West Berkshire · England
Sand Mastic in Colthrop
Problem with your window and door surrounds in Colthrop? We cut out the old, prepare the joints and apply the right sealant, and the work is guaranteed for a year.
- Old sand mastic that has cracked, crumbled or fallen out
- Open joints round the window box
- Modern sealant on a period surround
Why deal with it now?
New mastic over crumbling mastic won’t hold. We remove the loose material first so the new mastic stays put. Where a wall is exposed, as many are in small places like Colthrop, wind-driven rain gets into any failed joint, and older walls, once damp, take a long time to dry.
Every job is a little different, so each one gets its own quote. Size, access and the product the joint needs all make a difference, and we will explain the quote if you ask.
Why Colthrop clients choose us
- Quality sealants from Arbo and Everbuild
- ARBOMaster approved applicator
- Domestic, commercial and hotel work
- 20+ years of sealant experience
Take a look at what affects the cost or customer reviews.
Sand mastic for homes and businesses in Colthrop
On many period windows, sand mastic looks right and suits the building. Newer frames normally get a flexible sealant instead, and we’ll talk through which suits your home. We work on tenement windows, period & listed homes and sash and case windows, and the jobs we see most are wind and rain getting in round a sash window and gaps between timber frames and stone or brick.
Mastic can only go onto a dry, clean joint, so window work in Colthrop is booked around the forecast. Tell us about access to every side of the house, including upper-floor windows.
A one-year guarantee comes with the work, just as it does everywhere we cover.
- Location
- Colthrop (RG19, RG18)
- Wider area
- West Berkshire
- Guarantee
- 12 months on all our work
- Quote
- Quoted before any work starts
- Telephone
- 0345 464 0079
- Last updated
- 26 October 2026
What the job involves on each surface
Brick reveals
An open joint at a brick reveal lets weather in. New mastic seals the gap.
Sash and case windows
The box of a sash and case window sits in the stone or brick opening. The gap round it is pointed with sand mastic.
What happens on the day
We bring everything the job needs with us, so you do not need to buy or prepare anything. After a quick look at the joints together, we protect the area and start. Most jobs take a few hours per window, depending on the condition of the joints. Somewhere like Colthrop needs a little journey planning: let us know about lanes, gates and parking. We bring what the job needs, so it can be finished in one trip where possible.
- First we agree which joints need doing.
- Old mastic and any loose material are raked out.
- We pack any deep voids first.
- We apply the mastic by hand and shape it.
- The surface is finished to suit the stone or brick.
Preparing for the visit
- Clear the area around the work
- For indoor joints, keep the area dry beforehand if you can
- Tell us about any previous sealing or DIY attempts
Ask for a quote
The more we know about the job, the more useful the quote. Tell us where the job is, what’s wrong and how much there is.
Advice
Signs you need sand mastic in Colthrop
Age is the main cause. Sand mastic is a maintenance item like any pointing, depending on exposure and upkeep.
These are the problems we’re asked about most:
- A silicone bead on a sash window that spoils the look
- Mastic that needs renewing before redecorating
- Gaps round a timber door in stone or brick
- Crumbling sand mastic round a window
For an older house near a landmark such as St Mary's Church, replacement windows fitted into old openings often leave uneven gaps that need backing and a flexible joint.
What to look for in a quote
- Is VAT in the price?
- How the colour is chosen
- When the joint can take water or movement
- Which sealant they’ll use, and why
Your questions about sand mastic in Colthrop
Is Colthrop in your area for sand mastic?
Yes. Our work covers London and the South East, and Colthrop is part of that. You can ring 0345 464 0079 or send us an email and let us know what needs doing, and we will send you a clear quote.
Can you help a landlord with a rental near Thatcham station?
Yes, rental work is part of what we do. Just ring 0345 464 0079 or email us and tell us about the property, and we will give you a clear quote.
Can new sealant go over the old?
No, it won’t last. It can look neat for a few weeks, but the new layer lifts away from the old one. The old sealant has to come out completely.
What should I tell you?
Just the basics: the address or postcode, what’s wrong and any access issues. After that, simply ring 0345 464 0079 or send us an email.
Do you offer different sealant colours?
Yes. Sealants come in white, clear, grey and other colours for many products, and we agree the colour with you before any work starts.
Can you quote for more than one area?
Yes. Tell us about everything you’d like done.
What is sand mastic?
It’s sand mixed with a linseed-oil-based binder, used between timber frames and stone or brick.
How long does sand mastic take to go off?
Not straight away. It skins first and hardens fully later and we will give you an idea for your job.
Can I do it myself?
What a professional job adds is preparation and the right product. We take joints back to clean, dry surfaces, and the sealant is chosen for how the joint moves and where it is, then guaranteed for a year.
Not every job suits DIY: high-level joints, fire-rated gaps, external movement joints and big jobs need the right product, the right access and the right method.
Windows and doors in Colthrop
Historic houses like Shaw House (about 3.5 miles west) are a reminder that the area around Colthrop has older buildings as well as new. In older buildings, older frames set in brick or stone need a sealant that suits them, and sometimes that is traditional sand mastic. Compared with the north and west, the South East gets less rain, though outdoor sealant still has to go onto a dry joint, so the forecast decides the day.
Letting a property close to Thatcham station? Then any sash windows need sound mastic to keep draughts and rain out. If you look after a building such as Francis Baily Primary School, its window and door frames need their mastic kept sound, just like a home’s.
Colthrop is about 1 mile east of Thatcham, in West Berkshire. Colthrop gets the same service as everywhere we cover: the old material taken out, joints prepared properly and a 12-month guarantee. Colthrop is one of 155 towns and villages in West Berkshire where we work. Our Reading page covers work nearby (12 miles or so).
Every address in RG19 and RG18 is within our area for sand mastic. If you need sand mastic at a property on Bath Road, Ashman Road and Fokerham Road or a nearby road, our applicators can take on the job. We also 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). 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).
Around Colthrop
Typical jobs here are in homes near The Swan pub and Kennet School, among other places. Colthrop’s nearest station is Thatcham station, roughly 0.5 miles south-west of the centre. Nearby you’ll also find Old Chapel Textile Centre (2.6 miles south-west) and Donnington Castle (4.6 miles west). For a walk, there’s Thatcham Reed Beds.
Landlords, agents and businesses in Colthrop
We work for landlords and agents as well as householders. Resealing between tenancies keeps a property looking cared for.
Hotels need rooms back in use, so the work can be planned room by room. We’ve worked in hotels as well as homes and businesses.
Aftercare tips
To keep the joints looking good and working properly:
- Avoid heavy scraping on the mastic joint
- Renew mastic before redecorating the windows
- Ask us before painting near the mastic
- Ask a joiner to look at soft timber first
Leave the new mastic unpainted, as traditional guidance advises. Ask us before any decorating around it.
It’s best to renew mastic before painting the windows. Painting over failed mastic hides the problem for a while.