Hertfordshire · England
Chandler's Cross Fire Rated Sealant
Fire-stopping gaps in Chandler's Cross need attention? We cut out the old, prepare the joints and apply the right sealant, with a 12-month guarantee.
- Sealant items on a fire risk assessment action list
- Cracked or shrunken fire-rated sealant
- Gaps left after a refit or conversion
Why act early in Chandler's Cross
An unsealed gap lets smoke and fire get round a wall that was built to hold them back. A proper seal lets the wall do its job again, and the sealing itself is often a contained piece of work. Older cottages and farmhouses around Chandler's Cross can have timber floors and frames, and water through a failed joint can rot timber if it’s left.
A failed joint rarely gets cheaper to fix by waiting. If you are unsure, phone 0345 464 0079 or drop us an email for an honest opinion and a quote.
What you get with us
- 180+ five-star Google reviews
- Sanitary silicone with an anti-fungal additive in wet areas
- Trusted Arbo and Everbuild sealants
- More than 20 years in sealant work
Read our cost guide and what customers say.
Fire rated sealant in Chandler's Cross, done properly
We can work through a building room by room or floor by floor, noting the locations and products as we go. That record is useful for your files and for whoever looks at the building next. If you are dealing with unsealed gaps around fire door frames and gaps around pipes and cables through fire-resisting walls, we can help, on door frames, linear gaps and plasterboard & masonry alike.
If you have holiday lets, a converted barn used for business or a community building near Chandler's Cross, the washrooms, kitchens and any fire-rated joints need the same care as a big site.
Whatever the size of the job, you get the same one-year guarantee.
- Place
- Chandler's Cross (WD3)
- Wider area
- Hertfordshire
- Cover
- A year, on every job
- Quote
- Quoted before any work starts
- Phone
- 0345 464 0079
- Updated
- 26 October 2026
Aftercare tips
Aftercare is simple, and it makes a real difference:
- Photograph sealed gaps before they’re covered up
- Look in service cupboards and ceiling voids from time to time
- File the fire-stopping record where your assessor can find it
- Check whether a sealant can be painted before decorating over it
Tell other trades that the gaps have been sealed, and make sure anything they disturb is resealed with a suitable product. Later work is a common cause of damaged fire stopping.
Any job that breaks through a wall or ceiling should include resealing. Catching it then saves a separate visit later.
How it works
Before we leave, we go over the finished joints with you. The visit itself normally takes a few hours for a handful of gaps, and longer for a whole building, depending on how much there is to do. Somewhere as small as Chandler's Cross, access is often the only tricky part. If the job is outside, mention outbuildings, exposed walls and how to reach them.
- First we work through your list or survey, measuring each gap and checking what it’s formed in.
- Anything that is not fit for the job comes out, and the gap is cleaned.
- We put in whatever backing or fill the product detail specifies.
- Fire-rated or intumescent sealant is applied to the right depth and tooled.
- Finally, we list where we worked and what we used, for your records.
Before we arrive
- Tell us about any water getting in
- Mention any tricky access
- Move anything stored near the joints
Ask for a quote
There’s no standard price list. Instead, your job gets its own clear quote. To get started, ring 0345 464 0079 or email us.
Advice
When to call us in Chandler's Cross
Door frames are a common weak spot. The architrave hides the gap between frame and wall, so it’s easy to leave unsealed when doors are changed.
Signs it’s time to call us include:
- Ordinary sealant used where a fire-rated product was needed
- Gaps where walls meet ceilings or slabs
- Sealant items on a fire risk assessment action list
- Fire seals that have cracked with movement
For landlords with property near Kings Langley station, new cables or pipes through a fire-resisting wall leave a gap that needs the right sealant.
Before you book anyone
- What guarantee comes with the work
- What preparation is included
- What happens if they find a problem under the old sealant
- What the cure time is
Chandler's Cross questions
I let a flat near Kings Langley station. Can you help?
Yes, rental work is part of what we do. You can phone 0345 464 0079 or drop us an email with the address and a few details, and we’ll give you a fixed price before work begins.
Is Chandler's Cross in your area for fire rated sealant?
Yes. Our work covers London and the South East, and Chandler's Cross is part of that. You can ring 0345 464 0079 or send us an email and let us know what needs doing, and we will give you a clear quote.
Do you have insurance?
Yes. Mr Mastic is fully insured.
Does someone need to be in?
If the work is inside, we need someone to let us in. After that, you can carry on with your day.
Can you fill the gap behind a fire door frame?
Yes. The joint between frame and wall is sealed with a fire-rated sealant, to the product’s details. The door leaf and its hardware need a door specialist.
Do you remove the old sealant?
Yes, always, and completely. New silicone doesn’t stick to old silicone, so the joint is cleaned back first.
Can new sealant go over the old?
No. New silicone won’t bond to old silicone, and anything trapped underneath, including mould and water, stays there. We remove it all first.
Do you hold any approvals?
Yes. We are ARBOMaster approved, the scheme for applicators of Arbo sealants.
Different surfaces, different methods
Door frames
Our work is the joint between frame and wall. The door leaf, its seals and closer need a door specialist and we will mention anything we notice.
Plasterboard walls
In plasterboard walls, the condition of the board edge matters. Crumbling edges are cleaned back before the sealant goes in.
What we cannot put right
Before booking, it’s worth knowing the limits too:
- Deciding what fire stopping a building needs
- Certifying a building or signing off its fire safety
- Openings too large for sealant, which need batts, boards or another system
If in doubt, phone 0345 464 0079 or email us and we will say what we think.
Surfaces we seal
- Service penetrations
- Linear gaps
- Door frames
- Pipe & cable gaps
- Flats & HMOs
- Plasterboard & masonry
Work for landlords, hotels and businesses
We work for landlords and agents as well as householders. Resealing between tenancies keeps a property looking cared for.
We also work for businesses, from offices to washrooms and kitchens. On commercial sites, working times can be discussed when we quote.
Towns and villages near Chandler's Cross
Also in Chandler's Cross
Fire rated sealant in Chandler's Cross: local notes
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 work to the specification you are given, installing the product to its tested details.
If you look after a building such as York House School, gaps opened by contractors for new cabling are a common finding in schools and offices.
Chandler's Cross is about 2 miles north of Rickmansworth, in Hertfordshire. If you need fire rated sealant in Chandler's Cross, it’s easy to get a quote: please ring 0345 464 0079 or send us an email. We cover Hertfordshire from our Crawley base, Chandler's Cross included. Our area takes in 381 places across Hertfordshire, large and small. There’s also a page for London, about 20 miles away.
Work in WD3 works the same way as everywhere else we cover. We cover properties on Chandler's Lane, White Shack Lane and Fir Tree Hill. Other places close to Chandler's Cross include Micklefield Green (1 mile west), Bucks Hill (1 mile north-west), Loudwater (2 miles south-west), Sarratt (2 miles north-west) and Hunton Bridge (2 miles north-east). We also work in nearby towns such as Watford (3 miles east), Hemel Hempstead (5 miles north), St Albans (8 miles north-east), Welwyn Garden City (14 miles north-east), Harpenden (11 miles north-east) and Hatfield (11 miles north-east).
Near you in Chandler's Cross
We work in homes and buildings around Croxley Danes School. The nearest railway station is Kings Langley station, roughly 2.4 miles north. Well-known places in the area include Charter Place (2.9 miles south-east) and Watford General Hospital (2.9 miles south-east). The countryside around Chandler's Cross includes Chorleywood Common and Tumbling Bay.