Mastic Sealing in Harringay
Mastic sealing for building owners, managing agents and housing associations in Harringay. CHAS accredited, Constructionline member, with a 12-month guarantee on workmanship.
- Leaks at window and door perimeters
- Damaged joints in communal entrances and corridors
- Old repairs sealed over failed mastic
Mastic sealing in Harringay
Tell us what needs sealing and where, with photos or drawings if you have them, and we’ll price it.
Mastic sealing in Harringay, done properly
We diagnose before we prescribe: what has failed, what caused it and whether new sealant will actually solve it. Old mastic is removed entirely, the faces prepared, primer used where the maker specifies it and new sealant tooled in and backing rod used wherever a joint is deep. If you have failed external movement joints and water getting in round frames after rain, we can put it right, whatever the surface. Whoever orders the work in Harringay, the brief is normally the same: a clear scope, tidy work and joints that don’t fail again.
London’s ULEZ covers every borough, and parking and loading rules vary street by street. For block-wide work, a place to park and store materials saves time on every visit.
Work we carry out in Greater London comes with a 12-month guarantee. If an installation problem shows up, call 01277 525 020 or email a schedule or drawings and we will arrange a return visit.
- Place
- Harringay (N4, N15, N8)
- Wider area
- Greater London
- Guarantee
- A 12-month guarantee
- Price
- Fixed quote, scope in writing
- Call
- 01277 525 020
- Updated
- 3 November 2026
Your questions answered
Can work in a care setting near Harringay go ahead while residents are there?
Yes. We work around residents’ routines, a room or two at a time. Noise and disruption are kept to a minimum.
Can you cope with the access rules in a London building?
Yes. Inductions, permits and timed loading are routine for us in London. Share the building’s contractor rules and we will work to them. The ULEZ covers the whole of Greater London, which we allow for
Will you come and look before quoting?
It depends on the job. Simple work can often be priced from photos, and bigger or more complex jobs normally get a visit.
How do you reach windows on upper floors?
Every block is different. We agree access with you at quote stage so the fixed quote reflects it.
What guarantee do you give on resealing?
Our workmanship carries a 12-month guarantee, backed by public liability insurance.
Do you supply RAMS and insurance details?
We are CHAS accredited, a Constructionline member and carry public liability insurance. Tell us what site paperwork you need (RAMS, insurance certificate, CSCS details) and we’ll confirm with the quote.
Can weather delay the job?
Outside, yes. Sealant needs a dry joint and a temperature within the product’s range, so frost, rain or cold mornings can delay outside work. Inside work is seldom held up.
For owners and agents in Harringay
For a London block, the agent or landlord normally handles notices to residents and access to flats. We work to your notice and access plan. Harringay has four care or nursing homes no more than 2 miles away. For owners and operators of care buildings, window perimeters and external joints are best renewed in planned phases around residents.
If you own or manage units on a site such as Arena Shopping Park, which lies south of Harringay, failed mastic on frames, door surrounds and external joints can be dealt with unit by unit. Buildings close to stations like Harringay Green Lanes station, less than half a mile south of Harringay, are often flats over shops, with frame mastic to keep sound.
Harringay is about 2 miles north-west of West Hackney, in Greater London. We send applicators to Harringay for mastic joints, handled exactly as we handle every other area. Across Greater London, 764 places are covered, Harringay among them. Sites around London have their own page, roughly 6 miles from Harringay.
We cover the N4, N15 and N8 postcode districts. If your site is on Elyne Road, Denton Road and Warham Road or close by, we can quote for mastic joints. Just outside Harringay, we also work in Duckett's Green (1 mile north), West Green (1 mile north-east), St Ann's (1 mile east), Manor House (1 mile south) and Seven Sisters (1 mile east). Nearby towns on our patch include London (6 miles south), City of Westminster (5 miles south-west), Marylebone (5 miles south-west), Kensington (7 miles south-west), St Pancras (4 miles south) and Shoreditch (4 miles south).
Around Harringay
Around Harringay, our work takes us to commercial buildings near Chestnuts Park, Park View School and Moselle Upper School and the streets around them. You will also find The Salisbury pub (under half a mile north) and Church of St Andrew (1.1 miles south-east). There’s a railway station in Harringay itself: Harringay Green Lanes station. Other landmarks nearby include Montfichet's Tower (4.7 miles south) and Markfield Beam Engine and Museum (1.6 miles east). Open spaces near Harringay include Railway Fields and Highgate Hill.
What sets the cost
Sealant work doesn’t have a standard rate, because every site is different. What we take into account:
- Whether the work must be split into stages
- Whether old sealant has to be cut out first
- Induction, permit and paperwork requirements
- Quantities, in metres or numbers
Whether it’s a single area or a whole estate, the same things set the price: scope, access, product and programme. Call for a quote and we’ll put a fixed figure on it.
What to include in your enquiry
Good information means a firmer quote. When you get in touch, include:
- Clear photographs of the problem areas
- Your programme or deadline
- Where the site is, with the postcode
- Rough lengths or quantities, or drawings if you have them
Tell us about the building, the joints and when you need the work done, and a fixed quote will follow. The easiest way is to ring 01277 525 020 or send details through our quote form.
Keeping the joints sound
Once the work is signed off, these steps help:
- Ask residents or tenants to report leaks and draughts early
- Have the asbestos survey to hand for older buildings
- List the paperwork your organisation requires when you send details
- Plan resealing building by building rather than complaint by complaint
Where a paintable product was specified, it can be painted after curing. Silicone normally can’t be painted, so keep decorators off it.
Mastic fails gradually, then all at once in a wet spell. Resealing when cracking first shows avoids water damage and the complaints that come with it.
Common problems we fix in Harringay
Occasionally the substrate fails, not the sealant, such as crumbling render, brick arrises or frame edges. If the edges are unsound, we say so before quoting the sealing.
These are often picked up first by site or facilities staff:
- Brittle perimeter mastic across a building
- Patchy repairs in mismatched sealant
- The same joint failures repeated across a portfolio
- Failed external movement joints
Churches, halls and community buildings such as St Paul's Harringay are looked after by trustees and committees like any other owner, and their frames, doors and external joints need mastic renewed in time.
What your quote should include
- What level of public liability insurance do they hold?
- Are they CHAS accredited or on Constructionline?
- How they handle RAMS and site documents
- Their plan for phasing and protecting the area
Should maintenance staff do it?
Some joints are best left to specialists: fire-rated seals that must follow a tested detail, trafficked floor joints and external movement joints among them. A poor seal in places like these tends to cost more to put right later.
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.
Our process
Inspect, seal, sign off: every visit follows that pattern. First comes an inspection and agreement on scope, then the work is carried out to the specified product and detail, and we finish with a walk round so the work can be signed off. Most London premises stay occupied while we are on site, so we agree zones and timings with the building or facilities manager. Areas are handed back as each section is finished.
- A building-by-building inspection lists the failed joints.
- You get a fixed quote, per block or for the whole programme.
- We agree the programme and dates with you.
- Failed sealant is removed and the faces prepared.
- Joints are resealed and tooled.
- We check the finished work and confirm the guarantee.
Getting the site ready
- For older buildings, check the asbestos register before work
- Confirm the product named in the specification
- Warn occupants and staff about the work
Get a fixed quote
Photos, drawings or a schedule of the joints and a fixed quote comes back to you. If the job needs a look first, we will arrange a site visit.
Related advice
When something else is needed
Sealant solves a lot, but not everything, and we’re upfront when that’s the case. It won’t fix:
- Leaks from above rather than through a joint
- Cracked or crumbling render, brick or stone at the joint edges (we’ll tell you if so)
- Failed window or door frames, which need a window contractor
If in doubt, phone 01277 525 020 or email the details over and we’ll say what we think before you book.
What we seal
- Shopfronts below residential blocks
- Balcony and threshold joints
- External wall and movement joints
- Communal kitchens and washrooms
- Window and door perimeters on blocks
- Communal entrances and stairwells