Oxfordshire · England
Harcourt Hill External Mastic
We cover Harcourt Hill for sealing brickwork movement joints, render, cladding and façade joints. Old material cut out, joints cleaned and sealed neatly and a one-year guarantee.
- Brick movement joints where the sealant has split
- Failed sealant between panels on a façade
- Moss and dirt in joints with no sealant left
How the job changes by surface
Joints between dissimilar materials
Joints where frames, sills or panels meet the wall are common leak points. The old joint is removed and a sealant that bonds to both sides goes in.
Cladding and façade panels
Where a cladding system has its own specified sealant, we follow it. Tell us what the building has when you get in touch.
How we handle external mastic in Harcourt Hill
As ARBOMaster approved applicators, we choose exterior sealants to suit the joint and the surfaces. Porous or awkward surfaces are primed where the sealant needs it. We work on joints between brick and frames, copings & trims and façade panels, and common reasons people get in touch are moss and dirt in joints with no sealant left and failed sealant between panels on a façade.
Around Harcourt Hill, older buildings can be stone, brick or timber-framed, many with extensions added later. The joints where those materials meet are the weak points.
You get a one-year guarantee, the same in Harcourt Hill as everywhere else we work.
- Where
- Harcourt Hill (OX2, OX1)
- Region
- Oxfordshire
- Guarantee
- A year, on every job
- Quote
- Quoted before any work starts
- Telephone
- 0345 464 0079
- Updated
- 26 October 2026
Looking after it afterwards
Good habits help new joints last longer. Our tips:
- Wash walls gently around the sealant
- Keep water from gutters off the wall
- Make sure movement joints aren’t pointed over
- Walk round the building once a year and look at the joints
Only paint over the joint if we have confirmed the sealant can take paint. Paint can crack on a flexible joint and spoil the finish.
A joint that has stopped moving pushes the movement elsewhere, generally as cracking in the brickwork or render nearby. Resealing it early helps prevent that.
Why deal with it now?
Low-modulus sealants stretch easily, so they put less strain on the joint edges. That protects surfaces like brick, render and concrete. A stiffer product can damage the joint edge as it fails. In a small place like Harcourt Hill, homes can be exposed to wind and rain, which finds any gap, and older walls, once damp, take a long time to dry.
No two jobs are quite the same, so we quote each one individually. The number of joints, how easy they are to reach and the sealant needed all play a part, and we will explain the quote if you ask.
Why Harcourt Hill customers choose us
- Homes, businesses and hotels
- Old sealant always removed completely
- 4.9 on Google from 180+ five-star reviews
- A sealant colour to suit the surroundings
Take a look at what affects the cost and our reviews.
DIY versus a professional finish
Not every job suits DIY: high-level joints, fire-rated gaps, external movement joints and big jobs call for the right materials, safe access and experience.
If you’re 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 fails, we can still redo it.
Nearby places to Harcourt Hill
What else we do in Harcourt Hill
Outside joints around Harcourt Hill
The South East is one of the drier parts of the UK, yet outdoor joints still have to be sealed dry, so jobs are booked with the weather in mind. Historic houses like Holywell Manor (about 2.3 miles north-east) are a reminder that the area around Harcourt Hill 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.
Schools such as Matthew Arnold School are buildings too, and movement joints, cladding joints and gutters on larger buildings need the same care as a house’s. If you live in an older home near Church of St Lawrence, the joints between older walls, newer extensions and the roofline need a sealant that can move.
Harcourt Hill is about 3 miles west of Oxford, in Oxfordshire. Jobs in Harcourt Hill get the same care as everywhere else we work: the old material taken out, joints prepared properly and a 12-month guarantee. Our area takes in 443 places across Oxfordshire.
We cover every part of the OX2 and OX1 postcode area for external mastic and the streets around it. Local streets include Lime Road, Cedar Road and Stanton Road, and we cover them all. Neighbouring places we cover for external mastic include North Hinksey (1 mile north), Chilswell (1 mile south), Osney (1 mile north-east), Grandpont (1 mile east) and South Hinksey (1 mile east). Larger places within reach include Oxford (3 miles east), Didcot (9 miles south), Bicester (13 miles north-east), Abingdon-on-Thames (4 miles south), Witney (9 miles west) and Carterton (13 miles west).
Around Harcourt Hill
We work in homes and buildings around Raleigh Park, Angus Library and Archive and Oxford and Cherwell Valley College, among other places. Other local landmarks include The Fishes pub (0.6 miles north-east) and North Hinksey Church of England Primary School (0.6 miles north-east). The nearest railway station is Oxford station, roughly 1.4 miles north-east. A little further out are The Story Museum (1.7 miles north-east) and Oxford Castle and earlier settlement remains (1.6 miles north-east). For a walk, there’s Cumnor Hill and Lashford Lane Fen.
What we’re called out for in Harcourt Hill
Using the wrong sealant is another common reason. A stiff, general-purpose sealant can’t cope with a joint that moves a lot, and it tears off the sides.
These are the problems we’re asked about most:
- Weeds or debris growing in open joints
- Joints with sealant missing in places
- Leaking joints around cladding and façade panels
- Water getting into walls through failed joints
Rented homes near Oxford station change hands often, and outside joints that have cracked can let damp into a rental, so check them between lets.
What your quote should include
- How long the guarantee is
- Who does the work, and how experienced they are
- What product goes in the joint
- Whether they seal over old material or remove it
Common questions in Harcourt Hill
Is Harcourt Hill within the area you cover?
Yes. Harcourt Hill is within the area we cover, which takes in towns, villages and rural addresses. Our work covers London and the South East. Just mention lanes, gates or anything else about the route when you book.
Do you work for landlords with property near Oxford station?
Yes, rental work is part of what we do. You can phone 0345 464 0079 or send us an email with the address and a few details, and we will give you a fixed price before any work starts.
What is a movement joint?
Brickwork, render and cladding all move a little, and planned joints take up that movement. It’s closed with backing rod and a flexible sealant.
Do you work for hotels and businesses?
Yes. We’ve worked for hotels, offices and other businesses, and we’re fully insured.
Is it OK to seal over old sealant?
No, and we never do. It may look fine at first, but the new bead soon lifts. The old sealant has to come out completely.
Why do you put foam in the joint first?
The foam is closed-cell backing rod. It keeps the sealant at the right depth and bonded to the sides only so it can flex with the joint.
How long does the job take?
Typically it takes anything from a few hours to several days, depending on the building. Bigger jobs take longer, and we will say how long yours will take.
Which products do you use?
We choose the sealant for the joint, not the other way round. Movement, water and weather all affect the choice.
What happens on the day
On the day, there’s very little for you to do. Show us the job and we will take it from there. The work itself takes a few hours to a few days, depending on the length of joint and the access. Somewhere like Harcourt Hill 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.
- Each joint is checked and the colour of the new sealant agreed.
- Failed sealant is removed back to clean, sound faces.
- Closed-cell backing rod is pushed in so the sealant bonds to two sides only.
- Primer is applied wherever the sealant needs it.
- A low-modulus exterior sealant is gunned in and tooled to a neat finish.
How to prepare
- Mention if the joints have been sealed before
- Clear the area around the work
- Tell us if parking is tricky
Getting a quote
Getting a quote is simple: let us know what needs doing and where and its rough size. A few photos by email make the job easier to understand, and we’ll come back to you with a quote.
Read more
What we cannot put right
Some problems need a builder, plumber or other trade rather than us:
- Cracks in the bricks or render themselves, away from the joints
- Structural movement, which needs a surveyor or engineer
- Rising or penetrating damp from elsewhere in the wall
If you are not sure, just call 0345 464 0079 or send us an email and we will give you a straight answer before booking.
What we seal
- Copings & trims
- Brickwork movement joints
- Façade panels
- Concrete & block
- Joints between brick and frames
- Render & cladding joints