“Can We Please Have a House Wash Quote?” Here’s What Actually Happens Next

If you manage rentals, you have sent this email. Possibly this week.

RM – House Wash
Can we please have a house wash quote for this property

A reference number and two lines. That’s the whole brief, and it landed in our inbox in August for a managed rental in Carina.

We want to be clear about something before we go any further: there is nothing wrong with that email. You are looking after dozens of properties. You have never stood in the side yard of this one. The owner asked for “a house wash”, so a house wash is what you asked us for. Working out what the place actually needs is our job, not yours.

But here’s the thing about that particular house. The roof was carrying lichen, and no one on your side of the email had any way of knowing.

So this is the whole story of that job, start to finish, dates and all. If you send exterior cleaning requests for a rent roll, it’s worth ten minutes.

First, what kind of house are we dealing with?

We pulled the property record when the enquiry came in:

• Built in 1950. A 75-year-old post-war home.
• Custom Orb roof. The classic corrugated metal profile.
• Rendered sheeting and cladding walls. Panelised, with those vertical joint battens you can see from the street.
• 4 bed, 2 bath, 1 car. 146sqm on a 617sqm block.
• Tenanted, agency managed.

That last combination is doing more work than it looks. A 1950 house with rendered sheeting is nothing like modern brick veneer. Older substrate, panel joints that hold moisture, and 75 Brisbane summers already through it. Whatever we do to that house, the house gets a say in it.

Then Liam went and had a look

He was there on 17 August, before we quoted a dollar. Four things came back with him.

Lichen on the roof

Raised, crusty, grey-green colonies sitting between the ribs of the sheeting, scattered right across the upper roof plane. Down on the lower section there was dark staining and debris built up along the pans near the box gutter.

You could not see a scrap of it from the driveway. That’s the part worth sitting with. The single most important thing about this job was invisible to everyone involved until somebody physically got up there.

Algae on the walls, not dirt

Green streaks running vertically from the roofline down, fanning out under the window sills and tracking along the cladding joints.

The pattern is the tell. It starts high and runs downward, which means water is driving it: moisture shedding off the roof and travelling down the wall. Airborne grime doesn’t behave like that. It settles fairly evenly, all over. Once you’ve seen the difference you’ll start reading walls from the footpath at every inspection, and you won’t be able to stop.

The side courtyard was the worst part of the property

A narrow, shaded corridor between two wall sections. Barely any sun, almost no airflow. If you wanted to design a place for algae to thrive, you’d build that.

Aspect beats age every time. The shaded south side of a house will always be worse than the sunny north side of the same house, same cladding, same year, same everything.

The soffits and patio ceiling had gone grey

Not dirty exactly. Just dulled off. This is the sort of thing that slips past a routine inspection because it happened a fraction at a time over years, and nobody walks in and thinks “the soffits look about 8% worse than 2023”.

Why lichen is the expensive bit

Here’s what we wish every owner understood before they approve a cheap roof quote.

Lichen is alive. It has a root structure that grips into the surface it’s growing on. It is not dirt sitting on top of the roof waiting for someone to knock it off with a wand.

Which means two things.

One: it can’t be washed off. It has to be killed and released. Blast it with high pressure and you’ll shear off the part you can see and leave the roots exactly where they were. It comes back, often inside a season, and your owner has paid twice for one clean.

Two: on a roof this age, high pressure creates the problem the clean was meant to solve. Ageing Custom Orb doesn’t want that kind of force. You risk stripping the coating, you drive water up under the sheet laps against the direction the roof sheds it, and you can disturb the fasteners. Anyone offering to blast lichen off a 75-year-old roof is quietly offering your landlord a repaint bill.

So we soft washed it. Low pressure, and a cleaning solution that does the actual work on the growth. On 1950 rendered sheeting that isn’t a stylistic preference. Force would push water straight into the panel joints. The substrate decides the method, every time.

How it ran, day by day

Eleven days from first enquiry to a finished job. Our favourite detail: the agent rang the morning the quote landed to ask about scheduling, before the owner had even said yes. He wanted to know we could fit it in. The owner accepted that same afternoon.

Roof, walls and soffits, all done in a day. Just under seven hours, one technician, no return trips, no second crew, one entry notice, one interruption to somebody’s Tuesday.

Because we suspect that’s your actual problem, and it isn’t price. It’s the dead air between “the owner approved it” and “someone turned up”, while the tenant follows up and the owner follows up and neither of them is chasing the contractor. They’re chasing you.

The same bloke quoted it and cleaned it

Liam did the site visit on the 17th and the whole job on the 24th.

Sounds like a minor operational detail. It isn’t. It’s the difference between a crew turning up with a scope written by someone who has never seen that courtyard, and a technician who already knows which wall is the bad one, why it’s the bad one, and roughly how long it’s going to take him.

Six things worth knowing before you send the next one

1. “A house wash” is a request, not a scope. Ask us to quote what the property needs and give your owner options to choose from. Much better than going back for a second quote in three months because the roof is still green.
2. Make someone physically look, roof included. The defining feature of this entire job was not visible from the ground.
3. Lichen isn’t dirt. If a quote prices it like dirt, it’ll be cheaper, and it’ll be back.
4. On an older house, the substrate decides the method. 1950 rendered sheeting doesn’t take the same treatment as modern brick veneer, and when someone gets that wrong it becomes the owner’s repair bill, not the cleaner’s.
5. Ask whether the person quoting is the person doing the work. It’s a very revealing question.
6. One trade, one visit, one disruption beats three trades across three days at a tenanted address. Better for the tenant, and better for how many times you have to arrange entry.

On that last one: whoever you send to a tenanted property should know the entry rules and work with your notice rather than around it. The RTA’s factsheet on rules of entry for general tenancies has the current requirements for tradespeople attending a rental.

The questions we get asked most

How much does a house wash cost for a rental in Brisbane?

It depends on the surfaces, the access and what’s growing, which is exactly why a price off a photo is a guess dressed up as a quote. For a real number: this Carina job, roof, walls and soffits on a 146sqm 1950s home, soft washed in one visit, invoiced at $2,696. A walls-only wash on the same house would have cost a fraction of that and delivered a fraction of the result.

Should the roof be in a house wash quote?

Not always. But it should always be assessed. Roof growth is invisible from the ground and it’s the source of most of the streaking you’re looking at on the walls. Clean the walls, ignore the roof, and the walls go again.

Does the tenant need to be home?

Usually not, though entry has to be arranged properly and they need decent warning: windows shut, washing off the line, pets sorted. Fewer visits, fewer of those phone calls for you.

Is soft washing safe on an old rendered house?

It’s the reason we use it. Low pressure plus the right solution won’t force water into panel joints or lift ageing coatings, and it kills the growth at the root instead of shaving the top off it.

How long will it stay clean?

Aspect decides. Shaded, still-air spots like that courtyard come back first. Open sunny elevations hold on far longer. A house like this one usually sits on a one to two year cycle for walls, and longer for the roof.

Send us the address. We’ll work out the scope.

If you look after properties in Carina, Camp Hill, Coorparoo or anywhere across Brisbane’s inner south-east, you don’t need to tell us what the job is. Send the address, we’ll go and look at it properly, and you’ll have options your owner can choose from, usually within a couple of days.

House washing · Roof cleaning · For property managers & agencies · Book a site visit