Orange algae killed at the root, render left intact underneath, and paving left safe underfoot. This page is the long version, covering what grows on a wall, what treating does that washing cannot, what it costs and every town we cover.
Nearly everything people find confusing about render cleaning — including why one quote can be double another — comes back to this.
Force lifts the visible film, the loose grime and the softer growth off the face of the render. The wall looks transformed the same afternoon, and on a sunny elevation with light growth that can be a perfectly reasonable answer. What it cannot do is reach anything living below the surface, and it breaks the colony into fine particles that land on whatever is nearby.
A biocide applied at low pressure and left to soak into the surface layer, where the roots, the spores and the holdfast a lichen puts down actually sit. Nothing is blasted anywhere. Most of the change shows the same day, and because the growth is killed rather than skimmed off, it is also what decides whether you are doing this again next year or in several years.
Six things account for effectively every wall we are called to look at. They can look similar from the road and they want quite different handling, so it is worth knowing which is which before anybody quotes you.
Trentepohlia, and the single most common reason anybody rings us about a wall. It shows as orange to reddish-brown staining, most heavily within a few kilometres of the sea but by no means only there, and it is taken for rust with remarkable consistency. It is an alga carrying a carotenoid pigment, which is why it is orange rather than green, and it responds very well to treatment.
A single-celled film with no thickness to it at all. That flatness is how you tell it from everything else at a glance. It appears first on whichever elevation dries slowest and it is the easiest of the six to clear. Once it builds it holds enough moisture on the wall to give moss and lichen somewhere to start, so catching it early keeps the job small.
Dark streaking and spotting, most often on north-facing render and around anything that drips. It carries a pigment sheath that shrugs off ordinary washing, which is why scrubbing at it disappoints people so reliably. What clears it is a treatment that gets underneath the sheath, rather than more effort applied on top of it.
On walls rather than roofs it goes for the bottom courses, the shaded base and anywhere old lime render or stonework holds damp. It has real depth — you can lift a piece with a finger — and on a period wall it needs treating rather than scraping, because scraping takes the surface with it.
Part algae, part fungus, bonded into masonry by a holdfast that sits below the face of the stone. Nothing brushes it off, and force is the wrong answer: it is the surface that gives way, not the lichen. What works is a treatment given time to soak in, and then a few days while it dies back and loosens.
Not one organism but the residue of years of them, layered with airborne dust and, near a road, traffic film. It reads as a generally tired wall rather than a visibly grown-over one. It also lifts well, and the before-and-after on a stained elevation is the most dramatic change we produce.
Not sure which you have? Send a photograph from the ground and we will name it. You will also hear honestly whether it is far enough along to be worth treating yet.
Six finishes cover almost every house we are called to. Each wants something slightly different, and getting that wrong is how render gets damaged.
Not sure which of these you have? A photograph settles it. We look at walls all week, and it is our end of the job rather than yours.
The method is the same on every job. Which product goes with it depends on the surface and on what you want.
Anything applied to a wall runs down it, so the ground is dealt with before the wall is. Planting at the base is soaked or sheeted before a drop goes on, drainage points are covered, and we keep a wide margin from ponds, wells and open water. Nothing is mixed anywhere on site. Before we leave you are told how long to keep children and pets off the ground underneath, rather than left to wonder. The garden is part of the job, not something that happens to be beside it, and it goes back the way we found it.
Most of the work happens before anything is applied, and the result arrives after we have gone.
One picture of the elevation and an Eircode is usually enough to price a job properly. From it we read the finish, the extent of the growth and roughly how much surface there is. Anything we cannot see, we ask about rather than guess at.
Planting is soaked or sheeted, drains are covered, and only then does anything go on the wall — at low pressure, at a dilution matched to the finish, and with enough dry hours behind it to soak in properly.
Most of the change is there before we leave, and the last of it clears over the following days. You are told what to expect and roughly when, so you know what you are looking at each morning.
Starting figures for each kind of job, taken from work we have actually done across the county.
Every figure here is a starting point, not a price you will be charged. A softwash is priced on what it is being applied to, and smooth render, pebble dash, K-Rend, painted masonry and block paving all behave differently under treatment and take different amounts of time. After the substrate comes area, then how deeply established the growth is, then how we reach it. That is also why we do not quote a rate per square metre. The metre is not the thing that varies. Send a photograph and you get a real figure for your own walls.
Three things, and between them they explain nearly all the difference.
The substrate, before anything else. A textured finish shelters growth deep in the texture and needs the solution to reach in; a polymer render needs the lightest possible touch; painted masonry is handled around protecting the coat. We match the method to the finish, the method decides the hours, and the hours are what you are paying for.
Catch it while the growth is still a flat film and a wall takes a treatment and a rinse. A properly established colony needs a longer dwell time and sometimes a second application. That difference is most of the difference between a low price and a high one, and it is the one thing on this list you control.
How much surface there is, whether it is all workable from ground level, and whether the roof, the gutters or the driveway are going on the same visit. Everything that shares a set-up shares the cost of it, which is why combined jobs come in below the same list booked apart.
Conditions change more across this county than the distances suggest. Each of these has a page of its own about what happens to render there.
Not on the list? We cover the townlands around all of these as well, so send your Eircode or your nearest town and we will tell you straight away whether you are in range.
Both free, and both have talked people out of spending money this year.
What Trentepohlia actually is, why damp render suits it so well, why it is mistaken for rust with such regularity, and what actually shifts it.
The Render Check walks you through what to look for from the ground in about a minute. A fair number of people who run it are told the walls have another season, which is the answer we would rather give.
The same damp that greens a wall feeds the growth that blocks the gutters above it and works on the roof over them. If they go on the same visit, they ride on a set-up already paid for.
The full set. Town pages carry a handful each; this is the lot.
Almost certainly Trentepohlia — a red algae, and the most misidentified thing on Irish houses. It is regularly taken for rust running off something metal, or for a stain in the render itself. It is neither. It is alive, which is exactly why a treatment clears it and scrubbing does not.
A cleaning solution applied at low pressure and left to do the work, instead of force doing it. It kills the algae, moss and lichen where they are living in the surface rather than taking the top off them, so what you are looking at the same day is dead growth rather than growth blown onto the paving next door. That is why the clean holds.
Because washing clears the surface and leaves the organism. Roots and spores bedded into the render are untouched by force, so the wall is re-seeded from its own supply as soon as conditions suit. Treating at the root is what changes the timescale, and it changes it substantially.
To a degree, yes. Force breaks the colony into fine particles and drives them onto whatever is nearby — the next wall, the paving, the boundary. The growth on the elevation you cleaned is gone; a share of it has simply been relocated. A treatment avoids that entirely, because nothing is being blasted anywhere.
It can, and it is the reason we do not use it on walls. Enough force to shift established growth is enough to etch a surface layer, leave wand marks across an elevation and loosen dash from the substrate. Putting a damaged finish right costs a great deal more than the cleaning did.
Yes, and it is the right approach for them. Polymer renders have a working surface layer that sheds water, and force can mark that layer permanently. A low-pressure treatment asks nothing of the finish at all, which is why it suits K-Rend where anything harsher does not.
Render, pebble dash, dry dash, K-Rend, painted masonry, brickwork, blockwork, natural stone, concrete and paving. Entrance walls, gate pillars, patios and driveways all come under it too. Anything fragile or already weathered is looked at properly before treatment rather than after.
Yes. Block paving, concrete, flagstone and natural stone all take a softwash, and the green film that makes paving slippery is exactly the sort of growth a treatment handles well. Driveways price from their length more than anything else, which is why they start higher than a patio.
Yes, and it is one of the most useful things you can do for a paint job. Painting over active growth is a common reason exterior coats fail early, because the organism carries on living underneath and pushes the new paint off the wall. Treating first gives the coat a clean, stable surface to bond to.
Most of it on the day, and the remainder over the following few days as the last of the growth dies back. We tell you in advance roughly where it will get to, so you know on the second morning whether you are looking at progress or at something to ring us about.
It is handled so that it is. Planting along the base of the wall is soaked or covered before anything is applied, drains are protected, and we stay clear of ponds and open water. Before we leave you are told how long to keep children and pets off the ground underneath. Nothing is mixed on site.
Because the metre is not the thing that varies. The same area of smooth render, pebble dash and K-Rend are three different jobs with three different dwell times, and the depth of growth changes it again. A rate per metre would look precise and be misleading.
One photograph and an Eircode turns every starting figure on this page into an actual number.
Phone: 089-949-1525
WhatsApp: Send a couple of photos
Email: info@eireshine.ie
Send the photo and we will price it properly, tell you what it needs and what it does not, and say plainly if it can wait another season. It costs nothing to find out.
A phone photo of the worst elevation is plenty. It does not need to be a good one.
