Epoxy Injections: What They Are and When to Use Them
If you’ve spotted a crack in your foundation, you’ve probably heard the term “epoxy injection.” It’s not as complicated as it sounds – it’s a liquid resin that you push into a crack, then it hardens into a solid bond. The result is a crack that’s sealed and reinforced, stopping water and soil from getting in.
People usually turn to epoxy when they need a strong, permanent fix. It works best on clean, straight cracks that are not moving any more. If the crack is still shifting, the epoxy won’t hold and you’ll need a different solution, like a carbon fibre strap or a foundation pier.
How Epoxy Injections Fix Cracks
The process starts with cleaning the crack. You remove loose material, dust, and any old filler. Then you drill small holes along the crack at regular intervals – think of them as tiny doors for the resin to flow through. A special pump pushes low‑viscosity epoxy into the crack from the lowest point up to the highest.
Because epoxy is fluid, it spreads into all the gaps and bonds the concrete together. Once it cures – usually a few hours – it becomes as hard as the surrounding concrete. The result is a reinforced joint that can handle the same loads as the rest of the foundation.
Why choose epoxy over other methods? It’s quick, it doesn’t add a lot of weight, and it restores the structural integrity of the slab. It also looks neat – after polishing the surface, the repair is almost invisible.
Do It Yourself or Call a Pro?
DIY epoxy injection kits are on the market, and they’re tempting if you’re handy. The kits include resin, a pump, and the basic tools you need. If the crack is narrow (under 5 mm) and you’re comfortable working at height and with chemicals, you can give it a go.
However, there are a few reasons to call a professional. First, the preparation work is crucial – a missed cleaning step can leave voids that weaken the bond. Second, the injection pressure must be controlled; too much pressure can force epoxy into unwanted areas, while too little leaves gaps. Finally, a certified contractor can test the cure strength and provide a warranty, which is handy if you ever sell the house.
Cost-wise, a DIY kit runs around £50‑£150, while a professional job can cost £300‑£800 depending on the crack length and access difficulty. If you’re on a tight budget, DIY might save money, but factor in the risk of a failed repair.
Bottom line: epoxy injections are a solid choice for non‑moving foundation cracks. Clean the crack, follow the injection steps carefully, and decide whether you feel confident enough for a DIY job. When in doubt, a qualified contractor will give you peace of mind and a lasting fix.
