Milton Keynes · England
Great Horwood External Mastic
External mastic for Great Horwood, by sealant specialists with 20+ years’ experience. Rated 4.9 on Google from 180+ five-star reviews.
- Joints with sealant missing in places
- Damp patches traced to an open external joint
- Joints where the bead has come unstuck
How it works
When we get to you, we check the joints match what you told us. If anything is different, we explain it before carrying on. Most jobs then take a few hours to a few days, depending on the length of joint and the access. For a village or hamlet like Great Horwood, 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.
- Failed sealant is removed back to clean, sound faces.
- Closed-cell backing rod is pushed in so the sealant bonds to two sides only.
- We prime the faces where required.
- A low-modulus exterior sealant is gunned in and tooled to a neat finish.
How to prepare
- Mention any sign-in or site rules at work premises
- Mention any tricky access
- Let us know about parking restrictions
Ask for a quote
There’s no standard price list, because every job is different. Instead, your job gets its own clear quote. To arrange one, call 0345 464 0079 or email us.
Advice
External mastic for homes and businesses in Great Horwood
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, and we do not skip that step. If you’re dealing with water getting into walls through failed joints and joints pointed up with cement by mistake, we can help, whatever the surface.
Outside joints can only be sealed when they’re dry, so work in Great Horwood is booked around the forecast. Tell us about access to all sides of the building, including outbuildings and garages.
Our work is backed for twelve months.
- Place
- Great Horwood (MK17)
- Wider area
- Milton Keynes
- Cover
- A year, on every job
- Quote
- Quoted before any work starts
- Call
- 0345 464 0079
- Updated
- 26 October 2026
Different surfaces, different methods
Concrete and blockwork
Blockwork and concrete shrink over time and move with the seasons. Their movement joints are sealed over backing rod with a flexible sealant.
Copings and trims
Coping joints that leak let water straight down into the wall. Sealing them early saves the wall below.
Questions from Great Horwood
What guarantee comes with external mastic in Great Horwood?
Every job comes with our 12-month guarantee, wherever it is. We’re also fully insured and ARBOMaster approved.
Do you cover Great Horwood for external mastic?
Yes, Great Horwood is within the area we cover. Our work covers London and the South East. You can phone 0345 464 0079 or drop us an email and let us know what needs doing, and we’ll send you a clear quote.
Will there be a smell?
Possibly a little. It fades as the sealant cures.
Are you fully insured?
Yes. We’re fully insured, and we can confirm the details when we quote.
Does someone need to be in?
Access is agreed with you when the job is booked. Indoors, that normally means someone at home.
Why is there a gap in my brick wall?
A movement joint is a planned break in the wall that absorbs expansion and shrinkage. It should be filled with flexible sealant, never mortar.
Do you work for hotels and businesses?
Yes. We can plan bigger jobs in stages.
Should I try DIY first?
For a simple, easy-to-reach joint, a careful DIYer can do a reasonable job. The usual mistakes are sealing over old sealant, sealing a damp joint and using too much.
Honest limits
Some problems need a builder, plumber or other trade rather than us:
- Cutting new joints into brickwork, which is building work rather than sealant work
- Render that’s blown, hollow or coming away
- Cracking across the wall rather than at a joint
Not sure which it is? You can phone 0345 464 0079 or email us and we will tell you honestly.
What we seal
- Copings & trims
- Concrete & block
- Render & cladding joints
- Joints between brick and frames
- Brickwork movement joints
- Façade panels
Landlord and commercial work in Great Horwood
Letting agents and landlords in Great Horwood can book us as well as householders. Resealing between tenancies is a simple way to keep a property in good order.
Letting agents often deal with us directly. Send the address, what’s needed and the access arrangements and we will give you a quote.
External mastic in Great Horwood: local notes
The South East is one of the drier parts of the UK, though outdoor sealant still has to go onto a dry joint, so the forecast decides the day. With historic houses such as Claydon House (about 4.9 miles south-west) nearby, there’s older building stock in the area around Great Horwood as well as newer homes. Where a home is older, older walls and rooflines need a sealant that moves with them and suits the material.
Schools such as Great Horwood Church of England School are buildings too, and movement joints, cladding joints and gutters on larger buildings need the same care as a house’s.
Great Horwood is about 5 miles east of Buckingham, in Milton Keynes. Every kind of property in Great Horwood is covered for external mastic, old or new, large or small. Every job comes with our one-year guarantee. Across Milton Keynes, we cover 73 places, Great Horwood among them. Oxford is on our list too, about 22 miles from Great Horwood.
Our applicators cover all of MK17 for external mastic. If you need external mastic at a property on High Street, The Green and Willow Road or anywhere close by, we can help. If you’re just outside Great Horwood, we cover Little Horwood (1 mile east), Nash (2 miles north), Winslow (2 miles south), Whaddon (3 miles north-east) and Swanbourne (3 miles south-east). Within a short drive, we also cover Milton Keynes (6 miles north-east), Bletchley (6 miles east), Newport Pagnell (10 miles north-east), Bletchley and Fenny Stratford (7 miles east), Furzton (5 miles north-east) and Whitehouse (5 miles north-east).
Near you in Great Horwood
Locally, jobs take us to homes and businesses close to Sir Thomas Fremantle School and The Crown pub, among other places. Nearby you’ll also find Buckingham Community Hospital (5 miles north-west) and Drayton Parslow Mound (4.2 miles south-east). Green spaces nearby include Buckingham Sand Pit.
Quotes for external mastic in Great Horwood
We quote each job individually. This is what makes a difference:
- The product the joint needs
- The old material and how stubborn it is
- The amount of work
- How easy the joints are to reach
There are no prices on our website, because the cost depends so much on the job itself. For a quick quote, please call 0345 464 0079 or email us.
What we need to know
A few details help us give you an accurate quote. When you ask for a quote, tell us:
- Whether it’s a home or a business
- The problem you’ve noticed
- How we’d reach the joints
- Any previous sealing or DIY work
A good description makes for an accurate quote. Tell us where the job is, what’s wrong and how much there is.
What we’re called out for in Great Horwood
Weeds, moss and debris in a joint are a sign the sealant has gone. Dirt and roots then trap moisture in the joint.
The most common problems we see are:
- Sealant that has lost its bond to the brick or render
- Gaps where render, brick and frames meet
- Weeds or debris growing in open joints
- Panel joints letting water in
For an older house near a landmark such as Church of St James, an extension built onto an older house moves differently, and the joint between them takes the strain.
Before you book anyone
- What insurance they hold
- How long the guarantee is
- Is VAT in the price?
- What happens if they find a problem under the old sealant
Towns and villages near Great Horwood
Other services in Great Horwood
How to look after the new joints
So the new joints stay in good condition:
- Have failed joints looked at early
- Ask before painting over external sealant
- Clear growth from the base of walls and joints
- Keep water from gutters off the wall
Make sure anyone working on the wall later knows where the movement joints are. They must stay as flexible joints, never rendered or pointed over.
Leave a failed movement joint and water keeps getting into the wall. That can lead to damp patches, staining and frost damage.