Hertfordshire · England
External Mastic in Poynders End
Sealing brickwork movement joints, render, cladding and façade joints for Poynders End, backed by a one-year guarantee. Call for a quick quote.
- Sealant pulling away from one side of the joint
- Leaking joints around cladding and façade panels
- Weathered mastic that no longer stretches
About our external mastic in Poynders End
Where two different materials meet, such as brick and render or blockwork and metal, they move at different rates. A flexible exterior sealant takes up that movement where mortar or filler would crack. We’re often asked to deal with joints pointed up with cement by mistake and plants rooting in failed movement joints, across brickwork movement joints, joints between brick and frames and copings & trims.
External sealant needs dry, clean surfaces, so work around Poynders End is planned for dry weather. Tell us about access to all sides of the building, including outbuildings and garages.
There’s a 12-month guarantee on every job.
- Place
- Poynders End (SG4)
- Region
- Hertfordshire
- Guarantee
- A year, on every job
- Price
- A clear price before any work starts
- Telephone
- 0345 464 0079
- Last updated
- 26 October 2026
What we’re called out for in Poynders End
A lot of failed joints come down to preparation: joint faces that were dusty or damp, unprimed where they needed it, or still carrying old sealant. The new sealant then lets go long before it should.
Common reasons people contact us are:
- Moss and dirt in joints with no sealant left
- Failed seals between different materials
- Joints where the bead has come unstuck
- Hard, crazed mastic that has stopped moving
Rented homes near Stevenage station change hands often, and outside joints that have cracked can let damp into a rental, so check them between lets.
Before booking anyone
- What the cure time is
- Is the old sealant removed completely?
- How the colour is chosen
- What the quote includes, VAT included or not
Poynders End: your questions answered
Will you come out to Poynders End?
Yes, we do. We work across London and the South East, and smaller places are part of that. Longer journeys are simply planned in advance.
Can you do external mastic in Poynders End?
Yes. Our work covers London and the South East, and Poynders End is part of that. You can ring 0345 464 0079 or email us and let us know what needs doing.
Do you work at height?
That depends on the building and the joints. Where joints can be reached safely, we will do them. Tell us about the building and we’ll confirm what access is needed.
Can new sealant go over the old?
No, and we never do. It may look fine at first, but the new layer lifts away from the old one. The old sealant has to come out completely.
Do you take out the old sealant first?
Yes. All of the old material is cut out and the joint cleaned before resealing.
Do you hold any approvals?
Yes. We hold ARBOMaster approved applicator status and we are fully insured too.
Where do you work from?
We work from Crawley. We cover Poynders End and the rest of Hertfordshire.
Will you leave a mess?
No. We protect the surfaces around the joints, and we clear up the old sealant and our materials before we leave.
Outside joints around Poynders End
Historic houses like Knebworth House (about 3.5 miles south-east) are a reminder that the area around Poynders End has older buildings as well as new. In older buildings, older brick and stone need a sealant that suits them, at the right joint depth. 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.
For an older house near a landmark such as Church of St Martin, an extension built onto an older house moves differently, and the joint between them takes the strain. For site and facilities teams at buildings such as Preston Primary School, larger buildings have long runs of movement joint that eventually need resealing.
Poynders End is about 3 miles south of Hitchin, in Hertfordshire. From the centre of Poynders End to the outskirts, we cover external mastic for every kind of property, from flats and houses to offices and hotels. Poynders End is one of 381 towns and villages in Hertfordshire where we work for external mastic. There’s also a page for London, roughly 29 miles from Poynders End.
Every address in SG4 is within our area for external mastic, from the main roads to the quietest streets. We also cover the places around Poynders End: Temple Dinsley (1 mile south-west), Preston (1 mile west), Langley End (1 mile south-east), Little Almshoe (1 mile north-east) and St Ibbs (1 mile north). Within a short drive, we also cover Hemel Hempstead (13 miles south-west), Stevenage (4 miles east), St Albans (11 miles south), Welwyn Garden City (8 miles south-east), Harpenden (7 miles south-west) and Hitchin (3 miles north).
What’s near Poynders End
Around Poynders End, our work takes us to homes and buildings near The Red Lion Public House and the streets around them. For rail, the closest station is Stevenage station, about 2.8 miles east of the centre. Nearby you will also find Wymondley Castle (2.8 miles north-east) and North Hertfordshire Museum (2.8 miles north). Green spaces nearby include Purwell Ninesprings and Markham's Hill.
Work for landlords, hotels and businesses
A neglected joint can let water reach the structure, which is a bigger problem in a rented property. Keeping joints in good order is simple maintenance that we can handle for you.
Businesses can book us for washrooms, kitchens, offices and more. On commercial sites, working times can be discussed when we quote.
Should I try it myself first?
What a professional job adds is preparation and the right product. Joints are cleaned back to sound surfaces and dried, and the sealant is matched to the joint and its conditions, then guaranteed for a year.
Too much sealant is as bad as too little. A thick, smeared bead looks untidy and does not move well, and getting the depth right matters as much as the look.
What happens on the day
Our applicators work methodically: protection first, then preparation, sealing and a tidy-up. For most jobs that takes a few hours for a handful of joints, longer for a whole elevation. For a village or hamlet like Poynders End, the journey is planned in advance: tell us about narrow lanes, gates, long drives and where we can park. Everything for the job comes with us, so a second trip is avoided where possible.
- We start by checking each joint, agreeing the ones to redo and how we’ll reach them.
- The old mastic and anything lodged in the joint is removed.
- We clean both faces of the joint and prime them where the product calls for it.
- Backing rod goes in next, setting the depth and keeping the sealant off the back of the joint.
- A flexible exterior sealant is applied and tooled in a colour to suit the wall.
Preparing for the visit
- On commercial sites, let us know about site rules
- Mention any parking rules near the property
- Tell us about any water getting in
Get a quote
Every job is quoted individually. Simply call 0345 464 0079 or drop us an email and describe the job, and pictures are welcome.
Read more
Surface by surface
Cladding and façade panels
Panels heat up and cool down quickly, so the joints work hard every day. The sealant is chosen with that in mind.
Copings and trims
A failed coping joint lets water into the top of the wall. Resealing them is a small job that protects a lot.
Why act early in Poynders End
Sealing over the top of old mastic does not hold for long. New sealant does not bond well to old, weathered sealant, so the old joint is cut out fully first. In a small place like Poynders End, homes can be exposed to wind and rain, which finds any gap, and damp in older walls is slow to dry out.
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 Poynders End clients choose us
- We never seal over old sealant
- Every job guaranteed for a year
- You choose the colour before work begins
- Fully insured
See our cost guide and what customers say.
Keeping the joints in good condition
To keep the joints looking good and working properly:
- Make sure movement joints aren’t pointed over
- Deal with leaking gutters that soak the joints below
- Walk round the building once a year and look at the joints
- Show decorators and builders where the movement joints are
Keep the joints clear of soil, plants and climbing growth. Anything that holds water against the joint wears it out sooner.
Once a joint cannot move, the wall finds another way, generally as cracking in the brickwork or render nearby. Catch it early and you reduce the risk.