Greater London · England
New Cross New Build Mastic
Plot mastic for developers and snagging failed sealant in new homes in New Cross, with a 12-month guarantee on every job. Call for a quick quote.
- Sealant applied over dusty or wet surfaces
- Messy sealant that spoils new finishes
- Cracks appearing as a new home settles
How we handle new build mastic in New Cross
Snagging sealant properly means taking the failed bead out completely. New silicone won’t bond to old silicone, so the joint is cut out, cleaned, dried and resealed. We’re often asked to deal with second-fix sealing on new plots and joints pulling apart as timber shrinks, on plot handovers, show homes and bathrooms & en suites.
From brand-new flats to converted terraces with new flooring, London has every kind of floor. Wherever a floor meets a wall, a skirting or a threshold, the joint has to allow for movement.
A 12-month guarantee comes with the work, just as it does everywhere we cover.
- Where
- New Cross (SE8, SE14, SE4)
- Wider area
- Greater London
- Cover
- 12 months on all our work
- Quote
- Quoted before any work starts
- Call
- 0345 464 0079
- Last updated
- 26 October 2026
Can I do it myself?
A careful DIYer can reseal a simple joint, like a short, easy-to-reach joint indoors. The common mistakes are sealing over old sealant, sealing a damp joint and using far too much.
Some jobs are best left to a professional: work at height, external movement joints, fire-rated sealant and large areas call for the right materials, safe access and experience.
Other services in New Cross
What affects the cost of new build mastic
Some jobs are bigger than they look, and some smaller. What affects the quote:
- How easy the joints are to reach
- The size of the job
- How much old sealant there is and how hard it is to remove
- Any mould that needs treating
A few things move the cost up or down: how much old sealant there is and how stubborn it is, whether mould needs treating, and whether we need extra access for height. Your quote takes all of that into account.
Asking for a quote
To make quoting easier, please include:
- Whether it has been sealed before
- The address or postcode of the job
- If it’s domestic, commercial or a hotel
- Pictures of the joints, sent by email
We quote each job on its own, so the first step is telling us about yours. Just call 0345 464 0079 or send us an email with the details and send photos if you have them.
Different surfaces, different methods
Kitchens
Worktop, upstand and sink joints in new kitchens often get a hurried bead. We remove it and reseal with a kitchen-suitable sealant.
Plot handovers
Taking time over preparation reduces return visits. Dust from the build is removed first.
Why act early in New Cross
A quick bead over the top of the old sealant can look fine at first, but it won’t bond to the old layer. A lasting seal starts with removing the old one completely. In a flat in New Cross, failed sealant seldom stays inside your own four walls: water from a shower or window joint can reach the flat below, and gaps in fire-stopping matter to everyone in the building.
The cost depends on the size of the job, how hard the old material is to remove and access to the work. You’ll have a clear quote before any work starts.
Why us?
- One-year guarantee on every job
- Anti-fungal silicone where joints get wet
- We leave the area clean and tidy
- Colour picked to suit the job
Read our cost guide and what customers say.
When it isn’t the sealant
Before booking, it’s worth knowing the limits:
- Deciding who is responsible under a builder’s warranty
- Leaking fittings rather than failed sealant
- Settlement cracks that need a surveyor
If in doubt, phone 0345 464 0079 or drop us an email and we’ll say what we think.
Joints and surfaces we work on
- Skirting & floors
- Show homes
- Windows & doors
- Bathrooms & en suites
- Kitchens
- Plot handovers
New homes and floors in New Cross
Many of London’s new homes are flats in bigger developments, where snags may need reporting through the developer or the managing agent. Rainfall in the South East is lower than in much of the UK, but outside sealant still needs a dry, clean surface, so outdoor work is planned around the forecast.
As a London address, New Cross can be tricky for parking: tell us about permits, visitor bays or off-street space when you book.
New Cross is about 3 miles south-east of London, in Greater London. Every kind of property in New Cross is covered for new build mastic, old or new, large or small. The work is guaranteed for a year. We cover 764 towns and villages across Greater London.
All of SE8, SE14 and SE4 is within our area for new build mastic. If you need new build mastic at a property on Ivy Road, Mona Road and Avon Road or anywhere close by, our applicators can take on the job. New Cross is on the A2209 and A2210, so it’s easy for us to get to with everything needed for new build mastic. Neighbouring places we cover for new build mastic include St Johns (1 mile east), Telegraph Hill (1 mile south-west), Deptford (1 mile north-east), Nunhead (1 mile south-west) and Lewisham (1 mile south-east). Further out, we also cover London (3 miles north-west), City of Westminster (6 miles north-west), Marylebone (6 miles north-west), Kensington (8 miles west), St Pancras (5 miles north-west) and Shoreditch (4 miles north-west).
Near you in New Cross
We work in homes and buildings around Wickham Arms, Fordham Park and Addey and Stanhope School, among other places. You’ll also find St. Paul's (0.7 miles north-east) and Laban Centre (0.9 miles north-east). New Cross has its own railway station: New Cross station. Other landmarks nearby include Fan Museum (1.2 miles north-east) and Greenwich Castle (1.5 miles east). Green spaces nearby include St. James's Park Lake and Tower Hill.
New Cross: your questions answered
Can you help a landlord with a rental near New Cross station?
Yes. We work for landlords and letting agents as well as householders, and several properties can go on one quote. You can ring 0345 464 0079 or send us an email with the details for a clear quote.
Is New Cross in your area for new build mastic?
Yes. Our work covers London and the South East, and New Cross is part of that. Just ring 0345 464 0079 or drop us an email with a few details of the job.
Will it make a mess?
Very little: the area around the joints is protected first, and we tidy up before we go.
When is the best time to reseal in a new build?
It depends on whether water is getting through. A leaking shower or bath seal should be redone straight away, while small cosmetic gaps can wait a while.
Can I do it myself?
You can, for simple jobs. The key is preparation: remove all the old material and work on a clean, dry joint. We can always put it right if it fails.
What do you need from me for a quote?
A short description and the location. If we need more, we’ll ask.
What colour sealant will you use?
We use white, clear or a colour to suit the finishes. Tell us what you’d like when you get a quote.
Can you work on commercial sites?
Yes. We’ve worked for hotels, offices and other businesses, and we’re fully insured.
Do you need new build mastic in New Cross?
Sealant applied onto damp surfaces doesn’t bond well. Site programmes do not always leave time for joints to dry.
Any of these means the joints need attention:
- Joints pulling apart as timber shrinks
- Untidy sealant flagged on a snagging list
- Internal frame sealant that has split
- Cracked caulk along new skirting
If you’ve bought a new home near New Cross station, the sealant around baths, showers and frames is worth checking in the first year or two.
What to look for in a quote
- What preparation is included
- What the cure time is
- What product goes in the joint
- What the quote includes, VAT included or not
How it works
On the day, we look over the joints with you first, so there are no surprises. Surfaces next to the work are protected before any work begins. The work normally takes a few hours in a single home. Parking in much of London is by permit or pay-and-display, so it helps to know what’s near you in New Cross. It helps if you can point us to a visitor permit or a bay close to the door.
- Each joint is checked for movement before any work starts.
- We remove the failed sealant and clean the joints.
- Joints are dried and primed where the product calls for it.
- Baths are filled with water, then the new sealant is applied.
- We check every joint and leave you with the cure times.
How to prepare
- Move anything stored near the joints
- Let us know about stairs, lifts or work at height
- Try not to wet indoor joints just before the visit
Get a quote
We don’t publish a price list, as no two jobs are quite the same. Instead, we give you a clear quote for your job. To arrange one, phone 0345 464 0079 or drop us an email.