Hertfordshire · England
External Mastic in Brickendon
Our applicators work in Brickendon on sealing brickwork movement joints, render, cladding and façade joints. Old sealant removed completely, joints prepared properly.
- Hard, crazed mastic that has stopped moving
- Rain getting behind render or cladding at a joint
- Joints where the bead has come unstuck
Work for landlords, hotels and businesses
We work for landlords and agents as well as homeowners. Sealant work between tenants is a simple way to keep a property in good order before the next move-in.
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 that we can handle for you.
How we handle external mastic in Brickendon
External mastic is a job where short cuts show quickly. New sealant over old, joints packed with mortar and beads with no backing all tend to fail early. We strip the joint back and start again. We work on façade panels, concrete & block and brickwork movement joints, and common reasons people get in touch are gaps where render, brick and frames meet and damp patches traced to an open external joint.
External sealant needs dry, clean surfaces, so work around Brickendon is planned for dry weather. Tell us about access to all sides of the building, including outbuildings and garages.
A one-year guarantee comes as standard, so you are covered after we have gone.
- Place
- Brickendon (SG13)
- Wider area
- Hertfordshire
- Cover
- 12 months on all our work
- Price
- A clear quote up front
- Telephone
- 0345 464 0079
- Page updated
- 26 October 2026
How the visit works
At the end, we look at the finished work together and tell you how long to leave it. The work normally takes a few hours for a handful of joints, longer for a whole elevation, depending on the size of the job. In a small place like Brickendon, access is usually the main thing to plan. If the job is outside, mention outbuildings, exposed walls and how to reach them.
- We start by checking each joint, agreeing the ones to redo and how we’ll reach them.
- Old sealant and any debris are cut and raked out.
- The joint faces are cleaned and primed where the sealant needs it.
- Closed-cell backing rod is fitted to set the depth and stop three-sided bonding.
- The new sealant, chosen to suit the brick or render, is applied and tooled to a neat finish.
Getting ready for the visit
- Mention any parking rules near the property
- Plan for the work area to be out of bounds to pets and children
- Move anything stored near the joints
Getting a quote
For a quote, call 0345 464 0079 or drop us an email and tell us where the job is and what the problem looks like. We’ll give you a clear price before any work starts.
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Towns and villages near Brickendon
Also in Brickendon
Common problems we fix in Brickendon
Some movement joints have been pointed up with mortar, often by someone who didn’t know what it was for. The joint cannot move, so the wall cracks somewhere else instead.
Look out for any of the following:
- Weeds or debris growing in open joints
- Joints with sealant missing in places
- Sealant that has lost its bond to the brick or render
- Failed seals between different materials
In the older streets around Holy Cross & St Alban, the joints between older walls, newer extensions and the roofline need a sealant that can move.
Before booking anyone
- What product goes in the joint
- What happens if the job turns out different
- When the joint can take water or movement
- How long the guarantee is
External mastic in Brickendon: local notes
London and the South East are among the drier parts of the UK, yet outdoor joints still have to be sealed dry, so jobs are booked with the weather in mind.
Rented homes near Bayford station change hands often, and outside joints that have cracked can let damp into a rental, so check them between lets.
Brickendon is about 3 miles west of Hoddesdon, in Hertfordshire. Our applicators cover external mastic for householders, landlords and businesses in Brickendon and nearby. Our Hertfordshire coverage runs to 381 places, Brickendon among them. There’s also a page for London, about 18 miles away.
Every address in SG13 is within our area for external mastic. Neighbouring places we cover for external mastic include Wormley West End (2 miles south-east), Goose Green (2 miles east), Horns Mill (2 miles north), High Leigh (2 miles east) and Woollensbrook (2 miles north-east). Within a short drive, we also cover Watford (15 miles south-west), Stevenage (11 miles north), St Albans (11 miles west), Bishop's Stortford (13 miles north-east), Welwyn Garden City (6 miles north-west) and Harpenden (12 miles west).
What’s near Brickendon
Typical jobs here are in homes near The Farmer's Boy pub, among other places. Brickendon’s nearest station is Bayford station, about 0.6 miles west. A little further out are The National Speedway Museum (1.2 miles south-east) and Hertford County Hospital (2.8 miles north). The countryside around Brickendon includes Cheshunt Lake and Danemead.
Can I do it myself?
A careful DIYer can reseal a simple joint, such as a straightforward joint indoors. Where it goes wrong is sealing over the old bead, working on a wet joint or overloading the gap.
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.
How to look after the new joints
Aftercare is simple, and it makes a real difference:
- Show decorators and builders where the movement joints are
- Act on the first splits you see
- Keep soil, plants and ivy away from the joints
- Walk round the building once a year and look at the joints
Make sure anyone working on the wall later knows where the movement joints are. They should be kept open and resealed, not filled.
Water getting behind cladding or render can go unnoticed for a long time. When it finally shows inside, the joint may have been open for years.
Leave it or put it right?
The longer a joint stays open, the more water the wall takes in. Wet masonry is more easily damaged by frost, so the problem grows beyond the joint itself. Older cottages and farmhouses around Brickendon can have timber floors and frames, and water through a failed joint can rot timber if it’s left.
Rather than a set price list, we price the job in front of us: how many joints, what’s in them now and how we reach them. You’ll know the price before we begin.
Why choose Mr Mastic in Brickendon
- We never seal over old sealant
- You choose the colour before work begins
- Approved under the ARBOMaster scheme
- Full insurance on every job
Questions from Brickendon
Is Brickendon within the area you cover?
Yes, Brickendon is covered. We work across London and the South East, and smaller places are part of that. The journey is planned ahead, so it helps to know about access.
Do you work for landlords with property near Bayford station?
Yes, landlords and agents are among the people we work for, and several properties can be quoted together. You can call 0345 464 0079 or send us an email with the details for a clear quote.
Are you an approved applicator?
Yes. We’re an ARBOMaster approved applicator, the approved applicator scheme for Arbo sealants.
What is backing rod for?
Closed-cell backing rod sets the depth of the sealant and stops it sticking to the back of the joint. That way it bonds to the two sides only and can stretch.
Is the work guaranteed?
Yes, always. Each job is guaranteed for twelve months.
Do you remove the old sealant?
Always. Sealing over old sealant is the main reason resealing fails early, so we never do it.
Do I need to be at home?
We need access to the joints, so we’ll agree that with you when we book. Indoors, that normally means someone at home.
Do you work at height?
It depends on the building. Send us photos and a rough idea of the height and we will confirm how they can be reached safely.
Different surfaces, different methods
Joints between dissimilar materials
Where a frame or panel meets masonry, water often finds a way in. The old joint is removed and a sealant that bonds to both sides goes in.
Copings and trims
Copings expand and contract through the day, so a flexible sealant suits them best in all weathers.