Construction Mastic in Roundshaw
Mastic packages for new-build and refurbishment projects across Roundshaw, carried out by CSCS-carded applicators. CHAS accredited and fully insured.
- New external sealant already peeling away
- Caulk cracking where joints are moving more than expected
- Mastic snags holding up handover
Construction mastic across Roundshaw
Share the site address and what’s failing, and we’ll reply with a fixed quote or arrange a visit.
Construction mastic in Roundshaw
On refurbishments, the mastic package typically includes cutting out old sealant as well as sealing new work. Old beads come out completely, as fresh silicone can’t grip old. After that, the joints are prepared and sealed to the specification. If you have caulk cracking where joints are moving more than expected and window and door perimeters that won’t pass inspection, we can put it right, whatever the surface. Looking for mastic applicators who cover Roundshaw? We’ve been sealing commercial buildings since 2005, CHAS accredited and a Constructionline member.
The ULEZ covers the whole of Greater London, so contractors’ vehicles on a job in Roundshaw must meet its standards or pay the daily charge. Add booked delivery slots and limited storage, and a London mastic package needs planning before the first bead.
Every job ends the same way: guaranteed. You get a 12-month guarantee on our workmanship, and we explain exactly what that covers when we quote.
- Location
- Roundshaw (SM6, CR8, CR0)
- Region
- Greater London
- Guarantee
- 12 months on every job
- Price
- Quoted before any work starts
- Phone
- 01277 525 020
- Last updated
- 3 November 2026
Contractors’ notes for Roundshaw
A 2-mile radius around Roundshaw takes in plenty of hotels. When hotels extend or refit, the work is normally squeezed between peak periods, mastic included. Every borough of Greater London is inside the ULEZ, and that applies to contractors’ vehicles on any job in Roundshaw. Deliveries are booked and storage is tight, so mastic materials come in as needed.
When units on a site such as Silver Wing Industrial Estate (0.5 miles north-east of Roundshaw) are refurbished or reclad, the panel joints and window perimeters are part of the mastic package. Hospital estates such as Purley War Memorial Hospital, 1.2 miles south-east of Roundshaw, tend to grow and change in phases, often next to occupied wards, so facade and perimeter sealing has to fit the estates team’s plan.
Roundshaw is about 2 miles south-west of Croydon, in Greater London. We send applicators to Roundshaw for mastic packages. Roundshaw is one of 764 places we cover in Greater London. Sites around London have their own page, roughly 10 miles from Roundshaw.
Postcode districts covered here: SM6, CR8 and CR0. We cover commercial and managed buildings on Link Lane, Milton Road and Redwing Road. Just outside Roundshaw, we also work in Russell Hill (1 mile east), Bandonhill (1 mile north), Peaks Hill (1 mile south), Waddon (1 mile north-east) and Wallington (1 mile north-west). Further afield, our area takes in London (10 miles north), City of Westminster (11 miles north), Marylebone (11 miles north), Kensington (11 miles north), St Pancras (12 miles north) and Shoreditch (12 miles north).
Local landmarks in Roundshaw
In Roundshaw, that means premises near Wilson's School, Waddon Ponds and The John Fisher School. The nearest railway station is Wallington station, roughly 0.9 miles north-west of the centre. Nearby you’ll also find Purley War Memorial Hospital (1.2 miles south-east) and Croydon Airport Visitor Centre (0.6 miles east). The countryside around Roundshaw includes Roundshaw Downs and Duppas Hill.
What we are called out for in Roundshaw
On a live site, contamination is the biggest threat to a new joint. Dust, film adhesive, damp and grease on the joint faces prevent a proper bond so faces get cleaned, and primer goes on wherever the maker specifies, even on new work.
What tends to prompt an enquiry:
- New external sealant already peeling away
- A mastic package split between trades with no clear owner
- Missed perimeter joints on a new elevation
- Failed sealant in an existing building being refurbished
Further education sites such as Purley Language College (1.3 miles south-east of Roundshaw) are extended and refurbished from time to time, with mastic often programmed into the summer break.
Before you book anyone
- How long is the guarantee, and what does it include?
- Whether old or failed sealant will be cut out, not overlaid
- Can the work be phased to keep areas open?
- How the joint faces will be prepared and primed
Places near Roundshaw
What else we do in Roundshaw
After the work
Your facilities or cleaning team can help the joints last. Pass these on to them:
- Allow flexibility for external sealing in damp or cold weather
- Share drawings and the specification as soon as possible
- Ask installers to correct oversized gaps first
- Record the products used in the O&M file
Our 12-month guarantee covers the workmanship from sign-off. The guarantee covers how we sealed, not later damage by other trades which is why protection after sealing matters.
Frames with gaps too wide for sealant need sorting before the mastic goes on. Sealant stretched over an oversized gap won’t last, so the installer needs to correct it first. We flag them as soon as we see them.
Common questions from Roundshaw clients
Is a hospital such as Purley War Memorial Hospital somewhere you can work?
Yes, healthcare and care buildings are part of our work. Before anything starts, the estates team agrees permits, inductions and infection-control measures with us.
Can you work around term dates at a campus such as Purley Language College?
Yes. Education sites normally want the work in vacations or in phases during term, and we plan to suit. Tell us which site documents you need, such as RAMS, our insurance certificate or CSCS details, and they’re confirmed with the quote.
Can you send site paperwork?
Requirements differ from site to site, so tell us what you need and we’ll confirm it when we quote.
When can you be on site?
Mention the site’s hours and access windows in your enquiry, and we’ll schedule the work to suit. You can reach the office between 8am and 5pm, Monday to Friday.
Can fire-rated sealing at service penetrations be included?
It can be part of the package where specified. Record requirements are confirmed at quote stage.
Do you offer coloured sealant?
Often, yes. Many products come in a range of standard colours, and matching to RAL references or surrounding finishes is often possible. We confirm what’s available for the specified product when we quote.
How long do sealant joints last?
There isn’t a single answer, because life depends on how much the joint moves, how exposed it is and how it’s cleaned and used. Regular checks let you plan resealing before leaks or damage.
General trades versus a specialist
General builders and handymen seal joints, but it isn’t their main trade. A specialist prepares properly, controls joint depth and picks a product with the right movement class.
What you see is the finished bead, but most of the work is hidden. Correct depth, the right primer and a sealant matched to the movement are easy to get wrong without experience.
For managing agents and facilities managers
For main contractors, we work as the sealant subcontractor, on new build and refurbishment alike. We work to your programme, your specification and your site rules, with CSCS-carded applicators on site.
We work for building owners and managing agents on sealant work across single buildings or whole portfolios around Roundshaw. Several sites can go on one quote, so there’s one set of paperwork to deal with.
What happens if it’s left?
Patching snags as they appear can feel quicker than a proper close-out. But one planned snagging pass through each area usually clears more for less disruption. Snagging can be priced as a separate stage. Getting scaffold, permits or access booked in Roundshaw takes effort, so while access is arranged it pays to renew all failing joints, not just the worst.
The work involved drives the cost: stripping out, preparation, sealing, access and phasing. Call for a fixed quote and we will explain how it’s made up.
Why clients in Roundshaw choose us
- A Constructionline member, so easy to vet
- Joints cleaned back to sound surfaces
- Colours chosen to suit frames, cladding or finishes where possible
- Colours confirmed for the specified product
See what affects the cost and our accreditations and insurance.
From enquiry to sign-off
Working in a building that stays open takes some planning. We sign and contain the area we’re in, keep walkways clear and move on in phases so staff and visitors can carry on around us. In Roundshaw, 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.
- Drawings, specification and programme come to us.
- Quantities are measured and a fixed price returned.
- We agree with the site team which areas come first.
- Each area is sealed when it’s released.
- Every joint is cleaned, set to depth and sealed with the specified product.
- Snags are cleared and the package signed off with our 12-month guarantee.
Before we start on site
- Arrange parking or a loading space
- Flag any permit to work we will need
- Send your site hours and access windows
Request a quote
To get a fixed quote, ring 01277 525 020 or email drawings and photos. Our quote form is another easy route.