Oxfordshire · England
Northmoor Sand Mastic
Specialist sand mastic for Northmoor: careful preparation, the right product and tidy work. Call for a quick quote.
- Mastic round period door frames that has failed
- Silicone on a period window that looks wrong
- Old sand mastic that has cracked, crumbled or fallen out
About our sand mastic in Northmoor
Old sand mastic cracks, crumbles and falls out over time, leaving gaps round the window. Renewing it closes the gap and tidies the surround. If you have tired mastic found when preparing windows for paint and gaps between timber frames and stone or brick, we can help, whatever the surface.
Around Northmoor, many homes face open ground, so their windows and doors take the full weather. Exposed frames and sills lose their mastic sooner than sheltered ones.
Whatever the size of the job, you get the same one-year guarantee.
- Location
- Northmoor (OX29)
- Region
- Oxfordshire
- Cover
- A year, on every job
- Price
- Quoted before any work starts
- Telephone
- 0345 464 0079
- Last updated
- 26 October 2026
How the visit works
Once we are on site, we check the joints match what you told us. If anything is different, we explain it before carrying on. After that, the work takes anything from a few hours to a full day, depending on how many windows. In a small place like Northmoor, access is normally the main thing to plan. If the job is outside, mention outbuildings, exposed walls and how to reach them.
- We look at the surrounds with you and agree the joints to renew.
- Old mastic and any loose material are raked out.
- We pack any deep voids first.
- The sand mastic is mixed and pressed into the joint by hand.
- We dress the finish so it sits neatly against the masonry.
Before we arrive
- Let us know about parking restrictions
- Mention any tricky access
- Try not to wet indoor joints just before the visit
Ask for a quote
We quote each job on its own, so start by telling us what you need. Just ring 0345 464 0079 or drop us an email with the details.
Read more
Different surfaces, different methods
Sash and case windows
The mastic round a sash window is on show, so a neat, even finish matters.
Tenement and terrace windows
Upper-floor windows need access planning. Tell us the height and we will confirm what’s needed.
Northmoor homes and the weather
Rainfall in the South East is lower than in much of the UK, but outside sealant still needs a dry, clean surface, so outdoor work is planned around the forecast. With historic houses such as Appleton Manor (about 1.7 miles south-east) nearby, there’s older building stock in the area around Northmoor as well as newer homes. In older buildings, older timber frames in brick or stone need a different approach from a modern uPVC window.
In the older streets around Church of St Denys, the windows may be timber, sash or later replacements, and each needs the right sealant against the wall.
Northmoor is about 6 miles north-west of Abingdon-on-Thames, in Oxfordshire. From the centre of Northmoor to the outskirts, sand mastic is available for homes and businesses alike, from flats and houses to offices and hotels. Our area takes in 443 places across Oxfordshire, large and small. There’s also a page for Oxford, about 7 miles away.
All of OX29 is covered for sand mastic. We cover properties on Chapel Lane and Bints Place. Close by, we work in Appleton (2 miles south-east), Sutton (2 miles north), Cumnor (3 miles east), Filchampstead (3 miles north-east) and Farmoor (3 miles north-east). Further out, we also cover Oxford (7 miles east), Didcot (10 miles south-east), Abingdon-on-Thames (6 miles south-east), Witney (6 miles north-west), Carterton (9 miles west) and Wantage (9 miles south).
Around Northmoor
In Northmoor, that means homes and buildings near The Red Lion Public House. A little further out are Abingdon Community Hospital (5.4 miles south-east) and Hinton Waldrist Castle (3.7 miles south-west). Green spaces nearby include Hitchcopse Pit and Cumnor Hill.
Why act early in Northmoor
An open joint round the frame lets weather in. Left, water can reach the timber and the wall, so dealing with it now protects both. In a small place like Northmoor, homes can be exposed to wind and rain, which finds any gap, and damp in older walls is slow to dry out.
Combining jobs into one visit is usually more efficient than separate visits. You’ll get one clear quote for the whole job.
Why us?
- Old sealant always removed completely
- Every job guaranteed for a year
- ARBOMaster approved applicator
- 4.9 on Google from 180+ five-star reviews
Read what affects the cost and what customers say.
Questions from Northmoor
Is sand mastic in Northmoor guaranteed?
All our work, in Northmoor and everywhere else, comes with a 12-month guarantee. We are fully insured, and an ARBOMaster approved applicator.
Is Northmoor within the area you cover?
Yes, Northmoor 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.
Will you leave a mess?
Very little: the area around the joints is protected first, and we tidy up before we go.
What is sand mastic?
Sand plus a binder based on linseed oil. It’s built up in the joint by hand and shaped to suit the surround.
Which is right for my windows, sand mastic or modern sealant?
It depends on the window. On many period windows, sand mastic looks right and suits the building and newer frames generally get a flexible sealant.
Should I check with the council before work on a listed or conservation-area home?
It’s best to ask your local planning authority first. Like-for-like sand mastic is often the preferred finish, but they decide.
Will there be a smell?
That depends on the sealant. Some products have a noticeable smell, others very little, and any smell fades as they cure.
How long does sand mastic take to go off?
It skins over fairly quickly but takes longer to harden fully. We will tell you what to expect for your job.
Landlords, agents and businesses in Northmoor
If you manage several properties in or around Northmoor, several properties can be quoted together. Send us the addresses and the work at each, and photos by email help.
We also work for businesses, from offices to washrooms and kitchens. For commercial premises, we can talk through working times when we quote.
Nearby places to Northmoor
More services for Northmoor
What affects the quote in Northmoor
We quote each job individually. These are the things that affect it:
- Any working-time requirements on site
- The number of rooms or windows
- Access and height
- The type of sealant required
Instead of a standard rate, we price the job in front of us: how many joints, what’s in them now and how we reach them. The price is agreed before we begin.
Asking for a quote
When you call or email, these details help:
- The address or postcode of the job
- A few photos by email, if you can
- The problem you’ve noticed
- If it’s domestic, commercial or a hotel
Need a quote? Please ring 0345 464 0079 or send us an email and tell us about the job. We’ll explain what we’d do and give you a clear price before any work starts.
Signs you need sand mastic in Northmoor
Shallow joints are a common cause. A thin layer doesn’t hold well so we make sure the new mastic is the right thickness.
Look out for these signs:
- Draughts and rain around sash boxes
- Old cement repairs round a window that have failed
- Modern sealant on a period surround
- Gaps round a timber door in stone or brick
In and around Northmoor, as anywhere, good sand mastic starts with a clean, dry, properly prepared joint.
Questions to ask before booking
- How much experience the applicator has
- How the joint is cleaned and prepared
- What happens if the job turns out different
- What the quote includes, VAT included or not
DIY sealant or a professional job?
If you are set on DIY, put the effort into preparation: take out all the old sealant, make sure the joint is clean and dry, and give it the full cure time. If it does not work out, we can still put it right.
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.