Greater London · England
Upper Norwood External Mastic
Sealing brickwork movement joints, render, cladding and façade joints for Upper Norwood, backed by a one-year guarantee. Call for a quick quote.
- Gaps where render, brick and frames meet
- Sealant that has lost its bond to the brick or render
- Joints with sealant missing in places
External mastic in Upper Norwood
Many failed façade joints only get noticed once there’s a stain or a damp patch inside. We inspect them, agree which need doing and reseal with a weatherproof, flexible sealant. Typical jobs include movement joints with cracked, split or missing sealant and rain getting behind render or cladding at a joint, on render & cladding joints, joints between brick and frames and façade panels.
Newer London blocks are built with movement joints in brick and render, and with cladding joints sealed with mastic. Older terraces have their own weak points: gutter joints, roofline trims and the joint where an extension meets the original wall, and both kinds of building are found across London.
We guarantee the work for a year. If there’s a problem with our work within the year, let us know and we’ll sort it.
- Where
- Upper Norwood (SE19, SE27, SE21)
- Wider area
- Greater London
- Guarantee
- 12 months on all our work
- Price
- Quoted before any work starts
- Phone
- 0345 464 0079
- Last updated
- 26 October 2026
Landlord and commercial work in Upper Norwood
From a single let to a portfolio, the work is the same standard: the old material taken out, careful preparation and a 12-month guarantee.
Housing providers, facilities teams and property managers book us too in Upper Norwood and across Greater London. We can quote a run of properties together, and we’re fully insured for the work.
Quotes for external mastic in Upper Norwood
For a quick quote, just ask. The main things that affect it are:
- Whether old sealant or filler has to be cut out
- Working hours on commercial sites
- How many areas need sealing
- Whether the work is at height
The cost depends on the amount of work, how hard the old material is to remove and how easy the joints are to reach. You’ll have a clear quote before any work starts, so you know where you stand.
Asking for a quote
When you contact us, these details help:
- If it’s domestic, commercial or a hotel
- What’s wrong with the joints now
- Whether it has been sealed before
- The rough size of the job
Every job is quoted individually, so the first step is telling us about yours. Just call 0345 464 0079 or drop us an email with the details, and pictures are welcome.
Do you need external mastic in Upper Norwood?
Buildings move more than people expect. Clay bricks expand slightly over their life, concrete and block shrink, and everything moves with temperature and wet. All of that ends up in the joint sealant.
If you can see any of these, it’s time to have the joints looked at:
- Sealant pulling away from one side of the joint
- Failed seals between different materials
- Rain getting behind render or cladding at a joint
- Plants rooting in failed movement joints
Upper Norwood is in London, so parking needs planning: let us know about parking bays, permits or a driveway.
Before you book anyone
- What guarantee comes with the work
- Whether they’re fully insured
- Is the old sealant removed completely?
- What product goes in the joint
What external mastic looks like in Upper Norwood
In terraces and conversions, gutters and walls are often shared with the neighbours, so check who is responsible for the outside before booking. Rainfall in the South East is lower than in much of the UK, but outside sealant still needs a dry, clean surface, so outdoor work is planned around the forecast.
In the older streets around Christ Church, old and new materials meet at the roofline and walls, which is where sealant earns its keep. Rented homes near Gipsy Hill station change hands often, and outside joints that have cracked can let damp into a rental, so check them between lets.
Upper Norwood is about 4 miles south-east of Stockwell, in Greater London. Whether you’re in the middle of Upper Norwood or further out, external mastic is available for homes and businesses alike. Across Greater London, we cover 764 places, Upper Norwood among them. We also work in London, around 6 miles away.
Our applicators cover all of SE19, SE27 and SE21 for external mastic. External mastic is available to properties on Dover Road, Hawke Road and Tudor Road. Being close to the A214, Upper Norwood is simple for us to get to. We also cover the places around Upper Norwood: Norwood New Town (1 mile west), Gipsy Hill (1 mile north-east), West Norwood (1 mile north-west), Crystal Palace (1 mile east) and Anerley (1 mile east). We also work in nearby towns such as London (6 miles north), City of Westminster (7 miles north-west), Marylebone (7 miles north), Kensington (7 miles north-west), St Pancras (7 miles north) and Shoreditch (7 miles north).
Around Upper Norwood
In Upper Norwood, that means homes and buildings near The Sparrowhawk pub, Long Meadow and Rockmount Primary School, among other places. There’s a railway station in Upper Norwood itself: Gipsy Hill station. A little further out are St Christopher's Hospice (1.3 miles east) and Crystal Palace Museum (0.5 miles east). The countryside around Upper Norwood includes Dulwich Upper Wood and Knight's Hill.
What happens if it’s left?
Water gets in through a failed movement joint and can run behind render or cladding. Dealing with it early keeps the repair to the joint, instead of the wall and finishes around it. 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.
Rather than a set price list, we look at what your job involves: how many joints, what’s in them now and how we reach them. The price is agreed before we begin.
Why Upper Norwood customers choose us
- Domestic, commercial and hotel work
- Fully insured
- We never seal over old sealant
- More than 20 years in sealant work
Nearby places to Upper Norwood
Other services in Upper Norwood
Can I do it myself?
Some jobs are best left to a professional: high-level joints, fire-rated gaps, external movement joints and big jobs need the right product, the right access and the right method.
If you’ve already had a go yourself, that’s fine. We cut it out and start again, so just mention it when you contact us.
FAQs for Upper Norwood
Do you work for landlords with property near Gipsy Hill station?
Yes, we work for landlords and letting agents. Just phone 0345 464 0079 or email us and tell us about the property, and we’ll send you a clear quote.
Do you cover Upper Norwood for external mastic?
Yes. Our work covers London and the South East, and Upper Norwood is part of that. Just ring 0345 464 0079 or drop us an email with a few details of the job.
Do you take out the old sealant first?
Yes, always, and completely. New silicone does not stick to old silicone, so the joint is cleaned back first.
Is it OK to seal over old sealant?
No. New silicone won’t bond to old silicone, and anything trapped underneath, including mould and water, stays there. We remove it all first.
When will the joints need doing again?
It varies from wall to wall: sunny, exposed elevations and busy joints wear faster. Check them each year and reseal when they split or harden. Every job carries our 12-month guarantee.
Is it OK to fill a movement joint with cement?
No. Mortar locks the joint solid, so the wall cracks somewhere else instead. Use a flexible sealant with backing rod.
Do you hold any approvals?
Yes. ARBOMaster is the approved applicator scheme for Arbo sealants, and we’re part of it.
Do the sealants smell?
Some sealants have a smell while they cure, but it fades. Ventilation helps.
The process
Once we are on site, we check the joints match what you told us. If we find something unexpected, we talk it through with you first. After that, the work takes a few hours to a few days, depending on the length of joint and the access. For a job in Upper Norwood, 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.
- Each joint is checked and the colour of the new sealant agreed.
- We take out the old sealant until the faces are sound.
- Backing rod goes in so the sealant can stretch between the two faces.
- We prime the faces where required.
- We gun in low-modulus sealant and tool it neatly.
Before we arrive
- Clear items away from the joints we’re working on
- Try not to wet indoor joints just before the visit
- Mention any parking rules near the property
Get a quote
A good description makes for an accurate quote. Let us know the location, the problem and roughly how many joints, and add photos by email if you can.
Read more
How to look after the new joints
Looking after new joints is easy:
- Leave the joints unpainted unless we have said otherwise
- Walk round the building once a year and look at the joints
- Avoid pressure-washing directly into sealant joints
- Tell anyone working on the walls about the movement joints
Keep the joints clear of soil, plants and climbing growth. Anything that holds water against the joint wears it out sooner.
Small splits are the time to act. At that stage it’s a simple cut out and reseal before water has had years to get in.