Hertfordshire · England
External & façade joints in Wallington, Hertfordshire
Our applicators work in Wallington on sealing brickwork movement joints, render, cladding and façade joints. Old material cut out, joints cleaned and sealed neatly and a one-year guarantee.
- Cracked joints where brick meets render or frames
- Sealant pulling away from one side of the joint
- Rigid filler in a joint that should flex
How we handle external mastic in Wallington
We are ARBOMaster approved applicators, and each external joint gets a sealant suited to it. Some surfaces need a primer before sealing, and we do not skip that step. If you’re dealing with old sealant gone brittle and cracked and failed seals between different materials, we can put it right.
External sealant needs dry, clean surfaces, so work around Wallington is planned for dry weather. Let us know about access to every wall, plus any garages or outbuildings.
The work is covered for a year after we finish. If anything isn’t right with it, phone 0345 464 0079 or email us.
- Where
- Wallington (SG7)
- Wider area
- Hertfordshire
- Cover
- A year, on every job
- Quote
- A clear quote up front
- Telephone
- 0345 464 0079
- Updated
- 26 October 2026
Questions from Wallington
Can you do external mastic in Wallington?
Yes, Wallington 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 will give you a clear price.
Can you help a landlord with a rental near Ashwell & Morden station?
Yes, landlords and agents are among the people we work for, and several properties can go on one quote. You can call 0345 464 0079 or email us with the details for a clear quote.
Can you reach joints on upper floors?
It depends on the building. Tell us the height, the number of joints and what’s below them.
Do you guarantee your work?
Yes, for a year. If anything isn’t right with the work within the year, let us know and we’ll sort it.
Can you seal over the old sealant?
No. New silicone will not bond to old silicone, and it traps any mould or water underneath. It all has to come out first.
Do you remove the old sealant?
Yes. Sealing over the old bead is the commonest cause of early failure, so we never do it.
Will there be a smell?
Sometimes, a little. It fades as the sealant cures, and ventilation helps.
When is the sealant fully cured?
Different products cure at different speeds, so follow the cure time we give you.
DIY versus a professional finish
Not every job suits DIY: work at height, external movement joints, fire-rated sealant and large areas call for the right materials, safe access and experience.
The biggest DIY mistake is sealing over old sealant. New silicone will not bond to old, so it peels away and traps moisture behind it. Everything old must be removed first.
How the job changes by surface
Cladding and façade panels
Metal and composite panels move a lot with temperature, so the joints work hard every day. The sealant is chosen with that in mind.
Copings and trims
Coping joints that leak let water straight down into the wall. Resealing them is a small job that protects a lot.
Landlord and commercial work in Wallington
If you manage several properties in or around Wallington, jobs at different addresses can be quoted together. Just tell us the addresses and what each one needs.
In hotels, rooms out of use cost money, so the work can be planned room by room. We have worked in hotels as well as homes and businesses.
How to look after the new joints
A little care helps the new joints last. We recommend:
- Keep high-pressure jets off the joints
- Keep soil, plants and ivy away from the joints
- Fix overflowing gutters above sealed joints
- Walk round the building once a year and look at the joints
Look over the joints once a year, ideally after winter. Watch for splits, edges coming away or growth in the joint.
Small splits are the time to act. Then it’s a straightforward cut-out and reseal.
How it works
The work is kept neat and contained to the area we’re working on, so you can carry on as normal. The job normally takes a few hours for a handful of joints, longer for a whole elevation, and we tell you how long to leave it before we go. Somewhere as small as Wallington, access is often the only tricky part. 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.
- The exterior sealant is applied, tooled and checked along its length.
How to prepare
- Mention if the joints have been sealed before
- Keep pets and children clear of the area while we work
- Clear the area around the work
Getting a quote
Getting a quote is simple: let us know the job and the location and its rough size. A few pictures by email make the job easier to understand, and we’ll take it from there.
Advice
External mastic in Wallington: local notes
With historic houses such as Hinxworth Place (about 4.9 miles north-west) nearby, there’s older building stock in the area around Wallington as well as newer homes. In older buildings, older brick and stone need a sealant that suits them, at the right joint depth. The South East is one of 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 Ashwell & Morden station change hands often, and failed wall and movement joints let damp in, so they’re worth checking between tenancies.
Wallington is about 5 miles east of Letchworth, in Hertfordshire. If you need external mastic in Wallington, it’s easy to get a quote: please phone 0345 464 0079 or drop us an email. We cover Hertfordshire from our Crawley base. Our area takes in 381 places across Hertfordshire. We also work in Chelmsford, about 31 miles from Wallington.
Here we cover the SG7 postcode area for external mastic. Whether your property is on The Street and Kit's Lane or a nearby road, we can help. Other places close to Wallington include Clothall (2 miles south-west), Baldock (3 miles west), Weston (3 miles south-west), Walkern (5 miles south) and St Nicholas (5 miles south-west). Further out, we also cover Stevenage (6 miles south-west), Bishop's Stortford (14 miles south-east), Welwyn Garden City (14 miles south), Harpenden (15 miles south-west), Hitchin (7 miles west) and Hertford (13 miles south).
Local landmarks in Wallington
Wallington’s nearest station is Ashwell & Morden station, about 2.9 miles north of the centre. Well-known places in the area include Ashwell Village Museum (3.9 miles north-west) and Fairfield Hospital (5.6 miles west). Not far away are Hawkins Wood.
Signs you need external mastic in Wallington
Many joints fail because they were sealed too deep or with nothing behind them. Sealant bonded to three sides has nowhere to go and tears as soon as the joint widens.
These are the problems we are asked about most:
- Movement joints with cracked, split or missing sealant
- Rigid filler in a joint that should flex
- Panel joints letting water in
- Moss and dirt in joints with no sealant left
For an older house near a landmark such as Church of St Mary, older walls, gutters and the joints where extensions meet them need a flexible sealant.
What to look for in a quote
- What preparation is included
- Is the old sealant removed completely?
- What happens if they find a problem under the old sealant
- How long the guarantee is
Places near Wallington
What else we do in Wallington
What sealant work cannot fix
Honest advice matters more to us than a booking, so here’s what sealant cannot fix:
- Cracking across the wall rather than at a joint
- Cutting new joints into brickwork, which is building work rather than sealant work
- Failed render or damaged cladding panels
Not sure which it is? You can call 0345 464 0079 or drop us an email and we will tell you honestly.
Joints and surfaces we work on
- Façade panels
- Brickwork movement joints
- Copings & trims
- Render & cladding joints
- Concrete & block
- Joints between brick and frames