Greater London · England
North Harrow Fire Rated Sealant
Fire rated sealant across North Harrow and nearby, with every bit of old sealant taken out first and a one-year guarantee.
- Unsealed gaps around fire door frames
- Holes left by a change of layout
- Gaps where walls meet ceilings or slabs
Fire rated sealant in North Harrow, done properly
Deciding which gaps need fire stopping is not our role; that comes from your fire risk assessor, designer or building control. Our part is applying the specified sealant carefully, to the right depth and with the right backing. If you have gaps left after a refit or conversion and standard silicone or caulk in a fire-stopping gap, we can help.
In London, a commercial job often starts with access: loading bays, building rules and lifts. For a building in North Harrow, we agree timings and access before anything starts, and room-by-room programmes can be planned where needed.
All of our work is guaranteed for twelve months, and the guarantee is the same wherever you are.
- Location
- North Harrow (HA2, HA1, HA5)
- Region
- Greater London
- Cover
- One year on every job
- Quotes
- A clear price before any work starts
- Phone
- 0345 464 0079
- Page updated
- 26 October 2026
What we’re called out for in North Harrow
Gaps around door frames are easily missed. The architrave hides the gap between frame and wall, so it can be left open when a door is replaced.
People generally contact us after spotting one of these:
- Gaps where walls meet ceilings or slabs
- Open gaps behind door architraves
- Sealant items on a fire risk assessment action list
- New service routes left unsealed after building work
For landlords with property near Harrow-on-the-Hill station, fire-rated sealant around pipes and cables through walls and floors needs making good whenever new services go through.
What to look for in a quote
- What preparation is included
- Who turns up on the day
- Which colour the sealant will be
- How long the guarantee is
Leave it or put it right?
Sealant isn’t the fix for every opening. Big openings, bundles of cables and plastic pipes may need batts, collars or wraps instead. We will say so if a gap needs something other than sealant. In a London flat, a failed joint rarely stays your problem alone: water can reach the neighbours below, and gaps in fire-rated joints affect the whole building.
Some things make a job bigger or smaller: the old material and how easily it comes out, any mould to treat, and whether the work is at height. We take all of that into account in your quote.
Why choose Mr Mastic in North Harrow
- We never seal over old sealant
- Trusted Arbo and Everbuild sealants
- We’re fully insured
- We leave the area clean and tidy
Take a look at our cost guide and customer reviews.
Commercial buildings in North Harrow
In England, the Regulatory Reform (Fire Safety) Order 2005 requires a fire risk assessment for workplaces and for the common parts of blocks of flats, 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. Many London buildings have tight access and loading restrictions, so out-of-hours working can be arranged where needed.
As a London address, North Harrow can be tricky for parking: tell us about permits, visitor bays or off-street space when you book. For buildings such as Church of St Alban, older buildings that have had new heating or wiring often have service gaps worth checking.
North Harrow is about 1 mile north-west of Harrow, in Greater London. From the centre of North Harrow to the outskirts, fire rated sealant is available for homes and businesses alike. North Harrow is one of 764 places in Greater London we cover. For nearby work, see our London page (13 miles or so).
Work in HA2, HA1 and HA5 is quoted and booked the same way as anywhere else. Fire rated sealant is available to properties on The Avenue, Pinner Road and Durham Road and the roads around them. We also cover the places around North Harrow: Rayners Lane (1 mile south-west), Harrow (1 mile south-east), Roxbourne (1 mile south-west), Eastcote (1 mile west) and Greenhill (1 mile east). Larger places within reach include London (13 miles south-east), City of Westminster (10 miles south-east), Marylebone (10 miles south-east), Kensington (9 miles south-east), St Pancras (11 miles east) and Shoreditch (13 miles east).
Landmarks near North Harrow
Locally, jobs take us to homes and businesses close to Nower Hill High School, Heathfield School and Headstone Manor Recreation Ground, among other places. For rail, the closest station is Harrow-on-the-Hill station, about 1.2 miles east. Other landmarks nearby include St. George's Shopping Centre (1 mile east) and Hilfield Castle (5 miles north). Open spaces near North Harrow include Northala Fields and Islip Manor Meadows.
Work for landlords, hotels and businesses
Water getting past a failed joint can damage the building, which matters even more when someone else lives there. Resealing at the right time is simple maintenance.
Failed sealant is one of the commonest items on a check-out report. We can quote for more than one property at once.
What we can’t put right
Sealant isn’t the answer to every problem, and we’d rather say so up front. It won’t solve:
- Openings too large for sealant, which need batts, boards or another system
- Construction that doesn’t provide fire resistance on its own
- Sign-off of the building, which sits with building control or your assessor
If in doubt, phone 0345 464 0079 or send us an email and we will say what we think.
Joints and surfaces we work on
- Door frames
- Flats & HMOs
- Service penetrations
- Plasterboard & masonry
- Pipe & cable gaps
- Linear gaps
Common questions in North Harrow
Is parking an issue for fire rated sealant in North Harrow?
London parking needs a little planning, so let us know about permits, bays or a driveway when you book. The visit is then planned around what’s available.
Do you work for landlords with property near Harrow-on-the-Hill station?
Yes, rental work is part of what we do. You can ring 0345 464 0079 or email us with the address and a few details, and we will give you a fixed price before we start.
How long will you be here?
It depends on the size of the job, but as a guide it takes anything from a few hours to several days, depending on how many gaps there are. We’ll tell you when we quote.
Do you hold any approvals?
Yes. We hold ARBOMaster approved applicator status and we’re fully insured too.
Can I add another job to the visit?
Yes, and it often makes sense. Combining jobs makes good use of the visit, so mention them when you ask for a quote.
Do you certify the fire stopping?
Ratings and certificates are not something we issue. What’s required is set by your assessor or designer, and the product’s tested details show what it achieves.
What does intumescent mean?
An intumescent material expands when it’s heated. Intumescent sealants are a type of fire-rated sealant.
Do you cover North Harrow?
Yes. We cover North Harrow and the rest of Greater London, as part of our work across South East England, London and Scotland. For a quote, phone 0345 464 0079 or drop us an email.
More services for North Harrow
How it works
Our applicators work methodically: protection first, then preparation, sealing and a tidy-up. Typically it takes a few hours for a handful of gaps, and longer for a whole building, and the area is left clean. In North Harrow, as in most of London, parking needs a little planning. A visitor permit or a nearby bay makes the visit run more smoothly.
- Before starting, we go through the specification or action list with you.
- We measure every gap and note what it’s in and what passes through.
- Unsuitable material such as ordinary foam or silicone is cut out.
- The specified fire-rated sealant goes in over any backing its detail requires.
- We hand over a list of locations and products.
Preparing for the visit
- Clear items away from the joints we’re working on
- Keep children and pets away from the work area
- Tell us about any previous sealing or DIY attempts
How to get a quote
To get a quote, call 0345 464 0079 or send us an email with the location and a short description of the problem. We will give you a clear price before any work starts.
Read more
Aftercare tips
After the cure time, these simple habits help:
- Photograph sealed gaps before they’re covered up
- Never patch a fire seal with standard sealant
- Do not paint over fire sealant until it has cured
- Tell trades working in the building that fire seals must be put back
Look at the sealed gaps as part of your routine walk-rounds. Watch for cracking, gaps or seals that have been disturbed and get them seen to.
It’s easiest to seal gaps while they’re few and easy to reach. Leave them and each new job adds another hole and the list grows.
How the job changes by surface
Door frames
The gap between a door frame and the wall around it needs sealing as well as the door itself. We seal that gap with a fire-rated sealant suited to the frame and wall.
Linear gaps
Head-of-wall gaps are often hidden above suspended ceilings. We seal them along their full length leaving no stretch unsealed.