Southampton · England
New-build mastic & snagging in St Mary's, Southampton
Plot mastic for developers and snagging failed sealant in new homes for St Mary's, backed by a one-year guarantee. Call for a quick quote.
- Sealant work across a run of new homes
- Sealant that never bonded to the surface
- Leaking shower tray seals in a new home
When it isn’t the sealant
New sealant can’t fix everything, and we’d rather say so up front. Sealant will not put right:
- Structural cracks in walls or ceilings
- Plumbing faults behind the sealant
- Disputes or warranty claims with your builder
If you’re not sure, just ring 0345 464 0079 or drop us an email and we will give you a straight answer before booking.
Where we work in St Mary's
- Plot handovers
- Show homes
- Windows & doors
- Bathrooms & en suites
- Skirting & floors
- Kitchens
New build mastic in St Mary's
We carry out plot mastic and second-fix sealing for builders, and snagging reseals for new-home owners. Both get the same care over preparation since hurried prep is behind a lot of new-build failures. We’re often asked to deal with sealant that never bonded to the surface and worktop and upstand sealant coming away, across skirting & floors, show homes and plot handovers.
For a new home in or near St Mary's, it’s worth checking the sealant early. Gaps at skirtings, shower seals pulling away and missing mastic around frames are common snags.
The work is covered for a year after we finish. If anything isn’t right with it, call 0345 464 0079 or drop us an email.
- Place
- St Mary's (SO14, SO15, SO18)
- Region
- Southampton
- Guarantee
- 12 months on all our work
- Quote
- A clear price before work begins
- Telephone
- 0345 464 0079
- Page updated
- 26 October 2026
Looking after it afterwards
Good habits help new joints last longer. A few tips:
- Keep photos and emails about snagging items
- Clean sealant with mild detergent, not abrasives
- Raise failed sealant with the developer while you’re covered
- Use the extractor fan every time you shower
Keep photos of the joints and any snagging correspondence with your builder. 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. Small faults turn into leaks if left.
Landlord and commercial work in St Mary's
From a single let to a portfolio, you get the same standard of work: the old material taken out, careful preparation and a 12-month guarantee.
Housing providers, facilities teams and property managers book us too. Several sites can be quoted together.
Common questions in St Mary's
Do you cover smaller places like St Mary's?
Yes, St Mary's is covered. Our work covers London and the South East, from towns to the smallest places. The journey is planned ahead, so it helps to know about access.
I let a flat near Southampton Central station. Can you help?
Yes. We work for letting agents and landlords as well as homeowners. Just ring 0345 464 0079 or drop us an email with the address and what needs doing, and we will send you a clear quote.
Can you match the sealant colour to my new kitchen or bathroom?
White and clear are the most common, but sealant comes in other colours too. We choose one to suit the room before we begin.
Is it messy?
No. We protect the surfaces around the joints, and we tidy up before we go.
Where are you based?
We work from Crawley. Our applicators cover St Mary's.
Why does sealant fail so quickly in new builds?
It’s common, and there are usually two reasons: movement as the house dries and settles, and sealant laid onto dust without primer. A proper reseal deals with both.
Can new sealant go on top of the old bead?
No. Fresh silicone does not stick to the old layer, so it soon lifts and traps water. The old sealant always comes out first.
Do you hold any approvals?
Yes. We’re approved under the ARBOMaster scheme, the approved applicator scheme for Arbo sealants.
How the visit works
We keep the work tidy and contained to the joints we are treating, so you can get on with your day. Expect the work to take a few hours for most snagging lists, longer for a run of plots. Parking around St Mary's is normally easier than in a town centre, but mention any lanes, gates or long drives. If the job is outside, tell us about side access and how high the joints are.
- First we work through your snagging list or plot schedule with you.
- The old bead comes out in full, with no layer left behind.
- Surfaces are cleaned of building dust and primed where needed.
- A sealant chosen for each area goes in and is tooled smooth.
- We check every joint and tell you how long each needs to cure.
How to prepare
- Let us know about parking restrictions
- For indoor joints, keep the area dry beforehand if you can
- Let us know about earlier repairs to the joints
Ask for a quote
To get a quote, phone 0345 464 0079 or drop us an email with the location and a short description of the problem. You’ll have a clear quote before work begins.
Related advice
Leave it or put it right?
Small cosmetic gaps can wait for the house to settle, but water getting through cannot. Not sure whether yours can wait? You can ring 0345 464 0079 or send us an email with a few pictures and we will tell you. Around St Mary's, water from a failed joint in an older home can soak into timber and plaster, which is far harder to put right than the sealant itself.
A few things move the cost up or down: the old material and how easily it comes out, whether mould needs treating, and whether the work is at height. Your quote takes all of that into account.
Why St Mary's customers choose us
- Neat joints and a tidy finish
- White, clear, grey or another colour, product permitting
- Colour agreed with you before any work starts
- Sealant colour chosen to suit
See our cost guide and our reviews.
Different surfaces, different methods
Windows and doors
The gap between a new frame and its plaster reveal often opens up. We remove cracked sealant and apply a flexible one that suits the frame.
Plot handovers
Taking time over preparation reduces return visits. Dust from the build is removed first.
What affects the cost of new build mastic
There’s no set price list, because jobs vary so much. The quote depends on:
- The number and length of the joints
- Mould in or behind the old joints
- The product the joint needs
- Any working-time requirements on site
The cost 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.
Helping us quote
You do not need to know the technical terms. Just tell us:
- How many joints, rooms or windows are involved
- Where the job is, and your postcode
- Access, such as stairs, a lift or height
- What’s wrong with the joints now
Getting a quote is simple: let us know the job and the location. A few pictures by email make the job easier to understand, and we will come back to you with a quote.
New homes and floors in St Mary's
St Mary's is close to the coast. Plot mastic on new homes near the coast takes more weather than it would inland, so it’s worth checking at snagging. London and the South East are among the drier parts of the UK, though outdoor sealant still has to go onto a dry joint, so the forecast decides the day.
In and around St Mary's, as anywhere, good new build mastic starts with a clean, dry, properly prepared joint. For new homes near Southampton Central station, it’s worth checking the sealant early, while snags are still fresh.
St Mary's is about 1 mile south of Southampton, in Southampton. Anywhere in SO14, we cover new build mastic for homes and businesses. 40 places in Southampton are on our list.
Here we cover the SO14, SO15 and SO18 postcode area for new build mastic. New build mastic is available to properties on New Road, Ogle Road and Marsh Lane and the roads around them. Nearby, we also carry out new build mastic in Northam (1 mile north-east), Inner Avenue (1 mile north), Peartree Green (1 mile east), Southampton (1 mile north) and Bitterne Manor (1 mile north-east). Within a short drive, we also cover Chartwell Green (3 miles north-east), Harefield (3 miles east), Maybush (3 miles north-west), Coxford (3 miles north-west), Lordswood (3 miles north-west) and Eling (4 miles west).
Around St Mary's
We work in homes and buildings around The Joiners pub, Woolston School and Houndwell Park and the streets around them. For rail, the closest station is Southampton Central station, about 0.8 miles west. Nearby you’ll also find Netley Castle (2.5 miles south-east) and Bargate Guildhall Museum (under half a mile south-west). Not far away are Netley Common.