Fire-rated sealing and fire stopping in South Street, Greater London
Fire stopping for South Street, from a contractor working since 2005. Fully insured, with a 12-month guarantee.
- Head-of-wall gaps with no fire seal
- Improvised or mixed-product fire seals
- Openings found when ceilings come down for a refit
Fire stopping near South Street
Send drawings, photos or a joint schedule, or tell us about the site, and we’ll come back with a fixed quote.
How we handle fire stopping in South Street
Where pipes, cables and other services cross a compartment wall or floor, the opening around them has to be closed so fire and smoke can’t move between compartments. Our job is fitting fire-rated and intumescent sealant at those service penetrations, and along linear gaps, where it is the specified product. Each seal follows the manufacturer’s tested detail. The enquiries we see most involve expanding foam used as fire stopping and fire-stopping items raised at inspection or handover, on pipe penetrations, small duct penetrations where the tested detail allows and linear gaps at wall heads. Looking for mastic applicators who cover South Street? Mastic Doctor has worked for contractors, FMs and building owners since 2005.
Fit-outs and M&E works in London buildings often leave service penetrations open behind ceilings and in risers. If sealant is the specified product we fit it to its tested detail, and if the detail needs something else, you’ll hear it from us.
Whoever the client is, the cover is the same: a 12-month guarantee on our workmanship. It doesn’t extend to damage, faults in the building or work by others, and we’re upfront about that.
- Where
- South Street (TN16)
- Wider area
- Greater London
- Cover
- 12 months on every job
- Quote
- Quoted before any work starts
- Call
- 01277 525 020
- Page updated
- 3 November 2026
Why deal with it now?
A seal that doesn’t match its tested detail gives false comfort. Correcting it means cutting it out and starting again with the specified product, and doing it once, properly, is cheaper. Getting scaffold, permits or access booked in South Street takes effort, so while access is arranged it pays to renew all failing joints, not just the worst.
Quantities, awkward access and phased working all shape the price. Site requirements like inductions and permits play a part as well.
Why choose Mastic Doctor in South Street
- 12-month guarantee on workmanship
- Constructionline member
- One number for every site we cover
- CHAS accredited
Read how commercial sealant jobs are priced and our accreditations and insurance.
Our process
Occupied buildings need a little choreography. The work area is signed and kept contained, with routes through the building left open and move on in phases so staff and visitors can carry on around us. All of Greater London is in the ULEZ, and kerbside space in South Street can be scarce. Let us know about any on-site parking or loading arrangements when you send the job details.
- The specification and schedule come first, so we know which details apply.
- Access, permits and the order of areas are agreed with the site team.
- We compare every service penetration with its tested detail before sealing.
- Foam, ordinary sealant and debris come out.
- Backing and fire-rated sealant are installed to the detail and tooled.
- We tell you about openings that need a different product.
Before we start on site
- Tell us which areas need to stay in use
- Share your working hours and any access restrictions
- Move anything stored against the joints
Request a quote
Pricing a project or setting a maintenance budget? Send the scope and any drawings, and we will return a fixed quote that you can work with. For a chat about it beforehand, speak to us on 01277 525 020 or email the details over.
Read more
Looking after the joints
Your facilities or cleaning team can help the joints last. Share these points with them:
- Agree the fire-stopping specification before services go in
- Look above ceilings when tiles are lifted for other jobs
- Keep product data and details in the fire safety file
- Keep general-purpose fillers away from compartment walls
New services after handover are a common way fire stopping gets breached. A short check at the end of each job saves a long hunt later.
On fit-outs, get the fire-stopping specification agreed before the services go in. The designer can then choose details that suit the services planned, and installation follows the programme.
What sealant work can’t fix
A few problems need another trade or a different fix, and we say so rather than covering them up:
- Openings that need collars, wraps, batts or boards rather than sealant
- Issuing fire ratings or certificates for seals
- Fire doors, dampers or other fire safety equipment
If you are not sure, just ring 01277 525 020 or email a schedule or drawings and we’ll give you a straight answer.
Joints and surfaces we work on
- Linear gaps at wall heads
- Service gaps in risers
- Joints between fire-resisting walls and floors
- Small duct penetrations where the tested detail allows
- Pipe penetrations
- Cable penetrations
Different surfaces, different methods
Cables and cable bundles
Cable penetrations are frequently sealed with fire-rated sealant where the detail allows. Bundle size, cable type and the space between cables all matter, so we check before sealing.
Small ducts
Small ductwork can sometimes be sealed with sealant where the tested detail includes it. Larger or fire-rated ductwork usually needs a different solution set by the designer and we flag that rather than guess.
Questions about South Street
How does the move away from BS 476 affect penetration seals in South Street?
Approved Document B loses its BS 476 references from 2 September 2029, and BS EN 13501-2 becomes the route, subject to transitional arrangements. Our part doesn’t change: the specified product, to its tested detail.
Can you work at a site such as Biggin Hill Airport Trading Estate, by South Street?
Yes. Estates, retail parks and business parks around South Street, Biggin Hill Airport Trading Estate among them, are all within reach. Photos and a short description are enough for a first look.
Will your applicators have CSCS cards?
Yes. We use CSCS-carded applicators.
How do you deal with asbestos in old sealant?
Asbestos is possible in some older mastics, particularly in buildings from before 2000. Before we disturb old sealant in an older building, we ask to see the asbestos register or survey, and work stops until any suspect material has been tested. We don’t remove asbestos-containing materials.
Do you offer coloured sealant?
It depends on the product. Some ranges are wide, others limited, so we’ll confirm the colours available for the specified product with the quote.
Which sealant will you use?
The specification comes first, if there is one. Without one, the joint decides: its movement, its surfaces and what it has to cope with.
When can you be on site?
Give us your site hours and any access windows in your enquiry, and we’ll schedule the work to suit. Our office runs Monday to Friday, 8am until 5pm.
Compartment walls and floors in South Street
Every new tenant in a London building tends to bring new cabling, and with it new holes through compartment walls. We seal to the specification and the product’s tested detail, working within the building’s permits. Fire stopping of openings and penetrations in England falls under Approved Document B. The national BS 476 classes are due to drop out of it from 2 September 2029, leaving the European BS EN 13501-2 route, subject to transitional arrangements. We install whatever has been specified, to the product’s tested detail.
On estates like Biggin Hill Airport Trading Estate, 1.8 miles north-west of South Street, the wall between office and warehouse is often fire-resisting, and cables through it need the specified seal. In a building such as Church of St Mary the Virgin, any service penetration through a fire-resisting wall should be sealed to the specified detail. Wherever services are added at a hospital such as Tandridge Priory (3.2 miles south of South Street) the compartment line has to be made good with the specified product.
South Street is about 4 miles north-east of Oxted, in Greater London. We cover South Street and the rest of Greater London, with the same fixed quotes and 12-month guarantee as everywhere else. South Street is one of 764 places in Greater London on our list for service penetrations. There’s a separate page for London, roughly 15 miles from South Street.
Work on service penetrations is covered throughout TN16. Close to South Street, our area also takes in Tatsfield (1 mile west), Force Green (2 miles south-east), Titsey (2 miles south-west), Westerham (2 miles south-east) and Moorhouse Bank (3 miles south). Further afield, our area takes in London (15 miles north-west), Stockwell (14 miles north-west), Orpington (6 miles north), Wimbledon (14 miles north-west), Kennington (15 miles north-west) and New Cross (13 miles north).
Around South Street
The closest station to South Street is Oxted station, about 3.7 miles south-west of the centre. Well-known places in the area include Tandridge Priory (3.2 miles south). Open spaces near South Street include West Kent Golf Course nature reserve and Betsom's Hill.
Work for main contractors and building owners
Building owners and managing agents use us on everything from one building to a spread of sites. One quote can cover more than one site, which keeps the paperwork simple.
Blocks and communal areas make up much of the work for housing associations and agents. Work can be phased so residents and staff keep access throughout, with each stage agreed with your site contact.