West Berkshire · England
New Build Mastic in Colthrop
Plot mastic for developers and snagging failed sealant in new homes in Colthrop, with a one-year guarantee on every job. Call for a quick quote.
- Sealant applied over dusty or wet surfaces
- Sealant work across a run of new homes
- Frame joints opening as the plaster dries
New build mastic in Colthrop, done properly
Some owners wait for the first year’s movement before having joints redone. For small cosmetic gaps, that is reasonable, but a seal that is letting water through needs doing now. We work on plot handovers, windows & doors and skirting & floors, and common reasons people get in touch are frame joints opening as the plaster dries and leaking shower tray seals in a new home.
Somewhere as small as Colthrop, new homes tend to be conversions, self-builds or a few houses rather than an estate. Every one needs its sealant and floor joints done properly, whatever the size of the site.
Big or small, you get the same 12-month guarantee in Colthrop and across West Berkshire.
- Where
- Colthrop (RG19, RG18)
- Region
- West Berkshire
- Cover
- A year, on every job
- Quote
- A clear price before any work starts
- Phone
- 0345 464 0079
- Last updated
- 26 October 2026
Why it’s worth doing now in Colthrop
DIY kits do not solve the main problems with new-build sealant: grit, unprimed surfaces and old layers underneath. Proper removal and preparation are what make it last. In a small place like Colthrop, homes can be exposed to wind and rain, which finds any gap, and damp in older walls is slow to dry out.
We do not show prices on the website, because the cost depends so much on the job itself. Call for a quick quote.
What you get with us
- We agree the colour with you first
- More than 20 years in sealant work
- Trusted Arbo and Everbuild sealants
- 180+ five-star Google reviews
Read what affects the cost or our reviews.
What happens on the day
Once we’re on site, we check the joints match what you told us. If we find something unexpected, we talk it through with you first. After that, the work takes a few hours for most snagging lists, longer for a run of plots. In a small place like Colthrop, access is generally the main thing to plan. If the job is outside, mention outbuildings, exposed walls and how to reach them.
- We start by agreeing which joints are on the list, from the snagging sheet or plot schedule.
- We cut out every bit of the failed or messy sealant.
- Surfaces are cleaned of building dust and primed where needed.
- A sealant chosen for each area goes in and is tooled smooth.
- Each area is checked and left with its cure time.
Getting ready for the visit
- Tell us about any previous sealing or DIY attempts
- Tell us if parking is tricky
- Let us know if you’ve seen damp or leaks
Getting a quote
For a quick quote, get us on the phone, or email us if that’s easier. Describe what needs sealing and we will talk you through the work and send you a clear quote.
Read more
New build mastic in Colthrop: local notes
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.
For new homes near Thatcham station, it’s worth checking the sealant early, while snags are still fresh.
Colthrop is about 1 mile east of Thatcham, in West Berkshire. We provide new build mastic to householders, landlords and businesses in Colthrop. Colthrop is one of 155 places in West Berkshire we cover for new build mastic. You can also see our page for Reading, roughly 12 miles from Colthrop.
Jobs for new build mastic in RG19 and RG18 is quoted and booked the same way as anywhere else. We cover properties on Bath Road, Ashman Road and Fokerham Road and the roads around them. Neighbouring places we cover for new build mastic include Crookham (2 miles south-east), Hyde End (2 miles south-east), Heads Hill (2 miles south-west), Mill Green (2 miles south) and Goose Hill (3 miles south). We also work in nearby towns such as Newbury (4 miles west), Burghfield Common (8 miles east), Speenhamland (4 miles west), Hungerford (12 miles west), Spencers Wood (12 miles east) and Calcot (9 miles east).
Local landmarks in Colthrop
Locally, jobs take us to homes and businesses close to The Swan pub and Kennet School and the streets around them. The closest station to Colthrop is Thatcham station, roughly 0.5 miles south-west of the centre. Other landmarks nearby include Old Chapel Textile Centre (2.6 miles south-west) and Donnington Castle (4.6 miles west). The countryside around Colthrop includes Thatcham Reed Beds.
Places near Colthrop
More services for Colthrop
When to call us in Colthrop
When the heating goes on in the first winter, the house dries fast. Gaps open along skirting, frames and worktops and cracked sealant shows up.
Common reasons people contact us are:
- Frame joints opening as the plaster dries
- Sealant work across a run of new homes
- Smeared, uneven beads picked up at snagging
- Skirting joints opening in the first winter
Around Colthrop, as everywhere, new build mastic is only as good as the preparation behind it.
Questions to ask before booking
- What the quote includes, VAT included or not
- Whether you can choose the colour
- Whether all the old sealant comes out first
- What product goes in the joint
Work for landlords, hotels and businesses
Water getting past a failed joint can damage the building, which matters even more when someone else lives there. Resealing at the right time is simple maintenance.
If you manage several properties in or around Colthrop, jobs at different addresses can go on one quote. Just tell us the addresses and what each one needs.
Aftercare tips
To keep the joints looking good and working properly:
- Record problems with dated pictures
- Avoid running a DIY bead over the old one
- Act quickly if a seal starts to leak
- Report sealant problems to your builder during the snagging period
Watch the joints as the house settles. Small gaps can appear as the house dries.
Early snagging is easier snagging. Small faults turn into leaks if left in a busy bathroom.
What affects the cost of new build mastic
The price is agreed before any work begins. It takes into account:
- The old material and how stubborn it is
- The product the joint needs
- Any mould that needs treating
- Access and height
Combining jobs into one visit normally makes better use of the time than several visits. You’ll get one clear quote for the whole job.
What to tell us for a quote
You don’t need to know the technical terms. Just tell us:
- A few photos by email, if you can
- What the problem is, such as mould, gaps, leaks or cracking
- If it’s domestic, commercial or a hotel
- How many joints, rooms or windows are involved
If you’re in Colthrop and need new build mastic, ring 0345 464 0079 or drop us an email. A short description of the job and where it is helps us quote, and you will get a clear quote before work begins.
What we cannot put right
We won’t take on work that won’t last, so here’s what sealant can’t put right:
- Leaking fittings rather than failed sealant
- Broken tiles or a split tray
- A tray or bath that is not properly supported, until it’s fixed
If you are not sure, just phone 0345 464 0079 or email us and we’ll give you a straight answer.
Surfaces we seal
- Bathrooms & en suites
- Windows & doors
- Show homes
- Plot handovers
- Kitchens
- Skirting & floors
Colthrop questions
Can you help a landlord with a rental near Thatcham station?
Yes, rental work is part of what we do. You can call 0345 464 0079 or send us an email with the address and a few details, and we will give you a fixed price before any work starts.
Can you do new build mastic in Colthrop?
Yes. We work across London and the South East, and Colthrop is part of that. You can phone 0345 464 0079 or drop us an email and tell us what needs doing, and we will give you a clear price.
How much does new build mastic cost in Colthrop?
Size, access and the old material all affect the cost. Ask us for a quote.
Where are you based?
Mr Mastic is based in Crawley. We cover Colthrop and the rest of West Berkshire, along with the rest of our area.
Is it worth trying it myself?
You can, for simple jobs. Preparation is everything: all the old sealant out, and a clean, dry joint. We can always put it right if it fails.
Do the sealants smell?
Some sealants have a smell while they cure. Opening a window helps.
Do you work for hotels and businesses?
Yes. Hotels, offices and other businesses use us.
Which products do you use?
Products from Arbo and Everbuild, among others, chosen to suit the joint. We’ll tell you what we’re using and why.