Hampshire · England
New-build mastic & snagging in Newnham, Hampshire
Professional new build mastic in and around Newnham, with old sealant always removed completely and a 12-month guarantee.
- Sealant work across a run of new homes
- Sealant applied over dusty or wet surfaces
- Cracked sealant around new window and door frames
What we’re called out for in Newnham
The first winter with the heating on dries a new home quickly. Gaps open along skirting, frames and worktops and cracked sealant shows up.
The problems people usually mention when they call are:
- Shower seals failing in the first year or two
- Plot mastic for developers ahead of handover
- Gaps between new skirting and floors
- Internal frame sealant that has split
Around Newnham, as everywhere, new build mastic is only as good as the preparation behind it.
Before booking anyone
- What happens if the job turns out different
- What preparation is included
- When the joint can take water or movement
- How the colour is chosen
How we handle new build mastic in Newnham
Across Newnham, we work for both new-home owners and the builders handing those homes over. One shower or a whole phase of plots, the method does not change: remove, clean, prime where needed, then a neat new bead. We are often asked to deal with cracked caulk along new skirting and cracks appearing as a new home settles, on show homes, bathrooms & en suites and windows & doors.
In a village or hamlet like Newnham, new homes are more likely to be a barn conversion or a handful of houses than a big estate. Each still needs its sealant and floor joints finished properly.
Whatever the size of the job, it’s backed by our one-year guarantee.
- Place
- Newnham (RG27)
- Wider area
- Hampshire
- Guarantee
- A year, on every job
- Quotes
- Quoted before any work starts
- Phone
- 0345 464 0079
- Updated
- 26 October 2026
Should I try it myself first?
If you do try it yourself, take your time over the preparation: take out all the old sealant, make sure the joint is clean and dry, and give it the full cure time. If it fails, we can still redo it.
A careful DIYer can reseal a simple joint, like a short, easy-to-reach joint indoors. The common mistakes are sealing over old sealant, sealing a damp joint and using far too much.
What we can’t put right
Sealant isn’t the answer to every problem, and we’d rather say so up front. It will not solve:
- Settlement cracks that need a surveyor
- Disputes or warranty claims with your builder
- Leaking fittings rather than failed sealant
If in doubt, ring 0345 464 0079 or email us and we will say what we think before you book.
Surfaces we seal
- Skirting & floors
- Show homes
- Plot handovers
- Kitchens
- Bathrooms & en suites
- Windows & doors
Joints and finishes in Newnham homes
London and the South East are among the drier parts of the UK, but outside sealant still needs a dry, clean surface, so outdoor work is planned around the forecast.
For new homes near Hook station, it’s worth checking the sealant early, while snags are still fresh.
Newnham is about 5 miles east of Basingstoke, in Hampshire. We provide new build mastic to homes and businesses in Newnham and nearby. 683 places in Hampshire are on our list, from the larger towns to small villages. You can also see our page for Reading, roughly 12 miles from Newnham.
We cover every part of the RG27 postcode area for new build mastic. We cover properties on Tylney Lane, Newnham Lane and Ridge Lane. We also cover Nately Scures (1 mile south), Hook Common (1 mile south-east), Up Nately (1 mile south), Hook (1 mile east) and Warnborough Green (2 miles south-east). We also work in nearby towns such as Basingstoke (5 miles west), Farnborough (10 miles east), Fleet (7 miles east), Aldershot (10 miles east), Alton (9 miles south) and Yateley (8 miles north-east).
Local landmarks in Newnham
The nearest railway station is Hook station, about 1.2 miles east. Nearby you’ll also find Odiham Castle (1.9 miles south-east) and Basing House (2.8 miles west). Open spaces near Newnham include Dogmersfield Lake and Tundry Hill.
The process
All our tools and materials come with us in the van, so there’s nothing for you to buy. Once we’ve agreed what’s being done, the area is protected and the work begins. It normally takes a few hours for most snagging lists, longer for a run of plots. In a small place like Newnham, access is generally the main thing to plan. For outside work, also let us know about exposed walls and any outbuildings involved.
- We start by going through the snagging items or plot schedule with you.
- Every bit of the old builder’s sealant is cut out, with no layer left behind.
- We clean out the dust and grit left from the build.
- Primer goes on where the surface and product need it, then the new sealant.
- Each bead is tooled and the cure times explained.
Before we arrive
- Tell us about access, such as stairs, a lift or high-level joints
- Let us know if you’ve seen damp or leaks
- Where the joints are inside, avoid wetting them before we arrive
Get a quote
We quote each job on its own, so the first step is telling us about yours. Just phone 0345 464 0079 or drop us an email with the details and send pictures if you have them.
Advice
Surface by surface
Bathrooms and en suites
Shower trays in new homes often move slightly in the first year. The joint is stripped back before the new bead goes in and baths are filled before sealing.
Skirting and floors
As timber and screed dry, skirting and floors shift. Caulk cracks; a flexible sealant moves with it.
Keeping the joints in good condition
Once the sealant has cured, a few habits help it last:
- Use the extractor fan every time you shower
- Photograph failed sealant before it’s redone
- Raise failed sealant with the developer while you are covered
- Watch for new gaps as the house dries out
Don’t stand on the bath edge or the lip of the tray while the sealant cures. Report any movement in a bath or tray.
If a shower tray or bath seal splits in the first year, look for movement. Have it resealed, and the tray or bath checked, before it gets worse.
Towns and villages near Newnham
More services for Newnham
Your questions about new build mastic in Newnham
Can you do new build mastic in Newnham?
Yes. Our work covers London and the South East, and Newnham is part of that. Just call 0345 464 0079 or send us an email with a few details of the job.
Do you cover smaller places like Newnham?
Yes, smaller places are covered as well as towns. We work across London and the South East. Let us know about access, parking and anything unusual about getting there when you book.
Are you an approved applicator?
Yes. We’re ARBOMaster approved, the scheme for applicators of Arbo sealants.
How long does the job take?
Typically it takes a few hours for most snagging lists, longer for a run of plots. Bigger jobs take longer.
Do you guarantee your work?
Yes. All our work carries our one-year guarantee.
Are you fully insured?
Yes. Mr Mastic is fully insured.
Can you reseal over the builder’s sealant?
No. Fresh silicone doesn’t stick to the old layer, so it soon lifts and traps water. The old sealant always comes out first.
Why has my new-build shower seal failed already?
A new house dries and settles for a year or two, and sealant is often rushed onto dusty, unprimed surfaces. Either can make it fail early.
Why it’s worth doing now in Newnham
A hairline gap at a skirting can wait, but water getting through can’t. Not sure whether yours can wait? You can phone 0345 464 0079 or email us with a few photos. Where a wall is exposed, as many are in small places like Newnham, wind-driven rain gets into any failed joint, and damp in older walls is slow to dry out.
No two jobs are quite the same, so each one gets its own quote. The number of joints, how easy they are to reach and the sealant needed all make a difference.
Why book with us
- Neat joints and a tidy finish
- You choose the colour before work begins
- Experience in homes, commercial sites and hotels
- White, clear, grey or another colour, product permitting