids beneath your home is possible with the right expertise. Acting early will prevent further damage and more expensive repairs in the long run.
A chat with an expert can give you a better understanding of the cost involved, including in the long term.
Get in touch with the team to learn more.
