Greater London · England
New Build Mastic in Blackfriars
Professional new build mastic in and around Blackfriars, with old sealant always removed completely and a 12-month guarantee.
- Worktop and upstand sealant coming away
- Sealant work across a run of new homes
- Skirting joints opening in the first winter
New build mastic in Blackfriars, done properly
Across Blackfriars, we work for both new-home owners and the builders handing those homes over. One shower or a whole phase of plots, the method doesn’t change: cut out, clean, prime where needed and reseal neatly. If you have new-build shower sealant that has already split and gaps opening as the house dries out and settles, we can help, on plot handovers, kitchens and skirting & floors alike.
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.
The work is covered for a year after we finish. If anything is not right with it, call 0345 464 0079 or send us an email.
- Place
- Blackfriars (SE1, EC1M, EC1N)
- Wider area
- Greater London
- Cover
- A year, on every job
- Price
- A clear quote up front
- Telephone
- 0345 464 0079
- Page updated
- 26 October 2026
Joints and finishes in Blackfriars homes
Much of London’s new housing is flats in larger developments, where snags may need reporting through the developer or the managing agent. Compared with the north and west, the South East gets less rain, yet outdoor joints still have to be sealed dry, so jobs are booked with the weather in mind.
If you’ve bought a new home near London Blackfriars station, the sealant around baths, showers and frames is worth checking in the first year or two.
Blackfriars is about 1 mile north-west of London, in Greater London. We carry out new build mastic for householders, landlords and businesses in Blackfriars and nearby, as part of our work across Greater London. Our Greater London coverage runs to 764 places, and Blackfriars is one of them.
Here we cover the SE1, EC1M and EC1N postcode area for new build mastic. You will find streets such as Oat Lane, Bear Lane and Shoe Lane, and we cover them all. Blackfriars sits on or near the A4 and A40, which makes travel easy. We also cover the places around Blackfriars: Temple (1 mile west), Temple Bar (1 mile west), Bankside (1 mile south-east), Smithfield (1 mile north) and Clare Market (1 mile west). Larger places within reach include Kensington (4 miles west), Walthamstow (6 miles north-east), Hampstead (4 miles north-west), Ruislip (14 miles west), Brompton (3 miles south-west) and Stockwell (3 miles south).
Landmarks near Blackfriars
Typical jobs here are in homes near Barts Health Archives, St Mary-at-Hill and St Alban's Church of England Primary School. You’ll also find Bernie Spain Gardens (less than half a mile south-west), London Nautical School (0.5 miles south-west) and The Black Friar pub (within half a mile south-east). There’s a railway station in Blackfriars itself: London Blackfriars station. Nearby you’ll also find Montfichet's Tower (under half a mile north-east) and St Brides Crypt Museum (under half a mile north-west). Open spaces near Blackfriars include Barnsbury Wood and St. James's Park Lake.
Aftercare tips
A little care helps the new joints last. We recommend:
- Act quickly if a seal starts to leak
- Keep pictures and emails about snagging items
- Look at the sealant regularly in the first couple of years
- Keep water off fresh sealant until it has cured
Photograph failed sealant before it’s redone and keep the builder’s replies. It’s useful if you need to raise other issues later.
The sooner you deal with untidy or cracking sealant, the less there is to put right. Left alone, a small crack can become a leak over time.
Also near Blackfriars
Other services in Blackfriars
When something else is needed
We will always be straight with you, so here’s what new sealant won’t do:
- Disputes or warranty claims with your builder
- Baths and trays that move too much for sealant to cope with
- Leaks from pipes, valves or wastes, which need a plumber
If in doubt, ring 0345 464 0079 or drop us an email and we will say what we think.
Surfaces we seal
- Skirting & floors
- Kitchens
- Show homes
- Plot handovers
- Windows & doors
- Bathrooms & en suites
Signs you need new build mastic in Blackfriars
A new house holds a lot of water from the build, and it dries out over the first couple of years. As it does, timber shrinks and joints open and the sealant has to cope with the movement.
Most people get in touch when they notice something like this:
- New-build shower sealant that has already split
- Messy sealant that spoils new finishes
- Sealant applied over dusty or wet surfaces
- Gaps between new skirting and floors
As a London address, Blackfriars can be tricky for parking: tell us about permits, visitor bays or off-street space when you book.
Before you book anyone
- Which sealant they’ll use, and why
- Who does the work, and how experienced they are
- What the cure time is
- Whether they seal over old material or remove it
What we do, step by step
There isn’t much for you to do on the day. Show us the job and we will take it from there. The work itself takes anything from a few hours to several days, depending on the number of plots, including the tidy-up. Parking in much of London is by permit or pay-and-display, so it helps to know what’s near you in Blackfriars. It helps if you can point us to a visitor permit or a bay close to the door.
- We look at why each joint failed, including any movement.
- Old sealant is cut out and the joints cleaned.
- We make sure the joints are dry and prime them if needed.
- New sealant goes in, with baths filled first so they’re at their heaviest.
- We check every joint and leave you with the cure times.
Before we arrive
- Tell us if parking is tricky
- Mention any sign-in or site rules at work premises
- Tell us about any water getting in
Get a quote
If you’re in Blackfriars and need new build mastic, phone 0345 464 0079 or email us. A short description of the job and where it is helps us quote, and we will agree the price before any work begins.
Advice
Why it’s worth doing now in Blackfriars
Sealant done properly at handover means fewer callbacks. Snagging visits for failed sealant cost time on every plot and most come down to preparation. Damp from a failed joint spreads quietly in older London brickwork and timber, and once it shows in Blackfriars, the repair is bigger than a sealant job.
Homes and businesses are quoted the same way: the amount of work, the access and the products needed, plus any working-time requirements on site. Call for a quick quote and we’ll explain what it covers.
Why Blackfriars clients choose us
- Sanitary silicone with an anti-fungal additive in wet areas
- White, clear, grey or another colour, product permitting
- ARBOMaster approved applicator
- Tidy, careful work
See what affects the cost or our reviews.
Blackfriars: your questions answered
Can parking be tricky for a visit in Blackfriars?
In much of London, parking needs planning: a visitor permit or a bay close to the door helps a lot.
Can you do new build mastic in Blackfriars?
Yes, Blackfriars is within the area we cover. We work across London and the South East. You can phone 0345 464 0079 or send us an email and tell us what needs doing, and we’ll send you a clear quote.
Do you do commercial work?
Yes. Commercial and hotel work is a large part of what we do. We can talk about working times when we quote.
Is the work guaranteed?
Yes. Each job is guaranteed for twelve months, large or small.
Are you ARBOMaster approved?
Yes. Mr Mastic is an ARBOMaster approved applicator and we’re fully insured too.
Can tenants book the work?
We can work for tenants, landlords or agents. Just make sure your landlord agrees.
Will it make a mess?
No. We protect the surfaces around the joints, and we tidy up before we go.
Do I have to be there?
That depends on where the joints are. Inside work needs someone to give us access, while outside work can sometimes be arranged differently.
Should I try it myself first?
Overfilling a joint is a classic DIY mistake. A thick, smeared bead looks untidy and doesn’t move well, and the joint depth matters as much as the finish.
The biggest DIY mistake is sealing over old sealant. New silicone will not bond to old, so it peels away and traps moisture behind it. All the old material has to come out first.
Quotes for new build mastic in Blackfriars
The price is agreed before any work begins. It’s based on:
- Working hours on commercial sites
- How easy the joints are to reach
- The old material and how stubborn it is
- Whether there’s mould to deal with
What you pay reflects the work, not guesswork. That is why we ask about the job first and agree the price before starting.
What to tell us for a quote
Photos help, but a description is a good start. Please mention:
- What the problem is, such as mould, gaps, leaks or cracking
- Photos by email, if that’s easy
- If it’s domestic, commercial or a hotel
- How we’d reach the joints
Asking for a quote is easy: let us know what needs doing and where. A few photos by email make the job easier to understand, and we’ll take it from there.