Knowledge · Injection

Strengthening the foundation before you renovate or build up

An extra storey, a heavier roof, a new load-bearing wall or a large opening in a façade: a renovation often puts more weight on the existing foundation. If there is a weak layer underneath, the house may start to settle after the works. That ground can be strengthened beforehand.

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Resin injection along the façade of a house, with lasers on the wall

When should you think about it?

  • Adding a storey
  • A heavier roof, for example tiles or a green roof
  • New load-bearing walls or large openings in a façade
  • An older house on shallow foundations in clay or on fill
  • Old cracks that have stopped, which you do not want to see again

Two ways

Deep Lift (resin)Magnum Push Piers
PrincipleCompacting weak ground under the foundationTransferring the load to bearing ground
DepthDown to about 3.5 m below the foundationDown to the bearing layer, deeper too
WhenThe weak zone is shallowThe bearing layer is deep or the load rises a lot
ExcavationNone, only small drill holesLocal, to about 1 m

Who decides what is needed?

The new loads follow from the plans and calculations of your architect or engineer. We look at the ground and the existing foundation and propose the technique that fits. That way you know in advance what strengthening is needed, not only when new cracks appear.

Why before the works?

While the house is empty or being renovated, we can drill freely along the façade and inside. Repairing afterwards often means damaging new finishes.

With serious damage, have a structural engineer assess the situation. Soiltek is a specialist contractor: we record, measure, propose a technique and carry out the repair, in consultation with your engineer.

What can we do?

Deep Lift

Expanding resin strengthens the ground under the foundation, without digging.

Slab Lift

Sunken concrete floors back to level.

Frequently asked questions

Is injection enough for an extra storey?

That depends on the ground and how much the load rises. For a shallow weak layer injection is often enough; for a large increase or deep soft ground we choose push piers.

Do I have to move out?

No. We drill small holes along or through the foundation and usually work for 1 to 2 days.

Can this be combined with a repair?

Yes. If there are already cracks, we combine strengthening with lifting or stabilising the foundation.

Not sure?

Send us a few photos of the cracks and the surroundings of your house. We will look, with no obligation, at what may be going on.

Report your cracks

Read also: In which soils does resin injection work? · Foundation repair methods compared · An extension or conservatory that is subsiding