Facade Sealing in St John's Wood
Facade joint and window perimeter sealing on commercial buildings in St John's Wood and across Greater London. CHAS accredited, Constructionline member, with a 12-month guarantee on workmanship.
- New sealant peeling off old mastic
- Gaps between rainscreen or cladding panels
- Hard, chalky sealant that no longer flexes
Need facade sealing in St John's Wood?
Share the site address and what’s failing, and we’ll reply with a fixed quote or arrange a visit.
How the job changes by surface
Render and coated surfaces
Rendered and painted facades need a sound edge for the sealant to bond to. We remove flaking material so the bead bonds to a firm surface, and areas needing repair are flagged.
Window and door perimeters
Window and door perimeters make up most facade sealing work. A low-modulus neutral-cure product, chosen for the frame and wall, goes in.
About our facade sealing in St John's Wood
Every facade quote starts with how the joints will be reached. Let us know what access exists or is planned, and any site rules we need to work around, so the price covers the real job. If you’re dealing with new sealant peeling off old mastic and discoloured or dirty facade joints, we can put it right, on window and door perimeters, shopfront frames and coping and flashing joints alike. Sealant applicators who only do sealant are a different proposition from a general trade with a gun in the van: on jobs in St John's Wood, preparation and product choice get the time they need.
Construction in a London area such as St John's Wood means working on constrained sites: small compounds, delivery slots and shared hoists and scaffold. Mastic is typically one of the last trades on each elevation or floor, so we keep to the programme and the order of trades the site sets.
What our 12-month guarantee covers is the way we did the job: the preparation, the sealing and the tooling. Damage, later alterations by others and movement beyond what the joint was designed for sit outside it.
- Place
- St John's Wood (NW8, NW6, NW3)
- Region
- Greater London
- Guarantee
- 12 months on every job
- Quote
- A fixed quote before we start
- Phone
- 01277 525 020
- Last updated
- 3 November 2026
Places near St John's Wood
Other services in St John's Wood
Common questions from St John's Wood clients
Is hospital work, at somewhere like Hospital of St John and St Elizabeth, something you do?
Yes. We work in healthcare settings as well as offices and schools. The estates team’s permit system and infection-control rules come first, and the work is planned around them.
Can you cope with the access rules in a London building?
Yes, most London buildings have access rules of some kind, and we plan around them. Share the building’s contractor rules and we’ll work to them.
Who decides which product is used?
Where there’s a specification, we use the product it names. If not, we choose for the movement, the surfaces and the conditions, in line with the manufacturer’s guidance.
Do you install glazing systems?
No. Glazing, windows and glass replacement aren’t part of our work. We seal the joints around them, such as perimeter joints where frames meet the structure.
How long before the joints can be used?
The product and site conditions decide that. Some take light use quickly, others need longer to cure, so we will confirm the curing time on the day.
Is any job too small?
We quote for single jobs as well as large packages and programmes. Send details for a fixed quote.
Do you use silicone for external joints?
The product follows the joint’s movement, the surfaces and the specification. Specifications often refer to BS EN 15651-1 for facade sealants or BS EN 15651-2 for glazing, and we work to what is specified.
When it isn’t the sealant
Honesty saves time and money. New sealant won’t cure:
- Movement beyond what any sealant can handle
- Specialist high-level access methods
- Damaged frames that need replacing
If in doubt, call the office on 01277 525 020 or email drawings and photos and we will say what we think.
Joints and surfaces we work on
- Coping and flashing joints
- Perimeter joints where frames meet the structure
- Cladding panel joints
- Shopfront frames
- Stone and brick facade joints
- Window and door perimeters
Keeping the joints sound
For the best life from the joints:
- Keep pressure washers away from fresh sealant
- Combine resealing with other works that need access
- Add perimeter sealant to planned maintenance checks
- Never let anyone seal over old sealant
Look at perimeter and panel joints as part of routine building checks. Signs to look for are cracking, edges lifting, chalking and stiffness; record the locations.
Building facade joints into a maintenance cycle avoids emergency repairs. Regular checks let you renew joints before water gets in instead of after the damage.
Owners, agents and contractors
Agents, factors and owners’ representatives all follow the same route: send the details, accept a fixed quote, and we carry out and guarantee the work. Keys, access and contacts can be agreed in advance.
Planned maintenance programmes are welcome: resealing failed joints building by building, on a schedule that suits your budget. Sites in St John's Wood can sit alongside others in a wider programme.
What happens if it’s left?
If access is already up for other work, resealing at the same time makes sense. Coordinating facade sealing with other external works avoids paying for access twice. Access in London is hard enough to arrange once, so it makes sense to deal with every failing joint while access is in place.
The work involved drives the cost: removing old material, preparing the joints, the product, the access and how the work is phased. Call for a fixed quote and we will explain how it’s made up.
Why clients in St John's Wood choose us
- 12 months’ guarantee on every job
- Health and safety: CHAS accredited
- Colours confirmed for the specified product
- Our applicators hold CSCS cards
Building and refurbishing in St John's Wood
A good number of hotels sit less than 2 miles from St John's Wood. Hotel schemes tend to have fixed reopening dates, so the mastic is programmed tightly with the other trades. As part of Greater London, St John's Wood is inside the ULEZ, which applies to every van on site. Add booked deliveries and tight storage, and the mastic package needs planning with the site team.
When units on a site such as The Quadrant Business Centre (1.4 miles west of St John's Wood) are refurbished or reclad, the panel joints and window perimeters are part of the mastic package. For contractors at a college like City of Westminster College, which lies south-west of St John's Wood, perimeters and internal sealant are timed for the holidays. For a contractor at a hotel such as St John's Wood Boutique Hotel, under half a mile east of St John's Wood, the mastic often has to be finished before a reopening date.
St John's Wood is about 1 mile south of Hampstead, in Greater London. Looking for facade sealing in St John's Wood? We can help, as we do across Greater London. Across Greater London, 764 places are covered, St John's Wood among them.
Anyone looking for facade sealing in NW8, NW6 and NW3 gets the same process as the rest of our area: send details, get a quote, we seal, guaranteed. For a building on The Lane, Hall Road and Hill Road or nearby, send details and we will quote for facade joints. Access to St John's Wood is via the A5205. Sites close to St John's Wood are covered too, including South Hampstead (1 mile north), Swiss Cottage (1 mile north), Primrose Hill (1 mile north-east), Lisson Grove (1 mile south) and Haverstock (1 mile north-east). Further afield, our area takes in London (4 miles south-east), Kensington (3 miles south-west), St Pancras (3 miles east), Shoreditch (4 miles east), Walthamstow (7 miles north-east) and Hoxton (4 miles east).
Local landmarks in St John's Wood
Locally, jobs take us to sites close to Cecil Sharp House, Primrose Hill and Arnold House School, among other places. You will also find Quintin Kynaston Community Academy (less than half a mile north-west) and Cafe Med pub (under half a mile north-west). St John's Wood has its own railway station: South Hampstead station. Well-known places in the area include Hospital of St John and St Elizabeth (less than half a mile south) and Montfichet's Tower (3.5 miles south-east). Open spaces near St John's Wood include The Long Water and Primrose Hill.
Our process
Our CSCS-carded applicators arrive with the sealants, primers and backing rod the job calls for. Joint faces are cleaned back to sound, dry surfaces, the manufacturer’s primer is applied where it’s called for, and each bead is tooled to a neat concave finish. In St John's Wood, most buildings stay in use during the work, so we agree zones and timings with the building or facilities manager. Phased work keeps the rest of the building in use.
- We start with photographs, drawings or a visit to see the joints and agree access.
- Product choice follows the joint’s movement and substrate.
- The existing bead comes out in full and both faces cleaned back.
- Primer is applied where the maker specifies it.
- Backing rod is fitted and the new sealant gunned in and tooled.
- The finished joints are checked with you.
Preparing the site
- Tell staff and tenants when we’ll be in
- Send your site hours and access windows
- Explain the parking and delivery arrangements
Request a quote
Send details, get a quote, we seal, guaranteed: that’s how every job runs. To take the first step, call the office on 01277 525 020 or send photos by email.