NTB is a damp proofing and plastering specialist based in Heswall. Every job starts with a survey: we establish which mechanism is moving water into your wall, treat that mechanism, then replaster properly afterwards.
4.9 from 350+ reviewsUsually a same-day reply
EXPERIENCE
38+ years in the trade
GUARANTEE
30 years on all damp work
QUOTES
Free, in writing, after a survey
INSURANCE
£1m public liability
RECENT WORK
BAY WINDOW · STRIPPED TO BRICK, TREATED, REPLASTERED · DRAG TO COMPARE
Contaminated plaster holds the salts that draw moisture back in, so it comes off entirely. What goes back on is a salt-resistant render system, skimmed flat and left to dry through before anyone decorates.
DIAGNOSIS
MECHANISM 01
Groundwater drawn upward through masonry by capillary action, where the damp proof course has failed or was never installed.
SIGNATURE
A tide mark up to roughly a metre, salt bloom on the plaster, worst at skirting level, present year round.
MECHANISM 02
Water crossing the wall laterally through a defect in the fabric: pointing, render, gutters, a bridged cavity, raised ground levels.
SIGNATURE
Patches that darken after rain and dry back between, often high on the wall or alongside a downpipe.
MECHANISM 03
Moisture produced inside the building meeting a surface cold enough for it to condense on. A ventilation problem, not a masonry one.
SIGNATURE
Black spot mould in corners, behind furniture and on window reveals. Markedly worse through winter.
Reading one for another is why damp comes back after it has been "fixed". The survey comes first, and it decides everything after it.
METHOD
01 / 04 · DAMP IDENTIFIED
WHAT WE DO
Nine things, in the order they usually come up. All of them start from the same place: establishing the mechanism before specifying a repair.
01
Groundwater rising through masonry by capillary action, where the damp proof course has failed or was never fitted. We inject a silicone-based DPC at mortar-course level, take contaminated plaster back to the brick, and replaster in a salt-resistant render system so the hygroscopic salts left in the wall cannot bloom through the new finish.
02
Water crossing the wall from outside. We trace the route: perished pointing, cracked render, a bridged cavity, blocked gutters, external ground levels sitting above the DPC. Then we repair the defect and make good internally once the wall has dried. Treatment without the repair will not hold.
03
Moisture generated inside the building condensing on cold surfaces. We assess where the humid air comes from and where it currently goes, then specify extraction, background ventilation or insulation. No chemical damp treatment is appropriate for condensation, and we will say so if that is what you have.
04
Sand and cement render, waterproof render systems, skimming and full replastering. Plastering is half of what we do, which means damp repairs are finished by the same team rather than handed on to somebody else.
05
Below-ground rooms held dry with a cementitious tanking slurry or a cavity drain membrane, chosen on water pressure and on how the room will be used. Habitable conversions are detailed differently from dry storage.
06
Damp brings decay with it. We identify wet rot, dry rot and active woodworm, cut out and replace affected timber, treat the surrounding structure, and deal with the moisture source that caused it.
07
Perished mortar joints let water straight into the wall. We rake out and repoint in a mix suited to the brick or stone rather than the hardest one available, and repair render where it has blown or cracked.
08
A site survey with moisture readings and a written diagnosis of the mechanism at work, the repair specified and the price given before anything is booked in. Useful for homeowners, and for sales held up by a mortgage valuation.
09
NTB also carries out general building work. Where damp repairs open up into something larger, a rebuilt gable, a new floor, structural making good, it stays with one team and one point of contact.
REVIEWS
DAMP IN LIVING ROOM
Nigel did two jobs for me. Damp proof course in living room and insulation and plaster boards in bedroom. I am more than happy with the outcome. Nigel's work is meticulous, he is knowledgeable and trustworthy and I would highly recommend. The 30 year guarantee is also reassuring .
Lindsay, Wirral
MYBUILDER · 19 JUN 2026
WALL DAMPING
The response to our inquiry was prompt, the pricing was reasonable, the work was completed on schedule, and the site was left clean. I highly recommend NTB.
Sam, Manchester
MYBUILDER · 6 AUG 2026
DAMP PATCH BASEMENT WALL
Can't recommend Nigel enough! Came to quote for the work and started within a matter of days. He was incredibly friendly and efficient and made sure everything was clean and tidy afterwards. Thanks again!
antonella, Macclesfield
MYBUILDER · 4 AUG 2026
DAMP IN THE HALLWAY
Turned up to do quote and explained why I had rising damp and then came back a couple of days later and completed job very satisfied with the service.
Christine Kan, Liverpool
MYBUILDER · 28 JUL 2026
BEDROOM DAMP
Major issues in our bedroom, and we've tried all the other 'fixes', so called Nigel in for a quote which he did. Identified the problem straight away and proposed a fix, which we gave the go ahead. …
Pilchy 60
GOOGLE · LOCAL GUIDE · 127 REVIEWS
RISING DAMP
Very grateful to Nigel and his team for thoroughly identifying and treating a rising damp issue which had developed at our home. Professional from the outset Nigel quoted for the proposed work, booked this …
Sue Bates
GOOGLE · LOCAL GUIDE · 10 REVIEWS