Will a house wash kill my plants?

Here's what we do instead of making a promise. Every plant and bed within about 15 feet is soaked with plain water before we start, re-wet during the dwell, flooded after the wall is rinsed, and finished with a neutralizer. Delicate beds — hydrangeas, hostas, roses, anything planted this year — get tarps. What's left after sodium hypochlorite has done its work is mostly salt water, so the flood matters more than anything. This protocol is why the hostas are still there when we leave.

Is the house-wash chemical bleach?

Yes. The active ingredient is sodium hypochlorite — the same chemical as household bleach, bought at pool strength (12%) and diluted through the rig to about 0.75–1% by the time it reaches your siding. It's the industry standard because it kills algae and mildew instead of pushing them around. We don't call it green, and we won't tell you it's harmless; we tell you what it is, how strong it is on your house, and exactly what we do to keep it off your plants.

Can my dog be outside during the wash?

Inside during the wash, please, with the windows closed. Once we've rinsed the walls and flooded the beds, the yard is back to normal for people and paws — the one thing we ask is to keep pets off the wet beds until they've dried, because that's where the runoff went. If your dog needs the yard mid-job, tell us and we'll stop and rinse a path.

Will soft washing damage vinyl, paint or brick?

A soft wash is designed not to. The mix reaches your wall at about 1%, at low pressure, and the rinse is volume from a couple of feet away — nothing touches the siding hard enough to lift a panel, blow out mortar, or drive water behind the wall. Painted wood and stucco get a weaker mix and a test patch first. The damage people picture — scarred vinyl, stripped paint, blown mortar — comes from a pressure washer, which is exactly what we don't use on a house.

Why does some siding look hazy after a wash?

That's oxidation: the chalky, faded layer that sun and years put on old vinyl and paint. Dirt and algae hide it, so a wash reveals it rather than causing it. We look for it on the walk-through and point it out before we start, so nobody is surprised. A soft wash won't remove oxidation — it takes a separate restoration process — and we'd rather tell you that up front than let you wonder why the wall looks clean but dull.

Do you wash houses in the rain?

Light rain, yes — the chemistry doesn't care, and neither does the algae. A downpour is a different story: heavy rain dilutes the mix before it can dwell and can push runoff where we don't want it, so we reschedule rather than wash a house badly. Wind is the bigger issue — gusts carry mist onto cars, windows and plants — and we'll call it for wind before we call it for rain.

Why does the north wall go green first?

Shade and moisture. The north side of a Madison house gets the least sun, so dew and rain sit on the siding longer, and algae and mildew grow wherever a surface stays damp. Trees, a narrow side yard and a neighbor's wall make it worse. It's biology, not a defect in your siding — and it's why a wash that kills the growth lasts longer than one that just rinses it off.

How we do it

How we wash a house without pressure-washing it

Name: The Total Wash Co.
Address: 7610 Welton Dr, Madison, WI, 53719, US
Telephone: (608) 360-5818
Price range: $

Shot on a Dane County job: a wand soft washing a soffit and eave, with the clean line between the washed and unwashed sections one pass apart.

Soft washing a soffit and eave, a clean line between the washed and unwashed sections — The Total Wash Co., Madison WI

How does soft washing work?

Soft washing cleans siding with chemistry, not pressure. We pre-wet plants and cover the HVAC, apply sodium hypochlorite diluted to about 0.75–1% with a surfactant from the bottom up, let it work 5–10 minutes until the algae turns gray, rinse top-down at low pressure, then rinse the plants again and neutralize.

The green on your north wall is algae, and algae doesn't rinse off — it has to be killed. That's why the chemistry matters and the pressure doesn't. I set up every house-wash job myself: where the beds are, where the condenser is, which walls get a test patch. Mason and Chris run the same checklist I do, and the pressure washer stays pointed at concrete.

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Step by step, the way we actually do it

1
Walk the house with you
We walk every wall together and photograph anything that's already there — a loose panel, a chalky patch, a cracked pane — so nobody has to guess later. This is also where we spot the things that change the mix: painted wood, stucco, a cedar accent. If a wall needs a test patch, it gets one now.
2
Close it up
Every window and door gets closed and checked, because a mist of sodium hypochlorite through an open window is a bad afternoon. Outlets, the doorbell and any cameras get taped. If you have pets, this is when they come inside.
Gear: Plant hose, tarps and HVAC covers
3
Soak the plants, cover the HVAC
Every plant and bed within about 15 feet of the wall gets soaked with plain water from a separate hose, so the leaves are already wet and the soil is already full when chemistry shows up. Hydrangeas, hostas, roses and anything planted this year get a tarp. The outdoor condenser gets a cover — sodium hypochlorite corrodes aluminum fins.
Gear: Plant hose, tarps and HVAC covers
4
Draw test
Before the first wall, the injector's draw line goes into a marked bucket and the rig runs for a set time, so we can see exactly how much chemical it pulls. That's how "about 1% on the siding" stays a measurement and not a hope. The remote bypass gets checked at the same time.
Gear: Super Suds Sucker stainless downstream injector Gear: Water Dragon remote downstream bypass (stainless)Chemistry: Sodium hypochlorite 12%Chemistry: Elemonator surfactant
5
Apply from the bottom up
The soap tip lays the mix on at low pressure in a wide fan, starting at the bottom of the wall and working up. Bottom-up matters: chemistry running down a dry wall leaves clean streaks that never blend, and a wet wall underneath means no streaks at all. One wall at a time, never the whole house.
Gear: 8 GPM pressure-washing rig Gear: MTM Hydro SGS28 trigger gun, J-rod wand and 8.0-orifice tips Gear: Buffer tanks — 225 gal (2012 truck) / 250 gal (2020 truck)Chemistry: Sodium hypochlorite at about 0.75–1%Chemistry: Elemonator surfactant
6
Let it dwell — and keep everything wet
The mix sits 5 to 10 minutes on a timer while the algae goes from green to gray. The wall is kept damp so nothing dries on the siding, and the plants below get re-wet during the wait. Dwell is where the work happens; pressure is not a substitute for it.
Gear: Plant hose, tarps and HVAC covers
7
Rinse from the top down
The remote flips the line to plain water and the 40° tip rinses top-down, held a couple of feet off the wall, until the runoff is clear. It's volume doing the work — 8 gallons a minute — not force. Vinyl, brick, fiber cement: the tip never gets close enough to lift a panel or blow out mortar.
Gear: Water Dragon remote downstream bypass (stainless)Gear: MTM Hydro SGS28 trigger gun, J-rod wand and 8.0-orifice tips
8
Flood the beds, then neutralize
Every bed we worked above gets flooded with plain water, then the neutralizer goes on. What's left after sodium hypochlorite has done its job is mostly salt water, and salt in the root zone is what actually hurts plants — so the flush comes first, and the neutralizer finishes it.
Gear: Plant hose, tarps and HVAC coversChemistry: Neutralizer for the plant re-rinse
9
Walk the walls with you
We walk the house again together and take the after photos from the same spots as the before photos. If a wall has oxidation — the chalky haze on old vinyl or paint that a wash reveals rather than causes — we point it out and explain it, because it's the one thing a soft wash can't fix.
10
Flush the rig
Back at the truck the injector and pump get two minutes of clean water. Sodium hypochlorite left in a pump eats the seals, and a rig that's flushed after every job is a rig that runs the same on your house as on the last one.
Gear: 8 GPM pressure-washing rig Gear: Super Suds Sucker stainless downstream injector

What we never do

Never high pressure on siding.
Never top-down application — chemistry on a dry wall streaks.
Never chemical near an uncovered HVAC unit.
Never skip the plant rinse or the neutralizer.
Never SH mixed with anything but water and Elemonator.
Never SH left in the pump.

The gear this takes

8 GPM pressure-washing rigEight gallons a minute is the number that matters, not pressure.Buffer tanks — 225 gal (2012 truck) / 250 gal (2020 truck)Your spigot gives about 3 to 5 gallons a minute.MTM Hydro SGS28 trigger gun, J-rod wand and 8.0-orifice tipsThe tip decides what touches your house.3/8-inch × 200 ft pressure hose on a reelThe truck stays on the street.Water Dragon remote downstream bypass (stainless)When the mix is on your wall and it's time to rinse, we don't walk back to the truck and pull a hose off a jug — we press a button and the line goes to clean water on the spot.Super Suds Sucker stainless downstream injectorIt's the reason the chemical on your siding is about 0.75 to 1%, not 12.Plant hose, tarps and HVAC coversThis is the kit that answers the first question we get: "What about my plants?" Every plant and bed within about 15 feet of a wall gets soaked with plain water before the first spray, re-wet during the dwell, and flooded after the wall is rinsed.PPE — respirator, glasses, gloves, ear protectionIt protects the person spraying chemistry at your house — which also tells you something about the chemistry.SDS binderYou can ask to see the sheet for anything we're about to put on your house, and we'll hand it to you before we start.

What we spray, and how we keep it off your plants

Sodium hypochlorite 12%, diluted to about 0.75–1% on the siding
Elemonator surfactant (the only thing we add to SH)
Neutralizer for the plant re-rinse
F9 BARC for rust or hard-water stains — a separate step, never with SH

Safety on your property

Windows and doors closed and checked before the first spray; pets inside for the wash.
Plants within about 15 feet pre-wet, re-wet during the dwell, flooded after, then neutralized.
HVAC condenser covered; outlets, doorbell and cameras taped.
Techs in P100/OV respirators, Z87.1 glasses and nitrile gloves; the SDS binder is in the cab.
Sodium hypochlorite is mixed with water and Elemonator only — never with an acid or a degreaser.
A pool smell for an hour or so is normal; keep off wet beds until we've rinsed them.