Hertfordshire · England
External Mastic in Staines Green
We cover Staines Green for sealing brickwork movement joints, render, cladding and façade joints. Old material cut out, joints cleaned and sealed neatly and every job guaranteed for a year.
- Sealant pulling away from one side of the joint
- Damp patches traced to an open external joint
- Failed sealant between panels on a façade
External mastic in Staines Green
On houses, flats and commercial buildings across Staines Green, we reseal joints in brickwork, render, cladding and façade panels. Every joint gets the same careful preparation: clean joint faces and the right depth. If you’re dealing with moss and dirt in joints with no sealant left and failed sealant between panels on a façade, we can put it right.
Outside joints can only be sealed when they’re dry, so work in Staines Green is booked around the forecast. 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 is not right with it, phone 0345 464 0079 or email us.
- Where
- Staines Green (SG14)
- Region
- Hertfordshire
- Guarantee
- A year, on every job
- Quotes
- A clear price before work begins
- Telephone
- 0345 464 0079
- Last updated
- 26 October 2026
DIY versus a professional finish
Overfilling a joint is a classic DIY mistake. A heavy bead looks messy and copes badly with movement, and getting the depth right matters as much as the look.
What a professional job adds is preparation and the right product. Joints are cleaned back to sound surfaces and dried, and the sealant is chosen for how the joint moves and where it is, then guaranteed for a year.
Looking after it afterwards
A little care helps the new joints last. Our advice:
- Deal with leaking gutters that soak the joints below
- Never let anyone fill a movement joint with mortar
- Have failed joints looked at early
- Point out the joints to other trades
Keep pressure washers away from the sealant. A strong jet can damage the edges of the bead and let water in behind.
Water getting behind cladding or render can go unnoticed for a long time. By the time there’s a damp patch, the damage can be well established so early resealing is worth it.
What happens if it’s left?
The longer a joint stays open, the more water the wall takes in. Wet masonry is more easily damaged by frost, so the damage spreads beyond the joint. Where a wall is exposed, as many are in small places like Staines Green, wind-driven rain gets into any failed joint, and older walls, once damp, take a long time to dry.
The cost reflects the work involved, not a rough estimate. That’s why we ask about the job first.
Why Staines Green customers choose us
- Tidy, careful work
- Sanitary silicone with an anti-fungal additive in wet areas
- Arbo and Everbuild products
- A 12-month guarantee on all work
See our cost guide or what customers say.
What we can’t put right
It helps to know what we can’t do too:
- Cracking across the wall rather than at a joint
- Loose or hollow render, which needs re-rendering
- Damp from another source, such as a leaking gutter or a bridged damp-proof course
If in doubt, phone 0345 464 0079 or email us and we will say what we think before booking.
Joints and surfaces we work on
- Copings & trims
- Render & cladding joints
- Façade panels
- Joints between brick and frames
- Concrete & block
- Brickwork movement joints
Staines Green buildings and the weather
The South East is one of the drier parts of the UK, though outdoor sealant still has to go onto a dry joint, so the forecast decides the day. Historic houses like Digswell House (about 4.2 miles north-west) are a reminder that the area around Staines Green has older buildings as well as new. Where a home is older, older walls and rooflines need a sealant that moves with them and suits the material.
If you look after a building such as Hertingfordbury Cowper Primary School, movement joints, cladding joints and gutters on larger buildings need the same care as a house’s. Homes close to Church of St Mary and St John include some older properties, and older walls, gutters and the joints where extensions meet them need a flexible sealant. For landlords with property near Hertford North station, failed wall and movement joints let damp in, so they’re worth checking between tenancies.
Staines Green is about 2 miles west of Hertford, in Hertfordshire. Wherever you are in the SG14 postcode area, we can carry out external mastic at your property. Staines Green is one of 381 towns and villages in Hertfordshire where we work for external mastic. For nearby work, see our London page, about 20 miles away.
All of SG14 is covered for external mastic. Neighbouring places we cover for external mastic include Hertingfordbury (1 mile east), East End Green (1 mile south), Letty Green (1 mile south-west), Bayford (2 miles south) and Essendon (2 miles south-west). Within a short drive, we also cover Watford (15 miles south-west), Hemel Hempstead (15 miles west), Stevenage (9 miles north), St Albans (9 miles west), Bishop's Stortford (13 miles north-east) and Welwyn Garden City (3 miles west).
Local landmarks in Staines Green
Typical jobs here are in homes near The Sele School, Panshanger Park and White Horse Inn, among other places. The nearest railway station is Hertford North station, about 1.3 miles north-east of the centre. A little further out are Mcmullen & Sons Brewery Museum (1.8 miles east) and Hertford County Hospital (1.4 miles east). Not far away are Willowmead.
What we do, step by step
There is not much for you to do on the day. Point us to the joints and we’ll get on with it. The job generally takes a few hours to a few days, depending on the length of joint and the access from start to finish. Somewhere like Staines Green needs a little journey planning: let us know about lanes, gates and parking. We bring what the job needs, so it can be finished in one trip where possible.
- We start by walking round the building and agreeing the joints and the access.
- 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.
Getting ready for the visit
- Mention any sign-in or site rules at work premises
- Mention any leaks or damp you’ve noticed
- Mention any tricky access
Ask for a quote
Every job is quoted individually, so the first step is telling us about yours. Simply ring 0345 464 0079 or send us an email and describe the job and send pictures if you have them.
Related advice
Also near Staines Green
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How the job changes by surface
Concrete and blockwork
Wide joints in concrete need the depth controlling carefully. We size the backing rod to the gap.
Cladding and façade panels
Panel systems often rely on sealant between and around the panels. Each joint gets a sealant that suits the panel and its movement.
Work for landlords, hotels and businesses
Water getting past a failed joint can damage the building, which matters even more when someone else lives there. Keeping joints in good order is simple maintenance.
For anyone letting property in or around Staines Green, several properties can go on one quote. Just tell us the addresses and what each one needs.
Staines Green questions
Is Staines Green within the area you cover?
Yes, Staines Green is covered. Our work covers London and the South East, from towns to the smallest places. Longer journeys are simply planned in advance.
Is Staines Green in your area for external mastic?
Yes, Staines Green is within the area we cover. Our work covers London and the South East. Just phone 0345 464 0079 or drop us an email with a few details of the job, and we will give you a clear price.
Do you remove the old sealant?
Always. Sealing over the old bead is the commonest cause of early failure, so we never do it.
Why do you put foam in the joint first?
Backing rod goes into deeper joints as a matter of course. It controls the depth and stops the sealant bonding to the back, so the joint can move.
Can a movement joint be filled with mortar?
No. Rigid materials cannot move with the wall, 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’re based in Crawley, and we work across South East England, London and Scotland.
Do you do commercial work?
Yes. We work in offices, washrooms, hotels and other commercial premises, as well as homes. Working times can be discussed when we quote.
Can you reach joints on upper floors?
Each building is different. Send us photos and a rough idea of the height and we will confirm how they can be reached safely.