How to Invoice After House Siding Pressure Washing

Short answer: How to invoice after house siding pressure washing: bill the wall area by elevation, not the floor plan. A 40 by 28 ft two-story house with 18 ft average wall height is about 2,448 ft² of wall. Name the method on the line — soft wash, under 500 PSI, with the mix and dwell — because that is what protects you if water shows up behind the siding. Gutter face streaks, oxidation, and window spotting are separate lines, never assumed.

A house wash invoice does two jobs at once. It explains a number, and it is the only written record of how you cleaned somebody’s exterior wall assembly. The second job is the one that matters six weeks later, when a homeowner finds a damp spot in an upstairs closet and starts working backwards through their calendar. Get the method on the paper. The general fields belong in what to include on an invoice; everything below is specific to washing a house.

What has to be on a house wash invoice?

Write it before the ladder goes back on the rack. Each block is either measured, chosen, or something you will want in writing later.

Block	What it reads
Property and elevations	Address, then front, left, rear, right, plus any detached structure
Wall area	Measured ft² of wall, with the convention stated
Substrate	Vinyl, aluminum, fiber cement, wood, stucco, painted brick
Method and pressure	Soft wash, application pressure, downstream or 12V, dwell and rinse
Chemistry	The mix per elevation and any surfactant, named
Protection	Landscape pre-wet and rinse, fixtures and outlets covered, vents
Condition found	Oxidation, chalking, failed caulk, loose panels, rot, open seams
Add-ons	Gutter face brightening, window spotting, screens, soffit detail
Access	Second story, steep grade, gated side yard, hose run distance
Water source	House spigot, well, or tank haul
Photos	Count of before and after frames per elevation, timestamped
Warranty and terms	What is covered, for how long, and payment due on completion

The condition line is the one that saves you. Chalky oxidized vinyl, a panel that was already loose at the J-channel, failed caulk at a window head, a rotten trim board behind the downspout — photograph it and name it on the invoice before you spray anything.

Where does the wall square footage come from?

From the walls, which have nothing to do with the number on the listing. Two conventions work, and either is defensible as long as you use one of them consistently.

Method	How you get it	When to use it
Perimeter × average wall height	Walk or wheel the perimeter, multiply by height including the gable average	Straightforward houses, fastest
Elevation by elevation	Measure each face’s width and height separately, sum them	Split levels, walkouts, additions, wings

For a rectangular 40 by 28 ft house, the perimeter is 136 ft. At a one-story 9 ft wall that is 1,224 ft². The same footprint at two stories with an 18 ft average wall works out to 2,448 ft² — exactly double the wall for the same footprint, which is why “how big is the house” is a question that tells you almost nothing.

Two conventions to fix and never mix on one document: whether you deduct window and door openings (most operators do not, because you still work around and rinse them, and the deduction invites line-by-line argument), and whether gables are estimated as half of width times gable height or absorbed into the average wall height. State your choice in the notes once and the invoice stops being negotiable.

Height changes the price twice. Anything above the first story means extensions, more chemical to reach it, slower work, and a second set of hands on some houses. Bill the second story as its own line rather than hiding it in a per-foot rate.

Which method line has to appear, and why does it matter later?

The one that says soft wash and states the pressure. This is not a formality.

Vinyl and aluminum siding are lapped, not sealed. Water driven upward under a lap, or driven at pressure into a J-channel, a butt seam, a weep hole, or the gap around a light fixture, ends up inside the wall — and it will not be discovered until it stains a ceiling. That is a claim, not a callback. Manufacturers publish cleaning instructions for their products, and exceeding them can void a siding warranty, which is why a written method line is worth more than any verbal reassurance you gave in the driveway.

Substrate decides everything:

Substrate	Method	What the invoice notes
Vinyl	Soft wash, low pressure, applied and rinsed	Oxidation is separate; chalky panels will not come back white
Aluminum	Soft wash, gentle	Chalking is common and is a coating failure, not dirt
Fiber cement, painted	Soft wash, check coating condition first	Failing paint will lift; documented before start
Wood or cedar	Wood cleaner, then brightener, neutralizing rinse	Two chemical steps, so two lines
Stucco and EIFS	Low pressure, no direct injection into cracks	Existing cracks photographed before start
Painted brick or masonry	Low pressure, mortar checked first	Failing mortar joints noted before start

One legal wrinkle attaches to older houses. On housing built before 1978, work that disturbs painted surfaces falls under the EPA’s Renovation, Repair and Painting rule, and some municipalities have their own restrictions on washing painted exteriors of that age. It is one more reason not to put pressure on old painted wood siding, and one more reason the age of the house belongs in your notes.

Which add-ons do customers assume are included?

Four, reliably, and every one of them is separate labor with separate chemistry. Say them out loud during the quote and print them on the invoice whether they were done or declined.

• Gutter face streaking. The black vertical “tiger stripes” on the outside of an aluminum gutter are an oxidized bond that a house wash mix does not touch. Removing them needs a dedicated gutter cleanser applied and agitated by hand, usually foot by foot from a ladder. It is the single most common “you missed a spot” call in this trade, and it is not a miss.
• Oxidation and chalking on old vinyl or aluminum. The surface coating has degraded. Washing removes the organic growth on top and leaves the chalk, and an aggressive rinse on a chalky wall can produce streaks that were not there before. Removal is a separate chemical and a hand process priced per elevation, and on badly failed siding the honest answer is that painting or replacement is the fix.
• Window spotting and screens. A house wash rinses windows; it does not clean them, and hard water or mineral spotting from the rinse is a real outcome on some properties. Removing and rinsing screens is separate handling and separate risk.
• Soffit, eave, and porch ceiling detail. Wasp nests, spider webbing, and mud dauber tubes are hand work under an overhang that a broad application pass will not reach.

Write the declines. “Gutter face brightening quoted and declined” on the invoice is a two-second line that ends the argument before it starts.

What changed between the estimate and the invoice?

House washes drift from the quote in a small number of predictable ways, and each one belongs on the paper as a visible line rather than a silently larger total.

• The rear elevation. Quotes given from the street routinely miss a walkout basement, a deck skirt, a screened porch, or a wing that adds a full elevation of wall.
• The shaded side. North and tree-covered elevations carry far heavier organic growth and need more dwell, more product, and sometimes a second application.
• Oxidation discovered. Chalk shows up when you touch the wall, not from thirty feet away.
• Artillery fungus. Black specks blown up from mulch beds onto lower siding are largely mechanical to remove and often permanent once cured. Count them, price the attempt honestly, and say in writing what the result will be.
• No usable water. Well pressure that will not keep up, or a spigot shut off for the season, means a tank and a fill trip.
• Height and access. A grade that drops away at the back turns a one-story elevation into ladder work.

What warranty language goes on the paper?

Something specific and short, because organic growth comes back and the only question is whether you decided the terms or the customer did.

A house wash removes what is on the surface today. Mildew, algae, and lichen return at a rate set by shade, tree cover, humidity, sprinkler overspray, and which direction the wall faces — the north side of a house under oaks will show growth long before the sunny front does. State a coverage period you can actually stand behind, say plainly that it covers organic regrowth on cleaned surfaces and not oxidation, coating failure, or staining that was documented as pre-existing, and put the same sentence on every invoice you write.

Then add the two disclosures that prevent most disputes: pre-existing damage found and photographed before the work started, and any result you had to limit. “Lower rear siding carries artillery fungus specks from the mulch bed; treated and reduced, not fully removable” is a sentence that costs nothing and buys back every callback you avoid.

What do I show before I ask for the money, and how do I collect?

Walk each elevation with the customer, in the same order you washed them, with your phone in your hand.

Shot	When	Framing
Each elevation, before	Before the first application	Fixed spot per face — corner stake, driveway edge
Each elevation, after	Same spot, same lens, same day	Identical framing so the pair reads as one comparison
Documented damage	Before start, close up	Loose panel, failed caulk, rot, chalk on a gloved hand
Gutter face, before and after	If brightening was bought	Same run of gutter in both frames
Heaviest growth, before and after	Both	Usually the shaded elevation

Then hand over the invoice on the same screen with the payment link as a QR code they scan on the spot. Residential house washes are due on completion — the willingness to pay peaks while the customer is standing in the yard looking at a clean wall, and it does not come back on Thursday. Check whether your state taxes cleaning services before deciding whether the invoice carries a tax line. When they pay at the door, the paid confirmation is a separate document from the bill, which is the distinction covered in invoice vs receipt.

Did my price per square foot hold?

Check it against the clock, not against what somebody posted in a group.

A house wash is mostly setup, protection, application, dwell, and rinse — and on most houses it clears a minimum charge on its own, unlike the single-surface flatwork stops described in how to invoice after driveway pressure washing. The trap here is not the floor; it is the add-on nobody priced. Gutter brightening on 160 linear feet of ladder work can eat the same hour count as the entire wash and get thrown in for free by a contractor who did not write it down.

So build your rate from your own numbers: chemical cost per gallon of mixed product at the strength you actually run, minutes per hundred square feet at first-story and second-story heights measured on your own jobs, and overhead — trailer, machine, tank, insurance, phone — divided across billable hours rather than the hours you are awake. Then add profit as a margin, not a markup. Adding 35 percent to $210 of cost bills $283.50 and keeps $73.50, which is a 26 percent margin, not 35. To hold 35, divide by 0.65 and bill $323. Over a season of house washes that difference is a machine.

Published per-square-foot ranges are a sanity check only. They swing with region, height, growth load, water access, and season, and none of them know what your route costs to run.

What stays in the file?

The invoice with the method and warranty language, the before and after frames for every elevation, the pre-existing damage photos, the chemical receipts, and the miles you towed. The photos are the defense. The receipts and the miles are the deduction, and keeping them straight through a season is the whole point of a contractor receipt organizer.

Keel is an iOS app that runs entirely on the device: no account, no bank connection, no cloud, no login, and an App Store privacy label that reads Data Not Collected. On a house wash that means the invoice is built in the yard while the siding is still dripping — your logo, your numbering, the elevations and wall area you measured, the soft wash method line, the declined gutter brightening, and the payment link as a QR code the customer scans off your screen. Sodium hypochlorite and surfactant receipts get photographed at the supply counter and read on-device by Apple Intelligence. Tows between jobs log as mileage, with the rules in IRS mileage log requirements. The year exports as one file, or as the Accountant Pack: a CSV plus a one-page summary PDF, on an append-only hash-chained ledger. Free is $0 with unlimited invoices, receipts, and mileage. Keel Pro is a one-time $249.99 Lifetime purchase, not a subscription.

Frequently asked questions

How do I measure a house for a siding wash invoice?

Measure the walls, not the floor plan. Walk the perimeter and multiply by the average wall height, or measure each elevation separately on a split level or walkout. A 40 by 28 ft footprint is a 136 ft perimeter, which is roughly 1,224 ft² of wall at one story and about 2,448 ft² at two. State whether openings are deducted and keep that convention on every invoice.

Should the invoice say soft wash instead of pressure washing?

Yes, with the application pressure named. Vinyl and aluminum are lapped rather than sealed, and pressure driven under a lap or into a weep hole puts water inside the wall assembly, which becomes a claim rather than a callback. A written method line also matters because siding manufacturers publish cleaning instructions and exceeding them can void a product warranty.

Does a house wash remove black streaks from the gutters?

No. Those streaks are an oxidized bond on the gutter face, and a house wash mix does not lift them. Removing them requires a dedicated gutter cleanser applied and agitated by hand, usually from a ladder, foot by foot. Quote it separately, put it on the invoice as its own line, and write the decline when the customer passes on it.

What do I tell a customer whose vinyl siding is still chalky?

That the chalk is the coating breaking down, not dirt, and that a wash removes what grows on the surface rather than restoring a failed finish. Oxidation removal is a separate chemical and a hand process priced per elevation, and on badly degraded siding painting or replacement is the honest recommendation. Put the finding on the invoice with a photo taken before you started.

What warranty should I put on a house wash?

A specific, short one you can honor: a stated period covering organic regrowth on the surfaces you cleaned, explicitly excluding oxidation, coating failure, and anything documented as pre-existing. Growth returns fastest on shaded and north-facing elevations, so say that up front. Using identical language on every invoice keeps the terms yours instead of whatever the customer remembers hearing.

Do I charge more for a two-story house wash?

Yes, as its own line rather than buried in the rate. Height adds extensions, more product to reach the wall, slower application, and on some properties a second person. The same footprint at two stories is roughly double the wall area before any of that, which is why quoting from a listing’s square footage rather than from measured wall area is how these jobs go under.

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This article is general information, not professional or tax advice.