Greater London · England
St Luke's Fire Rated Sealant
Our applicators work in St Luke's on intumescent and fire-rated sealant around gaps, frames and service penetrations. Old material cut out, joints cleaned and sealed neatly and every job guaranteed for a year.
- Seals cut through by electricians, plumbers or data installers
- Open holes round services passing through fire walls
- Gaps where walls meet ceilings or slabs
Common problems we fix in St Luke's
Lots of unsealed gaps appear long after the building was completed. Electricians, plumbers and data installers drill through walls and ceilings and the hole round the new service is not always sealed again.
It’s worth asking for a quote if you see:
- Gaps flagged on a fire risk assessment
- Gaps filled with a product that isn’t fire-rated
- Open holes round services passing through fire walls
- Open joints along the top of partitions
Schools such as St Luke's CofE Primary School are buildings too, and service openings in fire-resisting walls need checking after any refurbishment.
Questions to ask before you book
- Whether the sealant suits the joint
- How the surfaces are prepared before sealing
- How much experience the applicator has
- The length of the guarantee
About our fire rated sealant in St Luke's
A gap around a door frame, a linear joint at the head of a wall and a hole round a pipe are each sealed differently. We check the size and the substrate before choosing the product, then apply it to the depth its tested detail calls for. We’re often asked to deal with damaged fire sealant left by other trades and open gaps behind door architraves, on plasterboard & masonry, linear gaps and flats & HMOs.
Commercial work in London comes with its own logistics: loading restrictions, building rules and tight access. For a building in St Luke's, we agree timings and access before anything starts, and room-by-room programmes can be planned where needed.
A one-year guarantee comes with the work, just as it does everywhere we cover.
- Where
- St Luke's (N1, EC1V, EC2A)
- Wider area
- Greater London
- Cover
- One year on every job
- Quotes
- A clear quote up front
- Phone
- 0345 464 0079
- Page updated
- 26 October 2026
Also near St Luke's
Other services in St Luke's
Work for landlords, hotels and businesses
Landlords and letting agents in St Luke's can book us as well as homeowners. Sealant work between tenants keeps a property looking cared for.
Letting agents often deal with us directly. Send the address, what’s needed and the access arrangements and we will quote.
FAQs for St Luke's
Do you work for landlords with property near Old Street station?
Yes. We work for landlords and agents as well as homeowners, and several properties can go on one quote. Just ring 0345 464 0079 or email us with the address and what needs doing, and we’ll give you a clear price.
Do you work for hotels and guest houses in St Luke's?
Yes, hotels and guest houses are among the places we work. A room-by-room programme keeps most rooms in use while the work goes on.
Can you match the sealant colour?
Yes. White, clear and grey are common, and other colours are available, and we’ll agree it with you first.
Is it messy?
Not at all. The area is protected while we work and cleaned up afterwards.
Do you carry out fire risk assessments?
No. We work from the specification you give us, and apply each product to its tested details.
Do you seal gaps around fire door frames?
Yes. We seal the gap between the frame and the wall with a suitable fire-rated product following the tested details. The door, its seals and closer are for a door specialist.
Is there any odour?
There can be a smell while the sealant cures. Ventilation helps.
What should I tell you?
Where the job is, what the problem is and roughly how big it is. Photos by email help too.
DIY sealant or a professional job?
If you are set on DIY, put the effort into preparation: take out all the old sealant, make sure the joint is clean and dry, and give it the full cure time. If it fails, we can still redo it.
The difference is mostly in the preparation and the product. Joints are cleaned back to sound surfaces and dried, and the sealant is matched to the joint and its conditions.
Leave it or put it right?
For some gaps, sealant is not the right answer and another system is needed. Large holes, cable bundles and plastic pipes can call for batts, collars or wraps. We will say so if a gap needs something other than sealant. In a flat in St Luke's, failed sealant seldom stays inside your own four walls: water from a shower or window joint can reach the flat below, and gaps in fire-stopping matter to everyone in the building.
Doing several joints on one visit is usually more efficient than separate visits, so it’s worth mentioning everything you’d like done. We will give you a clear quote for the lot.
Why choose Mr Mastic in St Luke's
- One-year guarantee on every job
- Tidy, careful work
- An ARBOMaster approved applicator
- Quality sealants from Arbo and Everbuild
See our cost guide or what customers say.
Workplaces and buildings in St Luke's
There are hotels and other places to stay in and around St Luke's. Hotel work can be planned room by room, with out-of-hours working where needed. Workplaces and the common parts of blocks of flats in England need a fire risk assessment under the Regulatory Reform (Fire Safety) Order 2005, which is often where open fire-stopping gaps are first noticed. We apply fire-rated sealant to the assessor’s or designer’s specification and the product’s tested details.
If you look after a church, hall or community building such as Jewin Welsh Presbyterian Chapel, gaps around pipes and cables are worth checking after any building work there. If you let a flat or house near Old Street station, new cables or pipes through a fire-resisting wall leave a gap that needs the right sealant.
St Luke's is about 2 miles north of London, in Greater London. St Luke's gets the same service as everywhere we cover: old sealant removed completely, careful preparation and a 12-month guarantee. Our Greater London coverage runs to 764 places, and St Luke's is one of them.
We work across the N1, EC1V and EC2A postcode area for fire rated sealant. Local streets include Long Lane, City Road and Moor Lane, and we cover them all. St Luke's is on the A1 and A501, which makes it straightforward to reach with everything needed for fire rated sealant. Close by, we work in Finsbury (1 mile south), Barbican Estate (1 mile south), Shoreditch (1 mile east), Hoxton (1 mile north-east) and City of London (1 mile south). Larger places within reach include City of Westminster (3 miles west), Kensington (5 miles west), Walthamstow (5 miles north-east), Hampstead (4 miles north-west), Ruislip (14 miles west) and Brompton (4 miles south-west).
Landmarks near St Luke's
We work in homes and buildings around Barts Health Archives, Charterhouse Square School and The Masque Haunt pub, among other places. Other local landmarks include St Mary-at-Hill (1.1 miles south), Central Foundation Boys' School (within half a mile east) and Artillery Ground (within half a mile south-east). There’s a railway station in St Luke's itself: Old Street station. Nearby you will also find Gabriel's Wharf (1.3 miles south-west) and Montfichet's Tower (0.9 miles south-west). For a walk, there’s St. James's Park Lake and Barnsbury Wood.
The process
Most of a good job is in the preparation, and we do not rush it. Joints are cleaned back and dried before anything new goes in. In total, it normally takes a few hours for a handful of gaps, and longer for a whole building. Many London jobs are in flats, so we come ready for stairs, narrow hallways and shared entrances. If the building has a concierge, managing agent or access rules, tell us when you book.
- First we work through your list or survey, measuring each gap and checking what it’s formed in.
- Old or unsuitable sealant is cut out and the gap cleaned.
- We put in whatever backing or fill the product detail specifies.
- We apply the fire-rated or intumescent sealant to the specified depth and tool it.
- We record the locations and products used for your records.
Before we arrive
- Mention any tricky access
- Tell us about any water getting in
- Tell us if parking is tricky
Getting a quote
Quotes start with a quick conversation. Tell us what’s wrong, where it is and how much there is. Whenever you’re ready, ring 0345 464 0079 or email us.
Advice
How the job changes by surface
Plasterboard walls
Holes in plasterboard are often cut roughly for services. Where a hole is bigger than the sealant’s tested range, it needs another approach and we will flag it.
Masonry and concrete
Core-drilled and broken-out holes in concrete are often irregular. We measure the gap at its widest point to make sure it suits the product.
Quotes for fire rated sealant in St Luke's
Your quote is based on your job. We take into account:
- Working hours on commercial sites
- How many rooms, windows or areas are involved
- The number and length of the joints
- Whether there’s mould to deal with
No two jobs are quite the same, so we quote each one individually. Size, access and the product the joint needs all make a difference.
Helping us quote
To help us quote quickly, please include:
- Any previous sealing or DIY work
- Where the job is, and your postcode
- What the problem is, such as mould, gaps, leaks or cracking
- If it’s domestic, commercial or a hotel
Asking for a quote is easy: tell us what needs doing and where, and roughly how big it is. Photos by email help us understand the job.