Greater London · England
External & façade joints in Lower Morden, Greater London
External mastic across Lower Morden and nearby, with every bit of old sealant taken out first and a 12-month guarantee.
- Gaps where render, brick and frames meet
- Failed sealant between panels on a façade
- Sealant pulling away from one side of the joint
What happens on the day
On the day, there’s very little for you to do. Show us the job and we’ll take it from there. The job generally takes anything from a few hours to several days, depending on the building from start to finish. For a job in Lower Morden, parking and access are the things to plan: let us know about parking, the floor we will be working on and any lift or shared entrance.
- We start by checking each joint, agreeing the ones to redo and how we will reach them.
- Old sealant and any debris are cut and raked out.
- We clean both faces of the joint and prime them where the product calls for it.
- Closed-cell backing rod is fitted to set the depth and stop three-sided bonding.
- The new sealant, chosen to suit the brick or render, is applied and tooled to a neat finish.
How to prepare
- Let us know if you’ve seen damp or leaks
- On commercial sites, let us know about site rules
- For indoor joints, keep the area dry beforehand if you can
Ask for a quote
For a quote, call 0345 464 0079 or drop us an email with the location and a short description of the problem. You’ll have a clear quote before any work starts.
Advice
External mastic in Lower Morden
Joints in render and cladding are easy to overlook until a damp patch appears. We inspect them, agree which need doing and reseal with a weatherproof, flexible sealant in a colour to suit. We work on render & cladding joints, façade panels and copings & trims, and common reasons people get in touch are moss and dirt in joints with no sealant left and gaps where render, brick and frames meet.
In London terraces and converted houses, gutters and walls are often shared with the house next door, so a leaking gutter joint or failed wall joint can affect more than one home. For a flat in Lower Morden, check the lease for who looks after the outside.
A one-year guarantee comes with the work, just as it does everywhere we cover.
- Location
- Lower Morden (SM4, SM3, KT4)
- Wider area
- Greater London
- Cover
- 12 months on all our work
- Price
- A clear quote up front
- Phone
- 0345 464 0079
- Last updated
- 26 October 2026
DIY versus a professional finish
Not every job suits DIY: work at height, external movement joints, fire-rated sealant and large areas call for the right materials, safe access and experience.
If you’re set on DIY, put the effort into preparation: remove every trace of old sealant, clean and dry the joint, and follow the product’s cure time. If it fails, we can still redo it.
Landlords, agents and businesses in Lower Morden
We work for landlords and letting agents as well as householders. Sealant work between tenants keeps a property looking cared for before the next move-in.
We also work for businesses, from offices to washrooms and kitchens. For commercial premises, we can talk through working times when we quote.
Places near Lower Morden
More services for Lower Morden
Keeping the joints in good condition
Once the sealant has cured, a few habits help it last:
- Have failed joints looked at early
- Walk round the building once a year and look at the joints
- Tell anyone working on the walls about the movement joints
- Don’t let climbing plants root in the sealant
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.
Leave it or put it right?
Low-modulus sealants stretch easily, so they put less strain on the joint edges. That matters on brick, render and concrete, which can be weaker at the face. A stiffer product can damage the joint edge as it fails. In a flat in Lower Morden, failed sealant seldom stays inside your own four walls: water from a shower or window joint can reach the flat below, and gaps in fire-stopping matter to everyone in the building.
What you pay reflects the work, not a rough estimate. That is why we ask about the job first.
What you get with us
- Domestic, commercial and hotel work
- One-year guarantee on every job
- Any old sealant cut out fully, not covered over
- Arbo and Everbuild products
Read our cost guide and our reviews.
Do you need external mastic in Lower Morden?
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.
The most common problems we see are:
- Moss and dirt in joints with no sealant left
- Hard, crazed mastic that has stopped moving
- Movement joints with cracked, split or missing sealant
- Failed sealant between panels on a façade
For an older house near a landmark such as St Martin's, older walls, gutters and the joints where extensions meet them need a flexible sealant.
Before booking anyone
- When the joint can take water or movement
- What insurance they hold
- How much experience the applicator has
- What guarantee comes with the work
Lower Morden buildings and the weather
With historic houses such as Southside House (about 2 miles north) nearby, there’s older building stock in the area around Lower Morden as well as newer homes. Where a home is older, 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.
As a London address, Lower Morden can be tricky for parking: tell us about permits, visitor bays or off-street space when you book. Managing a site like Aragon Primary School? Then larger buildings have long runs of movement joint that eventually need resealing.
Lower Morden is about 2 miles north-west of Sutton, in Greater London. For external mastic in and around Lower Morden, it’s easy to get a quote: please ring 0345 464 0079 or send us an email. We cover Greater London from our Crawley base, Lower Morden included. Our Greater London coverage runs to 764 places, and Lower Morden is one of them. For nearby work, see our London page (9 miles or so).
Our applicators cover all of SM4, SM3 and KT4 for external mastic. Whether your property is on Ash Road, Bow Lane and Garth Road or a nearby road, we can help. We also cover Morden (1 mile north-east), Sutton Common (1 mile east), North Cheam (1 mile south), Worcester Park (2 miles south-west) and Stoneleigh (2 miles south-west). Larger places within reach include London (9 miles north-east), City of Westminster (9 miles north), Marylebone (9 miles north), Kensington (8 miles north), St Pancras (10 miles north-east) and Shoreditch (11 miles north-east).
Local landmarks in Lower Morden
Typical jobs here are in homes near Cannon Hill Common, Lord Nelson pub and Merton College, among other places. The nearest railway station is St Helier station, about 0.9 miles east. Other landmarks nearby include St. Anthony's Hospital (0.6 miles south) and Cockney Museum (2.1 miles south-west). For a walk, there’s Derwent Floodwash and Henman Hill.
Your questions about external mastic in Lower Morden
I let a flat near St Helier station. Can you help?
Yes, landlords and agents are among the people we work for, and several properties can be quoted together. You can call 0345 464 0079 or send us an email with the details for a clear quote.
Is parking a problem for a job in Lower Morden?
London parking needs a little planning, so let us know about permits, bays or a driveway when you book. That way the visit can be planned around it.
Can you reach joints on upper floors?
That depends on how high the joints are and the ground below. Low-level joints are straightforward; for higher work, tell us about the building and we will confirm what’s needed.
Do you remove the old sealant?
Yes. We cut out all the old sealant and clean the joint before resealing.
Can you do several jobs on one visit?
Yes. More than one area can be quoted together.
Why is there a gap in my brick wall?
It’s a deliberate gap that lets the wall expand and contract without cracking. It should be filled with flexible sealant, never mortar.
What sealant do you use?
Each joint gets the product that suits it. Movement, water and weather all affect the choice, and we will tell you what we’re using.
How often do external joints need resealing?
There’s no fixed answer: sunny, exposed elevations and busy joints wear faster. Check them each year and reseal when they split or harden. Our work comes with a 12-month guarantee.
Quotes for external mastic in Lower Morden
Your quote is based on your job. We look at:
- How many areas need sealing
- Whether old sealant or filler has to be cut out
- Any working-time requirements on site
- Whether there’s mould to deal with
What it costs depends on the amount of work, how much old material has to come out and access to the work. We give a clear quote before work begins.
What we need to know
Photos help, but a description is a good start. Please mention:
- Whether it’s a home or a business
- Photos by email, if that’s easy
- The rough size of the job
- If someone has resealed it before
We do not publish a price list. Instead, we give you a clear quote for your job. To arrange one, ring 0345 464 0079 or email us.