Greater London · England
St Ann's New Build Mastic
We cover St Ann's for plot mastic for developers and snagging failed sealant in new homes. Old material cut out, joints cleaned and sealed neatly.
- Joints pulling apart as timber shrinks
- Cracked sealant around new window and door frames
- Sealant that never bonded to the surface
Landlords, agents and businesses in St Ann's
Landlords and agents in St Ann's can book us as well as homeowners. Sealant work between tenants is a simple way to keep a property in good order before the next move-in.
Letting agents often deal with us directly. Send the address, what’s needed and the access arrangements and we will quote.
New build mastic in St Ann's, done properly
We carry out plot mastic and second-fix sealing for builders, and snagging reseals for new-home owners. In both, preparation makes the difference, because that’s what rushed new-build sealant normally lacks. We work on windows & doors, plot handovers and kitchens, and people most often call us about second-fix sealing on new plots and gaps opening as the house dries out and settles.
Much of London’s new housing is flats in larger developments. Snagging there often goes through the developer or managing agent, and failed shower seals, open skirting joints and gaps at thresholds are typical.
All our work comes with our one-year guarantee, wherever you are in Greater London.
- Place
- St Ann's (N15, N4, N16)
- Region
- Greater London
- Cover
- 12 months on all our work
- Quote
- A clear price before we start
- Phone
- 0345 464 0079
- Updated
- 26 October 2026
Why act early in St Ann's
Running a new bead over the builder’s sealant might look tidy for a few weeks, but it will not bond to the old layer. A lasting seal starts with removing the old one completely. In a flat in St Ann's, 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.
What it costs depends on how much there is to do, how much old material has to come out and access to the work. You will have a clear quote before any work starts.
What you get with us
- Old sealant always removed completely
- 180+ five-star Google reviews
- Experience in homes, commercial sites and hotels
- ARBOMaster approved applicator
Take a look at our cost guide and customer reviews.
The process
A visit follows a simple pattern: we check the joints, mask and protect the surrounding surfaces, carry out the job and clear up. It generally takes anything from a few hours to several days, depending on the number of plots. In St Ann's, flats, stairs and shared entrances are part of the routine. Mention any building rules, key holders or managing agents when you book.
- 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.
- Baths are filled with water, then the new sealant is applied.
- The finished joints are checked and the cure times given.
Preparing for the visit
- Mention any sign-in or site rules at work premises
- Where the joints are inside, avoid wetting them before we arrive
- Tell us about access, such as stairs, a lift or high-level joints
Get a quote
For a quick quote, get us on the phone, or email us if that is easier. Describe what needs sealing and we’ll talk you through the work before giving you a price.
Related advice
Also near St Ann's
Also in St Ann's
How to look after the new joints
After the cure time, these simple habits help:
- Keep water off fresh sealant until it has cured
- Use the extractor fan every time you shower
- Look at the sealant regularly in the first couple of years
- Avoid scourers and strong chemicals on sealant
Watch the joints as the house settles. Small gaps can appear as the house dries and can be resealed later.
Leave a failed new-build seal and water can reach the floor and the ceiling below. Catching it early keeps the fix to the sealant.
What affects the cost of new build mastic
For a quick quote, just ask. The main things that affect it are:
- How many rooms, windows or areas are involved
- Working hours on commercial sites
- Any mould that needs treating
- Which sealant suits the joint
Leaving a failed joint usually makes the job bigger, not smaller, because water and mould keep working on it. If you are unsure, phone 0345 464 0079 or drop us an email for an honest opinion and a quote.
What to tell us for a quote
A few details help us give you an accurate quote. When you get in contact, it helps to mention:
- A few photos by email, if you can
- The type of property
- Access, such as stairs, a lift or height
- Roughly how big the job is
Getting a quote is simple: tell us what needs doing and where. A few pictures by email make the job easier to understand, and we’ll take it from there.
When to call us in St Ann's
Baths and trays settle under load once the home is lived in. If a bath wasn’t filled when it was sealed, the bead is stretched the first time it’s used and the sealant may split.
Common reasons people contact us are:
- Smeared, uneven beads picked up at snagging
- Internal frame sealant that has split
- Worktop and upstand sealant coming away
- Gaps opening as the house dries out and settles
If you’ve bought a new home near Seven Sisters station, the sealant around baths, showers and frames is worth checking in the first year or two.
What to look for in a quote
- How hidden problems are handled
- Is VAT in the price?
- Whether the sealant suits the joint
- How the surfaces are prepared before sealing
St Ann's: your questions answered
Is parking a problem for a job in St Ann's?
Parking in St Ann's, as in most of London, takes a little planning: a visitor permit or a bay close to the door helps a lot, so mention what’s available when you book.
I let a flat near Seven Sisters station. Can you help?
Yes, landlords and agents are among the people we work for. You can ring 0345 464 0079 or send us an email with the details for a clear quote.
Do you have insurance?
Yes. We are fully insured, with over 20 years’ experience in sealant work.
How long will you be here?
Typically it takes a few hours in a single home. Bigger jobs take longer, and we will say how long yours will take.
Do you come to St Ann's?
Yes. We cover St Ann's and the rest of Greater London, as part of our work across South East England, London and Scotland. To book, phone 0345 464 0079 or drop us an email.
Do you work through snagging lists?
Yes. Snagging lists are a common starting point for us. We’ll go through the sealant items and agree what we’ll do.
What does new build mastic cost?
We don’t publish prices, because the cost depends on the job: its size, the old material, access and the product needed. We agree the price before any work begins.
Do you take out the old sealant first?
Yes. Sealing over old sealant is the main reason resealing fails early, and it’s something we never do.
New build mastic in St Ann's: local notes
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. Many of London’s new homes are flats in bigger developments, where snags may need reporting through the developer or the managing agent.
St Ann's is in London, so parking needs planning: let us know about parking bays, permits or a driveway.
St Ann's is about 2 miles north-west of West Hackney, in Greater London. Anywhere in N15, we cover new build mastic for homes and businesses. Our Greater London coverage runs to 764 places, St Ann's among them. For nearby work, see our London page (6 miles or so).
Our applicators cover all of N15, N4 and N16 for new build mastic. If you need new build mastic at a property on Ida Road, Elmar Road and Grove Road or a nearby road, we can help. Neighbouring places we cover for new build mastic include West Green (1 mile north-west), Seven Sisters (1 mile east), South Tottenham (1 mile east), Harringay (1 mile west) and Tottenham Green (1 mile north-east). Larger places within reach include London (6 miles south), City of Westminster (5 miles south-west), Marylebone (5 miles south-west), Kensington (8 miles south-west), St Pancras (4 miles south) and Shoreditch (4 miles south).
Local landmarks in St Ann's
Around St Ann's, our work takes us to homes and buildings near Church of St Andrew, No.8 Seven Sisters pub and Moselle Upper School, among other places. You’ll also find Chestnuts Park (under half a mile west) and Park View School (0.5 miles north-west). St Ann's has its own railway station: Seven Sisters station. Other landmarks nearby include City of London Maternity Hospital (1.7 miles south-west) and The Mall Wood Green (1.4 miles north-west). Not far away are Railway Fields and Hollow Pond.
What the job involves on each surface
Skirting and floors
Wet-area floor joints need a flexible seal. We seal them with a sealant suited to wet areas.
Kitchens
Worktops in new homes can move slightly as the house dries, opening gaps behind the upstand. A fresh flexible bead closes them.