Can You Just Level Over a Failed Screed? (A Sydney Pro's Answer)

It’s a scenario we see across Sydney, from Northern Beaches renovations to new builds in the West: you’ve pulled up the old flooring, ready for a stunning new timber or tile finish, only to find the concrete screed underneath is a crumbling, cracked, or uneven mess. Your timeline is tight, your budget is stretched, and you think... "Surely I can just pour some levelling compound over this and call it a day?"

As Sydney-based flooring preparation specialists, we hear this question weekly. The temptation to take a shortcut is real. But taking that shortcut on your subfloor is like building a luxury home on a foundation of sand.

So, can you just level over a failed screed? Let's get straight to the answer.

What Exactly is a "Failed Screed"? Before we solve the problem, let's identify it. A "failed screed" isn't just a bit uneven. It's a subfloor that has structurally failed. Signs of this in your NSW property include:

Cracking: Not just fine hairline cracks, but wide, spider-webbing, or deep cracks. Crumbling: The surface is soft, dusty, or breaks away easily when you scrape it with a key. This is often called 'friable'. Delamination: The screed is lifting or "drummy," meaning it's no longer bonded to the concrete slab underneath. Obvious High and Low Spots: Severe dips and humps that will telegraph through any new flooring. The Big Question: Can You Just Level Over It? You’re looking for a simple 'yes' or 'no'. Here’s the professional, no-fluff answer.

The Short (and Risky) Answer Technically, can you? Yes, you can pour a bag of levelling compound over anything.

Should you? Absolutely not.

Think of it like painting over a rusted car panel without treating the rust. It might look good for a week, but the underlying problem will quickly destroy the new finish. The new levelling compound is only as strong as the layer it’s sticking to. If the layer underneath is weak, cracking, or loose, your new, "level" floor will fail, too.

Why Levelling Over a Failed Screed is a Costly Mistake Covering up the problem guarantees one thing: you'll be paying to do this job twice. Here’s what happens:

No Bond: The levelling compound won't properly adhere to a dusty, crumbling, or loose surface. It will peel or lift, taking your new $20,000 timber floor with it. Reflective Cracking: The cracks in the old screed will simply transfer (reflect) up through the new leveller and, eventually, your finished floor. Future Instability: The whole floor system will be unstable, leading to creaking, bouncing, and tile grout cracking. The Pro Solution: How Sydney Experts Tackle a Failed Screed Doing it right isn't just "better"—it's the only way to protect your investment. At Elyment Group, our process for Sydney and NSW clients is meticulous and guarantees a flawless finish.

Step 1: Professional Assessment We don't guess. We inspect the screed to diagnose why it failed. Was it a bad mix? Poor installation? Water damage? This tells us exactly what we're dealing with.

Step 2: Complete Removal This is the non-negotiable step. The failed screed must be removed. We use specialised equipment like floor grinders and jackhammers, combined with dust extraction systems, to safely and cleanly remove all the compromised material right back to the original concrete slab.

Step 3: Subfloor Preparation (The Most Crucial Step) Once back to the base slab, we prepare it. This often involves "diamond grinding" the slab to create a clean, porous surface (a 'mechanical key') that new products can bond to permanently. We also repair any deep cracks or holes in the slab itself.

Step 4: Priming & Re-levelling First, we apply a high-strength epoxy primer. This seals the concrete and acts as a powerful bonding agent. Then, we install a new, high-quality, cement-based self-levelling compound (or a new screed, depending on the height required). This new layer is strong, stable, and perfectly flat—ready to last a lifetime.

Key Takeaways: Don't Cover, Conquer Never level over a screed that is cracked, crumbling, or lifting. The strength of your floor is 100% dependent on the preparation of the subfloor. A "quick fix" will lead to delamination, reflective cracking, and costly re-works. The only professional solution is to remove the failed screed, prepare the concrete slab, and re-level correctly. Don't Risk Your Sydney Property Investment Your new floor is a significant investment. Don't let a hidden subfloor issue turn it into a nightmare. If you're in Sydney or anywhere in NSW and facing an uneven or failed screed, do it right the first time.

The team at Elyment Group specialises in diagnosing and rectifying complex flooring and screed issues. We give you the perfect foundation, so your new floors look amazing and last for decades.

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