Essex · England
External & façade joints in Sandon, Essex
Movement joints in Sandon need attention? We remove the old material, prepare the joints and seal them properly, and the work is guaranteed for a year.
- Weathered mastic that no longer stretches
- Cracked joints where brick meets render or frames
- Moss and dirt in joints with no sealant left
Leave it or put it right?
Pointing a movement joint with mortar might seem a neat fix, but it stops the joint moving. The wall then cracks somewhere else. A flexible sealant over backing rod is what the joint needs. In a small place like Sandon, 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. We’ll send you a clear quote for the lot.
Why Sandon customers choose us
- More than 20 years in sealant work
- 4.9 on Google from 180+ five-star reviews
- We leave the area clean and tidy
- We never seal over old sealant
Read our cost guide or our reviews.
How we handle external mastic in Sandon
We cut out failed sealant, set the joint depth with closed-cell backing rod and reseal with a low-modulus exterior sealant. The colour is chosen to suit the brick or render. We work on render & cladding joints, copings & trims and concrete & block, and people most often call us about rain getting behind render or cladding at a joint and sealant pulling away from one side of the joint.
External sealant needs dry, clean surfaces, so work around Sandon is planned for dry weather. Let us know about access to every wall, plus any garages or outbuildings.
We stand behind the work with a 12-month guarantee, so you are covered after we have gone.
- Location
- Sandon (CM2)
- Wider area
- Essex
- Guarantee
- A year, on every job
- Quote
- A clear quote up front
- Phone
- 0345 464 0079
- Updated
- 26 October 2026
Outside joints around Sandon
With historic houses such as Danbury Place (about 1.4 miles east) nearby, there’s older building stock in the area around Sandon as well as newer homes. In older buildings, older walls and rooflines need a sealant that moves with them and suits the material. Compared with the north and west, the South East gets less rain, though outdoor sealant still has to go onto a dry joint, so the forecast decides the day.
Homes close to Church of St Andrew include some older properties, and the joints between older walls, newer extensions and the roofline need a sealant that can move. If you look after a building such as The Sandon School, its movement joints, gutters and trims need looking after like any other building’s.
Sandon is about 2 miles south-east of Chelmsford, in Essex. Anywhere in CM2, we can carry out external mastic at your property. We cover 644 towns and villages across Essex, large and small.
Work in CM2 is quoted and booked the same way as anywhere else. We cover properties on Hall Lane, The Lintons and Gablefields and the roads around them. Close by, we work in Great Baddow (1 mile west), Butt's Green (1 mile south-east), Springfield (2 miles north), Danbury (3 miles east) and Little Baddow (3 miles north-east). We also work in nearby towns such as Basildon (10 miles south), Braintree (12 miles north), Brentwood (11 miles south-west), Maldon (7 miles east), Canvey Island (14 miles south) and Billericay (7 miles south-west).
Around Sandon
In Sandon, that means homes and buildings near Baddow Hall Junior School and The Crown Inn, among other places. Sandon’s nearest station is Chelmsford station, roughly 2.8 miles north-west. Other landmarks nearby include Baddow Hospital (1 mile south-west) and Peter Edwards Museum And Library (2.7 miles north-west). Green spaces nearby include Danbury Ridge Nature Reserves.
Signs you need external mastic in Sandon
Every building moves. Clay bricks expand slightly over their life, concrete and block shrink, and everything moves with temperature and wet. The sealant in the movement joints takes that strain.
Look out for these signs:
- Rigid filler in a joint that should flex
- Panel joints letting water in
- Joints with sealant missing in places
- Damp patches traced to an open external joint
If you let a flat or house near Chelmsford station, failed wall and movement joints let damp in, so they’re worth checking between tenancies.
What your quote should include
- When the joint can take water or movement
- How the surfaces are prepared before sealing
- Whether they seal over old material or remove it
- Which sealant they’ll use, and why
Aftercare tips
No joint lasts for ever, but care makes a real difference. A few tips:
- Look over the joints every year, ideally after winter
- Have failed joints looked at early
- Ask before painting over external sealant
- Avoid pressure-washing directly into sealant joints
Give the sealant the cure time we tell you before anything rubs against it. Most exterior sealants skin fast but take longer to cure right through.
Gaps, plants or missing sealant in a joint are worth getting looked at. Early work is quicker and leaves a better finish.
How we quote for external mastic
Jobs vary more than people expect. What affects the quote:
- Whether there’s mould to deal with
- Access and height
- Whether old sealant or filler has to be cut out
- The amount of work
The cost depends on the size of the job, how much old material has to come out and access to the work. You will have a clear quote before any work starts.
What to tell us for a quote
When you contact us, these details help:
- The address or postcode of the job
- A few photos by email, if you can
- What the problem is, such as mould, gaps, leaks or cracking
- If it’s domestic, commercial or a hotel
A good description makes for an accurate quote. Let us know the location, the problem and roughly how many joints.
Common questions in Sandon
Will you come out to Sandon?
Yes, smaller places are covered as well as towns. Our work covers London and the South East. Just mention lanes, gates or anything else about the route when you book.
Do you cover Sandon for external mastic?
Yes. Our work covers London and the South East, and Sandon is part of that. You can phone 0345 464 0079 or send us an email and let us know what needs doing.
Do you seal joints where cladding meets other materials?
Yes. The old joint is removed, both surfaces cleaned and primed where needed, and a flexible sealant applied. The colour is chosen to suit.
Will it make a mess?
Very little: the area around the joints is protected first, and we tidy up before we go.
Does someone need to be in?
That depends on where the joints are. For work indoors, someone needs to let us in, and for outside work we will agree access with you when we book.
Do you remove the old sealant?
Yes, every time. New sealant won’t bond properly to old, so any old material comes out before anything new goes in.
Will the new joint stand out?
We aim for a joint that suits the wall rather than one that jumps out. Colour is agreed with you before we begin, matched as closely as the range allows.
Where are you based?
Mr Mastic is based in Crawley. Our applicators cover Sandon, along with the rest of our area.
Surface by surface
Concrete and blockwork
Concrete and block walls shrink as they dry and move with temperature. Their movement joints are sealed over backing rod with a flexible sealant.
Joints between dissimilar materials
Different materials may need different primers. We prepare both faces so the sealant bonds properly.
More services for Sandon
Should I try it myself first?
Sealing over old silicone is the commonest DIY error. New silicone will not bond to old, so it peels away and traps moisture behind it. All the old material has to come out first.
If you’ve already had a go yourself, that is fine. We cut it out and start again, so just mention it when you contact us.
How it works
At the end, we look at the finished work together. The visit itself generally takes anything from a few hours to several days, depending on the building, depending on how much there is to do. In a small place like Sandon, access is normally the main thing to plan. For outside work, also let us know about exposed walls and any outbuildings involved.
- First, the joints are inspected and the access agreed.
- We cut out the old mastic and rake out anything in the joint.
- The faces are brushed clean and primed where the product requires it.
- Backing rod sized to the joint goes in to set the depth.
- We apply the sealant, tool it and check the whole run.
How to prepare
- Let us know if you’ve seen damp or leaks
- Where the joints are inside, avoid wetting them before we arrive
- Clear items away from the joints we are working on
Get a quote
Getting a quote is simple: let us know the job and the location and its rough size. Photos by email help us understand the job, and we will come back to you with a quote.