Oxfordshire · England
Sand mastic for sash & case windows in Cowley, Oxfordshire
We cover Cowley for traditional burnt sand mastic around sash and case windows and doors in stone and brick. Old sealant removed completely, joints prepared properly and every job guaranteed for a year.
- Gaps where the frame meets the masonry
- Tired mastic found when preparing windows for paint
- Old sand mastic that has cracked, crumbled or fallen out
About our sand mastic in Cowley
A silicone bead around a sash window can look out of place and isn’t always the right material. Sand mastic is the traditional choice and we can swap the silicone for it. Typical jobs include gaps where the frame meets the masonry and draughty sash windows at the surround, across timber door frames, sash and case windows and tenement windows.
Homes around Cowley range from older properties to newer houses, and their windows range just as widely. The right sealant depends on the frame and on what it sits in.
You get a one-year guarantee, the same in Cowley as everywhere else we work.
- Location
- Cowley (OX4, OX3)
- Region
- Oxfordshire
- Cover
- A year, on every job
- Price
- Quoted before any work starts
- Call
- 0345 464 0079
- Last updated
- 26 October 2026
The process
You do not need to clear the whole room or building, only the area right around the joints. Everything nearby is protected, and the job takes anything from a few hours to a full day, depending on how many windows in most cases. For a job in Cowley, we agree the time, the access and parking before the day. Outdoor jobs depend on a dry day, since sealant needs a dry surface.
- Each surround is checked first.
- We rake out the old mastic and clean the joint.
- Large voids are packed out.
- New sand mastic is applied and shaped by hand.
- We finish the mastic to a tidy line.
Getting ready for the visit
- Let us know about earlier repairs to the joints
- Move anything stored near the joints
- Tell us about any water getting in
Getting a quote
The more we know about the job, the more useful the quote. Let us know the location, the problem and roughly how many joints.
Related advice
When something else is needed
We will not take on work that will not last, so these are the limits:
- Sashes that rattle, stick or won’t open
- Cracked or broken glass
- Whether work needs listed building consent
If in doubt, ring 0345 464 0079 or email us and we’ll say what we think before you book.
Where we work in Cowley
- Brick reveals
- Stone surrounds
- Period & listed homes
- Timber door frames
- Sash and case windows
- Tenement windows
For landlords 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 that we can handle for you.
Letting agents often deal with us directly. Tell us the address, the job and how access works and we will quote.
Signs you need sand mastic in Cowley
Age is the main cause. Sand mastic is a maintenance item like any pointing, depending on exposure and upkeep.
Signs it’s time to call us include:
- Window mastic to renew ahead of painting
- Gaps where the frame meets the masonry
- Old cement repairs round a window that have failed
- Crumbling sand mastic round a window
If you live in an older home near Church of St Luke, the windows may be timber, sash or later replacements, and each needs the right sealant against the wall.
Questions to ask before booking
- Whether the sealant suits the joint
- How much experience the applicator has
- What preparation is included
- How the colour is chosen
Different surfaces, different methods
Timber door frames
Doors face weather and wear and the mastic can crack early. It’s renewed by hand.
Tenement and terrace windows
Tenements and terraces often have many sash windows with ageing mastic. We can do one window or several.
FAQs for Cowley
I let a flat near Oxford station. Can you help?
Yes, rental work is part of what we do. Just call 0345 464 0079 or drop us an email and tell us about the property, and we will give you a clear quote.
Do you cover Cowley for sand mastic?
Yes, Cowley is within the area we cover. We work across London and the South East. You can ring 0345 464 0079 or email us and let us know what needs doing, and we will send you a clear quote.
What guarantee comes with the work?
All our work has a one-year guarantee, and we are fully insured.
What does sand mastic cost?
Size, access and the old material all affect the cost. Call for a quick quote.
Should I use sand mastic or silicone?
We will talk it through with you. Period homes often look best with sand mastic, and modern sealants suit newer frames.
Should I try DIY first?
Sometimes. The key is preparation: remove all the old material and work on a clean, dry joint. If it does not work out, we can redo it.
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 you quote for more than one area?
Yes. More than one area can be quoted together.
What sand mastic looks like in Cowley
With historic houses such as Holywell Manor (about 2.1 miles north-west) nearby, there’s older building stock in the area around Cowley as well as newer homes. In older buildings, older frames set in brick or stone need a sealant that suits them, and sometimes that is traditional sand mastic. Rainfall in the South East is lower than in much of the UK, though outdoor sealant still has to go onto a dry joint, so the forecast decides the day.
Schools such as Our Lady's Roman Catholic Primary School are buildings too, and its window and door frames need their mastic kept sound, just like a home’s. For landlords with property near Oxford station, older sash windows in a rental need their mastic kept sound to keep the weather out.
Cowley is about 1 mile south-east of Oxford, in Oxfordshire. Anywhere in OX4, we can carry out sand mastic at your property. Our Oxfordshire coverage runs to 443 places, Cowley among them.
We work across the OX4 and OX3 postcode area for sand mastic. Whether your property is on Barns Road, Marsh Road and Clive Road or anywhere close by, we can help. We also cover Iffley (1 mile west), Blackbird Leys (1 mile south), Donnington (1 mile north-west), Littlemore (1 mile south-west) and Oxford (1 mile north-west). Further out, we also cover Didcot (9 miles south), Bicester (12 miles north), Abingdon-on-Thames (5 miles south-west), Witney (12 miles west), Thame (10 miles east) and Wantage (13 miles south-west).
Around Cowley
Locally, jobs take us to homes and businesses close to The Nelson pub, South Park and Emmanuel Christian School and the streets around them. Other local landmarks include Greyfriars Catholic School (0.6 miles north-west) and Alexander Library of Ornithology (1.9 miles north-west). The closest station to Cowley is Oxford station, about 2.7 miles north-west of the centre. A little further out are Templars Square (within half a mile south-west) and British Tattoo History Museum (0.7 miles north-west). Green spaces nearby include Headington Hill and CS Lewis Nature Reserve.
Why deal with it now?
Cement-based fillers and modern sealants don’t always suit a period surround. Sand mastic matches what was there, which can matter on listed and conservation-area homes. Homes in smaller places like Cowley can face more weather, and failed outside joints let damp into walls. Indoors, a failed seal lets water into floors and panels as it would anywhere.
Instead of a standard rate, we price the job in front of us: the amount of work, the old material and the access. The price is agreed before we begin.
What you get with us
- Any old sealant cut out fully, not covered over
- Rated 4.9 stars on Google
- Sanitary silicone with an anti-fungal additive in wet areas
- We’re fully insured
See what affects the cost and customer reviews.
What affects the quote in Cowley
Some jobs are bigger than they look, and some smaller. The main factors:
- How easy the joints are to reach
- How many rooms, windows or areas are involved
- Whether there’s mould to deal with
- The product the joint needs
What it costs depends on the amount of work, how hard the old material is to remove and how easy the joints are to reach. We give a clear quote before any work starts, so you know where you stand.
What we need to know
What to tell us when you ask for a quote:
- What the problem is, such as mould, gaps, leaks or cracking
- The address or postcode of the job
- Whether it has been sealed before
- A few photos by email, if you can
Every job is quoted individually, so the first step is telling us about yours. Just phone 0345 464 0079 or drop us an email with the details.