Greater London · England
New-build mastic & snagging in The Wrythe, Greater London
New build mastic for The Wrythe, by sealant specialists with 20+ years’ experience. 180+ five-star Google reviews and a 4.9 rating.
- Sealant applied over dusty or wet surfaces
- Untidy sealant flagged on a snagging list
- Leaking shower tray seals in a new home
New build mastic for homes and businesses in The Wrythe
Our new-build work comes in two parts: plot mastic for developers, and putting right failed sealant for people who’ve bought a new home. In both, preparation makes the difference since hurried prep is behind a lot of new-build failures. If you are dealing with skirting joints opening in the first winter and internal frame sealant that has split, we can put it right, on skirting & floors, bathrooms & en suites and kitchens alike.
Much of London’s new housing is flats in larger developments. In a new development, snags are often reported through the developer or the managing agent, and failed shower seals, open skirting joints and gaps at thresholds are typical.
The work is covered for a year after we finish. If anything is not right with it, call 0345 464 0079 or email us.
- Where
- The Wrythe (SM5, SM6, SM1)
- Wider area
- Greater London
- Cover
- One year on every job
- Quote
- A clear price before any work starts
- Call
- 0345 464 0079
- Updated
- 26 October 2026
Why it’s worth doing now in The Wrythe
The builder is normally the first port of call while the snagging or warranty period runs. If it’s slow, or the same joint keeps failing, a proper reseal from a specialist is the next step. In a flat in The Wrythe, 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. We give a clear quote before any work starts, so you know where you stand.
Why book with us
- You choose the colour before work begins
- Domestic, commercial and hotel work
- White, clear, grey or coloured to suit, where the product allows
- Full insurance on every job
See what affects the cost and what customers say.
Places near The Wrythe
What else we do in The Wrythe
What happens on the day
We work through the job in order: protection first, then preparation, sealing and a tidy-up. For most jobs that takes anything from a few hours to several days, depending on the number of plots and we leave things clean and tidy. Parking in much of London is by permit or pay-and-display, so it helps to know what’s near you in The Wrythe. 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.
- Joints are dried and primed where the product calls for it.
- 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.
Getting ready for the visit
- Mention any sign-in or site rules at work premises
- Mention any parking rules near the property
- Mention any leaks or damp you’ve noticed
Getting a quote
Asking for a quote is easy: tell us what needs doing and where and its rough size. Photos by email help us understand the job, and we will come back to you with a quote.
Related advice
What new build mastic looks like in The Wrythe
Much of London’s new housing is flats in larger developments, where snagging may go through the developer or managing agent. The South East is one of the drier parts of the UK, but outside sealant still needs a dry, clean surface, so outdoor work is planned around the forecast.
The Wrythe is in London, so parking needs planning: let us know about parking bays, permits or a driveway.
The Wrythe is about 7 miles south of Stockwell, in Greater London. Homes, rented property, offices and hotels in The Wrythe is covered for new build mastic. Every job comes with our 12-month guarantee. Our Greater London coverage runs to 764 places, and The Wrythe is one of them. London is on our list too, about 9 miles from The Wrythe.
We work across the SM5, SM6 and SM1 postcode area for new build mastic and the streets around it. We cover properties on Elm Road, Byne Road and Mill Lane. Other places close to The Wrythe include Carshalton (1 mile south), Wallington (1 mile south-east), Rosehill (1 mile north-west), St Helier (1 mile north-west) and Benhilton (1 mile west). Within a short drive, we also cover London (9 miles north), City of Westminster (10 miles north), Marylebone (10 miles north), Kensington (9 miles north), St Pancras (11 miles north) and Shoreditch (11 miles north).
Landmarks near The Wrythe
Around The Wrythe, our work takes us to homes and buildings near Carshalton Park, The Railway Tavern and Carshalton High School for Girls and the streets around them. The Wrythe has its own railway station: Carshalton station. Nearby you’ll also find Centrale Croydon (2.7 miles east) and Honeywood Museum (0.6 miles south). Not far away are The Spinney Local Nature Reserve and Duppas Hill.
When to call us in The Wrythe
On many sites, sealant goes on in the final rush before handover. Joints aren’t always cleaned of dust or primed, and the sealant sits on grit instead of the surface.
Keep an eye out for these signs:
- Kitchen sealant that has pulled off the wall
- Cracked sealant around new window and door frames
- Joints pulling apart as timber shrinks
- Sealant that never bonded to the surface
For new homes near Carshalton station, it’s worth checking the sealant early, while snags are still fresh.
What to look for in a quote
- Is VAT in the price?
- Which colour the sealant will be
- How the surfaces are prepared before sealing
- What product goes in the joint
DIY versus a professional finish
A DIY attempt doesn’t rule out a professional job. We remove it and do the joint properly.
Sealing over old silicone is the commonest DIY error. New silicone won’t bond to old, so it lifts and traps water and mould underneath. Everything old must be removed first.
Looking after it afterwards
Once the sealant has cured, a few habits help it last:
- Look at the sealant regularly in the first couple of years
- Do not wait for the house to settle if water is getting through
- Open a window or run the fan after bathing
- Put sealant faults on your snagging list early
Clean the sealant with a mild detergent and a soft cloth. Avoid abrasive pads and strong solvents, which can damage the surface.
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.
Quotes for new build mastic in The Wrythe
You will get a clear quote before any work starts. It takes into account:
- Whether there’s mould to deal with
- How many rooms, windows or areas are involved
- The old material and how stubborn it is
- How easy the joints are to reach
Combining jobs into one visit is normally more efficient than separate visits. We’ll give you a clear quote for the lot.
Asking for a quote
When you contact us, these details help:
- Whether it’s a home or a business
- Access, such as stairs, a lift or height
- Whether it has been sealed before
- Photos by email, if that is easy
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.
Work for landlords, hotels and businesses
We work for landlords and letting agents as well as householders. Sealant work between tenants keeps a property looking cared for before the next move-in.
A neglected joint can let water reach the structure, which is a bigger problem in a rented property. Keeping joints in good order is simple maintenance that we can handle for you.
The Wrythe: your questions answered
Can you do new build mastic in The Wrythe?
Yes, The Wrythe 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.
Can you help a landlord with a rental near Carshalton station?
Yes, landlords and agents are among the people we work for, and several properties can be quoted together. You can ring 0345 464 0079 or drop us an email with the details for a clear quote.
What sealant do you use?
It depends on the joint: anti-fungal sanitary silicone in wet areas, and other sealants where joints move or face the weather. Brands we use include Arbo and Everbuild.
Is it normal for sealant to crack in a new home?
There are usually two causes: the house moving as it dries, and sealant that never bonded properly. Cutting it out and resealing properly fixes both.
Do you remove the old sealant?
Yes. We cut out all the old sealant and clean the joint.
Do I have to be there?
It depends on the job. Inside work needs someone to give us access.
Who should fix failed sealant in a new build?
If you’re still within the builder’s snagging or warranty period, report it to them first. If it is not sorted, or keeps failing, get in touch with us.
Can you do several jobs on one visit?
Yes, and it often makes sense. Doing several areas at once is generally more efficient, so mention them when you ask for a quote.