Fire stopping in Cosham
Our CSCS-carded applicators take on fire-rated and intumescent sealing of service penetrations and linear gaps in Cosham and the surrounding area. Send details for a fixed quote.
- Fire seals cut back for extra cables and never reinstated
- Penetration schedules that need working through
- Open linear gaps along the top of fire-resisting walls
Fire stopping in Cosham
Share the site address and what’s failing, and we’ll reply with a fixed quote or arrange a visit.
Fire stopping in Cosham, done properly
We are commercial sealant applicators, CHAS accredited and a Constructionline member, with CSCS-carded applicators on site. We don’t hold a third-party fire-stopping installer certificate and we’d rather say that up front. We install the specified fire-rated sealant to its tested detail, and our workmanship carries a 12-month guarantee. Most enquiries involve improvised or mixed-product fire seals and fire seals cut back for extra cables and never reinstated, on service gaps in risers, linear gaps at wall heads and small duct penetrations where the tested detail allows. Searching for sealant specialists in Cosham? Mastic Doctor has worked for contractors, FMs and building owners since 2005, CHAS accredited and a Constructionline member.
In places the size of Cosham, fire-resisting walls and floors are found in schools, care homes, health centres and mixed-use buildings. Specified fire-rated sealant goes around new services there, built to match the manufacturer’s detail.
Work we carry out comes with a 12-month guarantee. Should something we installed fail, give us a call on 01277 525 020 or email us and we’ll come back to it.
- Location
- Cosham (PO6, PO3, PO2)
- Wider area
- Portsmouth
- Cover
- 12 months on every job
- Quote
- A fixed quote before we start
- Call
- 01277 525 020
- Page updated
- 3 November 2026
After the work
For the best life from the joints:
- Look above ceilings when tiles are lifted for other jobs
- Foam or ordinary sealant is never a fire-seal repair
- Brief every trade that openings they make must be sealed
- Have penetrations checked while they can still be seen
Never top up a fire seal with foam, ordinary silicone or filler. Repairs need the same product and detail as the original.
Looking at service areas on a regular cycle pays off. A cracked or disturbed seal found early is a small job.
Diagnose, treat, sign off
We follow your site rules from the start: sign-in, induction and whatever permit system the building uses. With the paperwork done, we take the joints in the sequence agreed with you, and each area is checked before we leave it. If neighbouring businesses or buildings around Cosham need work too, visits can be combined. Mention the building’s opening times and we will work within them.
- First we go through the drawings, schedule or specification for the seals.
- Every penetration is compared with its detail: wall or floor type, service, gap size and depth.
- Unsuitable fillers and loose debris are taken out of each opening.
- We fit the backing the detail asks for, to the stated depth.
- Fire-rated or intumescent sealant is gunned in to the specified depth, then tooled.
- If an opening needs something other than sealant, we tell you instead of improvising.
Getting the site ready
- Share the asbestos register for older buildings
- Move anything stored against the joints
- Send any specification or drawings in advance
Quotes
Send us photographs, drawings or a joint schedule are often enough for a fixed quote. If the job needs a look first, we will arrange a site visit.
Advice
For managing agents and facilities managers
We work for building owners and managing agents on sealant work across single buildings or whole portfolios. One quote can cover more than one site, which keeps the paperwork simple.
FMs need a contractor who is easy to get on site. Tell us what site paperwork you need, such as RAMS, an insurance certificate or CSCS details, and we will confirm with the quote.
Towns and villages near Cosham
More services for Cosham
What sealant work can’t fix
Some faults sit outside our scope, and we point that out rather than sealing over them:
- 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
Not sure which it is? You can ring 01277 525 020 or email us and we will tell you honestly.
Joints and surfaces we work on
- Linear gaps at wall heads
- Small duct penetrations where the tested detail allows
- Pipe penetrations
- Cable penetrations
- Joints between fire-resisting walls and floors
- Service gaps in risers
Questions about Cosham
Can you work at a site such as Oak Park Industrial Estate, by Cosham?
Yes. Our area takes in Cosham and its surroundings, with estates and business parks such as Oak Park Industrial Estate included. A few photos and the unit address let us price the work.
Is a smaller place like Cosham outside your area?
Not at all: smaller places are covered as well as towns. London and every South East county are within our area. We plan jobs in smaller places so return trips are kept to a minimum.
How long does a job like this take?
That varies with the scale of the job, but the work 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’ll give you a timescale with the quote.
Is the BS 476 change in 2029 relevant to fire stopping?
For buildings in England, Approved Document B removes BS 476 references from 2 September 2029. Classification to BS EN 13501-2 becomes the expected evidence, though transitional rules apply. Scotland follows its own Technical Handbook, including clause 2.1.14 on service penetrations.
Can you reseal penetrations after our M&E works?
Yes. Send the schedule or marked-up drawings and the specified product details and a fixed quote follows. Work can run area by area behind the M&E trades keeping pace with the programme.
What do you charge?
There isn’t a price list, because every site is different. Send photographs or drawings and we will price it at a fixed figure.
Is your workmanship covered by a guarantee?
Yes, for 12 months. If our installation fails in that time, we return and fix it.
How the job changes by surface
Plastic pipes
Plastic pipes soften and collapse in a fire. Some intumescent sealants are tested on smaller plastic pipes. We confirm material and size first and tell you if sealant isn’t the right product.
Cables and cable bundles
Cable penetrations are frequently sealed with fire-rated sealant where the detail allows. The detail limits bundle size and the gaps between and around cables.
Fire stopping in Cosham: the local picture
Fire stopping of openings and penetrations in England falls under Approved Document B. From 2 September 2029, BS 476 references are being taken out of Approved Document B, leaving BS EN 13501-2 classification as the route, subject to the Government’s transitional arrangements. What we install is set by the specification, and it goes in to the tested detail. Central London is about 62 miles from Cosham. Offices around the capital are refitted often, and the cabling that follows can breach fire-resisting walls.
Theatres, wards and plant rooms at sites like Queen Alexandra Hospital, 0.6 miles north of Cosham, all have compartment walls crossed by services. For a unit at a centre such as Victory Retail Park, 2.6 miles to the south of Cosham, penetration seals are worth checking after each shop fit. For an estates team at a campus like University of Portsmouth - Langstone Campus, which lies south of Cosham, summer M&E works are normally followed by a round of penetration sealing.
Cosham is about 2 miles south-west of Purbrook, in Portsmouth. Our applicators travel to Cosham for work on service penetrations. Cosham is one of 19 places in Portsmouth on our list for service penetrations.
Commercial sites across PO6, PO3 and PO2 are covered. Among the streets we cover are Dean Road, Park Lane and Elgin Road. Cosham sits on or close to the A397, useful when we plan access and materials. Sites close to Cosham are covered too, including Wymering (1 mile north-west), Hilsea (1 mile south), Drayton (1 mile east), Widley (1 mile north-east) and Paulsgrove (1 mile west). Further afield, our area takes in Southsea (4 miles south), Milton (3 miles south), Landport (3 miles south), Portsea (3 miles south-west), Portsmouth Point (4 miles south-west) and Fratton (3 miles south).
What’s near Cosham
In Cosham, that means premises near The First Post pub, Alexandra Park and Springfield School. Cosham has its own railway station: Cosham station. Nearby you’ll also find Tricorn Centre (2.9 miles south) and World War I Remembrance Centre (1 mile south-east). The countryside around Cosham includes Southmoor Nature Reserve and Portsdown Hill.
Site staff or a sealant specialist?
Paperwork matters too. Many sites expect CSCS cards, RAMS and proof of insurance, and our CSCS-carded applicators are used to working under those rules.
Redoing a failed joint normally costs more than getting it right at the outset, because the whole bead must be removed and the faces cleaned back again. For that reason, many FMs and contractors use a sealant specialist from the outset.