West Sussex · England
External & façade joints in Colwood, West Sussex
Specialist external mastic for Colwood: careful preparation, the right product and tidy work. Ask us for a quick quote.
- Moss and dirt in joints with no sealant left
- Failed sealant between panels on a façade
- Joints with sealant missing in places
About our external mastic in Colwood
Failed sealant is cut out, the depth set with closed-cell backing rod, and the joint resealed with a low-modulus sealant made for outside. We pick a colour that sits well with the wall. We are often asked to deal with cracked joints where brick meets render or frames and plants rooting in failed movement joints, across copings & trims, concrete & block and façade panels.
External sealant needs dry, clean surfaces, so work around Colwood is planned for dry weather. Tell us about access to all sides of the building, including outbuildings and garages.
There’s a 12-month guarantee on every job, whatever its size.
- Where
- Colwood (RH17)
- Region
- West Sussex
- Cover
- One year on every job
- Quotes
- A clear price before we start
- Telephone
- 0345 464 0079
- Updated
- 26 October 2026
Landlords, agents and businesses in Colwood
From a single let to a portfolio, the work is the same standard: old sealant fully removed, joints prepared properly and a one-year guarantee.
Hotels need rooms back in use, so we plan the work room by room around your bookings where we can. Hotel work is part of what we do, alongside homes and businesses.
What happens on the day
There isn’t much for you to do on the day. Point us to the joints and we’ll get on with it. The job generally takes a few hours to a few days, depending on the length of joint and the access from start to finish. Somewhere like Colwood needs a little journey planning: tell us about narrow lanes, gates, long drives and where we can park. We bring what the job needs, so it can be finished in one trip where possible.
- First, the joints are inspected and the access agreed.
- We cut out the old mastic and rake out anything in the joint.
- The faces are brushed clean and primed where the product requires it.
- Backing rod sized to the joint goes in to set the depth.
- The exterior sealant is applied, tooled and checked along its length.
How to prepare
- Tell us about access, such as stairs, a lift or high-level joints
- Try not to wet indoor joints just before the visit
- On commercial sites, let us know about site rules
Ask for a quote
There’s no standard price list, as no two jobs are quite the same. Instead, we send you a clear quote for your job. To arrange one, ring 0345 464 0079 or drop us an email.
Related advice
DIY versus a professional finish
A DIY attempt does not rule out a professional job. We remove it and do the joint properly, so tell us about it when you ask for a quote.
Too much sealant is as bad as too little. A heavy bead looks messy and copes badly with movement, and getting the depth right matters as much as the look.
What external mastic looks like in Colwood
With historic houses such as Tyes Place (about 3.4 miles north-east) nearby, there’s older building stock in the area around Colwood as well as newer homes. In older buildings, older walls and rooflines need a sealant that moves with them and suits the material. Compared with the north and west, the South East gets less rain, yet outdoor joints still have to be sealed dry, so jobs are booked with the weather in mind.
Tyes Place, about 3.4 miles north-east, is one of the historic houses in the wider area around Colwood, and older homes nearby need a sealant that suits their walls.
Colwood is about 5 miles north-west of Burgess Hill, in West Sussex. We carry out external mastic for homes and businesses in Colwood and the surrounding area, as part of our work across West Sussex. Across West Sussex, we cover 371 places, Colwood among them. You can also see our page for Crawley, about 8 miles away.
Every address in RH17 is within our area for external mastic. Local streets include Earwig Lane and Cross Colwood Lane, all of which we cover. If you’re just outside Colwood, we cover Crabtree (1 mile north-west), Lower Beeding (2 miles north-west), Slaugham (3 miles north), Plummers Plain (3 miles north) and Monk's Gate (3 miles north-west). Further out, we also cover Crawley (8 miles north), Horsham (6 miles north-west), Worthing (15 miles south-west), Haywards Heath (6 miles east), Burgess Hill (5 miles south-east) and East Grinstead (13 miles north-east).
Landmarks near Colwood
We work in homes and buildings around Leonardslee, among other places. Nearby you will also find The Dene Hospital (3.8 miles south-east) and Cuckfield Museum (3.7 miles east). Green spaces nearby include Blunts Wood and Paiges Meadow.
What we can’t put right
Before you book, it’s worth knowing the limits:
- Walls that need new movement joints cut into them
- Render that’s blown, hollow or coming away
- Structural movement, which needs a surveyor or engineer
If you’re not sure, just call 0345 464 0079 or email us and we’ll give you a straight answer before you book.
Where we work in Colwood
- Brickwork movement joints
- Copings & trims
- Render & cladding joints
- Façade panels
- Concrete & block
- Joints between brick and frames
Places near Colwood
Also in Colwood
What we are called out for in Colwood
Buildings move more than people expect. Clay bricks expand slightly over their life, concrete and block shrink, and everything moves with temperature and wet. The sealant in the movement joints takes that strain.
Most people get in touch when they notice one of these:
- Damp patches traced to an open external joint
- Cracked joints where brick meets render or frames
- Old sealant gone brittle and cracked
- Movement joints filled with mortar instead of sealant
Around Colwood, as everywhere, external mastic is only as good as the preparation behind it.
Comparing quotes
- Whether they’re fully insured
- Whether the sealant suits the joint
- How the joint is cleaned and prepared
- Is VAT in the price?
Looking after it afterwards
How long the joints last depends on use and care. We suggest:
- Point out the joints to other trades
- Do not let climbing plants root in the sealant
- Leave the joints unpainted unless we’ve said otherwise
- Keep high-pressure jets off the joints
Don’t let soil, plants or ivy build up against the new joints. Anything that holds water against the joint wears it out sooner.
Leaks behind façade panels and render often go unseen. When it finally shows inside, the joint may have been open for years, so it’s worth resealing at the first signs.
Questions from Colwood
Will you come out to Colwood?
Yes. Colwood is within the area we cover, which takes in towns, villages and rural addresses. We work across London and the South East. Let us know about access, parking and anything unusual about getting there when you book.
Do you cover Colwood for external mastic?
Yes. We work across London and the South East, and Colwood is part of that. You can phone 0345 464 0079 or email us and tell us what needs doing, and we’ll send you a clear quote.
How long does external mastic last?
That varies with the weather the wall faces, how much it moves and the sealant used. Sealant is a maintenance item, so check the joints once a year.
When is the sealant fully cured?
Cure times vary by product and the temperature. Before we leave, we will tell you the cure time.
Can you seal joints between two different materials?
Yes. Where different materials meet is one of the most common joints we seal. We use a flexible sealant suited to both surfaces, primed where needed.
How do I get a quote for external mastic in Colwood?
It depends on the job, so we quote each one individually. For a quick quote, ring 0345 464 0079 or email us and tell us what needs doing and where.
How long does the job take?
It depends on the size of the job, but most jobs take anything from a few hours to several days, depending on the building. We’ll give you a better idea when we quote.
I’m a tenant. Can you help?
We can work for tenants, landlords or agents. Just make sure your landlord agrees.
Leave it or put it right?
Pointing a movement joint with mortar might seem a neat fix, but it locks the joint solid. The wall then cracks somewhere else. The correct repair is a flexible sealant with the right backing. Around Colwood, older homes often have timber in their floors and frames, where water from a failed joint can cause rot if it’s left.
Leaving a failed joint usually makes the job bigger, not smaller, as water and mould keep getting in. If you’re not sure whether it needs doing, call 0345 464 0079 or email us for an honest opinion and a quote.
Why choose Mr Mastic in Colwood
- We never seal over old sealant
- A 12-month guarantee on all work
- Sanitary silicone with an anti-fungal additive in wet areas
- Approved under the ARBOMaster scheme
Read our cost guide or what customers say.