Hertfordshire · England
Chaulden External Mastic
Sealing brickwork movement joints, render, cladding and façade joints for householders, landlords and businesses in Chaulden. ARBOMaster approved applicators, fully insured, with a 12-month guarantee.
- Weeds or debris growing in open joints
- Sealant that has lost its bond to the brick or render
- Failed sealant between panels on a façade
External mastic for homes and businesses in Chaulden
We cut out failed sealant, set the joint depth with closed-cell backing rod and reseal with a low-modulus exterior sealant. We pick a colour that sits well with the wall. If you have leaking joints around cladding and façade panels and moss and dirt in joints with no sealant left, we can help.
Houses in smaller places like Chaulden can stand more in the open than those in a built-up town, so exposed walls and rooflines take more wind-driven rain. Joints on those sides are usually the first to go.
Big or small, you get the same 12-month guarantee in Chaulden and across Hertfordshire.
- Where
- Chaulden (HP1, HP3)
- Region
- Hertfordshire
- Cover
- 12 months on all our work
- Price
- A clear price before we start
- Call
- 0345 464 0079
- Last updated
- 26 October 2026
When to call us in Chaulden
Many joints fail because they were sealed too deep or with nothing behind them. If the sealant sticks to the back as well as the sides, it can’t stretch and tears as soon as the joint widens.
The problems people usually mention when they call are:
- Failed sealant between panels on a façade
- Weeds or debris growing in open joints
- Sealant that has lost its bond to the brick or render
- Water getting into walls through failed joints
For site and facilities teams at buildings such as Chaulden Junior School, larger buildings have long runs of movement joint that eventually need resealing.
Before you book anyone
- What product goes in the joint
- Which colour the sealant will be
- Is the old sealant removed completely?
- How the joint is cleaned and prepared
When it isn’t the sealant
In fairness, there are a few things sealant won’t fix:
- Cracking across the wall rather than at a joint
- Render that’s blown, hollow or coming away
- Rising or penetrating damp from elsewhere in the wall
Not sure which it is? You can call 0345 464 0079 or send us an email and we will tell you honestly.
Joints and surfaces we work on
- Joints between brick and frames
- Brickwork movement joints
- Render & cladding joints
- Concrete & block
- Façade panels
- Copings & trims
How the job changes by surface
Brickwork movement joints
Clay brickwork grows slightly over its life and moves with the weather. The movement joint takes that up, so its sealant has to stay flexible.
Joints between dissimilar materials
Different materials may need different primers. Both surfaces are cleaned and primed as the product requires.
Chaulden questions
Can you help a landlord with a rental near Hemel Hempstead station?
Yes, landlords and agents are among the people we work for. Just call 0345 464 0079 or drop us an email with the address and what needs doing, and we will give you a clear quote.
Is it worth replacing old sealant in an older home in Chaulden?
Generally, yes, if it’s cracked, shrunk, mouldy or coming away. The key is cutting all the old sealant out, as new sealant won’t bond to it.
What is a movement joint?
A movement joint is a planned break in the wall that absorbs expansion and shrinkage. It should be filled with flexible sealant, never mortar.
Do you come to Chaulden?
Yes, we do. Chaulden is part of the area we cover.
Is it OK to fill a movement joint with cement?
No. Rigid materials cannot move with the wall and the joint fails. If it has already been filled, we can generally cut it out and reseal it.
How do you reach high-level joints?
That depends on the building and the joints. Where joints can be reached safely, we’ll do them. Give us some details and we’ll confirm the access.
Do I need to be at home?
It depends on the job. Inside work needs someone to give us access, and for outside work we will agree access with you when we book.
Do you guarantee your work?
Yes, always. Each job is guaranteed for twelve months, wherever you are.
What happens on the day
The work is kept neat and contained to the joints we are treating, so you can get on with your day. The job normally takes a few hours for a handful of joints, longer for a whole elevation, and we explain the cure time before we leave. For a job in Chaulden, we agree the time, the access and parking before the day. If the work is outside, the weather plays a part, as sealant needs a dry surface.
- First, the joints are inspected and the access agreed.
- Every bit of old sealant and any mortar or debris is cut out.
- Joint faces are cleaned back and primed if the sealant needs it.
- We fit closed-cell backing rod to control 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
- Keep pets and children clear of the area while we work
- Let us know about parking restrictions
Get a quote
For a quote, phone 0345 464 0079 or email us with the location and a short description of the problem. We’ll give you a clear price before any work starts.
Read more
Places near Chaulden
More services for Chaulden
Chaulden buildings and the weather
Chaulden is part of Hemel Hempstead, one of the post-war new towns. Homes here were built in phases, many of them in the post-war decades, so whole streets can have gutters, trims and wall joints reaching the end of their life together. London and the South East are among the drier parts of the UK, though outdoor sealant still has to go onto a dry joint, so the forecast decides the day.
For an older house near a landmark such as St Stephen, older walls, gutters and the joints where extensions meet them need a flexible sealant. If you let a flat or house near Hemel Hempstead station, split movement joints are easy to miss on a rental until damp shows inside.
Chaulden is about 2 miles west of Hemel Hempstead, in Hertfordshire. From the centre of Chaulden to the outskirts, we cover external mastic for every kind of property, from flats and houses to offices and hotels. Our Hertfordshire coverage runs to 381 places, and Chaulden is one of them. London is on our list too, around 25 miles away.
Work in HP1 and HP3 works the same way as everywhere else we cover. If you need external mastic at a property on Furze Road, London Road and Sundew Road or anywhere close by, our applicators can take on the job. With the A41 close by, Chaulden is easy for our applicators to reach. We also cover the places around Chaulden: Bourne End (1 mile west), Fields End (1 mile north-west), Potten End (2 miles north-west), Frithsden (2 miles north-west) and Bulstrode (2 miles south). We also work in nearby towns such as Watford (7 miles south-east), St Albans (7 miles east), Welwyn Garden City (14 miles east), Harpenden (8 miles north-east), Hatfield (12 miles east) and Borehamwood (12 miles south-east).
What’s near Chaulden
Typical jobs here are in homes near Three Horse Shoes Public House, John F Kennedy Catholic School and Gadebridge Park. Chaulden’s nearest station is Hemel Hempstead station, roughly 0.8 miles south-east. Other landmarks nearby include Hemel Hempstead Hospital (1.4 miles east). The countryside around Chaulden includes Long Deans.
Why it’s worth doing now in Chaulden
It often makes sense to reseal all the failing joints on an elevation together. They’ve weathered the same way, and access only has to be arranged once. Around Chaulden, water from a failed joint in an older home can soak into timber and plaster, and that’s a much bigger job than renewing the sealant.
There are no prices on our website, because each job is priced on what it involves. For a quick quote, please call 0345 464 0079 or drop us an email.
What you get with us
- You choose the colour before work begins
- Approved under the ARBOMaster scheme
- Any old sealant cut out fully, not covered over
- We are fully insured
Take a look at what affects the cost and our reviews.
Should I try it myself first?
Overfilling a joint is a classic DIY mistake. A heavy bead looks messy and copes badly with movement, and the joint depth matters as much as the finish.
Sealing over old silicone is the commonest DIY error. New silicone will not bond to old, so it lifts and traps water and mould underneath. All the old material has to come out first.
Work for landlords, hotels and businesses
If you manage several properties in or around Chaulden, several properties can be quoted together. Just tell us the addresses and what each one needs.
We also work for businesses, from offices to washrooms and kitchens. On commercial sites, working times can be discussed when we quote.