Greater London · England
Erith New Build Mastic
Professional new build mastic in and around Erith, with every bit of old sealant taken out first and a one-year guarantee.
- Worktop and upstand sealant coming away
- Beads laid onto grit and dust from the build
- Smeared, uneven beads picked up at snagging
Different surfaces, different methods
Windows and doors
Internal joints between frames and plaster often crack as a new house dries. We cut out the cracked bead and reseal with a flexible sealant.
Kitchens
Worktops in new homes can move slightly as the house dries, opening gaps behind the upstand. We reseal them with a flexible sealant.
New build mastic in Erith, done properly
Our new-build work comes in two parts: plot mastic for developers, and putting right failed sealant for people who’ve bought a new home. Both get the same care over preparation. We’re often asked to deal with frame joints opening as the plaster dries and sealant applied over dusty or wet surfaces, on windows & doors, skirting & floors and plot handovers.
Shops, offices and commercial units across London have hard-wearing floors with movement joints that need resealing as they wear, and new homes need their plot mastic finished properly before handover, in Erith and beyond.
All of our work is guaranteed for twelve months, and the guarantee is the same wherever you are.
- Place
- Erith (DA8, DA17, DA7)
- Region
- Greater London
- Cover
- 12 months on all our work
- Price
- Quoted before any work starts
- Phone
- 0345 464 0079
- Updated
- 26 October 2026
What new build mastic looks like in Erith
Many of London’s new homes are flats in bigger developments, where snagging may go through the developer or managing agent. The South East is one of the drier parts of the UK, but outside sealant still needs a dry, clean surface, so outdoor work is planned around the forecast.
If you’ve bought a new home near Erith station, the sealant around baths, showers and frames is worth checking in the first year or two.
Erith is about 3 miles north-west of Dartford, in Greater London. Wherever you are in the DA8 postcode area, we can carry out new build mastic at your property. Erith is one of 764 places in Greater London we cover. There’s also a page for London, about 11 miles away.
We cover every part of DA8, DA17 and DA7 for new build mastic. If you need new build mastic at a property on Church Road, Town Square and Erith High Street or anywhere close by, our applicators can take on the job. Other places close to Erith include Northumberland Heath (1 mile south), Bexley Riverside (1 mile south), Belvedere (1 mile north-west), Lessness Heath (1 mile north-west) and Barnehurst (1 mile south). Larger places within reach include London (11 miles west), City of Westminster (14 miles west), Marylebone (14 miles west), St Pancras (13 miles west), Shoreditch (11 miles west) and Walthamstow (11 miles north-west).
Near you in Erith
Around Erith, our work takes us to homes and buildings near Trinity School, The Cross Keys pub and Erith School, among other places. Erith has its own railway station: Erith station. Nearby you’ll also find Erith Museum (within half a mile east) and Erith and District Hospital (under half a mile south-west). The countryside around Erith includes Crossness Nature Reserve.
Common questions in Erith
Is Erith in your area for new build mastic?
Yes, Erith is within the area we cover. Our work covers London and the South East. You can call 0345 464 0079 or send us an email and let us know what needs doing.
Can you help a landlord with a rental near Erith station?
Yes, we work for landlords and letting agents. Just phone 0345 464 0079 or drop us an email and tell us about the property, and we’ll give you a clear quote.
When is the sealant fully cured?
It depends on the product. Before we leave, we’ll tell you the cure time.
Can you do plot mastic on a new development?
Yes. We take on second-fix sealant work across new plots. Good preparation keeps snagging to a minimum.
Do I have to be there?
It depends on the job. For work indoors, someone needs to let us in.
Is there a guarantee?
Yes, always. Each job is guaranteed for twelve months.
What information do you need?
A short description and the location, with photos by email if possible. We’ll ask anything else we need to know.
Can you work on commercial sites?
Yes. Larger jobs can be planned room by room or area by area.
Should I try it myself first?
Too much sealant is as bad as too little. A heavy bead looks messy and copes badly with movement, and the joint depth matters as much as the finish.
Some jobs are best left to a professional: work at height, external movement joints, fire-rated sealant and large areas need the right product, the right access and the right method.
What we can’t put right
We’ll always be straight with you, so here’s what new sealant will not do:
- Deciding who is responsible under a builder’s warranty
- Structural cracks in walls or ceilings
- Broken tiles or a split tray
Not sure which it is? You can call 0345 464 0079 or drop us an email and we’ll tell you honestly before you book.
Joints and surfaces we work on
- Skirting & floors
- Windows & doors
- Kitchens
- Plot handovers
- Bathrooms & en suites
- Show homes
Nearby places to Erith
Also in Erith
Why it’s worth doing now in Erith
DIY kits don’t solve the main problems with new-build sealant: dust, no primer and old sealant left in the joint. Cutting out, cleaning and priming are what make the difference. In a London flat, a failed joint rarely stays your problem alone: water from a shower or window joint can reach the flat below, and gaps in fire-stopping matter to everyone in the building.
We do not show prices on the website, because each job is priced on what it involves. Call for a quick quote and we will talk you through it.
Why Erith clients choose us
- Neat joints and a tidy finish
- A sealant colour to suit the surroundings
- Over 20 years’ experience
- Every job guaranteed for a year
Take a look at our cost guide and what customers say.
When to call us in Erith
Sealant applied onto damp surfaces does not bond well. On a busy site, joints are not always given time to dry.
The problems people generally mention when they call are:
- Smeared, uneven beads picked up at snagging
- Leaking shower tray seals in a new home
- Cracked sealant around new window and door frames
- Gaps between new skirting and floors
As a London address, Erith can be tricky for parking: let us know about parking bays, permits or a driveway.
What to look for in a quote
- Whether the sealant suits the joint
- Whether they seal over old material or remove it
- Who turns up on the day
- How the surfaces are prepared before sealing
How it works
Good joint work is mostly preparation, and we don’t rush it. Joints are cleaned back and dried before anything new goes in. In total, it generally takes a few hours for most snagging lists, longer for a run of plots. For a job in Erith, parking and access are the things to plan: let us know about parking, the floor we will be working on and any lift or shared entrance.
- We start by agreeing which joints are on the list, from the snagging sheet or plot schedule.
- We cut out every bit of the failed or messy sealant.
- Each joint is cleaned of dust and grit, then primed if required.
- We apply a sealant that suits each joint and tool it to a neat finish.
- Finally, each room is checked and you’re given the cure time.
Preparing for the visit
- Move anything stored near the joints
- Mention if the joints have been sealed before
- Let us know about parking restrictions
Get a quote
If you’re in Erith and need new build mastic, ring 0345 464 0079 or email us. Tell us what the problem is and where, and you will get a clear quote before any work starts.
Related advice
Keeping the joints in good condition
Simple care keeps the joints in good condition. We recommend:
- Record problems with dated pictures
- Do not seal over failed sealant yourself
- Watch for new gaps as the house dries out
- Open a window or run the fan after bathing
Watch the joints as the house settles. Hairline gaps can open as timber and plaster dry and can be resealed later.
Report failed sealant to the builder while you’re in the snagging period. After that, putting it right may fall to you so report it promptly.