Greater London · England
Fire Rated Sealant in Southwark
Fire rated sealant in Southwark from a team with over 20 years’ experience. Rated 4.9 on Google from 180+ five-star reviews.
- Damaged fire sealant left by other trades
- Ordinary sealant used where a fire-rated product was needed
- Gaps where walls meet ceilings or slabs
Fire rated sealant in Southwark, done properly
Ordinary silicone or decorators’ caulk in a fire-stopping gap is not a fire-rated seal. We cut out the wrong material and reseal with a fire-rated product tested for that kind of gap. If you’re dealing with gaps filled with a product that isn’t fire-rated and cracked or shrunken fire-rated sealant, we can help, whatever the surface.
London blocks of flats carry pipes and cables through walls and floors in their common parts and service risers. For managing agents and building owners in Southwark, that can mean fire-rated sealant around service openings as well as resealing in shared washrooms and kitchens.
Our work is backed for twelve months, in Southwark and everywhere else we cover.
- Place
- Southwark (SE1, SE11)
- Region
- Greater London
- Guarantee
- A year, on every job
- Quotes
- A clear quote up front
- Telephone
- 0345 464 0079
- Updated
- 26 October 2026
Looking after it afterwards
Joint life depends on how it’s used and looked after. Here’s what we suggest:
- Look in service cupboards and ceiling voids from time to time
- Store the list of sealed gaps with your building paperwork
- Don’t fill fire-stopping gaps with ordinary foam or silicone
- Take photos of fire stopping before ceilings or boxing go back
Avoid covering a sealed gap with anything that isn’t part of the tested detail. If it needs repair, use the same type of product. Ask us if you are not sure which product was used.
An open gap isn’t only a fire issue: they also let noise, draughts and sometimes pests through. Sealing them early helps on every front.
What we do, step by step
When we get to you, we check the joints match what you told us. If we find something unexpected, we talk it through with you first. Most jobs then take a few hours for a handful of gaps, and longer for a whole building. Parking in much of London is by permit or pay-and-display, so it helps to know what’s near you in Southwark. It helps if you can point us to a visitor permit or a bay close to the door.
- Before starting, we go through the specification or action list with you.
- Each gap is measured and its substrate and service noted.
- Any non-fire-rated filler is removed and the faces cleaned.
- The specified fire-rated sealant goes in over any backing its detail requires.
- Every location is recorded with the product used for your files.
How to prepare
- Mention any tricky access
- Tell us if parking is tricky
- Plan for the work area to be out of bounds to pets and children
How to get a quote
Call for a quick quote, or email us if that is easier. Tell us about the joints that need doing and we’ll talk you through the work before giving you a price.
Advice
What affects the cost of fire rated sealant
Some jobs are bigger than they look, and some smaller. The main factors:
- Mould in or behind the old joints
- How many areas need sealing
- The number and length of the joints
- Access and height
What you pay reflects the work, not a rough estimate. That’s why we ask a few questions first.
What to tell us for a quote
The more you tell us, the more accurate the quote. When you ask for a quote, tell us:
- The rough size of the job
- Where the job is, and your postcode
- Any access issues, like height or stairs
- If someone has resealed it before
The more we know about the job, the more useful the quote. Let us know the location, the problem and roughly how many joints, and add photos by email if you can.
DIY versus a professional finish
If you do try it yourself, take your time over the preparation: remove every trace of old sealant, clean and dry the joint, and follow the product’s cure time. If it does not work out, we can still put it right.
Sealing over old silicone is the commonest DIY error. New silicone will not bond to old, so it peels away and traps moisture behind it. All the old material has to come out first.
Southwark questions
Is parking an issue for fire rated sealant in Southwark?
Parking in Southwark, as in most of London, takes a little planning: a visitor permit or a bay close to the door helps a lot.
Do you work for hotels and guest houses in Southwark?
Yes. Hotel and guest-house work is part of what we do. Work can be planned room by room, and out-of-hours working can be arranged.
Is the work guaranteed?
Yes: twelve months. If there’s a problem with our work in that time, tell us and we’ll put it right.
Do you seal gaps around fire door frames?
Yes, where the gap suits a sealant detail. Our work is the gap around the frame and we will tell you if we spot problems with the door.
Can ordinary silicone be used in a fire-stopping gap?
No. It might close the gap, but it isn’t a fire-rated seal. A tested fire-rated product is needed and we can apply it for you.
Will we have a record of what was sealed?
Yes. Locations and products are written up when we finish. Tell us if your assessor needs it in a particular format.
Can you tell me how many minutes the seal will last?
Ratings and certificates aren’t something we issue. What’s required is set by your assessor or designer, and the product’s tested details show what it achieves, and we install to them.
Do you offer different sealant colours?
Yes. Sealants come in white, clear, grey and other colours for many products, and we will agree it with you first.
Why it’s worth doing now in Southwark
Fire-rated sealants need more care than everyday sealant. How it’s installed changes how it performs, so we follow the maker’s details on every gap. In London conversions, one flat’s bathroom is often above another flat’s ceiling, and a slow leak from a failed seal can end up in the flat below. Putting it right early is much less trouble for homes in Southwark.
No two jobs are quite the same, so each one gets its own quote. The number of joints, how easy they are to reach and the sealant needed all play a part, and we’ll explain the quote if you ask.
Why choose Mr Mastic in Southwark
- Sanitary silicone with an anti-fungal additive in wet areas
- Full insurance on every job
- Over 20 years’ experience
- ARBOMaster approved applicator
Take a look at our cost guide or customer reviews.
What we’re called out for in Southwark
Gaps around door frames are easily missed. The gap between the frame and the wall is hidden behind the architrave, so it can be left open when a door is replaced.
People generally contact us when they notice one of these:
- New service routes left unsealed after building work
- Unsealed gaps where pipes and cables go through a wall
- Fire seals that have cracked with movement
- Damaged fire sealant left by other trades
If you look after a building such as Charles Dickens Primary School, fire-stopping around service openings should be restored whenever new services go in.
Questions to ask before you book
- Whether VAT is included
- What the cure time is
- How the joint is cleaned and prepared
- Who turns up on the day
Towns and villages near Southwark
Also in Southwark
What fire rated sealant looks like in Southwark
Commercial buildings in London often have strict access rules and limited loading, so out-of-hours working can be arranged where needed. There are hotels and other places to stay in and around Southwark. Hotel work can be planned room by room, with out-of-hours working where needed.
Rented homes near Elephant & Castle station change hands often, and new cables or pipes through a fire-resisting wall leave a gap that needs the right sealant. If you look after a church, hall or community building such as Borough Welsh Congregational Chapel, gaps around pipes and cables are worth checking after any building work there.
Southwark is about 0 miles north-west of London, in Greater London. Jobs in Southwark get the same care as everywhere else we work: old sealant removed completely, careful preparation and a 12-month guarantee. We cover 764 towns and villages across Greater London.
Our applicators cover all of SE1 and SE11 for fire rated sealant. Local streets include Borough Square, Trinity Church Square and Merrick Square. Main roads around Southwark include the A300 and B240, so getting to you is simple. We also cover Tower Hill (1 mile north-east), City of London (1 mile north), Aldgate (1 mile north-east), Bishopsgate (1 mile north-east) and Barbican Estate (1 mile north). Within a short drive, we also cover City of Westminster (3 miles west), Kensington (5 miles west), Walthamstow (7 miles north-east), Hampstead (5 miles north-west), Ruislip (14 miles west) and Brompton (3 miles west).
Around Southwark
Around Southwark, our work takes us to homes and buildings near London School of Musical Theatre, Little Dorrit's Playground and St Mary-at-Hill, among other places. Also close by are Ark Globe Academy (within half a mile south-east), The BFI Reuben Library (0.9 miles north-west) and The Gladstone Arms (less than half a mile north-east). The nearest railway station is Elephant & Castle station, about 0.5 miles south. A little further out are Gabriel's Wharf (0.7 miles north-west) and Baynard's Castle (0.8 miles north). Not far away are Ludgate Hill and Bellenden Road Nature Garden.
Different surfaces, different methods
Flats and HMOs
In flats and HMOs, the walls and floors between homes and common areas need sealing where services pass through. We seal the gaps your assessor has identified room by room.
Service penetrations
Wherever a service goes through a fire-resisting wall or floor, there’s a gap around it. We seal it with a product tested for that service and gap size.