Protecting a house from damp and mould: causes, ventilation, dehumidifying
Protecting a house from damp and mould in Batumi is needed even for a new house without leaks: humidity rarely drops below 70 %, and moisture settles on cold corners and walls. We find the cause, insulate thermal bridges, fit extract fans, supply vents or heat recovery ventilation, and sensor-controlled dehumidifiers for houses that stand closed. Mould treatment of walls from 24 ₾ per m².
from 24 ₾/m²mould treatment of walls: cleaning and two coats of antiseptic, per m². The final price is confirmed once agreed.
- Timeline: protecting a house from damp usually takes 2–6 weeks, plus humidity monitoring over a season
- Warranty: Works carry a 2-year warranty
Who it’s for
The house smells damp and the corners are darkening
You live abroad and by spring the house is covered in mould
Mould appears in summer in air-conditioned rooms
The facade is covered in black staining and algae
You are building a house and want to rule out damp from the start
What’s included
- survey: moisture meter, thermal camera, humidity readings
- finding and removing the cause
- extract fans and supply vents in rooms
- heat recovery ventilation
- dehumidifiers with sensors and drainage
- humidity sensors with phone access
- mould treatment of walls
- facade washing and water-repellent treatment
Protecting a house from damp and mould in the subtropics
Protecting a house from damp and mould in Batumi is needed by almost every house, even a new one without a single leak. Air humidity here rarely drops below 70 %, and moisture settles on everything colder than the air: the corners of external walls, concrete columns, walls behind wardrobes, window reveals. In summer the opposite effect is added: warm humid air from outside gets into a room chilled by the air conditioning. Mould does not need a puddle; it is enough for the humidity at a wall to stay above 80 % for weeks.
Three causes of damp
| Cause | What it looks like | What we do |
|---|---|---|
| Cold surfaces | A band under the ceiling, dark corners, the outline of a column | External insulation, breaking thermal bridges |
| Air that does not change | A damp smell, patches in bathrooms and behind furniture | Extract, supply, heat recovery ventilation |
| Water from outside or below | A patch grows after a downpour, salt near the floor | Waterproofing, gutters, drainage |
Most often the causes act together, so treating one is pointless. First we find where the moisture comes from, and only then treat the walls. How mould that has already appeared is removed in an apartment is covered on the mould and fungus removal page.
What we build in during construction
- a damp-proof course between the foundation and walls so moisture from the ground does not rise;
- continuous external insulation, including slab edges and columns;
- roof overhangs and gutters that carry water away from the walls;
- extract fans venting outside in every bathroom and the kitchen;
- supply air in every bedroom or heat recovery ventilation.
On facades that get wettest in driving rain, a ventilated facade works well: the rain stays on the cladding, and the wall behind it dries out; more on the ventilated facade page. Heat recovery ventilation is described on the ventilation and heat recovery page.
A house that stands closed
The dampest situation in Batumi is a house or apartment whose owner lives abroad and comes for a couple of months in summer. In winter the windows are shut, there is no heating, the air does not move, and by spring it smells damp and textiles and wardrobes are covered in mould. What helps: a dehumidifier draining into the sewer and running on a humidity sensor, an extract fan on a timer, wardrobe doors left ajar, furniture kept away from external walls. Humidity and temperature sensors can be connected to a phone through a smart home, and the owner sees what is happening in the house from any country.
If the damp is already there
We start with a survey: a moisture meter, a thermal camera and humidity readings over several days show whether it is condensation or water in the wall. Then we remove the cause, dry the area out, take off affected finishes and treat with antiseptic. If the cause is a cold wall and it cannot be insulated from outside, we insulate from inside with a vapour barrier. A facade growing algae and black staining is washed and treated, and porous cladding gets a water repellent.
How much damp protection costs
Treating walls for mould, with cleaning and two coats of antiseptic, costs from 24 ₾ per m², mould removal with finishes taken off from 78 ₾ per m². A damp survey of the house with a report from 570 ₾. A domestic dehumidifier from 840 ₾, a wall trickle vent from 330 ₾, an extract fan with a humidity sensor from 330 ₾. Heat recovery ventilation for a 120–180 m² house from 17 400 ₾. Facade washing and algae treatment from 13 ₾, a water-repellent facade treatment from 19 ₾ per m². The final cost is set after a survey and an agreed estimate.
Stages and timelines
-
Survey
2–5 days
Readings over several days, causes.
-
Cause
1–3 weeks
Leaks, thermal bridges, ventilation.
-
Drying
1–2 weeks
Dehumidifiers, airing.
-
Treatment
3–7 days
Removing finishes, antiseptic, redecoration.
-
Monitoring
a season
Sensors, repeat readings.
Local specifics in Batumi
Mould in Batumi is seasonal. From November to March external walls cool down while the air in the house stays damp, and the patches in the corners grow. In summer they fade, and an owner who arrives in July often does not see them, but in November they reappear in the same place. There is summer mould too: in July and August the outdoor dew point can be above +20 °C, and if the air conditioning has chilled a bedroom with the balcony door open, moisture settles on the cold ceiling.
Walls facing the sea get wetter in driving rain than the others, and algae and black staining grow on them faster. In houses on slopes, water from the ground rises up the plinth walls if there is no damp-proof course. Houses and apartments that stand closed all winter get damp most of all.
Materials and brands
Moisture meters, hygrometers, a thermal camera, humidity loggers for readings over several days. Dehumidifiers with condensate drainage and a humidistat. Trickle vents with filters, extract fans with humidity sensors and timers, heat recovery units. Antiseptics and fungicidal primers, vapour-open plasters and paints. Facade cleaning products for algae, water repellents for stone, brick and concrete.
What makes up the cost
Timeline: protecting a house from damp usually takes 2–6 weeks, plus humidity monitoring over a season
- affected area and causes
What raises the cost
- damp from several causes at once
- removing finishes over large areas
- whole-house heat recovery ventilation
- internal insulation in lived-in rooms
What lowers the cost
- one cause, found straight away
- prevention at the construction stage
We prepare the exact estimate from measurements and photos. It’s free and comes with no obligation.
Get an estimateGuarantees
Works carry a 2-year warranty. Dehumidifiers, fans and units carry the manufacturer's warranty. If, after the cause has been removed and the area treated, mould returns in the same place within the warranty period, we investigate and fix it at our own expense.
Questions and answers
How much does protecting a house from damp and mould cost?
Mould treatment of walls costs from 24 ₾ per m², removal with finishes taken off from 78 ₾ per m². A damp survey from 570 ₾, a dehumidifier from 840 ₾, an extract fan with a humidity sensor from 330 ₾, heat recovery ventilation from 17 400 ₾. The final cost is set after a survey and an agreed estimate.
Why is a new house without leaks damp?
Because of cold surfaces and air that does not change. Humid air settles on uninsulated corners, columns and reveals, and without extract and supply ventilation the steam from the shower and kitchen stays inside. What is needed is insulation of thermal bridges and ventilation, not new waterproofing.
What should be done with a house that stands closed in winter?
Install a dehumidifier draining into the sewer with a humidity sensor, run the extract fans on a timer, leave wardrobe doors ajar and move furniture away from external walls. Sensors with phone access will show if humidity starts rising. The house is worth checking in person once a month.
Does air conditioning help against damp?
In dry mode it helps, but only with windows and doors shut. If a room is chilled and the balcony opened, warm humid air from outside settles on the cold ceiling and walls, and mould appears even in summer. For houses where nobody lives, a separate dehumidifier is more reliable.
Is treating the walls with antiseptic enough?
Not unless the cause is removed. Antiseptic kills mould on the surface, but if the wall stays cold or wet, the patch returns within a season. Treatment makes sense once the leak, thermal bridge or stagnant air has been dealt with, and soft finishes with mould growing through them are better removed than soaked.
Further reading
Send photos of the patches and tell us when they appear: we will find the cause within 24 hours
We reply within an hour during business hours. Message us or leave a request: we’ll call you back, go over the details and suggest the next step.
Mon–Fri 10:00–19:00, Sat 11:00–16:00