Free Damp Surveys& Diagnosis in Harrow

Rising damp holds a fairly consistent height above floor level, usually with a tide mark, salt deposits and blown plaster, and it does not respond much to the weather. Penetrating damp appears as isolated patches at any height and darkens during and after driven rain. Condensation collects on cold surfaces, window reveals, external corners, behind wardrobes on north walls, often with black spot mould and no salting.

Plumbing and drainage leaks mimic all three but usually stay constant regardless of weather and can be localised to pipe runs, wet rooms or the floor above. Construction moisture in new render, screed or plaster reduces steadily over months rather than persisting.

Electrical resistance moisture meters give useful comparative readings across a wall and up its height, and they are read as a pattern rather than a single number, because salts and foil-backed papers can skew them. Where a reading needs interpreting, it is checked against the physical evidence: plaster condition, efflorescence, timber state, and whether the affected zone corresponds to something outside.

The external inspection carries as much weight as the internal one. Ground levels above DPC, render bridging the DPC, open or eroded joints, cracked or hollow render, perished mastic at openings, missing sill drips, loose copings, blocked or split rainwater goods and defective flashings are all recorded, because each one is a potential entry route with a matching internal pattern.

Where damp has been treated before, we look for the three usual omissions: an injected damp proof course with no salt-retardant replastering, internal waterproof coatings applied over an untreated ingress, and bridging that was never corrected so a sound DPC is being bypassed.

Knowing what was done previously changes the specification, and often reduces it, there is no point paying twice for an element that was done correctly the first time.

When a mortgage valuation or homebuyer report refers a damp issue for specialist investigation, what is needed is a clear statement of cause and a costed scope of remedial work. That is what our survey produces, and where treatment goes ahead it is backed by a 10-year workmanship guarantee and a 10-year QANW insurance-backed guarantee, the documentation buyers, surveyors and lenders look for.

For sellers, having the diagnosis and a fixed-price quotation in hand keeps control of the negotiation rather than leaving a buyer to imagine the worst-case figure.

Domestic surveys cover houses, flats, maisonettes and converted properties, including leasehold situations where responsibility for the defect may sit with the freeholder, worth establishing before anyone commissions works.

Commercial surveys follow the same method with added attention to trading impact, access equipment and phasing. In both cases the outcome is the same: a cause, a scope and a fixed price.