Greater London · England
Cannon Hill Gutter Sealing
Gutter sealing for Cannon Hill, by sealant specialists with 20+ years’ experience. Rated 4.9 on Google from 180+ five-star reviews.
- Damp on an inside wall under a dripping gutter
- Dripping gutter ends
- Open joints in fascias and soffits
Cannon Hill 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 Southside House (about 1.2 miles north-west) are a reminder that the area around Cannon Hill has older buildings as well as new. In older buildings, older walls and rooflines need a sealant that moves with them and suits the material.
Cannon Hill is in London, so parking needs planning: tell us about permits, visitor bays or off-street space when you book. Homes close to St James Merton include some older properties, and old and new materials meet at the roofline and walls, which is where sealant earns its keep. Rented homes near South Merton station change hands often, and leaking gutter joints on a rental are best caught before they stain the walls.
Cannon Hill is about 1 mile north-west of Morden, in Greater London. Whether you are in the middle of Cannon Hill or further out, we cover gutter sealing for every kind of property, from flats and houses to offices and hotels. Cannon Hill is one of 764 towns and villages in Greater London where we work. We also work in London, about 9 miles from Cannon Hill.
Jobs for gutter sealing in SW20, SM4 and KT3 works the same way as everywhere else we cover. We cover properties on Aylward Road, Camborne Road and Botsford Road and the roads around them. Close by, we work in Bushey Mead (1 mile north-west), Raynes Park (1 mile west), Wimbledon Chase (1 mile north), West Barnes (1 mile west) and Merton Park (1 mile north-east). Within a short drive, we also cover London (9 miles north-east), City of Westminster (8 miles north), Marylebone (9 miles north), Kensington (7 miles north), St Pancras (10 miles north-east) and Shoreditch (11 miles north-east).
What’s near Cannon Hill
Typical jobs here are in homes near The Edward Rayne pub, Cannon Hill Common and Harris Academy Wimbledon, among other places. Cannon Hill’s nearest station is South Merton station, roughly 0.5 miles north-east. Well-known places in the area include St. Anthony's Hospital (1.5 miles south) and Wimbledon Museum (1.6 miles north). Open spaces near Cannon Hill include Cherry Wood and Henman Hill.
About our gutter sealing in Cannon Hill
Many dripping gutters are just a failed joint or end cap. The joint is cleaned, dried and resealed using a gutter sealant. If the gutter is broken or sagging, we will tell you. We work on garage door frames, gutter end caps and soffit joints, and common reasons people get in touch are quick sealant fixes on gutters that didn’t last and damp patches inside below a leaking gutter.
Modern London flats rely on sealed movement joints and cladding joints. Period houses have different weak points, such as gutter joints, trims and the line where an extension meets the old wall.
We stand behind the work with a 12-month guarantee, so you’re covered after we have gone.
- Place
- Cannon Hill (SW20, SM4, KT3)
- Wider area
- Greater London
- Guarantee
- A year, on every job
- Quote
- A clear price before any work starts
- Phone
- 0345 464 0079
- Updated
- 26 October 2026
How the job changes by surface
Gutter joints
When a joint drips, the gutter is often still sound. Sealing the joint often stops it.
uPVC fascias
Open fascia joints look untidy and can let water in. Sealing them closes the gap.
How the visit works
Good joint work is mostly preparation, and we do not rush it. Joints are cleaned back and dried before anything new goes in. In total, it generally takes anything from an hour or two to a few hours. In Cannon Hill, 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 look at the gutters, fascias and trims and agree the joints to seal.
- We clean out each joint.
- We make sure everything is dry.
- The sealant is applied and finished.
- We check our work before we leave.
How to prepare
- Mention any sign-in or site rules at work premises
- Let us know about stairs, lifts or work at height
- Tell us about any previous sealing or DIY attempts
Getting a quote
A good description makes for an accurate quote. Let us know the location, the problem and roughly how many joints, and email pictures if that is easy.
Read more
Nearby places to Cannon Hill
What else we do in Cannon Hill
Aftercare tips
Once the sealant has cured, a few habits help it last:
- Get a dropping gutter looked at quickly
- Check that water runs out of the downpipes
- Rest ladders on the wall, not the gutter
- Sort out a dripping joint early
Leave the new sealant to cure as we advise and avoid disturbing it.
A leaking stop end is best sealed before the wet months. A winter of drips can lead to damp patches.
Why act early in Cannon Hill
Replacing guttering is a much bigger job than sealing joints. Where the gutter is in good order and only a joint leaks a reseal is all it needs. If it has failed, we will tell you. In a London flat, a failed joint rarely stays your problem alone: water from a shower or window joint can reach the flat below, and gaps in fire-stopping matter to everyone in the building.
Doing several joints on one visit is normally more efficient than separate visits, so it’s worth mentioning everything you’d like done. We’ll give you a clear price for the lot.
Why choose Mr Mastic in Cannon Hill
- Sanitary silicone with an anti-fungal additive in wet areas
- White, clear, grey or another colour, product permitting
- 12-month guarantee on every job
- Arbo and Everbuild products
See our cost guide and our reviews.
Quotes for gutter sealing in Cannon Hill
We quote each job individually. These are the things that affect it:
- The product the joint needs
- The old material and how stubborn it is
- Any mould that needs treating
- Any working-time requirements on site
The cost reflects the work involved, not guesswork. That’s why we ask about the job first and give you a clear quote before work begins.
What to tell us for a quote
You don’t need to know the technical terms. It helps if you can tell us:
- If it’s domestic, commercial or a hotel
- How we’d reach the joints
- What the problem is, such as mould, gaps, leaks or cracking
- If someone has resealed it before
We don’t publish a price list. Instead, we give you a clear price for your job. To arrange one, call 0345 464 0079 or drop us an email.
Cannon Hill: your questions answered
Can you do gutter sealing in Cannon Hill?
Yes, Cannon Hill is within the area we cover. We work across London and the South East. Just call 0345 464 0079 or send us an email with a few details of the job, and we’ll send you a clear quote.
I let a flat near South Merton station. Can you help?
Yes, we work for landlords and letting agents. You can call 0345 464 0079 or email us with the address and a few details, and we will give you a fixed price before any work starts.
Will you clear out my gutters?
We clean the joints we’re sealing and any debris nearby is cleared. Cleaning the whole run is a different job.
Is sealing fascia joints something you do?
We do. We seal the joints, not replace the boards, and if a board is damaged, we’ll tell you.
Will there be a smell?
That depends on the sealant. Some smell for a while, some hardly at all.
Can you fit new guttering?
No. We seal joints and replacement is a job for an installer.
Can a leaking gutter joint be sealed?
In most cases, yes. If the gutter is sagging or cracked, sealing won’t last and we will say so.
Is it messy?
Very little: the area around the joints is protected first, and we tidy up before we go.
DIY sealant or a professional job?
Sealing over old silicone is the commonest DIY error. New silicone won’t bond to old, so it peels away and traps moisture behind it. All the old material has to come out first.
Too much sealant is as bad as too little. A thick, smeared bead looks untidy and doesn’t move well, and the joint depth matters as much as the finish.
What we cannot put right
Before booking, it’s worth knowing the limits:
- Leaks from the roof rather than a joint
- A gutter length that has split
- Sagging gutters or broken brackets
If you’re not sure, just ring 0345 464 0079 or send us an email and we’ll give you a straight answer.
Surfaces we seal
- uPVC fascias
- Roofline trims
- Soffit joints
- Gutter end caps
- Garage door frames
- Gutter joints