Cleaning tired walls in South Pool
Creek-head hamlet on the Salcombe estuary.
Where a South Pool wall has gone patchy rather than evenly dirty, the cause is nearly always local: a downpipe, a hedge, a shaded corner. That is where we look first.
South Pool is a creek-head hamlet on the Salcombe estuary, recorded with cob and painted render beneath slate. Because cob relies on a sound protective skin, the survey begins with coating adhesion, cracks, plinth condition and previous repair materials. Creek-side context may affect drying, but it cannot replace inspection of eaves, openings and sheltered wall returns. A test is considered only on intact coating and with restrained wetting. Any exposed cob or unstable finish is excluded and flagged for repair, ensuring the plan protects the wall build-up rather than chasing an immediate colour change.
Working out what is wrong on a South Pool wall
- 01The angle of morning sun on the elevation tells you how long it stays damp.
- 02Whether the property is exposed or sheltered is judged on the day, not from a map.
- 03Where the pattern is even across the whole face, exposure and aspect are the cause.
- 04A slow walk of the gutter line from the ground finds most of the causes worth fixing.
- 05Where the pattern is a band at the top, the gutter line is doing it.
- 06How quickly a splash of water darkens the surface says how porous the finish has become.
- 07A fingernail drawn across the growth says more in a second than a photograph does.
- 08Where a wall meets a roof abutment, the flashing is looked at first.
Material first, method second
- Modern render, whether sand and cement or a thin-coat system, has a slightly porous face that holds airborne spores.
- Patched render takes treatment differently from the original, which is why patches are identified before work starts.
- Painted masonry can be cleaned, though a paint film that has already lost adhesion will lift where it was going to fail anyway.
- Masonry paint over render adds a film that traps moisture if the substrate was damp when it was applied.
- The base of a cob wall is the most vulnerable part and is often left alone entirely.
- The safest outcome on cob is a lighter, slower improvement rather than an immediate transformation.
Why this keeps happening on TQ7 elevations
- Once lichen is established it holds water itself, which makes the surface beneath it wetter than it started.
- Rain running off an unsealed timber fascia carries tannin down the wall as a brown stripe, not growth at all.
- Airflow through a passage between two houses is fast but the passage itself is in permanent shade.
- Salt-laden air roughens exposed surfaces slightly, and rougher surfaces hold more moisture.
- Black spotting on white render is a different organism from the green film beside it, and it clears at a different rate.
- A wall that faces a large expanse of glass on another building gets less sun than its aspect suggests.
- Growth returns fastest where the underlying cause was never dealt with, which is usually water going somewhere it should not.
- The first sign is usually a faint grey cast rather than green, and grey is easier to ignore.
- Where a wall was cleaned without a biocide, the regrowth is often patchier and faster than the original.
On site in South Pool
- 1.A wall with a visible damp patch inside is treated on the dry areas only until the cause is found.
- 2.The job is worked one elevation at a time from end to end so that nothing dries out mid-wall.
- 3.A wall in deep shade is worked earlier in the day, when there is most light on it to judge coverage.
- 4.Where a wall abuts a neighbour's boundary within a metre, the fan is narrowed and the pass slowed.
- 5.The same operator works a whole elevation so the application rate stays consistent across it.
- 6.Downpipe backs and the strip of wall behind them are done by hand, because a sprayed pattern always misses them.
- 7.Beds and borders at the foot of the wall are soaked with clean water first, so any run-off arrives diluted.
- 8.Where a lean-to gutter runs at wall height, it is cleared first so it does not overflow mid-visit.
- 9.Photographs are taken of anything found in poor condition, so it can be shown rather than described.
- 10.Neighbouring cars and windows are checked before spraying starts on a boundary elevation.
Local detail that changes the job
- Recorded character: estuary hamlet. Creek-head hamlet on the Salcombe estuary.
- Nearest full coverage hub: Salcombe (TQ8), South Hams District Council.
- Access is usually via A381.
- Salcombe sits about 3.5 miles from South Pool on our round, so visits are often shared.
- Typical wall finish here is cob and painted render, which sets the cleaning method.
Preparing a estuary hamlet property
- If a security light or camera covers the elevation, tell us so it can be isolated.
- Note where hoses can be run without crossing a doorway.
- Note where the electricity meter and consumer unit sit relative to the wall.
- Tell us if a fence panel is loose, because sheeting gets pegged to something solid.
- If you have a pond, a water butt or a wildlife area, point it out in advance.
- Mention any cladding or timber detail that you would rather was left alone.
- Point out any window that does not seal properly, so it gets sheeted rather than sprayed near.
- Say whether the property is occupied during the day, since that changes nothing technically but helps the plan.
What to book before and after the walls
If windows were cleaned recently, tell us, and they get sheeted rather than redone.
Where gutters need repair rather than clearing, that goes ahead of any cleaning at all.
If a decorator is due, the wall clean goes in first and is given time to dry fully.
Gutters are cleared between the roof and the walls, so the first heavy rain does not restain a finished elevation.
Practical questions answered
- Can you work while builders are on site?
- Better after they finish, so their dust and debris does not land on clean work.
- Can you treat a wall that has already been jet washed?
- Yes. The damaged band is worked at a reduced strength because it is more open than the rest.
- Can you work around a conservatory?
- The glazing is sheeted first and given a rinse at the end.
- Is thin-coat render different from sand and cement?
- Yes, and it is more sensitive. Thin-coat systems get a weaker mix and a longer dwell rather than more pressure.
- Is timber cladding treated the same way?
- No. Cladding takes a weaker mix, and pressure is avoided entirely because it raises the grain.
- How soon can the walls be painted afterwards?
- Once fully dry, which in practice means giving it several dry days.
- Do you clean boundary walls too?
- If they take the same method as the house, yes, in the same visit.
- What about the windows afterwards?
- Frames and glass in the spray path are wiped as the masking comes off.
Neighbouring places we work
Summary
The finish underneath is usually intact. It is the film on top that has aged. Textured finishes hold damp because of their shape, not because of neglect. Prep takes longer than application, and that is the right way round. Monday to Saturday, 8am to 7pm.
Check the gutter line too
If the staining starts at the top, the gutters are worth looking at in the same visit.
Quote for a South Pool property
Monday to Saturday, 8am – 7pm