Lian Construction diagnoses rising damp, penetrating damp and condensation before recommending any fix, using moisture profiling and carbide testing rather than a single meter reading, then treats the specific cause at fault — from chemical DPC injection to basement tanking — across Victorian terraces, ex-council flats and 1930s semis alike.
Ealing overview
Damp Proofing in Ealing
West London borough benefiting from Wembley-area regeneration, with consistent buy-to-let refurbishment activity. Ealing falls well within the West London ground Lian Construction covers on a regular basis. For diagnosing and treating rising damp, penetrating damp, condensation and basement tanking issues in Ealing, that local knowledge means fewer surprises once work is on site and a team that already understands the borough's typical property stock.
Ealing's housing stock reflects its position as an established West London suburb that grew steadily through the Victorian and Edwardian periods before filling out further between the wars. Expect a mix of Victorian and Edwardian terraces and semi-detached houses, along with a good number of 1920s and 1930s bay-fronted semis typical of outer London's interwar expansion. Purpose-built mansion blocks and low-rise flats sit alongside the houses in many areas, and more recent infill development has added flats and townhouses on smaller sites over the decades. Properties of this age generally come with the usual list of refurbishment needs: ageing roofs, single-glazed or early double-glazed windows, dated wiring and plumbing, and layouts that often don't suit modern living without some reconfiguration. Loft conversions and rear or side extensions are common ways owners add space rather than move. As with much of outer London, condition varies a lot street to street depending on when a property last had significant work done, which is worth bearing in mind when planning a refurbishment budget or scope.
Regeneration activity around the Wembley area has had a knock-on effect on demand in neighbouring parts of West London, including Ealing, as buyers and renters look slightly further out for value while still wanting reasonable access to improving transport and amenities. This tends to support steady interest in rental property, and landlords in the borough have kept up a fairly consistent pace of refurbishment work, whether that's turning round properties between tenancies, upgrading kitchens and bathrooms to hold rents at a competitive level, or bringing older stock up to current standards for letting. For homeowners, the same regeneration effect can make extending or improving an existing property more attractive than moving, particularly where nearby development is pushing up expectations for finish quality. Because Ealing sees this kind of ongoing buy-to-let and owner-occupier refurbishment demand, competition among contractors for smaller and mid-sized jobs can be steady rather than sparse, so landlords and homeowners are often weighing up contractors on reliability and turnaround time as much as price. Getting quotes early and being clear about scope tends to help avoid delays, especially for landlords working to a fixed window between tenants.
Typical damp proofing prices in London
Item
Typical range
Diagnostic damp survey
£200–£500
Chemical DPC injection, per linear metre
£70–£120
Single-wall DPC injection with hack-off & re-plaster
~£3,250 total
Basement/cellar tanking (per m²)
£90–£220
General London market guidance, not a fixed quote — actual pricing depends on a site survey. Full breakdown: cost guide.
Basements and Semi-Basement Conversions: Hydrostatic Pressure, Not Rising Damp
Basements and semi-basement flats, common across conversions in Kensington, Islington and Camden among other boroughs, face a damp mechanism that has nothing to do with capillary rise or airborne moisture: hydrostatic pressure from groundwater pushing against an earth-retaining wall below ground level, constantly and from every side. A badly detailed cementitious tanking system applied over an active water source without a sump and pump in place doesn't stop that pressure - it gets pushed off the wall over time, or the water finds the weakest point instead, often the junction between the tanked wall and the floor slab, where it forces its way in sideways. A proper tanking specification accounts for where the water is coming from and how much of it there is, which is why a sump and pump is often part of the system rather than an optional extra, particularly where the water table is high or a nearby watercourse affects groundwater levels. This is priced by the square metre - roughly £90 to £220 depending on whether it's a cementitious slurry or a studded membrane system - and for a full cellar or basement room in London that typically lands somewhere between £4,000 and £14,000 once labour, materials, sump and pump where needed, and finishing are all included. Where a basement is being converted into habitable space rather than just tanked as storage, Building Control involvement is close to unavoidable, since means of escape, ceiling height and ventilation all come into play alongside the waterproofing itself.
Why Victorian and Edwardian Terraces Behave Differently to a 1930s Semi
Rising damp treatment on a Victorian terrace in London starts from a different set of assumptions than the same job on a 1930s semi, because the two were built to keep water out in completely different ways. Most of London's older housing stock - the Victorian and Edwardian terraces that make up a large share of streets across Lambeth, Hackney, Wandsworth, Haringey and much of Zones 2 and 3 - was built with solid one-brick (nine-inch) walls and no cavity, relying on an intact damp-proof course, sound external pointing and reasonable ground levels rather than a cavity breaking the path of water. Over more than a century, a lot of those original slate or bitumen DPCs have been bridged by a raised flower bed, a re-laid path, or an infilled front lightwell that's brought the external ground level above the internal floor, letting groundwater walk around the damp-proof course at low level rather than through it. Many of the earliest Victorian houses never had a DPC at all and depended on breathable lime plaster and lime mortar to manage moisture by letting it evaporate out through the wall surface - so when a later owner strips that back to cement render or gypsum plaster, which don't move moisture the same way, the wall produces symptoms that look exactly like rising damp but are really a materials-compatibility failure, not a missing DPC. A 1930s semi with cavity walls is a different building type again: the cavity exists specifically to break capillary rise, so damp patches on the inner leaf are far more likely to come from corroded wall ties bridging the cavity or badly installed cavity insulation creating a cold bridge and interstitial condensation than from classic rising damp, and treating either as rising damp spends money on the wrong repair entirely.
Diagnosis before treatment - moisture profiling and carbide or gravimetric testing to BS 6576, not a single moisture-meter readingExternal bridging checked first: raised ground levels, blocked airbricks and failed flashings inspected before any chemical DPC is recommendedSingle accountable contractor for survey, Party Wall Act and Building Control coordination, and the remedial trades through to final decorationRegular coverage of Ealing and the wider West London area
Signs to look for
Do you need damp proofing in Ealing?
Airbricks under a suspended timber ground floor that have been painted over, rendered flush, or blocked by a flowerbed or extension, cutting off sub-floor ventilation and risking a musty smell and softening joists
Persistent morning condensation on windows regardless of the weather, particularly in a 1960s or 70s ex-council flat or concrete-frame maisonette - usually cold-bridging at the perimeter beam or window reveal rather than any rising damp mechanism
Water ingress, tide-lining on an existing tanking system, or a musty smell in a basement, cellar or semi-basement room that worsens after rain or where the local water table is high, suggesting hydrostatic pressure the tanking isn't relieving
A landlord who has received an HHSRS Category 1 hazard notice from the council, or a social housing tenant complaint that now falls under Awaab's Law's fixed investigation and repair timescales for damp and mould
How the work is handled in Ealing
Step 1Initial diagnostic survey on site - visual inspection of internal and external walls, external ground levels and DPC line check, moisture profiling at multiple heights, and carbide or gravimetric testing to BS 6576 where rising damp is suspected, since a surface meter reading alone cannot confirm it
Step 2Identify which of the three causes is actually present - rising damp, penetrating damp, or condensation - and agree the diagnosis and recommended fix with you before any remedial work is priced or scheduled
Step 3Clear obvious external bridging points first - built-up ground levels, blocked or rendered-over airbricks, leaking gutters, defective flashings, cracked render - since these often need addressing regardless of whether a chemical DPC is also required
Step 4Where excavation or wall-cutting is involved, assess Party Wall etc. Act 1996 notice requirements and serve the correct notice (Party Structure Notice or Notice of Adjacent Excavation) at least two months before work starts, and confirm the Building Control route (full plans or building notice) where structural elements are affected
Step 5Hack off internal plaster to around a metre above the visible damp line where rising damp is confirmed, then drill and inject the chemical damp-proof course into the mortar bed course to BS 6576 spacing and depth
Step 6Allow the treated masonry several weeks of proper drying time before replastering, rather than replastering over wet masonry to hit a faster completion date
Step 7Re-plaster with a salt-retardant or lime-based render system appropriate to the wall's construction and salt contamination, not a standard gypsum finish
Step 8Carry out any external fabric repairs identified at survey - repointing in lime mortar where original, flashing renewal, parapet or gutter repair - before internal redecoration, since internal-only work fails if the external cause is left untouched
Step 9For condensation, install extract ventilation or a PIV unit and address cold bridging and heating/ventilation patterns rather than any chemical DPC or tanking, then complete final internal decoration once plaster or render has fully dried and any salt migration has stabilised, with a snagging visit to confirm no residual staining
Questions
Damp Proofing questions in Ealing
How quickly can Lian start diagnosing and treating rising damp, penetrating damp, condensation and basement tanking issues in Ealing?
Ealing is part of our regular West London coverage, so once we've surveyed the property we can usually confirm a start date quickly. Send the address and scope and we'll arrange the next step.
Do you cover all of Ealing?
Yes. Ealing falls within the area Lian Construction serves across Greater London.
Do you carry out refurbishments for landlords with tenants moving out soon?
Yes, this is a fairly regular type of job for us. If you can give us the moving-out date as early as possible we can look at scheduling around it, though exact timing depends on scope of work and our current workload. For a straightforward refresh (redecoration, minor repairs, kitchen or bathroom updates) a week or two is often realistic, but larger works will need more notice and a proper site visit to confirm.
How much does a chemical damp-proof course injection cost per linear metre?
The injection itself typically costs £70 to £120 per linear metre. For a single affected wall - including hack-off to about a metre above the visible damp line and salt-retardant re-plastering - a typical job runs around £3,250 in total once drying time, labour and materials are all accounted for. Costs rise from there depending on how many walls are affected and whether external repairs are also needed to stop the source of the moisture getting in.
My ex-council flat has black mould - is it condensation from cold bridging, or rising damp?
Almost certainly cold-bridging condensation rather than rising damp. Concrete-frame ex-council flats and maisonettes from the 1960s and 70s generally don't suffer classic rising damp - the concrete construction doesn't have the same capillary path as a solid brick Victorian wall. Their black mould is usually caused by cold-bridging at the concrete perimeter beam or window reveals, where the internal surface drops below the room's dew point in cold weather. Injecting a chemical DPC does nothing for this; the fix is ventilation - extract fans or a PIV unit - and addressing the cold bridge with insulation, typically costing £300 to £1,800 rather than the £3,000-plus of a DPC injection aimed at a mechanism that isn't present.
Do I need Building Control or Party Wall Act sign-off for damp proofing?
It depends on the work. A straightforward chemical DPC injection on your own wall usually doesn't need Building Control, but underpinning, new sub-floor ventilation involving floor removal, or a basement conversion does, via the full plans or building notice route. If excavation for tanking is within 3m or 6m of a neighbouring foundation, or a DPC is injected through a shared party wall, the Party Wall etc. Act 1996 requires a notice served at least two months before work starts - a Notice of Adjacent Excavation for the former, a Party Structure Notice for the latter.
Talk to Lian Construction about Ealing
Send the site address in Ealing, photos if available, and the damp proofing work you need. We can review the scope and arrange the next step.