Damp treatment prices: what each solution costs
Damp treatment prices in Portugal vary widely, and the spread says little about quality. In October 2026 we saw injections and electro-osmosis at €35–60/m², terrace waterproofing at €28–45/m² and whole-house «systems» at €4,500–20,000, according to customer reports. The marketplaces contradict each other: one shows €4–50/m², another an average of €157.50/m².
These guides are for anyone holding a quote or about to ask for one. They show what goes into the price, which questions to ask and how to compare methods that solve different problems.
The key idea: the most expensive quote is the one that treats the wrong cause. A rising-damp treatment on a third-floor flat with condensation is money lost, however good the workmanship. Before comparing figures, confirm the type of damp with the free diagnosis and check the price ranges in how much rising damp treatment costs.
Start here
How much does rising damp treatment cost? (2026 prices)
Injections, electro-osmosis and salt-retardant plasters: prices per m², a worked example, red flags and what to ask before you sign.
Full guide →
Injections vs electro-osmosis vs plaster: an independent comparison
Three approaches to rising damp side by side: how they work, when they make sense, drying time, salts, guarantees and price.
Full guide →Damp treatment quote: how to tell if it's fair (and if the method is right)
Five checks to audit a damp treatment quote before you sign: diagnosis, method, m², price per m² and guarantee.
Full guide →All guides on this topic (6)
How much does positive input ventilation (PIV / VMI) cost, and when is it worth it?
Positive input ventilation in an apartment: €800–2 500, and when it replaces a dehumidifier.
Open tool →How much does mechanical ventilation (MVHR / VMC) cost in an apartment?
About €2 500 installed. How it differs from PIV and what building work it needs.
Open tool →
How much does it cost to find a water leak (and when is it urgent)
Professional leak detection costs from a few hundred euros. The meter test you can do now, the methods used, who pays and what to do while you wait.
Full guide →Frequently asked questions
Because they often do not describe the same job. One may include stripping and replacing the plaster, the other only the injection; one measures the whole wall, the other just the affected band. Ask each quote to state the method, square metres, materials, timescale and a written guarantee. Only then does comparing the price per m² make sense.
As a rule, condensation fixes cost far less: we saw €20–300 for things you can do yourself, such as measuring, ventilating better and adjusting routines. A PIV (positive input ventilation) unit in a flat costs an estimated €800–2,500. But this only pays off if the cause really is condensation; if water is getting in, no amount of ventilation will fix it.
In July 2026 the E-Lar and Vale Eficiência programmes were closed and no new grants had been announced. Programmes open and close, so check official channels before deciding. For now, budget for the full cost without a subsidy, and be wary of anyone who promises grants to get you to sign on the same day.