West Dulwich mastic sealing
Need mastic sealing in West Dulwich? Send us the details for a fixed quote, backed by a 12-month guarantee on the work.
- Repeated reactive repairs to the same buildings
- Leaks at window and door perimeters
- Occupiers reporting cold air round windows
Mastic sealing for businesses in West Dulwich
Photos, a specification or a quick description of the joints is enough to start a fixed quote.
How we handle mastic sealing in West Dulwich
Different joints need different sealants. Low-modulus neutral-cure silicone suits many window perimeters and external movement joints, and MS polymer sealants stick well to many substrates and often take paint, and colours are confirmed for whichever product is used. Most enquiries involve water getting in round frames after rain and open joints in brickwork or panels, on shopfronts below residential blocks, window and door perimeters on blocks and external wall and movement joints. Whoever orders the work in West Dulwich, the brief is usually the same: a clear scope, tidy work and joints that don’t fail again.
In a London area such as West Dulwich, many buildings are blocks of flats or mixed-use buildings run by managing agents, landlords or housing associations. Window and door perimeters, balcony joints and communal areas all have mastic that ages together across a building.
The 12-month guarantee covers our workmanship: the preparation, the sealing and the tooling. Damage, later alterations by others and movement beyond what the joint was designed for sit outside it.
- Where
- West Dulwich (SE21, SE27, SE19)
- Region
- Greater London
- Cover
- A 12-month guarantee
- Quotes
- A fixed quote before we start
- Phone
- 01277 525 020
- Page updated
- 3 November 2026
Looking after buildings in and around West Dulwich
West Dulwich has four care or nursing homes no more than 2 miles away. For owners and operators of care buildings, window perimeters and external joints are best renewed in planned phases around residents. For a London block, the agent or landlord normally handles notices to residents and access to flats. We fit the programme to your notice periods.
For a school such as Dulwich Wood Primary School, perimeter mastic on windows and doors is a holiday job. Property owners at sites such as Hamilton Road Industrial Estate, under half a mile south-west of West Dulwich, can have mastic renewed between lettings.
West Dulwich is about 1 mile north-east of West Norwood, in Greater London. If you’re looking for mastic sealing in West Dulwich, we can help. Across Greater London, 764 places are covered, including West Dulwich.
We cover the SE21, SE27 and SE19 postcode districts. We cover commercial and managed buildings on Berry Lane, Clive Road and Myton Road. Being close to the A2199, West Dulwich is straightforward for us to reach. If your building is just outside West Dulwich, we cover Sydenham Hill (1 mile east), West Norwood (1 mile south-west), Gipsy Hill (1 mile south), Dulwich (1 mile north) and Upper Norwood (1 mile south). Bigger towns within reach include London (5 miles north), City of Westminster (6 miles north-west), Marylebone (6 miles north-west), Kensington (7 miles north-west), St Pancras (7 miles north) and Shoreditch (6 miles north).
Near you in West Dulwich
Recent enquiries here include premises near The Wood House, Dulwich Prep & Senior and Kingsdale Foundation School. There’s a railway station in West Dulwich itself: Sydenham Hill station. Nearby you will also find British Vintage Wireless And Television Museum (less than half a mile west) and St Christopher's Hospice (1.3 miles south-east). For a walk, there’s Battersea Park Lake and Dulwich Upper Wood.
Should maintenance staff do it?
Using site staff can make sense for a small touch-up, but anything bigger is another matter: a specialist works through quantities efficiently, leaves a consistent finish and backs it with a 12-month guarantee.
Certain joints really need a specialist: fire-rated seals that must follow a tested detail, trafficked floor joints and external movement joints among them. Getting these wrong typically costs more in the end than doing them right.
Towns and villages near West Dulwich
More services for West Dulwich
Diagnose, treat, sign off
A typical day starts with protection: masking tape along the joint edges and sheeting over anything nearby. On site, the work typically takes one or more days per building, depending on the joint lengths and the access, and we clear our waste as we work. All of Greater London is in the ULEZ, and kerbside space in West Dulwich can be scarce. If there’s a loading bay, a car park or a permit we can use, tell us when you send details.
- First comes a look at the joints and, for older buildings, the asbestos records.
- A fixed quote covers the joints, products and order of work.
- We strip out the old sealant.
- The joints are prepared and resealed with the right product.
- Buildings are completed in turn.
Preparing the site
- Point out parking and an unloading spot
- Confirm the product named in the specification
- Let us know about inductions and permits
Request a quote
If there’s a specification, drawings or a tender package, send it with your enquiry, and we’ll price against exactly what is specified. For smaller jobs, photographs and a description will do.
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When to call us in West Dulwich
Occasionally the substrate fails, not the sealant for example where render or brick edges crumble. If the edges are unsound, we say so before quoting the sealing.
If one of these sounds familiar, it’s time for a closer look:
- Damp patches beside frames
- Damaged joints in communal entrances and corridors
- Movement joints with sealant missing
- The same joint failures repeated across a portfolio
If you’re responsible for a building such as Church of St Stephen, frame and door mastic needs the same attention as any other property.
Questions to ask before you book
- Their public liability cover
- How the joint faces will be prepared and primed
- How they’ll work around occupants
- Which product they’ll use, and why it suits the joint
After the work
For the best life from the joints:
- Mention RAMS, insurance or CSCS requirements up front
- Check the asbestos register before any old mastic is disturbed
- Make it easy for occupiers to report draughts
- Reduce knocks to communal area joints
Where a paintable product was specified, it can be painted after curing. Silicone normally can’t be painted, so keep decorators off it.
Left open, joint edges in render, brick or frames can deteriorate. Then the edges may need repairing first and the job grows.
Your questions answered
Can you work in a London building with booked loading and goods-lift slots?
Yes, we plan every London job around the building’s own access rules. Share the building’s contractor rules and we’ll work to them. We allow for the ULEZ, which covers every borough
Will you take on a block within reach of Sydenham Hill station?
Yes, and several blocks can go on one quote. Give us the building’s details and say how residents are notified, and we’ll quote and plan to suit.
How do you choose the sealant?
A specification, where there is one, decides it. If there isn’t one, it comes down to the joint: its movement, its surfaces and what it has to cope with.
Can you work to our specification?
Yes. Include it with the drawings when you ask for a quote, and the quote will be based on it, flagging anything that needs clarifying.
Is asbestos a concern with old mastic?
Some mastics in pre-2000 buildings contain asbestos. We check the asbestos register or survey before disturbing it, and if it’s suspected, work stops until it’s tested.
Does the weather affect the work?
Outside, yes. The joint has to be dry and within the product’s temperature range, so damp, frosty or very cold days can stop external work. Inside work is seldom held up.
What paperwork can you provide?
We’re CHAS accredited, a Constructionline member and carry public liability insurance. For specific documents, tell us what site paperwork you need (RAMS, insurance certificate, CSCS details) and we’ll confirm with the quote.
What happens if it’s left?
Reacting to every complaint means sending someone out block by block. Planned resealing covers a whole building or estate in one go, under a single quote and a single programme. In a London building, a failed joint rarely affects only one party: water travels through shared structures, and a small leak becomes a dispute between occupiers. Dealing with it early is simpler for everyone.
Access often affects the price as much as the sealing: joints within easy reach take less time than ones that need access equipment. Mention the access as part of your enquiry.
Why us?
- Colours confirmed for the specified product
- Joints cleaned back to sound surfaces
- One phone line for London, the South East and Scotland
- RAL and finish matching where the product range allows
See how commercial sealant jobs are priced and our accreditations.
What sealant work can’t fix
A proper diagnosis includes knowing what sealant can’t do. We will tell you if the real problem is one of these:
- Leaks from above rather than through a joint
- Broken glass or failed sealed units
- Frames that are rotten, warped or broken
If you are not sure, just call 01277 525 020 or email the details over and we’ll give you a straight answer.
What we seal
- Window and door perimeters on blocks
- Communal entrances and stairwells
- Shopfronts below residential blocks
- Communal kitchens and washrooms
- External wall and movement joints
- Balcony and threshold joints