A flat that is eighteen months old should not have mould in it, and yet recently completed apartments make up a growing share of the calls in HA9. The reasons have nothing to do with age or neglect. A new building arrives full of water, its envelope is sealed far more tightly than anything built before it, and it depends on a mechanical ventilation unit that most residents have never opened. Get any one of those three wrong and the flat behaves worse than a draughty Victorian house.
The water a new building starts with
Concrete, screeds, plaster and adhesives all go in wet. A sand and cement screed gives up moisture for months, and the first heating season drives that water out of the floor and into the air of the flat. In the first winter after completion, humidity in a new apartment can sit persistently high with nothing wrong at all, and growth appears in the coldest corner or on the reveal of a balcony door. Recognising construction moisture prevents an expensive misdiagnosis: the remedy is drying and ventilation, not lining.
An airtight envelope changes the rules
Older housing leaked air continuously and forgave a great deal. A flat built to current airtightness standards does not: there is no background leakage to dilute moisture, so every litre generated inside has to be removed by the ventilation system. When that system underperforms, humidity climbs steadily through the evening and stays high overnight. Single-aspect plans make this sharper still, because there is no possibility of cross-ventilation even with the window open.
The unit nobody has opened
Most of these flats have either continuous mechanical extract or a heat recovery unit, usually in a utility cupboard or a bathroom ceiling. The recurring findings are the same across blocks: the unit never commissioned to its design flow rates, filters left in since handover and completely blinded, boost not wired to the bathroom light or switched off at the isolator, flexible ducting kinked where it turns into a ceiling void, and valves adjusted or removed by residents who found them draughty. Checking flow rates at each terminal, cleaning or replacing filters, and reinstating the valve settings resolves a substantial proportion of these cases outright, and handyman for flats in Wembley covers the access panels, grilles and ducting work that goes with it.
Small plans and nowhere to dry washing
Compact flats rarely have space for a vented dryer, so washing goes on an airer in the living room or on the balcony in winter, where it dries slowly and mostly indoors. A single load puts a couple of litres of water into a space that may be a fraction of the volume of a house. Where the only route out is a window, it needs to be usable: a tilt-and-turn or a restricted opening that can be left secure overnight is worth far more than one that has to stay shut. Where the locking gear has failed and a window can no longer be left on a secure setting, locksmith cover across Preston deals with the mechanism.
Warranty, snagging and who to tell
A ventilation system that was never commissioned correctly is a construction defect, not a maintenance issue, and in a recently completed building there is usually a route to have it corrected under the developer's defects liability period or the build warranty. That route depends on evidence: measured flow rates against the design figures, dated readings of humidity in the affected rooms, and a written diagnosis. Reports are written with that use in mind, and what is covered by a remediation guarantee where a design fault remains uncorrected is set out on our national mould removal and remediation service.
Risers, bin stores and the rest of the block
New blocks concentrate services into vertical risers and put refuse and cycle stores at ground level, and both are warm, damp and rarely inspected. Rodent activity in a riser shows up as gnawed insulation and droppings on the cupboard floor, and it travels between floors. Where that is found alongside a moisture problem, the Wembley branch treats it at block level with the managing agent rather than flat by flat.
What an inspection covers
An inspection here is as much a ventilation commissioning check as a damp survey: flow rates at every terminal, filters inspected, unit settings recorded, humidity and surface temperatures logged, and the screed tested where the building is new enough to warrant it. Access to a service cupboard and to the ceiling hatch is needed, so anything stored in front of them is best moved beforehand. Pricing separates the commissioning check from any treatment and drying that follows. Older purpose-built stock nearby is covered under mould removal for rented homes in Preston.