Saint Bernard stain removal on slate tiles

Drool plus urine on slate is a tough combination — the proteins in both bond into the stone's surface texture and the smell compounds quickly, especially in a large area. The only products that permanently eliminate those odours are enzyme-based cleaners; anything else just masks the smell, which means your Saint Bernard will keep returning to the same spots. To point you to exactly the right thing: is the staining fresh or has it been sitting for a while, and roughly how large an area are we talking?

That's a decent area with set-in contamination, so you need something that works at volume without damaging the slate. Before I give you my recommendation — is the slate sealed or unsealed? Unsealed slate is porous and has absorbed urine deeper into the stone, which changes how you need to apply the product.

Good, that actually helps you here. Sealed slate means the urine and drool contamination is sitting at the surface and in the grout lines rather than deep in the stone itself, so an enzyme cleaner can get to it properly. For a job this size, I'd go with Simple Solution Extreme Pet Stain and Odour Remover — the one-litre or larger format. It's a professional-strength enzyme formula designed specifically for dog urine and organic matter like drool. For set-in stains on hard floors, you soak the area thoroughly, let it dwell for 10 minutes so the enzymes can break down the proteins, then agitate with a stiff brush and mop up. Pay particular attention to grout lines — that's where the smell will persist longest if you don't work it in. One litre will cover your 4 square metres comfortably with enough for a second pass if needed.

Probably not on the first go if it's genuinely weeks of build-up — be realistic about that. Do one thorough treatment, let the floor dry completely, then do a smell test 24 hours later. Saint Bernards have a strong enough nose that if he's still sniffing and returning to the same spots, there's residual odour you haven't hit yet. A second pass on those specific areas usually finishes the job. The key mistake people make is wiping it up too quickly — the enzymes need contact time to work, so resist the urge to mop it off after two minutes.

Yes — don't use bleach or any acidic cleaner like vinegar anywhere near slate, sealed or not. Bleach will kill the enzymes if you've applied Simple Solution and then follow up with it, making the whole treatment pointless. Vinegar is acidic and will etch the sealant over time. Stick to the enzyme cleaner, let it do its job, and once the smell is fully gone you can go back to your normal floor cleaner for routine maintenance.