Mastic sealing for building owners and managing agents in New Cross, Greater London
Mastic sealing for building owners, managing agents and housing associations across New Cross, carried out by CSCS-carded applicators. CHAS accredited and fully insured.
- Communal area joints that look neglected
- Movement joints with sealant missing
- Occupiers reporting cold air round windows
Mastic sealing for businesses in New Cross
Send drawings, photos or a joint schedule, or tell us about the site, and we’ll come back with a fixed quote.
What happens if it’s left?
Replacing mastic before water gets in is a planned job. Once water has tracked in, the repair list grows and occupiers notice. Failed sealant in a building in New Cross can quickly affect neighbours, tenants or the floor below. Dealing with it early is simpler for everyone.
The specified product makes a difference, as does the preparation each joint needs, from cutting out to priming and backing rod. Access, phasing and site requirements come into it too.
What you get with us
- Constructionline member for supplier checks
- Products installed to the manufacturer’s instructions
- Commercial sealant work since 2005
- Work carried out by CSCS-carded applicators
Take a look at what affects the cost and how we’re accredited.
Mastic sealing for commercial buildings in New Cross
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 are dealing with leaks at window and door perimeters and failed external movement joints, we can put it right, whatever the surface. One point of contact handles commercial sealant work in New Cross from the first photographs to the final walk-round, whether it’s one building or several.
Planning mastic work on a London block means notices to residents, access to flats and agreed working areas. We work to the agent’s notice and access plan, so residents know what’s happening.
Our workmanship is guaranteed for 12 months. If a joint we sealed fails because of how it was installed, we come back and put it right.
- Place
- New Cross (SE8, SE14, SE4)
- Region
- Greater London
- Cover
- A 12-month guarantee
- Quote
- Quoted before any work starts
- Phone
- 01277 525 020
- Updated
- 3 November 2026
Our process
Diagnose, treat, sign off: every visit follows that pattern. We inspect the joints and confirm what’s in scope, then we prepare and seal each joint with the specified product, and we finish with a walk round so the work can be signed off. In New Cross, most buildings stay in use during the work, so zones and timings are agreed with whoever manages the building. Areas are handed back as each section is finished.
- First we look at the mastic on each building and note what needs replacing.
- You get a fixed quote, priced per building where that helps your budgeting.
- The programme is fixed with you, including dates you can pass on to residents or tenants.
- Failed mastic is removed and the faces taken back to sound, dry material.
- Backing rod and primer go in where the joint and the product need them, then new sealant is applied and tooled.
- Each building is checked on completion and the work carries our 12-month guarantee.
Preparing the site
- Point out parking and an unloading spot
- Send any specification or drawings in advance
- Flag any permit to work we will need
Get a fixed quote
Photos, drawings or a schedule of the joints are often enough for a fixed quote. If the job needs a look first, we will arrange a site visit.
Related advice
Cost factors for mastic joints
These are the things that shape the price:
- Whether the work must be split into stages
- The total length or number of joints
- Joint width, depth and condition
- Specialist products, such as fire-rated or hygienic sealants
Pricing mastic joints depends on how many there are, their condition and the access, and any specification that applies. Call for a quote.
What to include in your enquiry
Diagnosis starts before we arrive. Let us know:
- Photos of the joints, close up and from further back
- The site address and postcode
- When you need the work done
- Approximate linear metres or a joint schedule
Send details, get a quote, we seal, guaranteed: that’s how every job runs. To take the first step, speak to us on 01277 525 020 or send photos by email.
Other services in New Cross
Blocks and managed buildings in New Cross
The 2 miles around New Cross include three care or nursing homes. Frame mastic on care buildings is best renewed elevation by elevation, with the manager deciding timings. London blocks come with residents to inform, access to agree and often a concierge or estate office to work with. We fit the programme to your notice periods.
Schools and community buildings such as Myatt Garden Primary School need frame and external mastic kept sound like any building. If you are responsible for a building such as St James's Church, frame and door mastic needs the same attention as any other property.
New Cross is about 3 miles south-east of London, in Greater London. New Cross sits inside our coverage and the rest of Greater London, with the same fixed quotes and 12-month guarantee as everywhere else. New Cross is one of 764 places in Greater London on our list.
We cover the SE8, SE14 and SE4 postcode districts. Streets here include Ivy Road, Mona Road and Avon Road. Main routes into New Cross include the A2209 and A2210, useful when we plan access and materials. Close to New Cross, our area also takes in St Johns (1 mile east), Telegraph Hill (1 mile south-west), Deptford (1 mile north-east), Nunhead (1 mile south-west) and Lewisham (1 mile south-east). Further afield, our area takes in London (3 miles north-west), City of Westminster (6 miles north-west), Marylebone (6 miles north-west), Kensington (8 miles west), St Pancras (5 miles north-west) and Shoreditch (4 miles north-west).
Local landmarks in New Cross
In New Cross, that means premises near Wickham Arms, Fordham Park and Addey and Stanhope School and the streets around them. Nearby too are St. Paul's (0.7 miles north-east) and Laban Centre (0.9 miles north-east). New Cross has its own railway station: New Cross station. Well-known places in the area include Fan Museum (1.2 miles north-east) and Greenwich Castle (1.5 miles east). Green spaces nearby include St. James's Park Lake and Tower Hill.
New Cross: questions and answers
Will you take on work at estates like New Cross Gate Retail Park, close to New Cross?
Yes. Our area takes in New Cross and its surroundings, with estates and business parks such as New Cross Gate Retail Park included. Send details of the unit and the work through our quote form for a quick quote.
Will you work in a care home in New Cross without moving residents out?
Yes. We work around residents’ routines, a room or two at a time. Tell us about any infection-control or safeguarding requirements and we will work to them.
Can you seal joints high up on a block?
Every block is different. How upper joints are reached is agreed before work is booked so there are no surprises.
Can you take on resealing for a block portfolio?
Yes. Managing agents, property factors in Scotland, housing associations and landlords with block or commercial portfolios are our main clients for this work, and we quote building by building or as a programme.
How long before the joints can be used?
The product and site conditions decide that. Some products skin over quickly but need longer to cure fully, and we confirm it before leaving site.
What paperwork can you provide?
Tell us what site paperwork you need (RAMS, insurance certificate, CSCS details) and we’ll confirm with the quote. We are CHAS accredited and a Constructionline member.
Is any job too small?
Whatever the size, the process is the same: details, then a fixed price, then sealing, then a 12-month guarantee.
What sealant work can’t fix
We check first that sealant really is the fix. It isn’t the answer for:
- Water coming in from the roof or rainwater goods
- Leaks through the frame itself rather than the perimeter
- Misted or failed double-glazed units
If you’re not sure, just speak to us on 01277 525 020 or send details through our quote form and we’ll give you a straight answer before you book.
Surfaces we seal
- Balcony and threshold joints
- Communal entrances and stairwells
- Shopfronts below residential blocks
- External wall and movement joints
- Communal kitchens and washrooms
- Window and door perimeters on blocks
Surface by surface
Communal areas
We keep entrances and stairs open throughout. We work in sections so access is never blocked.
Window and door perimeters on blocks
Window and door perimeters are where most mastic failure shows. We remove the failed mastic, prepare the faces, add backing rod if the joint is deep and reseal.
Signs you need mastic sealing in New Cross
Poor preparation explains many failed joints. Without clean, sound faces and a primer where the product needs one it comes away from one face.
It’s worth sending us details if you spot any of the following:
- Old repairs sealed over failed mastic
- Leaks at window and door perimeters
- Communal area joints that look neglected
- Open joints in brickwork or panels
Landlords with units on estates such as New Cross Gate Retail Park (to the north-west of New Cross) can bring frame, door and external mastic across several units into one programme.
Before you book anyone
- Whether their applicators hold CSCS cards
- Whether primer will be used where the manufacturer specifies it
- What level of public liability insurance do they hold?
- How they handle RAMS and site documents