01634 47989007460 072891 Mon–Fri 8am–6pm · Sat 8am–3pm HomeAboutServicesDamp & Waterproofing Damp ProofingTanking & Waterproofing Roofing RoofingNew roofsRoof repairsFlat roofsChimney repairsCommercial roofing Exterior & Finishes RenderingExterior paintingFascias & soffitsWood rot repairsNew PVC All services Service AreasMedwayMaidstoneRochesterStroodGillinghamChathamRainhamSittingbourneSheernessAll areas Our WorkReviewsContactRequest Estimate - Home - Services - Damp Proofing Services # Damp Proofingin Medway & KentDry Walls, Traced to the Cause You get the damp traced to its actual source, treated once, and the wall replastered and redecorated-ready, instead of paying for cosmetic patching that reappears next winter. Get my free survey07460 072891 9.97 out of 10 from 12 Checkatrade reviews, free survey and a fixed written price before any work starts. - 12 Checkatrade reviews 9.97 out of 10 average score - Checkatrade & Bark listed Verified customer reviews on both platforms - Free survey, fixed written price The cause diagnosed before the work is priced - Open 6 days a week Mon–Fri 8am–6pm, Sat 8am–3pm - Company no. 15471708 Kent-based, working across Medway from Chatham ## What damp proofing involves, and when you need it Damp proofing is the work of stopping water getting into a wall and then repairing the damage that water has already done. In Medway housing stock that usually means one of three things: rising damp drawn up through solid brickwork where the original slate or bitumen damp proof course has failed, penetrating damp pushed through walls by driving rain off the estuary, or condensation caused by warm moist air with nowhere to go. The three look similar on a wall and are fixed in completely different ways, which is why we survey before we quote. A survey means moisture readings taken at intervals up the wall, external ground and render levels checked, gutters, downpipes and thresholds inspected, and salt contamination in the plaster assessed. Only then do we specify: a new chemical damp proof course injected into the mortar bed, external repairs to stop water ingress, salt-retardant replastering, or improved ventilation. You get that specification in writing with a fixed price, so there is no mid-job change of scope. Where plaster has been contaminated by hygroscopic salts it will keep drawing moisture from the air no matter how well the wall is treated, so it comes off and goes back on in a sand and cement render coat with a salt inhibitor, finished in skim ready for decoration. Skirtings, sockets and floor coverings are lifted and protected first, and the debris leaves with us. ### Who this is for - Homeowners with tide marks, blown plaster or peeling paint on ground-floor walls - Landlords with a tenant complaint, an EPC issue or an environmental health letter - Buyers and sellers whose survey has flagged high moisture readings before exchange - Anyone converting a cellar, garage or outbuilding into habitable space - Commercial premises with damp affecting stock, flooring or wall finishesRing the office on 07460 072891 or use the contact page and we will give you a realistic survey date on the call. You can also see everything we do across Medway or read our customer reviews. ### Related services - Tanking & Waterproofing - Rendering - Wood rot repairsAll services ### Areas we cover - Medway - Maidstone - Rochester - Strood - Gillingham - Chatham - Rainham - Sittingbourne - Sheerness ## What happens if it is left Damp does not stay a decorating problem. Persistent moisture in a wall carries salts into the plaster, rots skirtings, joinery and floor timbers in contact with the masonry, and where it reaches structural timber it invites wet rot and eventually dry rot, a repair measured in structural carpentry rather than plastering. It also costs money every month before it costs money in repair. A wet wall conducts heat out of the building, so rooms take longer to warm and never feel comfortable, and the heating bill absorbs the difference. Mould growth on cold damp surfaces is a recognised respiratory irritant, which matters most in bedrooms and in properties with children or older occupants. For landlords the escalation is legal as much as physical: damp and mould sit squarely inside the fitness-for-habitation duties, and an unresolved complaint can become an enforcement notice. For sellers, a moisture reading on a buyer's survey either knocks money off the price or stalls the sale entirely until it is dealt with by someone who can show what was done. ### Common mistakes we are called in to undo - Painting over the tide mark with a damp-seal paint, which traps moisture and blows again in months - Assuming every damp wall is rising damp when the real cause is a blocked gutter or raised external ground - Injecting a new damp proof course but leaving salt-contaminated plaster on the wall - Sealing a solid wall with waterproof render outside and giving the moisture nowhere to leave - Blocking up air bricks and closing every vent, then wondering why condensation and mould followed ## How the job runs, step by step - Step 1 ### Inspection We take moisture readings at intervals up the affected walls, check external ground levels, render, gutters, downpipes and thresholds, and look at ventilation and heating patterns inside. - Step 2 ### Diagnosis Readings and external findings together tell us whether you are dealing with rising damp, penetrating damp, condensation or a combination, and we explain which, with the evidence. - Step 3 ### Written specification and fixed price You get the works set out line by line: external repairs, damp proof course injection, plaster removal, replastering, ventilation. One price, in writing, before anything starts. - Step 4 ### Treatment Contaminated plaster is removed, the new damp proof course is injected into the mortar course, external ingress points are repaired and the wall is replastered with a salt-inhibited system. - Step 5 ### Verification and completion We re-check readings, walk the finished work with you, explain drying-out times before decorating, and clear the site. Nothing is signed off from a doorway. ## What you get out of it ### Cause fixed, not covered The source of the water is repaired first, so the wall stays dry after the plaster has cured rather than through one dry summer. ### Warmer, cheaper rooms A dry wall insulates. Rooms reach temperature faster and hold it, which shows up in the heating bill through the winter. ### Protects the structure Stopping moisture at the wall protects skirtings, joinery, floor timbers and wall plates before rot repairs are needed. ### Decoration-ready finish Walls come back skimmed and flat, so you are decorating rather than commissioning a second trade to make good. ### Clear evidence of works The written specification and completed works give landlords, buyers and solicitors something concrete to point at. ### One team, one price Damp treatment, external repairs, plastering and decoration prep are carried out by our own people, so nothing falls between trades. ## Damp Proofing in detail: materials, methods and variations ### Materials and systems we use Chemical damp proof courses are installed as injection cream or fluid into drilled holes in a mortar bed, forming a continuous water-repellent band through the wall. Cream systems suit most solid brick walls in Medway because the dose stays where it is placed rather than running into voids. Where masonry is rubble-filled or heavily perished, we use higher-volume injection or a physical repair to the affected coursing instead. Replastering is a specified system rather than a bag of multi-finish. A cement and sand render coat with a waterproofing and salt-inhibiting additive holds back residual salts, then a finishing skim gives the flat surface for decoration. Where a wall must breathe, older solid-wall construction and period property, we use lime-based renders and breathable finishes so moisture leaves as vapour instead of building up behind an impermeable skin. For below-ground or high-exposure walls the specification moves to cavity drain membrane: a studded HDPE sheet mechanically fixed to the wall that lets water pass behind it to a drainage channel, with the finish built off battens or a plastered mesh face. ### Methods and variations Rising damp is treated by reinstating a barrier at the base of the wall and dealing with the contaminated plaster above it, typically 300mm above the highest tide mark. Penetrating damp is treated externally: repointing failed mortar joints, repairing or renewing render, sealing around window and door reveals, correcting flashings and clearing or renewing rainwater goods so water is taken away from the wall. Bridged damp proof courses are one of the most common findings in Medway and one of the cheapest to fix. Raised patios, new driveways, flower beds and render carried down over the damp proof course all let water step over the barrier. Lowering ground levels, forming a clear margin and stopping render short of the barrier often reduces a wall's readings without any injection at all. Condensation is a ventilation and heating problem, so the fix is ventilation and heating: clearing and reinstating air bricks, fitting extraction in kitchens and bathrooms, positive input ventilation in the loft where appropriate, and insulating cold spots that act as condensation targets. ### Where it applies, and residential versus commercial Terraced and semi-detached Victorian and Edwardian housing across Rochester, Chatham and Gillingham is where we see the most failed original damp proof courses: slate courses that have cracked with settlement, or bitumen that has aged out. Post-war housing tends to present with bridging, render failure and condensation instead. Coastal and estuary properties in Sheerness and along the Medway take driving rain from one prevailing side, so penetrating damp is often confined to a single elevation. Commercial work runs on different constraints rather than different physics. Shops, units and offices need the work sequenced around trading hours, dust and noise controlled, stock and flooring protected, and clear access maintained. We plan phased sections so a unit can stay open, and we carry out the disruptive removal work outside opening times where the schedule allows. ## Recent damp proofing jobs in Medway & Kent ## Damp Proofing: your questions answered How much does damp proofing cost in Medway?It depends on the length of wall, the cause and whether replastering is needed, a single bridged wall is a fraction of a full injected course with replastering. Rather than guess, we survey, then give you one fixed written price covering everything in the specification. There is no charge for the survey and no obligation. How long does the work take?Most single-room damp treatments with replastering are a two to four day job. Whole-ground-floor works run to a week or slightly more where external repairs are included. We give you the duration in writing with the quote so you can plan around it. How do you know it is rising damp and not condensation?Readings taken up the wall behave differently: rising damp shows a moisture gradient decreasing with height and salt contamination in the plaster, while condensation shows surface moisture and mould on cold spots without that gradient. We take the readings and show you what they say before specifying anything. Do I have to move out while you work?Almost never. We work room by room, sheet up and protect floors and furniture, and clear debris daily. The work is dusty during plaster removal, so we agree in advance which rooms are affected on which days. How soon can I decorate afterwards?New render and skim need time to dry through, as a guide, allow around a week per 5mm of thickness in normal conditions, and use a breathable mist coat first. We tell you the realistic date for your specific walls at handover rather than a generic figure. How long does a damp proof course last?A correctly installed chemical damp proof course is a long-term repair measured in decades, not seasons, provided the conditions that caused the original failure are also fixed. That is why we insist on correcting ground levels, render and rainwater goods as part of the job. Can you deal with damp for a mortgage or survey report?Yes. This is a large part of what we do around exchange dates. We survey, quote against the surveyor's comments, carry out the works and set out clearly what was done so it can be passed to a solicitor, buyer or lender. Do you handle emergencies and urgent leaks?Where water is actively entering the building we prioritise stopping the ingress first: roof, gutter or flashing repairs, then deal with the internal damp once the wall can dry. Call the office on 07460 072891 and we will tell you honestly how soon we can attend. Which areas do you cover for damp proofing?Medway in full: Rochester, Chatham, Gillingham, Strood and Rainham, plus Maidstone, Sittingbourne, Sheerness and the surrounding Kent towns. ## Get damp proofing priced properly: free survey, fixed written price Tell us what you are seeing and we will book a survey, diagnose the cause and give you one written price. 9.97 out of 10 from 12 Checkatrade reviews across Medway and Kent. Get my free surveyCall 07460 072891 Covering Medway, Maidstone, Rochester, Strood, Gillingham, Chatham, Rainham, Sittingbourne, Sheerness and the surrounding Kent towns. Damp proofing, tanking, rendering and roofing specialists working across Medway and the wider Kent area. Company number 15471708. CheckatradeBark ## Get in touch - 01634 479890 - 07460 072891 - info@intellroofingandbuilding.co.uk - 116 Chatham Grove,Chatham, Kent, ME4 6LZ ## Opening hours - Monday8am – 6pm - Tuesday8am – 6pm - Wednesday8am – 6pm - Thursday8am – 6pm - Friday8am – 6pm - Saturday8am – 3pm - SundayClosed ## Areas covered - Medway - Maidstone - Rochester - Strood - Gillingham - Chatham - Rainham - Sittingbourne - Sheerness © 2026 Intell Roofing & Building Ltd. All rights reserved. AboutPrivacy policyCookie policyTerms & conditionsRequest a free estimate Call nowFree estimate