Hertfordshire · England
Chenies External Mastic
Professional external mastic in and around Chenies, with old sealant always removed completely and a one-year guarantee.
- Moss and dirt in joints with no sealant left
- Cracked joints where brick meets render or frames
- Joints where the bead has come unstuck
External mastic in Chenies, done properly
Movement joints let brickwork, render and cladding expand and shrink without cracking. Its sealant has to flex with the building, season after season, and when it fails, the wall takes the strain and water finds a way in. Common call-outs are for movement joints with cracked, split or missing sealant and old sealant gone brittle and cracked, on joints between brick and frames, brickwork movement joints and render & cladding joints.
External sealant needs dry, clean surfaces, so work around Chenies is planned for dry weather. Tell us about access to all sides of the building, including outbuildings and garages.
We guarantee the work for a year. If there’s a problem with our work within the year, let us know and we’ll sort it.
- Place
- Chenies (WD3)
- Region
- Hertfordshire
- Cover
- A year, on every job
- Price
- A clear quote up front
- Telephone
- 0345 464 0079
- Page updated
- 26 October 2026
What affects the quote in Chenies
You will get a clear quote before any work starts. It’s based on:
- Whether there’s mould to deal with
- How many rooms, windows or areas are involved
- The number and length of the joints
- The type of sealant required
Instead of a standard rate, we price the job in front of us: the amount of work, the old material and the access. You’ll know the price before we begin.
Asking for a quote
When you call or email, these details help:
- The problem you’ve noticed
- Any access issues, like height or stairs
- Roughly how big the job is
- Where the property is
Every job is quoted individually. Just ring 0345 464 0079 or drop us an email with the details and send photos if you have them.
Landlords, agents and businesses in Chenies
A neglected joint can let water reach the structure, which matters even more when someone else lives there. Keeping joints in good order is simple maintenance.
Housing providers, facilities teams and property managers book us too. Several sites can be quoted together.
What external mastic looks like in Chenies
Historic houses like Chenies Manor House (about 0.2 miles south) are a reminder that the area around Chenies 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. 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.
Managing a site like Chenies School? Then its movement joints, gutters and trims need looking after like any other building’s. Letting a property close to Chalfont & Latimer station? Then outside joints that have cracked can let damp into a rental, so check them between lets.
Chenies is about 3 miles east of Amersham, in Hertfordshire. Chenies gets the same service as everywhere we cover: the old material taken out, joints prepared properly and a 12-month guarantee. Chenies is one of 381 towns and villages in Hertfordshire where we work for external mastic. London is on our list too, about 22 miles from Chenies.
Postcode districts we cover here for external mastic: WD3. Close by, we work in Latimer (1 mile west), Flaunden (1 mile north), Little Chalfont (2 miles west), Belsize (2 miles north-east) and Chorleywood (2 miles south-east). We also work in nearby towns such as Watford (6 miles east), Hemel Hempstead (6 miles north-east), St Albans (10 miles north-east), Harpenden (12 miles north-east), Hatfield (14 miles north-east) and Borehamwood (11 miles east).
Near you in Chenies
Locally, jobs take us to homes and businesses close to The Bedford Arms and St Clement Danes School and the streets around them. The nearest railway station is Chalfont & Latimer station, roughly 1.4 miles south-west of the centre. Other landmarks nearby include Amersham Fair Organ Museum (2.8 miles west) and Amersham Hospital (4 miles west). For a walk, there’s Sarratt Bottom nature reserve and Tumbling Bay.
How it works
On the day, we look over the joints with you first, so there are no surprises. Surfaces next to the work are protected before any work begins. The work usually takes anything from a few hours to several days, depending on the building. For a village or hamlet like Chenies, 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.
- 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.
- We gun in low-modulus sealant and tool it neatly.
How to prepare
- Let us know about parking restrictions
- Mention any leaks or damp you’ve noticed
- Let us know about earlier repairs to the joints
Ask for a quote
The more we know about the job, the more useful the quote. Let us know the location, the problem and roughly how many joints.
Advice
Also near Chenies
Also in Chenies
Should I try it myself first?
Some jobs are best left to a professional: work at height, external movement joints, fire-rated sealant and large areas need the right product, the right access and the right method.
The difference is mostly in the preparation and the product. Joints are cleaned back to sound surfaces and dried, and the sealant is matched to the joint and its conditions, and the work is guaranteed for a year.
Common problems we fix in Chenies
Using the wrong sealant is another common reason. A high-modulus or general-purpose sealant can be too rigid for a busy joint, so it pulls away from the edges.
Common reasons people contact us are:
- Brick movement joints where the sealant has split
- Joints pointed up with cement by mistake
- Old sealant gone brittle and cracked
- Failed seals between different materials
For an older house near a landmark such as Church of St Michael, older walls, gutters and the joints where extensions meet them need a flexible sealant.
What to look for in a quote
- Who does the work, and how experienced they are
- Which sealant they’ll use, and why
- Are they insured?
- When the joint can take water or movement
Surface by surface
Cladding and façade panels
Metal and composite panels move a lot with temperature, so the joint sealant has to cope with frequent movement. We choose the product to suit.
Brickwork movement joints
Brick walls have vertical movement joints to absorb expansion. They’re resealed over backing rod with a low-modulus sealant.
Your questions about external mastic in Chenies
Do you cover Chenies for external mastic?
Yes, Chenies is within the area we cover. Our work covers London and the South East. Just call 0345 464 0079 or drop us an email with a few details of the job, and we’ll send you a clear quote.
I let a flat near Chalfont & Latimer station. Can you help?
Yes, rental work is part of what we do. Just phone 0345 464 0079 or drop us an email and tell us about the property, and we will send you a clear quote.
Do the sealants smell?
That depends on the sealant. Some smell for a while, some hardly at all, and any smell fades as they cure.
Can you seal joints between render and window frames?
Yes. We cut out the old sealant, prepare both faces and reseal with a flexible exterior product. The colour is chosen to suit.
Do you do commercial work?
Yes. Hotels, offices and other businesses use us and we are fully insured.
Will the new joint stand out?
Exterior sealants are made in a range of colours, from greys and browns to whites and stone shades. We choose the closest to your brick or render.
Will the old sealant be removed?
Yes, every time. New sealant will not bond properly to old, so any old material comes out before anything new goes in.
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.
Leave it or put it right?
A properly done movement joint is an even line in a colour that suits the wall. A rushed bead with no backing looks untidy and does not last, so it pays to do it properly once. Around Chenies, older homes often have timber in their floors and frames, where water from a failed joint can cause rot if it’s left.
There are no prices on our website, because each job is priced on what it involves. Call for a quick quote and we will talk you through it.
Why book with us
- You choose the colour before work begins
- We never seal over old sealant
- Domestic, commercial and hotel work
- Sealant colour chosen to suit
Read our cost guide or our reviews.