Oxfordshire · England
External Mastic in Lewknor
Professional external mastic in and around Lewknor, with old sealant always removed completely and a 12-month guarantee.
- Failed seals between different materials
- Old sealant gone brittle and cracked
- Rigid filler in a joint that should flex
External mastic in Lewknor, done properly
Failed sealant is cut out, the depth set with closed-cell backing rod, and the joint resealed with a low-modulus sealant made for outside. The colour is chosen to suit the brick or render so the line blends in. Typical jobs include gaps where render, brick and frames meet and hard, crazed mastic that has stopped moving, across copings & trims, brickwork movement joints and concrete & block.
In a village or hamlet like Lewknor, older cottages and farm buildings often stand in the open, so walls and rooflines take the full force of wind and rain. Gutter joints and wall joints there need a sealant that can flex and stay put.
We stand behind the work with a one-year guarantee.
- Location
- Lewknor (OX49)
- Wider area
- Oxfordshire
- Cover
- One year on every job
- Quote
- Quoted before any work starts
- Phone
- 0345 464 0079
- Last updated
- 26 October 2026
Surface by surface
Copings and trims
Coping and trim joints face rain and sun head on. Each is resealed with a weatherproof, flexible sealant.
Concrete and blockwork
Big joints in concrete need careful depth control. Backing rod sized to the joint sets it and keep the sealant to the right depth.
Do you need external mastic in Lewknor?
UV, rain and frost all age exterior sealant. In time it goes hard, crazes on the surface and stops stretching, so the next time the wall moves, it splits or pulls away.
Any of these means the joints need attention:
- Hard, crazed mastic that has stopped moving
- Weeds or debris growing in open joints
- Rigid filler in a joint that should flex
- Panel joints letting water in
If you look after a building such as Lewknor Church of England Primary School, its movement joints, gutters and trims need looking after like any other building’s.
Before you book anyone
- How long the guarantee is
- How the joint is cleaned and prepared
- Is VAT in the price?
- Whether the sealant suits the joint
When it isn’t the sealant
To be straight with you, some problems need a different trade:
- Cracks in the bricks or render themselves, away from the joints
- Cutting new joints into brickwork, which is building work rather than sealant work
- Subsidence or other structural problems
Not sure which it is? You can ring 0345 464 0079 or email us and we’ll tell you honestly before booking.
Where we work in Lewknor
- Render & cladding joints
- Brickwork movement joints
- Façade panels
- Concrete & block
- Joints between brick and frames
- Copings & trims
What happens on the day
There’s no need to move everything out before we come, just the space around the work. Everything nearby is protected, and the job takes a few hours to a few days, depending on the length of joint and the access for a typical job. For a village or hamlet like Lewknor, the journey is planned in advance: let us know about lanes, gates and parking. Everything for the job comes with us, so a second trip is avoided where possible.
- We look at every joint and agree a colour to suit the wall.
- We take out the old sealant until the faces are sound.
- Backing rod goes in so the sealant can stretch between the two faces.
- Primer is applied wherever the sealant needs it.
- We gun in low-modulus sealant and tool it neatly.
Before we arrive
- Mention any parking rules near the property
- Keep children and pets away from the work area
- Mention any tricky access
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
Why act early in Lewknor
An open joint keeps letting water into the wall with every downpour. In cold weather, frost can damage wet brick and render around the joint, so the problem grows beyond the joint itself. In a small place like Lewknor, homes can be exposed to wind and rain, which finds any gap, and damp in older walls is slow to dry out.
Doing several joints on one visit generally makes better use of the time than several visits, so tell us about everything that needs sealing. We’ll send you a clear quote for the lot.
Why us?
- Tidy, careful work
- Anti-fungal silicone where joints get wet
- We never seal over old sealant
- We agree the colour with you first
Take a look at what affects the cost and customer reviews.
FAQs for Lewknor
What guarantee comes with external mastic in Lewknor?
Every job comes with our 12-month guarantee, wherever it is. We’re fully insured, and an ARBOMaster approved applicator.
Do you cover Lewknor for external mastic?
Yes, Lewknor 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.
Can you work on commercial sites?
Yes. Commercial and hotel work is a large part of what we do, as well as homes. We can talk about working times when we quote.
How do you reach high-level joints?
That depends on how high the joints are and the ground below. Ground-floor joints are simple; for higher work, tell us about the building and we’ll confirm what’s needed.
What is a movement joint?
A movement joint is a planned break in the wall that absorbs expansion and shrinkage. It’s sealed with a flexible sealant, not mortar.
Are you fully insured?
Yes. We’re fully insured.
Can new sealant go over the old?
No. Fresh sealant does not stick to old sealant, and it traps any mould or water underneath. We remove it all first.
Will the new joint stand out?
We choose a sealant colour to suit the brick, stone or render. Exterior sealants come in a good range of colours.
External mastic in Lewknor: local notes
Historic houses like Adwell House (about 1.6 miles north-west) are a reminder that the area around Lewknor has older buildings as well as new. In older buildings, older brick and stone need a sealant that suits them, at the right joint depth. 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.
In the older streets around Church of St Margaret, old and new materials meet at the roofline and walls, which is where sealant earns its keep.
Lewknor is about 5 miles south of Thame, in Oxfordshire. Homes, rented property, offices and hotels in Lewknor is covered for external mastic. Every job comes with our one-year guarantee. Our Oxfordshire coverage runs to 443 places, Lewknor among them. For nearby work, see our Oxford page, about 12 miles away.
Every address in OX49 is within our area for external mastic, from the main roads to the quietest streets. Local streets include High Street, Weston Road and Lewknor Close, and we cover them all. Neighbouring places we cover for external mastic include South Weston (1 mile north-west), Aston Rowant (1 mile north-east), Postcombe (1 mile north), Shirburn (1 mile south-west) and Kingston Blount (2 miles north-east). Larger places within reach include Oxford (12 miles north-west), Didcot (13 miles west), Abingdon-on-Thames (13 miles west), Thame (5 miles north), Henley-on-Thames (10 miles south) and Benson (7 miles south-west).
Landmarks near Lewknor
We work in homes and buildings around Ye Olde Leathern Bottle Public House and Icknield Community College. Other landmarks nearby include Thame Community Hospital (5 miles north). For a walk, there’s Aston Rowant NNR and Bald Hill.
What affects the cost of external mastic
Some jobs are bigger than they look, and some smaller. What affects the quote:
- How much old sealant there is and how hard it is to remove
- Which sealant suits the joint
- Whether the work is at height
- Mould in or behind the old joints
We don’t show prices on the website, because each job is priced on what it involves. Call for a quick quote.
Asking for a quote
To help us quote quickly, let us know:
- If it’s domestic, commercial or a hotel
- Photos by email, if that’s easy
- What the problem is, such as mould, gaps, leaks or cracking
- Roughly how big the job is
If you are in Lewknor and need external mastic, phone 0345 464 0079 or send 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.
Landlord and commercial work in Lewknor
Letting agents and landlords in Lewknor can book us as well as householders. Sealant work between tenants keeps a property looking cared for.
Hotels need rooms back in use, so we plan the work room by room around your bookings where we can. We have worked in hotels as well as homes and businesses.