Greater London · England
Lissenden Gardens External Mastic
Movement joints in Lissenden Gardens need attention? We remove the old material, prepare the joints and seal them properly, with a one-year guarantee.
- Sealant pulling away from one side of the joint
- Damp patches traced to an open external joint
- Gaps where render, brick and frames meet
About our external mastic in Lissenden Gardens
Joints between dissimilar materials, like brick against render or concrete against a steel frame, see movement from both sides. A flexible sealant bridges the two. We work on joints between brick and frames, render & cladding joints and brickwork movement joints, and people most often call us about sealant that has lost its bond to the brick or render and rain getting behind render or cladding at a joint.
Outside work in London starts with access: side passages, upper floors and where to park. For a home in Lissenden Gardens, tell us how high the joints are and how to reach the back of the building.
Our work is backed for twelve months, in Lissenden Gardens and everywhere else we cover.
- Location
- Lissenden Gardens (NW5, NW3, N19)
- Region
- Greater London
- Guarantee
- A year, on every job
- Price
- A clear price before any work starts
- Call
- 0345 464 0079
- Updated
- 26 October 2026
Looking after it afterwards
Looking after new joints is easy, and it makes a real difference:
- Wash walls gently around the sealant
- Check external joints each spring
- Clear growth from the base of walls and joints
- Have failed joints looked at early
If you have more work done on the wall, such as new render, cladding or an opening, show the contractor the movement joints. They must stay as flexible joints, never rendered or pointed over.
Small splits are the time to act. At that stage it’s a simple cut out and reseal.
The process
When we arrive, we start by going over the job with you, so you know exactly what we’re doing. Surfaces next to the work are protected before we start. The work normally takes a few hours to a few days, depending on the length of joint and the access. In Lissenden Gardens, flats, stairs and shared entrances are part of the routine. If the building has a concierge, managing agent or access rules, tell us when you book.
- We start by walking round the building and agreeing the joints and the access.
- 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.
- The exterior sealant is applied, tooled and checked along its length.
Preparing for the visit
- Tell us about any previous sealing or DIY attempts
- Let us know if you’ve seen damp or leaks
- On commercial sites, let us know about site rules
Ask for a quote
Every job is quoted individually. Simply call 0345 464 0079 or email us and describe the job and send pictures if you have them.
Read more
What we are called out for in Lissenden Gardens
Sunlight, wet weather and frost wear exterior sealant down. In time it goes hard, crazes on the surface and stops stretching, so the joint eventually tears or comes away from one side.
Signs it’s time to call us include:
- Movement joints with cracked, split or missing sealant
- Rain getting behind render or cladding at a joint
- Cracked joints where brick meets render or frames
- Weeds or debris growing in open joints
Letting a property close to Gospel Oak station? Then outside joints that have cracked can let damp into a rental, so check them between lets.
What your quote should include
- How much experience the applicator has
- Is VAT in the price?
- Which colour the sealant will be
- Whether they’re fully insured
Honest limits
New sealant can’t fix everything, and we’d rather say so up front. It won’t solve:
- Cutting new joints into brickwork, which is building work rather than sealant work
- Structural movement, which needs a surveyor or engineer
- Cracks in the bricks or render themselves, away from the joints
Not sure which it is? You can phone 0345 464 0079 or send us an email and we will tell you honestly before you book.
Where we work in Lissenden Gardens
- Joints between brick and frames
- Concrete & block
- Façade panels
- Render & cladding joints
- Brickwork movement joints
- Copings & trims
Common questions in Lissenden Gardens
Do you cover Lissenden Gardens for external mastic?
Yes. We work across London and the South East, and Lissenden Gardens is part of that. Just phone 0345 464 0079 or drop us an email with a few details of the job, and we’ll give you a clear price.
Is parking a problem for a job in Lissenden Gardens?
Parking in Lissenden Gardens, as in most of London, takes a little planning: a visitor permit or a bay close to the door helps a lot, so mention what’s available when you book.
How long does the job take?
It depends on the size of the job, but as a guide it takes anything from a few hours to several days, depending on the building. We will give you a better idea when we quote.
Can you work on commercial sites?
Yes. We work in offices, washrooms, hotels and other commercial premises, as well as homes. Working times can be discussed when we quote.
Is it OK to fill a movement joint with cement?
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.
Can you seal over the old sealant?
No, and we never do. It can look neat for a few weeks, but the new bead soon lifts. Removing the old sealant completely is the only lasting way.
How long should I leave it?
It depends on the product and the conditions. We tell you how long to leave it before we go.
Do you remove the old sealant?
Yes. Sealing over the old bead is the commonest cause of early failure, and it’s something we never do.
DIY sealant or a professional job?
A careful DIYer can reseal a simple joint, like a short, easy-to-reach joint indoors. Where it goes wrong is sealing over the old bead, working on a wet joint or overloading the gap.
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.
Nearby places to Lissenden Gardens
Also in Lissenden Gardens
How we quote for external mastic
There’s no set price list, because jobs vary so much. The quote depends on:
- How easy the joints are to reach
- Any working-time requirements on site
- How many areas need sealing
- The size of the job
Leaving a failed joint generally makes the job bigger, not smaller, because water and mould keep working on it. If you are unsure, ring 0345 464 0079 or drop us an email and we’ll give you an honest view and a quote.
Helping us quote
You don’t need to know the technical terms. It helps if you can tell us:
- Any access issues, like height or stairs
- If it’s domestic, commercial or a hotel
- What the problem is, such as mould, gaps, leaks or cracking
- The address or postcode of the job
The more we know about the job, the more useful the quote. Tell us where the job is, what’s wrong and how much there is, and add photos by email if you can.
What external mastic looks like in Lissenden Gardens
Historic houses like Keats House (about 0.8 miles west) are a reminder that the area around Lissenden Gardens 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. London terraces and converted houses often share gutters, downpipes and walls, so check who is responsible for the outside before booking.
Schools such as Parliament Hill School are buildings too, and movement joints, cladding joints and gutters on larger buildings need the same care as a house’s. For an older house near a landmark such as Highgate Road Chapel, an extension built onto an older house moves differently, and the joint between them takes the strain.
Lissenden Gardens is about 1 mile east of Hampstead, in Greater London. We provide external mastic to homes and businesses in Lissenden Gardens and nearby. Our Greater London coverage runs to 764 places, and Lissenden Gardens is one of them.
Every address in NW5, NW3 and N19 is covered for external mastic. Streets in the area include Rona Road, Dale Road and Fleet Road, and we cover them all. Neighbouring places we cover for external mastic include Gospel Oak (1 mile south), Dartmouth Park (1 mile north-east), Tufnell Park (1 mile east), Kentish Town (1 mile south) and Chalk Farm (1 mile south). Larger places within reach include London (5 miles south-east), City of Westminster (3 miles south), Marylebone (3 miles south), Kensington (5 miles south-west), St Pancras (3 miles south-east) and Shoreditch (4 miles south-east).
Local landmarks in Lissenden Gardens
In Lissenden Gardens, that means homes and buildings near Parliament Hill, The Royal School and Gospel Oak Primary School, among other places. Nearby too are The Bull and Last pub (less than half a mile north-east) and Cecil Sharp House (1.3 miles south). There’s a railway station in Lissenden Gardens itself: Gospel Oak station. Nearby you will also find Royal Northern Hospital (1.2 miles east) and Montfichet's Tower (3.7 miles south-east). Green spaces nearby include Parliament Hill and The Long Water.
Different surfaces, different methods
Brickwork movement joints
People sometimes point up a brick movement joint by mistake. Where one has been mortared, we cut it out and reseal it with sealant if the joint can be cleared.
Joints between dissimilar materials
Wherever two materials meet, they move differently. We seal the joint with a flexible exterior sealant so neither cracks the other.