Greater London · England
New-build mastic & snagging in St Paul's Cray, Greater London
Professional new build mastic in and around St Paul's Cray, with every bit of old sealant taken out first.
- Beads laid onto grit and dust from the build
- Plot mastic for developers ahead of handover
- Frame joints opening as the plaster dries
New build mastic in St Paul's Cray, done properly
Some new-home owners let the house settle before resealing. For small cosmetic gaps, that’s reasonable, but a seal that’s letting water through needs doing now. We work on skirting & floors, plot handovers and windows & doors, and the jobs we see most are joints pulling apart as timber shrinks and gaps behind new kitchen upstands.
Across London, commercial floors have movement joints that break down under heavy foot traffic, while new homes need a neat, sound finish around frames, baths and kitchens before handover, in St Paul's Cray and beyond.
The work is covered for a year after we finish. If anything is not right with it, ring 0345 464 0079 or email us.
- Location
- St Paul's Cray (BR5, BR7)
- Wider area
- Greater London
- Cover
- A year, on every job
- Quote
- A clear quote up front
- Call
- 0345 464 0079
- Updated
- 26 October 2026
Keeping the joints in good condition
Simple care keeps the joints in good condition. Our advice:
- Use the extractor fan every time you shower
- Raise failed sealant with the developer while you’re covered
- Don’t wait for the house to settle if water is getting through
- Avoid scourers and strong chemicals on sealant
Keep photos of the joints and any snagging correspondence with your builder. It helps if anything else comes up during the warranty period.
A failed seal in a new home lets water into joists, plasterboard and ceilings. Catching it early keeps the fix to the sealant.
Common questions in St Paul's Cray
Can you help a landlord with a rental near St Mary Cray station?
Yes, we work for landlords and letting agents. Just ring 0345 464 0079 or send us an email and tell us about the property, and we will send you a clear quote.
Is St Paul's Cray in your area for new build mastic?
Yes. We work across London and the South East, and St Paul's Cray is part of that. Just phone 0345 464 0079 or send us an email with a few details of the job.
Why has my new-build shower seal failed already?
A new house dries and settles for a year or two, and sealant is often applied quickly onto dusty surfaces. Either can make it fail early.
Is there a guarantee?
Yes, for a year. If anything isn’t right with the work within the year, let us know and we will sort it.
How long does new build mastic take?
A typical job takes a few hours for most snagging lists, longer for a run of plots. Your quote will say how long we expect yours to take.
What does new build mastic cost?
Size, access and the old material all affect the cost. Ask us for a quote and we’ll talk you through it.
What colour sealant will you use?
The colour is chosen to suit the tiles, worktop or frame. Let us know your preference when you ask for a quote.
Is it worth resealing while the house is still settling?
It depends on whether water is getting through. A leaking shower or bath seal should be redone right away, but cosmetic gaps can wait for movement to slow.
Should I try it myself first?
The biggest DIY mistake is sealing over old sealant. New silicone won’t bond to old, so it peels away and traps moisture behind it. Everything old must be removed first.
A DIY attempt does not rule out a professional job. We remove it and do the joint properly, so tell us about it when you ask for a quote.
Why it’s worth doing now in St Paul's Cray
Water getting past a failed seal in a new build reaches walls and floors that are still settling. Resealing promptly protects the new finishes around it. 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.
A few things move the cost up or down: the old material and how easily it comes out, any mould to treat, and whether we need extra access for height. We take all of that into account in your quote.
Why St Paul's Cray clients choose us
- Domestic, commercial and hotel work
- Quality sealants from Arbo and Everbuild
- White, clear, grey or another colour, product permitting
- 4.9 on Google from 180+ five-star reviews
The process
There isn’t much for you to do on the day. Show us the job and we’ll take it from there. The work itself takes a few hours for most snagging lists, longer for a run of plots from start to finish. In St Paul's Cray, flats, stairs and shared entrances are part of the routine. If the building has a concierge, managing agent or access rules, tell us when you book.
- Each joint is checked for movement before we start.
- We remove the failed sealant and clean the joints.
- We make sure the joints are dry and prime them if needed.
- Baths are filled with water, then the new sealant is applied.
- The finished joints are checked and the cure times given.
How to prepare
- Keep children and pets away from the work area
- Try not to wet indoor joints just before the visit
- Let us know about earlier repairs to the joints
Get a quote
Getting a quote is simple: tell us what needs doing and where and its rough size. Photos by email help us understand the job, and we will take it from there.
Read more
Different surfaces, different methods
Show homes
In a show home, the sealant is on display. Every bead is neat and coloured to suit the room.
Bathrooms and en suites
Shower trays in new homes often move slightly in the first year. We reseal once the old bead is fully out with baths filled first.
Joints and finishes in St Paul's Cray homes
Compared with the north and west, the South East gets less rain, but outside sealant still needs a dry, clean surface, so outdoor work is planned around the forecast. Much of London’s new housing is flats in larger developments, where snagging may go through the developer or managing agent.
St Paul's Cray is in London, so parking needs planning: tell us about permits, visitor bays or off-street space when you book. For new homes near St Mary Cray station, it’s worth checking the sealant early, while snags are still fresh.
St Paul's Cray is about 1 mile north of Orpington, in Greater London. Across the BR5 area, our applicators can take on new build mastic. Our area takes in 764 places across Greater London, large and small. For nearby work, see our London page.
Work in BR5 and BR7 is quoted and booked the same way as anywhere else. If you need new build mastic at a property on Main Road, Murray Road and Rushet Road or anywhere close by, our applicators can take on the job. If you’re just outside St Paul's Cray, we cover St Mary Cray (1 mile south), Poverest (1 mile south), Derry Downs (1 mile south), Orpington (1 mile south) and Kevington (2 miles south-east). Further out, we also cover London (11 miles north-west), City of Westminster (14 miles north-west), Marylebone (14 miles north-west), Kensington (15 miles north-west), St Pancras (13 miles north-west) and Shoreditch (12 miles north-west).
What’s near St Paul's Cray
Around St Paul's Cray, our work takes us to homes and buildings near Kemnal Technology College, The Blue Anchor Public House and Walsingham School, among other places. St Paul's Cray has its own railway station: St Mary Cray station. Nearby you’ll also find Lullingstone Castle (4.8 miles south-east) and London Borough of Bromley Museum (1.5 miles south). Not far away are The Warren and Summer Hill.
Landlord and commercial work in St Paul's Cray
From a single let to a portfolio, you get the same standard of work: old sealant fully removed, joints prepared properly and a 12-month guarantee.
Housing providers, facilities teams and property managers book us too. Several sites can be quoted together, and we are fully insured.
Nearby places to St Paul's Cray
More services for St Paul's Cray
What affects the cost of new build mastic
For a quick quote, just ask. What matters most is:
- Working hours on commercial sites
- Access and height
- The size of the job
- The product the joint needs
What it costs depends on the amount of work, how much old material has to come out and access to the work. You will have a clear quote before any work starts, so you know where you stand.
Helping us quote
To help us quote quickly, let us know:
- How we’d reach the joints
- What’s wrong with the joints now
- Whether it’s a home or a business
- How many joints, rooms or windows are involved
Need a quote? Please call 0345 464 0079 or drop us an email with a few details. We will explain what we’d do and give you a clear price before work begins.