Surrey · England
Holmbury St Mary External Mastic
Sealing brickwork movement joints, render, cladding and façade joints in Holmbury St Mary, with a one-year guarantee on every job. Ask us for a quote.
- Rain getting behind render or cladding at a joint
- Movement joints filled with mortar instead of sealant
- Weeds or debris growing in open joints
How we handle external mastic in Holmbury St Mary
As ARBOMaster approved applicators, we choose exterior sealants to suit the joint and the surfaces. Some surfaces need a primer before sealing and we use one wherever it does. We work on brickwork movement joints, render & cladding joints and joints between brick and frames, and the jobs we see most are water getting into walls through failed joints and weeds or debris growing in open joints.
Outside joints can only be sealed when they’re dry, so work in Holmbury St Mary is booked around the forecast. Tell us about access to all sides of the building, including outbuildings and garages.
A 12-month guarantee comes as standard, so you’re covered after we’ve gone.
- Location
- Holmbury St Mary (RH5)
- Wider area
- Surrey
- Guarantee
- 12 months on all our work
- Price
- Quoted before any work starts
- Telephone
- 0345 464 0079
- Page updated
- 26 October 2026
When it isn’t the sealant
Honest advice matters more to us than a booking, so here’s what new sealant won’t do:
- Structural movement, which needs a surveyor or engineer
- Cutting new joints into brickwork, which is building work rather than sealant work
- Damp from another source, such as a leaking gutter or a bridged damp-proof course
If you’re not sure, just phone 0345 464 0079 or email us and we’ll give you a straight answer.
Joints and surfaces we work on
- Joints between brick and frames
- Copings & trims
- Render & cladding joints
- Brickwork movement joints
- Façade panels
- Concrete & block
For landlords and businesses
Housing providers, facilities teams and property managers book us too in Holmbury St Mary and across Surrey. We can quote a run of properties together.
We work for landlords and letting agents as well as homeowners. Resealing between tenancies is a simple way to keep a property in good order.
How it works
Our applicators work methodically: protection first, then preparation, sealing and a tidy-up. Typically it takes a few hours for a handful of joints, longer for a whole elevation. Somewhere like Holmbury St Mary needs a little journey planning: let us know about lanes, gates and parking. Everything for the job comes with us, so a second trip is avoided where possible.
- We look at every joint and agree a colour to suit the wall.
- We take out the old sealant until the faces are sound.
- Closed-cell backing rod is pushed in so the sealant bonds to two sides only.
- Primer is applied wherever the sealant needs it.
- We gun in low-modulus sealant and tool it neatly.
How to prepare
- For indoor joints, keep the area dry beforehand if you can
- Plan for the work area to be out of bounds to pets and children
- Clear the area around the work
Ask for a quote
Every job is quoted individually, so the first step is telling us about yours. Simply call 0345 464 0079 or send us an email and describe the job.
Related advice
Keeping the joints in good condition
Joint life depends on how it’s used and looked after. We suggest:
- Ask before painting over external sealant
- Point out the joints to other trades
- Deal with leaking gutters that soak the joints below
- Have failed joints looked at early
Follow the cure time we give you before the joint is knocked or disturbed. Most exterior sealants skin fast but take longer to cure right through.
Leaks behind façade panels and render often go unseen. When it finally shows inside, the joint may have been open for years so early resealing is worth it.
What affects the quote in Holmbury St Mary
You will get a clear quote before any work starts. It takes into account:
- How much old sealant there is and how hard it is to remove
- Any mould that needs treating
- The amount of work
- How easy the joints are to reach
Homes and businesses are quoted the same way: the amount of work, the access and the products needed, along with when we can work on site. Call for a quick quote and we’ll explain what it covers.
Asking for a quote
When you contact us, it’s useful to know:
- Pictures of the joints, sent by email
- Roughly how big the job is
- Access, such as stairs, a lift or height
- If someone has resealed it before
Call for a quick quote, or email us if that’s easier. Tell us about the joints that need doing and we’ll talk you through the work.
Outside joints around Holmbury St Mary
With historic houses such as Polesden Lacey (about 4.8 miles north) nearby, there’s older building stock in the area around Holmbury St Mary as well as newer homes. In older buildings, older brick and stone need a sealant that suits them, at the right joint depth. Compared with the north and west, the South East gets less rain, but outside sealant still needs a dry, clean surface, so outdoor work is planned around the forecast.
For site and facilities teams at buildings such as Belmont Prep School, larger buildings have long runs of movement joint that eventually need resealing. Homes close to St Mary The Virgins Church include some older properties, and an extension built onto an older house moves differently, and the joint between them takes the strain. For landlords with property near Gomshall station, outside joints that have cracked can let damp into a rental, so check them between lets.
Holmbury St Mary is about 5 miles south-west of Dorking, in Surrey. Wherever you are in the RH5 postcode area, our applicators can take on external mastic. 395 places in Surrey are on our list, large and small. We also work in Crawley, around 11 miles away.
Work in RH5 is quoted and booked the same way as anywhere else. If you need external mastic at a property on Horsham Road and Felday Glade or a nearby road, our applicators can take on the job. Neighbouring places we cover for external mastic include Pitland Street (1 mile south), Peaslake (1 mile west), Farley Green (3 miles west), Ewhurst (3 miles south) and Ewhurst Green (3 miles south). We also work in nearby towns such as Guildford (8 miles north-west), Woking (11 miles north-west), Epsom (12 miles north-east), Horley (11 miles east), Redhill (11 miles east) and Ewell (13 miles north-east).
Around Holmbury St Mary
In Holmbury St Mary, that means homes and buildings near Wotton and Abinger Commons, The Volunteer pub and Hurtwood House and the streets around them. Holmbury St Mary’s nearest station is Gomshall station, about 2.1 miles north-west of the centre. Nearby you’ll also find Mesolithic Museum (0.7 miles north-east) and Abinger Castle (0.7 miles north-east). Green spaces nearby include Leith Hill and Silent Pool.
How the job changes by surface
Joints between dissimilar materials
Different materials may need different primers. Both surfaces are cleaned and primed as the product requires.
Concrete and blockwork
Blockwork and concrete shrink over time and move with the seasons. Their movement joints are sealed over backing rod with a flexible sealant.
Your questions about external mastic in Holmbury St Mary
Will you come out to Holmbury St Mary?
Yes, smaller places are covered as well as towns. Our work covers London and the South East. Let us know about access, parking and anything unusual about getting there when you book.
Can you do external mastic in Holmbury St Mary?
Yes, Holmbury St Mary is within the area we cover. Our work covers London and the South East. You can call 0345 464 0079 or send us an email and tell us what needs doing, and we’ll send you a clear quote.
Can a movement joint be filled with mortar?
No. Cement or mortar can’t stretch, so the joint stops doing its job. Where a joint has been mortared, it can often be raked out and sealed properly.
Where is Mr Mastic based?
We are a Crawley-based firm, with over 20 years’ experience. Our area covers South East England, London and Scotland.
What’s an expansion joint in brickwork?
Brickwork, render and cladding all move a little, and planned joints take up that movement. It’s closed with backing rod and a flexible sealant.
Do you take out the old sealant first?
Always. Sealing over the old bead is the commonest cause of early failure, so we never do it.
Do I need to be at home?
That depends on where the joints are. For work indoors, someone needs to let us in.
Do you guarantee your work?
Yes. All our work carries a one-year guarantee.
Should I try it myself first?
If you’ve already had a go yourself, that’s fine. We cut it out and start again, so tell us about it when you ask for a quote.
The difference is mostly in the preparation and the product. We take joints back to clean, dry surfaces, and the sealant is matched to the joint and its conditions, then guaranteed for a year.