Greater London · England
Remedial sealant & repairs in Northwick Park, Greater London
Remedial sealant in Northwick Park from a team with over 20 years’ experience. 180+ five-star Google reviews and a 4.9 rating.
- Floor or wall movement joints that have failed
- Dark patches showing through the sealant
- Worktop sealant that has shrunk and split
The process
We bring everything the job needs with us, so you don’t need to buy or prepare anything. After a quick look at the joints together, the area is protected and the work begins. It normally takes a few hours for a typical bath or shower, longer where several layers have been applied. Parking in much of London is by permit or pay-and-display, so it helps to know what’s near you in Northwick Park. It helps if you can point us to a visitor permit or a bay close to the door.
- We protect the surfaces around the joint.
- Every layer of failed sealant is stripped out.
- The joint is degreased and checked for movement and leaks.
- Once dry, a suitable sealant is applied and tooled.
- You get the cure time and our view on why the joint failed.
Preparing for the visit
- Let us know about stairs, lifts or work at height
- Keep children and pets away from the work area
- Mention any leaks or damp you’ve noticed
Get a quote
To get a quote, phone 0345 464 0079 or drop us an email and tell us where the job is and what the problem looks like. You’ll have a clear quote before we start.
Related advice
Remedial sealant in Northwick Park
Remedial jobs in Northwick Park usually fall into a few patterns: sealant over sealant, mould under the bead, leaks that come back and movement joints that have split. We strip each one back and start from scratch. If you have sealant applied over old sealant that has lifted and dark patches showing through the sealant, we can put it right.
London homes include a lot of flats, conversions and mansion blocks, and many bathrooms sit right above someone else’s ceiling. In Northwick Park, that is a good reason to put tired sealant and grout right early.
Every job comes with our 12-month guarantee.
- Location
- Northwick Park (HA1, HA3, HA0)
- Region
- Greater London
- Guarantee
- One year on every job
- Quotes
- Quoted before any work starts
- Call
- 0345 464 0079
- Updated
- 26 October 2026
Towns and villages near Northwick Park
More services for Northwick Park
Do you need remedial sealant in Northwick Park?
A lot of failed joints have been sealed over rather than replaced. Silicone does not bond to silicone, so the new layer peels, and damp and mould settle between them.
The problems people generally mention when they call are:
- Mould trapped under a layer of silicone
- Floor or wall movement joints that have failed
- Thick, messy sealant smeared over tiles
- Caulk or the wrong sealant used in a wet area
For an older house near a landmark such as Saint Cuthberts Church, walls and floors in older homes can move, and sealant and grout show it first.
Comparing quotes
- How long the guarantee is
- How hidden problems are handled
- How the surfaces are prepared before sealing
- Who turns up on the day
How we quote for remedial sealant
For a quick quote, just ask. The main things that affect it are:
- Access and height
- The old material and how stubborn it is
- The number and length of the joints
- How many rooms, windows or areas are involved
What it costs depends on the amount of work, how hard the old material is to remove and how easy the joints are to reach. You will have a clear quote before any work starts.
What to tell us for a quote
You do not need to know the technical terms. Just tell us:
- Any previous sealing or DIY work
- Pictures of the joints, sent by email
- The address or postcode of the job
- What’s wrong with the joints now
The more we know about the job, the more useful the quote. Let us know the location, the problem and roughly how many joints.
Surface by surface
Worktops & kitchens
Old kitchen sealant pulls back from the wall over time. We strip it, degrease the joint and reseal colour-matched to the worktop.
Windows & doors
Frames resealed over the top end up with hard, layered mastic. We remove it all and clean back to sound surfaces before backing and resealing.
What sealant work cannot fix
It helps to know what we cannot do:
- Sealant in an older building that needs testing for asbestos first
- Cracks in the fitting rather than the joint
- A leaking trap, valve or supply pipe
Not sure which it is? You can phone 0345 464 0079 or drop us an email and we’ll tell you honestly before you book.
What we seal
- Expansion joints
- Failed movement joints
- Mouldy bath & shower sealant
- Leaking tray & enclosure joints
- Shrunken worktop sealant
- Botched or over-sealed joints
What happens if it’s left?
Adding more sealant is the usual quick fix, and it rarely works. It doesn’t grip the old layer, leaving the leak in place and one more layer to cut out later. In older London homes, water behind a failed joint soaks into brick and timber without much sign, and once it shows in Northwick Park, the repair is bigger than a sealant job.
Doing several joints on one visit is normally more efficient than separate visits, so tell us about everything that needs sealing. We’ll give you a clear price for the lot.
Why choose Mr Mastic in Northwick Park
- Colour picked to suit the job
- 20+ years of sealant experience
- Anti-fungal silicone where joints get wet
- Experience in homes, commercial sites and hotels
Read our cost guide or customer reviews.
Northwick Park: your questions answered
Is parking an issue for remedial sealant in Northwick Park?
It can be, so it helps to tell us about permits, visitor bays or off-street space when you book. The visit is then planned around what’s available.
I live in a flat in Northwick Park. Can a failed seal leak into the flat below?
Yes, and the first sign is often a stain on the ceiling below. A proper reseal before the leak starts is the easy fix.
Do I need to be at home?
Access is agreed with you when the job is booked. Indoors, that generally means someone at home.
My shower still leaks after a reseal. Can you sort it?
Yes, normally. We check it’s the sealant and not the tray, valve or waste, then the joints are stripped and resealed.
Will you leave a mess?
No. We work neatly, protect the area around the joints and tidy up afterwards.
What should I tell you?
Where the job is, what the problem is and roughly how big it is. Photos by email help too.
Can you work on commercial sites?
Yes. We work in offices, washrooms, hotels and other commercial premises, as well as homes. Working times can be discussed when we quote.
Where are you based?
We’re based in Crawley, West Sussex, and we cover South East England, London and all of Scotland.
Landlord and commercial work in Northwick Park
Housing providers, facilities teams and property managers book us too in Northwick Park and across Greater London. Several sites can go on one quote, and we’re fully insured for the work.
We work for letting agents and landlords as well as homeowners. Sealant work between tenants is a simple way to keep a property in good order.
Northwick Park homes and their sealant
In a London flat, water from a failed bath or shower seal can reach the neighbours below, so tired sealant is best dealt with early. London has hard water, so limescale builds up on sealant, grout and fittings.
If you look after a building such as Harrow High School, we reseal washrooms and kitchens in schools and businesses as well as homes. If you let a flat or house near Kenton station, failed or mouldy sealant is worth putting right between tenancies, before it turns into a leak.
Northwick Park is about 1 mile south-west of Kenton, in Greater London. Across the HA1 area, we can carry out remedial sealant at your property. Our area takes in 764 places across Greater London, from the larger towns to small villages. Our London page covers work nearby, about 11 miles away.
We cover every part of the HA1, HA3 and HA0 postcode area for remedial sealant and the streets around it. We cover properties on Lyon Road, Manor Road and Gayton Road and the roads around them. With the A404 close by, Northwick Park is easy for our applicators to reach. Nearby, we also carry out remedial sealant in Greenhill (1 mile north-west), Harrow on the Hill (1 mile south-west), South Kenton (1 mile east), Kenton (1 mile north-east) and Harrow (1 mile west). We also work in nearby towns such as London (11 miles south-east), City of Westminster (9 miles south-east), Marylebone (9 miles south-east), Kensington (7 miles south-east), St Pancras (10 miles east) and Shoreditch (11 miles east).
Local landmarks in Northwick Park
Locally, jobs take us to homes and businesses close to St Anselm's Catholic Primary School, Orley Farm School and Preston Park and the streets around them. Northwick Park’s nearest station is Kenton station, about 0.6 miles north-east of the centre. Well-known places in the area include Northwick Park Hospital (within half a mile north-east) and Kodak Museum (1.5 miles north-west). Green spaces nearby include Masons Field and Northala Fields.