Fire-rated sealing and fire stopping in Harmondsworth, Greater London
Fire-rated and intumescent sealing of service penetrations and linear gaps across Harmondsworth, by CSCS-carded applicators. Fully insured and CHAS accredited.
- Damaged fire seals in risers and voids
- Snag lists that include open service penetrations
- Unsealed openings around new pipes and cables
Fire stopping for Harmondsworth sites
Share the site address and what’s failing, and we’ll reply with a fixed quote or arrange a visit.
Leave it or put it right?
An improvised seal can look finished while offering no tested performance. Correcting it means cutting it out and starting again with the specified product. In a London building, a failed joint rarely affects only one party. Putting it right early is less disruptive than dealing with the consequences.
We don’t publish prices, because the scope varies so much from one building to the next. For a fixed figure, call for a quote.
Why clients in Harmondsworth choose us
- Health and safety: CHAS accredited
- One number for every site we cover
- Failed material removed, not covered up
- Work to your specification and the manufacturer’s guidance
Read how commercial sealant jobs are priced or our accreditations and insurance.
Fire stopping in Harmondsworth, done properly
It helps to set out our role at the start. The designer, fire engineer or building control decides which fire stopping is required; sign-off sits with them too. What we bring is careful installation of the specified sealant, to the maker’s guidance on sites in Harmondsworth. We work on small duct penetrations where the tested detail allows, cable penetrations and linear gaps at wall heads, and the usual reasons a site gets in touch are unsealed joints where partitions meet the slab and old intumescent sealant that has split away. For commercial sealant work in Harmondsworth, you deal with one contact from quote to sign-off, whether it’s one building or several.
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 will hear it from us.
The 12-month guarantee covers our workmanship: preparation, application and finish. Damage, later alterations by others and movement beyond what the joint was designed for sit outside it.
- Location
- Harmondsworth (UB7, TW6)
- Wider area
- Greater London
- Cover
- 12 months on our workmanship
- Price
- A fixed quote before we start
- Telephone
- 01277 525 020
- Page updated
- 3 November 2026
Common questions from Harmondsworth clients
What does the BS 476 change mean for fire-rated sealant in Harmondsworth?
From 2 September 2029, Approved Document B drops its BS 476 references in favour of BS EN 13501-2 classification, with transitional arrangements. The designer or fire engineer sets the specification, and we install the product to the manufacturer’s tested detail.
Can you seal around new services in a hotel near Harmondsworth?
Yes, where fire-rated sealant is the specified product. We match the product to the wall or floor and the services, and say if something other than sealant is needed.
Do you cover Harmondsworth?
Yes. Harmondsworth falls within our area, and the simplest way to start is to call 01277 525 020 or email a schedule or drawings.
Do you seal on top of existing sealant?
No. Failed sealant is removed and the faces cleaned back to sound, dry material first, since fresh sealant will not bond reliably to aged material.
Are your applicators CSCS-carded?
Yes. We use CSCS-carded applicators, which many sites require.
How long does a typical visit take?
It depends on the scope, though a typical visit typically takes a single visit for a short list of penetrations, or a phased programme for a whole building. Larger or phased jobs take longer, and we will give you a timescale with the quote.
Does weather matter for sealant work?
For external joints, yes. The joint has to be dry and within the product’s temperature range, so frost, rain or cold mornings can delay outside work. Inside work is seldom held up.
Service penetrations in Harmondsworth buildings
For England, the fire stopping of penetrations is dealt with in Approved Document B. Its BS 476 references are being withdrawn from 2 September 2029, with BS EN 13501-2 classification taking over, subject to transitional arrangements. What we install is set by the specification, and it goes in to the tested detail. The area within 2 miles of Harmondsworth holds a good number of hotels. In hotels, bedroom and corridor walls are typically fire-resisting, so services added in a refit need sealing with the specified product.
On estates like Skyport Industrial Estate, less than half a mile to the south of Harmondsworth, the wall between office and warehouse is often fire-resisting, and cables through it need the specified seal. For a hospital such as Hillingdon Hospital (2.8 miles north of Harmondsworth), penetration sealing is normally phased ward by ward, with infection-control rules agreed first.
Harmondsworth is about 1 mile south-west of West Drayton, in Greater London. Any commercial site in Harmondsworth is covered. Our Greater London coverage takes in 764 places. Our London page has more on work in that area (17 miles or so).
If you need fire stopping in UB7 and TW6, the process matches everywhere else we work: details, then a fixed price, then sealing and a 12-month guarantee. For a building on Moor Lane, Hatch Lane and High Street or nearby, send details and we will quote for service penetrations. Nearby places we also cover include Longford (1 mile south-west), Sipson (1 mile north-east), Heathrow (2 miles south-east), Harlington (2 miles east) and Stanwell (2 miles south) for service penetrations. Bigger towns within reach include City of Westminster (14 miles east), Marylebone (14 miles east), Kensington (12 miles east), Hampstead (14 miles east), Ruislip (7 miles north-east) and Brompton (14 miles east).
Local landmarks in Harmondsworth
Locally, jobs take us to sites close to Harlington Community School and The Five Bells Inn. The closest station to Harmondsworth is Heathrow Terminal 5 Rail station, about 1 mile south of the centre. Nearby you’ll also find British Airways Heritage Collection (3.5 miles north) and Harlington (1.4 miles east). The countryside around Harmondsworth includes Crane Meadows and Staines Reservoirs.
Diagnose, treat, sign off
Inspect, seal, sign off: that’s the shape of every visit. First comes an inspection and agreement on scope, then the work is carried out to the specified product and detail, and the job ends with a walk round and sign-off. The ULEZ covers the whole of Greater London, and parking near a job is rarely simple. If there’s a loading bay, a car park or a permit we can use, tell us when you send details.
- First we confirm the product and tested details named in the specification.
- Openings are measured and grouped by detail.
- Improvised fillers and failed sealant are removed.
- Where the detail needs backing, it goes in at the stated depth.
- We gun the sealant in to the specified depth around each service and tool it.
- Completed areas are checked with you, with the records agreed when we quoted.
What we need from you
- Agree which areas must stay open
- Send asbestos survey details if the building is pre-2000
- Move anything stored against the joints
Getting a fixed quote
Every job follows the same four steps: send details, get a quote, we seal, guaranteed. To take the first step, give us a call on 01277 525 020 or email us.
Read more
Different surfaces, different methods
Plastic pipes
In a fire, plastic pipework melts away and leaves an opening. Some intumescent sealants are tested on smaller plastic pipes, but many need a collar or wrap. We confirm material and size first and tell you if sealant isn’t the right product.
Masonry and concrete
Core-drilled holes are neat; broken-out ones rarely are. The gap is measured at the widest point against the detail’s limits, and any that don’t are flagged.
Towns and villages near Harmondsworth
What else we do in Harmondsworth
What we are called out for in Harmondsworth
Mixing products or improvising a detail breaks the link with the test evidence. An oversized gap, too shallow a bead, missing backing or two makers’ products combined are the usual culprits.
Site and facilities staff are often the first to spot these:
- Unsealed openings around new pipes and cables
- Fire seals cut back for extra cables and never reinstated
- Seals that don’t match their tested detail
- Open linear gaps along the top of fire-resisting walls
Hotels like Sheraton Heathrow Hotel, under half a mile to the south of Harmondsworth, are refurbished in phases, and each phase can open up compartment walls.
What to look for in a quote
- Which product they’ll use, and why it suits the joint
- Their public liability cover
- Will CSCS-carded applicators be on site?
- How long is the guarantee, and what does it include?
When to bring in a specialist
For most general trades, sealant is a sideline. A specialist brings correct preparation, depth control with backing rod and a product suited to that particular joint.
For a quick touch-up, site staff may be fine, but larger jobs are different: a specialist brings efficiency, a consistent finish and a 12-month guarantee.
When it isn’t the sealant
We seal joints; we don’t mend everything behind them. On its own, sealant can’t deal with:
- Deciding what a wall or floor needs, which belongs to the designer
- Large openings beyond what any sealant detail covers
- Signing off or certifying a building’s fire stopping
If you are not sure, just ring 01277 525 020 or use the quote form and we’ll give you a straight answer.
What we seal
- Joints between fire-resisting walls and floors
- Service gaps in risers
- Linear gaps at wall heads
- Cable penetrations
- Small duct penetrations where the tested detail allows
- Pipe penetrations