Buckinghamshire · England
Radnage External Mastic
External mastic in Radnage from a team with over 20 years’ experience. 180+ five-star Google reviews and a 4.9 rating.
- Cracked joints where brick meets render or frames
- Movement joints with cracked, split or missing sealant
- Rigid filler in a joint that should flex
Keeping the joints in good condition
No joint lasts for ever, but care makes a real difference. A few tips:
- Avoid pressure-washing directly into sealant joints
- Ask before painting over external sealant
- Walk round the building once a year and look at the joints
- Keep water from gutters off the wall
Follow the cure time we give you before the joint is knocked or disturbed. The surface skins over quickly, but full cure takes longer.
Gaps, plants or missing sealant in a joint are worth getting looked at. Early work is quicker and leaves a better finish.
External mastic for homes and businesses in Radnage
Short cuts in external joints show up within a season or two. Overfilled joints, missing backing rod and sealant laid over old sealant rarely last long. We strip the joint back and start again. We’re often asked to deal with gaps where render, brick and frames meet and joints where the bead has come unstuck, on joints between brick and frames, copings & trims and façade panels.
Around Radnage, older buildings can be stone, brick or timber-framed, many with extensions added later. Where one material meets another is where water generally gets in, and they need the right sealant at the right depth.
There’s a 12-month guarantee on every job, whatever its size.
- Where
- Radnage (HP14)
- Wider area
- Buckinghamshire
- Cover
- One year on every job
- Quotes
- Quoted before any work starts
- Phone
- 0345 464 0079
- Page updated
- 26 October 2026
External mastic in Radnage: local notes
Historic houses like West Wycombe Park House (about 3.2 miles south-east) are a reminder that the area around Radnage has older buildings as well as new. Where a home is older, older walls and rooflines need a sealant that moves with them and suits the material. London and the South East are among the drier parts of the UK, but outside sealant still needs a dry, clean surface, so outdoor work is planned around the forecast.
Homes close to Church of St Mary include some older properties, and older walls, gutters and the joints where extensions meet them need a flexible sealant. Rented homes near Saunderton station change hands often, and split movement joints are easy to miss on a rental until damp shows inside.
Radnage is about 6 miles north-west of High Wycombe, in Buckinghamshire. Homes, rented property, offices and hotels in Radnage can book us for external mastic, old or new, large or small. Every job comes with our 12-month guarantee. Radnage is one of 263 towns and villages in Buckinghamshire where we work for external mastic. For nearby work, see our Reading page (16 miles or so).
Jobs for external mastic in HP14 is quoted and booked the same way as anywhere else. Streets in the area include Bottom Road, Bower's Lane and Bennett End Road. If you’re just outside Radnage, we cover Bennett End (1 mile west), Bledlow Ridge (1 mile north-east), The City (1 mile south), Rout's Green (1 mile north) and Waterend (1 mile south-west). Further out, we also cover Aylesbury (10 miles north), High Wycombe (6 miles south-east), Chesham (11 miles east), Marlow (8 miles south-east), Amersham (11 miles east) and Beaconsfield (10 miles south-east).
Landmarks near Radnage
Typical jobs here are in homes near The Three Horseshoes Inn. The closest station to Radnage is Saunderton station, roughly 1.6 miles east. A little further out are Wycombe Hospital (5.5 miles south-east). Green spaces nearby include Yoesden and Bald Hill.
Do you need external mastic in Radnage?
Many joints fail because they were sealed too deep or with nothing behind them. Sealant bonded to three sides has nowhere to go and rips as the joint opens.
Any of these means the joints need attention:
- Leaking joints around cladding and façade panels
- Weeds or debris growing in open joints
- Cracked joints where brick meets render or frames
- Joints pointed up with cement by mistake
Managing a site like Radnage Church of England Primary School? Then its movement joints, gutters and trims need looking after like any other building’s.
What to look for in a quote
- What product goes in the joint
- How hidden problems are handled
- When the joint can take water or movement
- What the quote includes, VAT included or not
What we do, step by step
Good joint work is mostly preparation, and we do not rush it. Joints are cleaned back and dried before anything new goes in. In total, it normally takes a few hours to a few days, depending on the length of joint and the access. In a small place like Radnage, access is generally the main thing to plan. If the job is outside, mention outbuildings, exposed walls and how to reach them.
- Each joint is checked and the colour of the new sealant agreed.
- 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.
- A low-modulus exterior sealant is gunned in and tooled to a neat finish.
Getting ready for the visit
- Let us know if you’ve seen damp or leaks
- Mention if the joints have been sealed before
- Clear the area around the work
Get a quote
To get a quote, call 0345 464 0079 or drop us an email with the location and a short description of the problem. We will give you a clear price before any work starts.
Related advice
Landlord and commercial work in Radnage
A neglected joint can let water reach the structure, which is a bigger problem in a rented property. Resealing at the right time is simple maintenance that we can handle for you.
We work for landlords and agents as well as householders. Sealant work between tenants keeps a property looking cared for before the next move-in.
Questions from Radnage
Do you cover smaller places like Radnage?
Yes, smaller places are covered as well as towns. Our work covers London and the South East. Let us know about access, parking and anything unusual about getting there when you book.
Can you do external mastic in Radnage?
Yes, Radnage is within the area we cover. Our work covers London and the South East. You can call 0345 464 0079 or email us and let us know what needs doing, and we’ll give you a clear price.
Should I try DIY first?
Some simple jobs can be done by a careful DIYer. Most DIY failures come from sealing over old material, wet joints or too much sealant.
Where are you based?
We work from Crawley. Our applicators cover Radnage, along with the rest of our area.
Do you guarantee your work?
Yes, for a year. If there’s a problem with our work in that time, tell us and we’ll put it right.
Can you reach joints on upper floors?
It depends on the height and the site. Low-level joints are straightforward; for higher ones, send details and we’ll confirm the access.
When will the joints need doing again?
There’s no fixed answer: joints on exposed walls or with a lot of movement age sooner. A yearly look will tell you when they need doing. Our work comes with a 12-month guarantee.
I rent my home. Can I book you?
Yes, though it’s best to check with your landlord first. Landlords are often happy for the work to be arranged.
Why act early in Radnage
Mortar or ordinary filler might look like a quick way to close an open joint, but it locks the joint solid. The wall then cracks somewhere else. The correct repair is a flexible sealant with the right backing. Around Radnage, older homes often have timber in their floors and frames, where water from a failed joint can cause rot if it’s left.
Combining jobs into one visit usually makes better use of the time than several visits. You will get one clear quote for the whole job.
Why choose Mr Mastic in Radnage
- We leave the area clean and tidy
- Full insurance on every job
- 4.9 on Google from 180+ five-star reviews
- Old sealant always removed completely
Read what affects the cost or our reviews.
What sealant work cannot fix
To be straight with you, there are a few things sealant won’t fix:
- Failed render or damaged cladding panels
- Damp from another source, such as a leaking gutter or a bridged damp-proof course
- Movement that’s more than a sealant joint can take
If in doubt, ring 0345 464 0079 or email us and we’ll say what we think.
Where we work in Radnage
- Brickwork movement joints
- Concrete & block
- Joints between brick and frames
- Render & cladding joints
- Copings & trims
- Façade panels
Surface by surface
Joints between dissimilar materials
Where a frame or panel meets masonry, water often finds a way in. We cut out the old sealant and reseal with a product suited to both surfaces.
Concrete and blockwork
Concrete and block walls shrink as they dry and move with temperature. We reseal their joints with backing rod and a flexible product.