West Berkshire · England
Window & door mastic in Colthrop, West Berkshire
Our applicators work in Colthrop on mastic around window and door frames, sills and patio doors. Old sealant removed completely, joints prepared properly.
- Gaps where the sill meets the wall
- Rain getting in at the frame or under the sill
- Untidy mastic left by window fitters
How we handle window mastic in Colthrop
A window frame and the wall around it expand and shrink at different rates. Plastic and aluminium frames move with the temperature, while masonry stays fairly still. So the sealant has to stretch and recover, which is why we use a low-modulus product. We work on aluminium frames, uPVC windows and patio & French doors, and common reasons people get in touch are rain getting in at the frame or under the sill and black, perished sealant on frames.
In a village or hamlet like Colthrop, older cottages and farmhouses often have timber windows set in stone or brick. Not every older frame suits a modern silicone bead, so the sealant has to be chosen to suit the building.
The work is guaranteed for twelve months. If there’s a problem with our work within the year, let us know and we’ll sort it.
- Place
- Colthrop (RG19, RG18)
- Wider area
- West Berkshire
- Cover
- One year on every job
- Price
- A clear price before we start
- Call
- 0345 464 0079
- Last updated
- 26 October 2026
Frames and glazing around Colthrop
With historic houses such as Shaw House (about 3.5 miles west) nearby, there’s older building stock in the area around Colthrop as well as newer homes. Where a home is older, older timber frames in brick or stone need a different approach from a modern uPVC window. 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.
Homes close to St Mary's Church include some older properties, and the windows may be timber, sash or later replacements, and each needs the right sealant against the wall. For landlords with property near Thatcham station, cracked frame mastic tends to show up as a draught or damp complaint, so it’s worth checking between lets.
Colthrop is about 1 mile east of Thatcham, in West Berkshire. Wherever you are in the RG19 postcode area, our applicators can take on window mastic. We cover 155 towns and villages across West Berkshire, from the larger towns to small villages. You can also see our page for Reading, about 12 miles away.
Postcode districts we cover here for window mastic: RG19 and RG18. You will find streets such as Bath Road, Ashman Road and Fokerham Road, all of which we cover. If you are just outside Colthrop, we cover 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). Larger places within reach include 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).
Near you in Colthrop
In Colthrop, that means homes and buildings near 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). Not far away are Thatcham Reed Beds.
Why act early in Colthrop
Running fresh sealant over the old joint is tempting, but it won’t grip old, dirty sealant. It soon lifts and the leak carries on behind it. Proper resealing starts with removing the old joint. In a small place like Colthrop, homes can be exposed to wind and rain, which finds any gap, and older walls, once damp, take a long time to dry.
The cost reflects the work involved, not a rough estimate. That’s why we ask about the job first and give you a clear quote before any work starts.
Why choose Mr Mastic in Colthrop
- White, clear, grey or coloured to suit, where the product allows
- We’re fully insured
- We never seal over old sealant
- Colour picked to suit the job
See our cost guide or customer reviews.
What sealant work cannot fix
New sealant cannot fix everything, and we will tell you before any work starts. Sealant won’t put right:
- Soft or decayed wood in the frame
- Penetrating damp from a failed cavity tray or render
- Broken hinges, locks or handles
If in doubt, ring 0345 464 0079 or email us and we will say what we think before booking.
Where we work in Colthrop
- Composite doors
- Timber windows & doors
- Patio & French doors
- uPVC windows
- Window sills
- Aluminium frames
What affects the cost of window mastic
Call for a quick quote. What matters most is:
- The amount of work
- Mould in or behind the old joints
- The product the joint needs
- Whether old sealant or filler has to be cut out
Instead of a standard rate, we look at what your job involves: the amount of work, the old material and the access. The price is agreed before we begin.
What to tell us for a quote
To make quoting easier, please include:
- Where the property is
- Pictures of the joints, sent by email
- The rough size of the job
- Whether it’s a home or a business
For a quote, phone 0345 464 0079 or send us an email with the location and a short description of the problem. We will send you a clear quote before any work starts.
Towns and villages near Colthrop
What else we do in Colthrop
How the job changes by surface
Composite doors
An exposed front door gets wind-driven rain. We pay most attention there.
Aluminium frames
Aluminium needs a sealant that bonds to coated metal, and acetoxy silicones aren’t used, as they can attack some metals. We use a neutral-cure product.
Your questions about window mastic in Colthrop
Will you come out to Colthrop?
Yes, Colthrop is covered. We work across London and the South East, from towns to the smallest places. The journey is planned ahead, so it helps to know about access.
Do you work for landlords with property near Thatcham station?
Yes, rental work is part of what we do. You can ring 0345 464 0079 or drop us an email with the address and a few details, and we will give you a fixed price before any work starts.
Are you insured?
Yes, we’re fully insured for every job we do.
Do you hold any approvals?
Yes. We are an ARBOMaster approved applicator, which is run for the Arbo sealant brand.
How long before the joint can be used?
Most sealants are touch-dry well before they’re fully cured. We will tell you how long to leave the joint before we leave.
What does window mastic cost?
We don’t publish prices, because the cost depends on the job: how much there is, what’s there now, how we reach it and what it needs. You will get a clear quote before we start.
Can new sealant go over the old?
No. New silicone won’t bond to old silicone, and anything trapped underneath, including mould and water, stays there. We remove it all first.
Do I have to be there?
If the work is inside, we need someone to let us in. Once we have agreed the job, you don’t need to watch us work.
Signs you need window mastic in Colthrop
Plenty of failed mastic was poorly applied in the first place. Mastic laid onto dusty, damp or crumbling surfaces never bonded as it should, so it comes away long before its time.
Signs it’s time to call us include:
- Cold air getting in at the frame edge
- Untidy mastic left by window fitters
- Cracked or shrunken mastic around the frame
- Sealant in the wrong colour for the frame
Schools such as Francis Baily Primary School are buildings too, and its window and door frames need their mastic kept sound, just like a home’s.
Comparing quotes
- What preparation is included
- How hidden problems are handled
- Is the old sealant removed completely?
- Whether VAT is included
What we do, step by step
When we arrive, we start by going over the job with you, so there are no surprises. We protect the surfaces around the joints before work begins. Most jobs take anything from an hour or two to a full day, depending on how many frames there are. In a small place like Colthrop, access is usually the main thing to plan. For outside work, also let us know about exposed walls and any outbuildings involved.
- We check each frame and agree which ones need doing.
- Next the failed sealant is cut away and the joint cleaned.
- Where gaps are deep, backing rod goes in first.
- New exterior sealant goes on in a matching colour and is tooled smooth.
- Every joint is checked before we leave.
Getting ready for the visit
- For business premises, tell us about site rules or sign-in
- Let us know if you’ve seen damp or leaks
- Let us know about earlier repairs to the joints
Ask for a quote
Every job is quoted individually. Just call 0345 464 0079 or drop us an email with the details and send pictures if you have them.
Advice
DIY sealant or a professional job?
The biggest DIY mistake is sealing over old sealant. Silicone does not stick to old silicone, so it lifts and traps water and mould underneath. All the old material has to come out first.
Some sealant jobs are within reach of a careful DIYer, such as a straightforward joint indoors. Where it goes wrong is sealing over the old bead, working on a wet joint or overloading the gap.