Belgravia construction mastic
Construction mastic for Belgravia, from a contractor working since 2005. Fully insured, with a 12-month guarantee.
- Different trades sealing to different standards
- External joints sealed in damp or cold conditions that are now failing
- Missed perimeter joints on a new elevation
Need construction mastic in Belgravia?
Photos, a specification or a quick description of the joints is enough to start a fixed quote.
About our construction mastic in Belgravia
Most of the packages we price run well beyond frames: external door and window perimeters, internal decorators’ caulk where specified, sanitary joints in bathrooms and washrooms, kitchen worktops and splashbacks, and snagging before handover. One contractor for all of it keeps the responsibility in one place. We work on sanitary and kitchen joints, cladding and panel joints and floor and skirting junctions, and the usual reasons a site gets in touch are existing joints on a refurb that need cutting out and resealing and sealant knocked or painted over by other trades. A specialist sealant contractor works differently from a general builder: in Belgravia, that means joint design, primers and backing rod as standard.
Around Belgravia, as across London, much of the work is refurbishing existing buildings as well as building new ones. Replacement windows, recladding and fit-outs leave perimeter and facade joints to seal, often next to people still using the building.
A 12-month guarantee applies to all our work in Greater London. Should something we installed fail, call 01277 525 020 or email the details over and we’ll come back to it.
- Location
- Belgravia (SW3, SW1X, SW1W)
- Region
- Greater London
- Cover
- 12 months on our workmanship
- Quotes
- Fixed quote, scope in writing
- Phone
- 01277 525 020
- Updated
- 3 November 2026
Doing it in-house
For a quick touch-up, site staff may be fine, but anything bigger is another matter: a specialist brings efficiency, a consistent finish and a 12-month guarantee.
Redoing a failed joint normally costs more than getting it right at the outset, since all of it has to come out and the faces be cleaned back again. That’s why many clients bring in a specialist from the beginning.
Looking after the joints
After handover, these steps help:
- Ask installers to correct oversized gaps first
- Ask for joint and product checks before the package is urgent
- Ask cleaners to use soft cloths around fresh sealant
- Bring the mastic contractor in after the last trades are through
Our 12-month guarantee covers the workmanship from sign-off. The guarantee covers how we sealed, not later damage by other trades, so protecting sealed areas matters.
In wet areas, a weak sanitary joint shows up quickly once the building is occupied. Leaks behind showers and basins damage finishes and floors, leaving the remedial work to the contractor. Proper preparation, with the right silicone first time, keeps it off the defects list.
From enquiry to sign-off
We bring the products specified for the job, along with primers and backing rod. Any old material is cut back to clean, sound faces, the manufacturer’s primer is applied where it’s called for, and each bead is tooled to a neat concave finish. Planning a London job such as one in Belgravia starts with access: booked loading, goods lifts, the building’s permit system and a spot to keep materials. Give us the hours we can be on site and we’ll schedule to suit.
- We price from the drawings, specification and programme you send.
- A fixed quote sets out the scope, the products and the sequence.
- Any site paperwork you need (RAMS, insurance certificate, CSCS details) is confirmed with the quote.
- Areas are sealed plot by plot or floor by floor as the trades hand them over.
- Joints are cleaned, primed where the maker requires it, backed and sealed to the specification.
- Before handover, snags are dealt with and the package is signed off under our 12-month guarantee.
What we need from you
- Point out parking and an unloading spot
- Flag any permit to work we’ll need
- Send any specification or drawings in advance
Getting a fixed quote
We quote a fixed sum against the scope you give us, so the cost is agreed before work starts. To ask for one, speak to us on 01277 525 020 or email a schedule or drawings.
Advice
Belgravia: questions and answers
Can you work in a London building with booked loading and goods-lift slots?
Yes. Inductions, permits and timed loading are routine for us in London. Say when the building is occupied and when it’s quiet, and we will plan accordingly. The ULEZ covers the whole of Greater London, which we allow for
Can you work around term dates at a campus such as Faculty of Medicine (Imperial College London)?
Yes. Education sites typically want the work in vacations or in phases during term, and we plan to suit. We’re CHAS accredited and a Constructionline member, and paperwork such as RAMS is confirmed with the quote.
Will you quote for a small job?
We quote for single jobs as well as large packages and programmes. Send details for a fixed quote.
What hours do you work?
We’re in the office from 8am until 5pm, Monday to Friday. Let us know your site hours and access windows, and the work will be planned around them.
Will you just go over the old sealant?
No. Failed sealant is removed and the faces cleaned back to sound, dry material first, because fresh silicone will not bond with aged silicone.
Do you do fire-rated sealing on new builds?
Where it’s specified, yes. We’ll flag if the detail needs a different product.
Can you work plot by plot or floor by floor?
Working to your programme, we seal each area as it’s handed over. The sequence is agreed with the site manager at the start and updated as the programme moves.
Quoting for work in Belgravia
Your fixed quote is built from the real scope. It allows for:
- Travel to remote or island sites
- Site requirements such as inductions and permits
- Whether old sealant has to be cut out first
- The size and state of each joint
There’s no price list, because the scope varies so much from one building to the next. Call for a quote.
What we need to price the job
Whether it’s one area or a whole building, the same details help:
- Clear photographs of the problem areas
- The site address and postcode
- Your programme or deadline
- Anything awkward about access or site hours
If there’s a specification, drawings or a tender package, send it with your enquiry, and we will price against exactly what is specified. For smaller jobs, photographs and a description will do.
Facades, frames and programmes in Belgravia
A 2-mile radius around Belgravia takes in a good number of hotels. Hotel refurbishments often run to tight programmes between busy periods, and perimeter and sanitary sealant has to keep up. Every borough of Greater London is inside the ULEZ, and that applies to contractors’ vehicles on any job in Belgravia. London sites also mean booked deliveries and limited storage, which the mastic programme has to allow for.
New wings at hospitals like Lister Hospital (to the south of Belgravia) bring long runs of window and panel joints to seal. New units and refits on sites such as Brompton Cross District Shopping Centre., 0.6 miles south-west of Belgravia, need their panel and perimeter joints sealed to the specification.
Belgravia is about 1 mile south of City of Westminster, in Greater London. Across the SW3 postcode area, the process is the same: send details, get a fixed quote, we seal, and the work is guaranteed. Across Greater London, 764 places are covered, Belgravia among them.
Work on mastic packages is covered throughout SW3, SW1X and SW1W, for business premises of every kind. For a building on Hans Road, Eaton Lane and Gerald Road or nearby, we can quote for mastic packages. With the A3214 and A3217 nearby, Belgravia is straightforward for us to reach. Nearby places we also cover include Brompton (1 mile south-west), Victoria (1 mile south-east), Chelsea (1 mile south-west), Pimlico (1 mile south-east) and Westminster (1 mile east). Bigger towns within reach include London (3 miles east), St Pancras (3 miles north-east), Shoreditch (4 miles north-east), Walthamstow (8 miles north-east), Hoxton (4 miles north-east) and Whitechapel (4 miles east).
Local landmarks in Belgravia
Around Belgravia, our work takes us to commercial buildings near Saint Thomas More Language College, Green Park and Natural History Museum Library and Archives and the streets around them. Also close by are Star Tavern (less than half a mile north-west) and Inchbald School of Design (less than half a mile south). The nearest railway station is London Victoria station, about 0.5 miles south-east. A little further out are Health Exhibition Centre (less than half a mile south-east) and Harrods (under half a mile west). The countryside around Belgravia includes Campden Hill and Serpentine.
Nearby places to Belgravia
What else we do in Belgravia
How the job changes by surface
Window and door perimeters
Gaps around frames have to be within the sealant’s range. Gaps outside the product’s range are raised with the site team before sealing starts.
Bathrooms, en suites and washrooms
In bathrooms and washrooms, an anti-mould sanitary silicone goes around every fitting. Each joint is prepared, sealed and finished with a neat tooled line.
Common problems we fix in Belgravia
Shrinkage and settlement in the first months put new joints under strain. Materials lose construction moisture and shrink, which opens up internal joints, particularly where caulk has been used in a joint that moves. Picking a flexible sealant where there’s movement keeps snags down.
Things that typically lead to an enquiry:
- Internal caulk splitting as the building dries out
- Snag items on joints that need redoing before handover
- Existing joints on a refurb that need cutting out and resealing
- Inconsistent sealant finishes from plot to plot
Projects at colleges like Westminster Kingsway College, 0.8 miles east of Belgravia, tend to run to term dates, so the mastic is planned tightly.
What to look for in a quote
- Health and safety accreditation such as CHAS
- How they handle RAMS and site documents
- Will CSCS-carded applicators be on site?
- The named product and why it was chosen