Limestone driveways and patios: why it needs different treatment to everything else I clean

Driveway and patio cleaning starts from £100. Limestone tends to take a little longer than tougher stone because I keep the pressure down and won’t use anything acid based to speed things up. Size, the amount of algae and whether you want it sealed all change the final figure. The best way to get a real price is to send a few photos on WhatsApp to 07469 539 068. I normally reply within about five minutes. You get 10% off for quoting that way because it saves me driving out to look. If you’d rather talk, ring me on 0151 272 3404 and I’ll go through it with you.

Often, yes, especially if you send a couple of close ups. Take one dry and one after you’ve splashed it with water. Dirt and algae tend to show darker when wet. Etching stays dull and flat because the polish has been eaten off the surface. Rings under plant pots, marks near the barbecue and patches where something was spilled are the usual giveaways. I’ll tell you honestly what I think I’m looking at. If it’s etching, I’ll say so before you book, so you aren’t paying for a clean expecting it to fix something it can’t. Sometimes it’s both, and I’ll explain which parts will improve.

It depends on the size and how much growth there is. Limestone isn’t a job I rush. I keep the pressure sensible and let the treatment do some of the work rather than blasting it off. That means it can take a little longer than the same size patio in granite or porcelain. I’ll give you a rough idea of time when I quote from your photos. If you want it sealed, the slabs have to be completely dry first. In damp weather that often means sealing on a second visit. I’d rather come back than seal wet stone and waste your money.

If the dullness is dirt, it usually comes up lovely. The pale cream and grey tones show through again once the algae and grime are lifted. If the dullness is etching, a clean won’t bring the shine back, because the surface itself has changed. That’s chemical wear rather than dirt, and it’s beyond what a pressure washer can fix. Most patios I see are a mix of both. The dirty areas clean up and the etched patches stay flat. I’ll tell you honestly from your photos what I think yours will look like when it’s done, so you aren’t surprised when it dries.

Sodium hypochlorite for killing algae is fine on limestone. That’s not an acid issue. What you want to avoid is acidic cleaning products, which react with the calcium carbonate in limestone and damage it. That’s why I’m so careful about what goes on it. The trouble is that people grab whatever patio cleaner is on the shelf, and plenty of them are acid based. Some strong rust and cement removers are too. If you’re going to clean it yourself, check the label every time. If it says acid anywhere, keep it well away from your limestone. When in doubt, ask me before you use it.

Often it’s rust rather than algae. Metal garden furniture, plant pot stands and old fixings can leave orange marks as rain runs off them onto the stone. That needs a different approach to a standard algae clean, and it’s a tricky one on limestone. A lot of rust removers are acid based, which is the last thing you want on this stone. So I’ll look at the marks first and tell you honestly what I think can be done before I touch them. Moving metal furniture onto feet or pads is the best way to stop new marks appearing in the first place.

Roughly once a year for most properties. That’s similar to Indian sandstone. Shaded spots and patios under trees may need more frequent attention because algae gets going faster in the damp. Open, sunny patios can sometimes go a bit longer. Keeping on top of it also matters more with limestone than most stone. Leaves and plant matter left to rot on the surface can react with it, so a regular sweep through autumn helps protect it. A sealer makes cleans easier and buys you more time between them. I’ll tell you honestly if yours can wait rather than booking it in early for the sake of it.

It can be, particularly the honed, smooth finishes. Honed limestone has less natural grip than a riven stone, and a film of algae on top makes it far worse. Back doorways, steps and the path to the bins are the spots to watch. Keeping it clean is the main thing you can do. Once the algae is gone, most limestone is safe enough to walk on in the wet. Sweeping regularly helps it stay that way. If you’ve got older family members or kids running about, it’s worth sorting before winter, when the stone stays damp for days. My post on slippery patios in winter has more on that.

Almost always. I run 50 metre hoses from the van, so I can usually get to the back down a side path or through a gate without coming through the house. If the only access is through the house, tell me and I’ll plan round it. I’ll need an outside tap or another water source, and the gate unlocked if you won’t be in. Tell me about your access when you send your photos. Moving plant pots and furniture off the patio before I arrive helps a lot too. It also lets me see if there are any rust or etch marks hiding underneath them.

Yes, the clean itself is fine in winter. I work all year round. The only time I hold off is a hard frost, because water left on the surface can freeze and make it dangerous. Sealing is where the weather matters more. Limestone has to be properly dry for a sealer to soak in, and that’s harder to get in the colder months. So I’ll often clean in winter and come back to seal on a dry spell. If the forecast looks wrong for your day, I’ll tell you and move it. I’d rather wait a week than rush a stone this fussy.