Greater London · England
New-build mastic & snagging in Blackheath, Greater London
Problem with your new-build sealant joints in Blackheath? We cut out the old, prepare the joints and apply the right sealant.
- Skirting joints opening in the first winter
- Sealant applied over dusty or wet surfaces
- Gaps behind new kitchen upstands
Landlords, agents and businesses in Blackheath
In hotels, rooms out of use cost money, so we plan the work room by room around your bookings where we can. We’ve worked in hotels as well as homes and businesses.
We work for landlords and letting agents as well as householders. Resealing between tenancies keeps a property looking cared for.
How we handle new build mastic in Blackheath
Across Blackheath, we work for both new-home owners and the builders handing those homes over. Whether it’s one en suite or a run of plots, the method is the same: remove, clean, prime where needed, then a neat new bead. We work on show homes, kitchens and plot handovers, and people most often call us about frame joints opening as the plaster dries and sealant applied over dusty or wet surfaces.
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.
We stand behind the work with a 12-month guarantee, so you are not left on your own once the job is done.
- Location
- Blackheath (SE3, SE13, SE10)
- Region
- Greater London
- Cover
- One year on every job
- Price
- Quoted before any work starts
- Telephone
- 0345 464 0079
- Last updated
- 26 October 2026
Blackheath questions
Can you help a landlord with a rental near Blackheath station?
Yes, we work for letting agents and landlords. Just ring 0345 464 0079 or drop us an email and tell us about the property, and we’ll give you a clear price.
Do you cover Blackheath for new build mastic?
Yes, Blackheath is within the area we cover. Our work covers London and the South East. You can ring 0345 464 0079 or drop us an email and let us know what needs doing.
Will you just run a new bead over the existing one?
No. Sealing over old sealant looks fine for a few weeks, then lifts. All the old sealant comes out before any work starts.
Should I go to my builder first?
If you’re still within the builder’s snagging or warranty period, report it to them first. If they’re slow or the fix does not last, we can help.
Are you insured?
Yes, we are fully insured for every job we do.
Can I send you my snagging list?
Yes. Photos of each sealant item help us quote. Items that need a plumber, tiler or the builder are flagged.
Do you guarantee your work?
Yes, for a year. If there’s a problem with our work in that time, tell us and we’ll put it right.
Can you quote for more than one area?
Yes. More than one area can go on one quote.
Towns and villages near Blackheath
Other services in Blackheath
New build mastic around Blackheath
Much of London’s new housing is flats in larger 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, though outdoor sealant still has to go onto a dry joint, so the forecast decides the day.
Blackheath is in London, so parking needs planning: tell us about permits, visitor bays or off-street space when you book.
Blackheath is about 1 mile south-east of Greenwich, in Greater London. From the centre of Blackheath to the outskirts, new build mastic is available for homes and businesses alike. Blackheath is one of 764 places in Greater London we cover for new build mastic.
We work across SE3, SE13 and SE10 for new build mastic and the streets around it. You’ll find streets such as Pond Road, Heath Lane and Wemyss Road, and we cover them all. Other places close to Blackheath include Vanbrugh Park Estate (1 mile north), Greenwich (1 mile north-west), Maze Hill (1 mile north), Lewisham (1 mile south-west) and Westcombe Park (1 mile north-east). Within a short drive, we also cover London (5 miles north-west), City of Westminster (8 miles north-west), Marylebone (7 miles north-west), Kensington (9 miles west), St Pancras (7 miles north-west) and Shoreditch (5 miles north-west).
Landmarks near Blackheath
In Blackheath, that means homes and buildings near The Princess Of Wales Pub, Blackheath Proprietary School and Manor House Gardens. Blackheath has its own railway station: Blackheath station. Other landmarks nearby include Lewisham Shopping Centre (1.1 miles south-west) and Royal Observatory (0.7 miles north-west). For a walk, there’s Tower Hill and Birdbrook Road Nature Reserve.
Different surfaces, different methods
Plot handovers
Developers can send the plot schedule and specification. We seal bathrooms, kitchens, frames and floors as agreed.
Skirting and floors
Floors and skirting move as the house dries and the heating runs. Caulk cracks; a flexible sealant moves with it in a colour to suit.
When to call us in Blackheath
A new house holds a lot of water from the build, which takes a year or two to dry out. As it does, timber shrinks and joints open, and sealant that can’t keep up splits.
It’s worth asking for a quote if you see:
- Beads laid onto grit and dust from the build
- Cracked caulk along new skirting
- Kitchen sealant that has pulled off the wall
- Cracked sealant around new window and door frames
For new homes near Blackheath station, it’s worth checking the sealant early, while snags are still fresh.
Questions to ask before you book
- When the joint can take water or movement
- What guarantee comes with the work
- How the surfaces are prepared before sealing
- Who does the work, and how experienced they are
Quotes for new build mastic in Blackheath
The quote reflects the job in front of us. We take into account:
- How many rooms, windows or areas are involved
- Whether the work is at height
- The size of the job
- The old material and how stubborn it is
Some things make a job bigger or smaller: how much old sealant there is and how stubborn it is, whether mould needs treating, and whether the work is at height. Your quote takes all of that into account.
What to tell us for a quote
There’s no need for technical detail. It helps if you can tell us:
- Where the property is
- How we’d reach the joints
- The rough size of the job
- If someone has resealed it before
Quotes start with a quick conversation. Tell us what’s wrong, where it is and how much there is, and we’ll explain how we’d tackle it. Whenever you are ready, phone 0345 464 0079 or send us an email.
Can I do it myself?
Sealing over old silicone is the commonest DIY error. Silicone does not stick to old silicone, so it lifts and traps water and mould underneath. All the old material has to come out first.
A careful DIYer can reseal a simple joint, like a short, easy-to-reach joint indoors. Where it goes wrong is sealing over the old bead, working on a wet joint or overloading the gap.
Why deal with it now?
Running a new bead over the builder’s sealant might look tidy for a few weeks, but it can’t bond to what’s underneath. A lasting seal starts with removing the old one completely. In London conversions, one flat’s bathroom is often above another flat’s ceiling, and a slow leak from a failed seal can end up in the flat below. Putting it right early is much less trouble for homes in Blackheath.
We don’t show prices on the website, because the cost depends so much on the job itself. For a quick quote, please call 0345 464 0079 or email us and we will talk you through it.
Why Blackheath customers choose us
- We never seal over old sealant
- We leave the area clean and tidy
- 20+ years of sealant experience
- Quality sealants from Arbo and Everbuild
Read what affects the cost or what customers say.
The process
On the day, there’s very little for you to do. Show us the job and we will take it from there. The job generally takes anything from a few hours to several days, depending on the number of plots from start to finish. In Blackheath, as in most of London, parking needs a little planning. A visitor permit or a nearby bay makes the visit run more smoothly.
- 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.
- Surfaces are cleaned of building dust and primed where needed.
- New sealant suited to each joint is applied and tooled neatly.
- Finally, each room is checked and you’re given the cure time.
Getting ready for the visit
- Tell us if parking is tricky
- For indoor joints, keep the area dry beforehand if you can
- Mention any tricky access
Get a quote
Need a quote? Please ring 0345 464 0079 or drop us an email and tell us about the job. We will explain what we’d do and give you a clear price before we start.