West Sussex · England
Window Mastic in Crawley Down
Mastic around window and door frames, sills and patio doors for householders, landlords and businesses in Crawley Down. Fully insured, ARBOMaster approved and guaranteed for a year.
- Mastic that has split away from the wall
- Damp patches on the reveal after heavy rain
- Gaps where the sill meets the wall
Window mastic for homes and businesses in Crawley Down
Most frames have an outside joint and an inside one. Outside, the mastic keeps rain out; inside, the joint between frame and plaster stops draughts and tidies the reveal. Either or both can be done. If you have old mastic that has gone black or come away and gaps between the frame and the inside reveal, we can put it right, whatever the surface.
Around Crawley Down, conservatories, garden rooms and patio doors are often part of the house. Those joints need the same attention as the main windows, and any older timber or sash windows need a sealant that suits them.
All of our work is guaranteed for twelve months, in Crawley Down and everywhere else we cover.
- Location
- Crawley Down (RH10)
- Wider area
- West Sussex
- Guarantee
- One year on every job
- Quote
- Quoted before any work starts
- Telephone
- 0345 464 0079
- Last updated
- 26 October 2026
What the job involves on each surface
uPVC windows
We clean the frame edge carefully so the plastic is not marked, then the sealant goes in between frame and wall and tooled smooth.
Patio & French doors
Patio and French doors have the longest joints on most houses. The threshold and the bottom corners take the most water, so we pay close attention there.
What we do, step by step
A visit follows a simple pattern: we look at the joints together, protect the area around them, do the work and clear up. It normally takes anything from an hour or two to a full day, depending on how many frames there are. A visit to Crawley Down is planned like any other: the time, the access and where to park are agreed in advance. If the work is outside, the weather plays a part, as sealant needs a dry surface.
- We check how each frame can be reached safely.
- Old, cracked mastic is removed completely.
- Frame and wall are cleaned and must be dry before sealing.
- Backing rod fills deep voids and the sealant goes in on top.
- We tool the joint so water runs off, then clear up.
How to prepare
- Keep pets and children clear of the area while we work
- On commercial sites, let us know about site rules
- Let us know if you’ve seen damp or leaks
Get a quote
It all starts with a short chat. Tell us what’s wrong, where it is and how much there is, and we’ll explain how we’d tackle it. Whenever you are ready, ring 0345 464 0079 or email us.
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Your questions about window mastic in Crawley Down
Can you help a landlord with a rental near East Grinstead station?
Yes, rental work is part of what we do. Just ring 0345 464 0079 or email us and tell us about the property, and we’ll give you a clear quote.
Is Crawley Down within the area you cover?
Yes, we do. We work across London and the South East, from towns to the smallest places. Longer journeys are simply planned in advance.
How long will my window job take?
Allow a morning for a couple of windows and a door. Access and how stubborn the old mastic is affect the time most.
Can you work on commercial sites?
Yes, regularly. We can plan bigger jobs in stages to suit the site.
Which products do you use?
It depends on the joint: anti-fungal sanitary silicone in wet areas, and other sealants where joints move or face the weather. We use products from Arbo and Everbuild.
Can new window sealant be painted?
Silicone generally won’t take paint. If you plan to paint, tell us first and we can use a paintable sealant where it suits the joint.
Does someone need to be in?
It depends on the job. For work indoors, someone needs to let us in, and for outside work we’ll agree access with you when we book.
Can you seal over the old sealant?
No. Fresh sealant doesn’t stick to old sealant, and anything trapped underneath, including mould and water, stays there. We remove it all first.
Windows and doors in Crawley Down
Historic houses like Saint Hill Manor (about 2.4 miles south-east) are a reminder that the area around Crawley Down has older buildings as well as new. Where a home is older, older timber frames in brick or stone need a different approach from a modern uPVC window. The South East is one of the drier parts of the UK, yet outdoor joints still have to be sealed dry, so jobs are booked with the weather in mind.
For an older house near a landmark such as All Saints Parish Church, frames set in older brick or stone need a sealant that suits the wall as well as the frame.
Crawley Down is about 3 miles west of East Grinstead, in West Sussex. Crawley Down gets the same service as everywhere we cover: old sealant removed completely, careful preparation and a one-year guarantee. Our West Sussex coverage runs to 371 places, Crawley Down among them.
All of RH10 is covered for window mastic. If you need window mastic at a property on Station Road, Forest Close and Burleigh Way or anywhere close by, our applicators can take on the job. Nearby, we also carry out window mastic in Furnace Wood (1 mile north), Snow Hill (1 mile north), Turners Hill (1 mile south), Domewood (1 mile north) and Felbridge (2 miles north-east). Within a short drive, we also cover Crawley (5 miles west), Horsham (11 miles west), Haywards Heath (9 miles south), Burgess Hill (12 miles south), East Grinstead (3 miles east) and Broadfield (6 miles west).
Local landmarks in Crawley Down
We work in homes and buildings around Imberhorne School. For rail, the closest station is East Grinstead station, roughly 2.5 miles east of the centre. Other landmarks nearby include Queen Victoria Hospital (3.5 miles east) and Effingham Park Motor Museum (1.4 miles north-west). The countryside around Crawley Down includes Hedgecourt Lake.
How to look after the new joints
Joint life depends on how it’s used and looked after. We suggest:
- Repaint timber before it’s bare
- Look round the frames every year or so
- Clean frames with a soft cloth and soapy water
- Avoid blasting the frames with a pressure washer
Check the drainage slots in the frames aren’t blocked, so water can run away instead of sitting against the joint.
Wet, windy weather is when failed mastic shows itself, but sealant goes on best when frames and walls are dry. Sorting cracked mastic early means the joint is sound before the bad weather.
Should I try it myself first?
Sealing over old silicone is the commonest DIY error. New silicone will not bond to old, so it peels away and traps moisture behind it. Everything old must be removed first.
Overfilling a joint is a classic DIY mistake. A heavy bead looks messy and copes badly with movement, and getting the depth right matters as much as the look.
Quotes for window mastic in Crawley Down
You’ll get a clear quote before work begins. It’s based on:
- When we can work, for business premises
- How many rooms, windows or areas are involved
- The type of sealant required
- Whether there’s mould to deal with
There are no prices on our website, because each job is priced on what it involves. For a quick quote, please phone 0345 464 0079 or send us an email and we will talk you through it.
What we need to know
You do not need to know the technical terms. Just tell us:
- Access, such as stairs, a lift or height
- The rough size of the job
- Where the job is, and your postcode
- Any previous sealing or DIY work
We quote each job on its own. Simply ring 0345 464 0079 or send us an email and describe the job.
Nearby places to Crawley Down
More services for Crawley Down
Do you need window mastic in Crawley Down?
Older frames were often sealed with products that set hard. Once it has hardened, the frame’s movement tears it from the wall, leaving a hairline gap down one side.
Look out for any of the following:
- Gaps where the sill meets the wall
- Sealant in the wrong colour for the frame
- Mastic that has split away from the wall
- Damp patches on the reveal after heavy rain
Rented homes near East Grinstead station change hands often, and cracked frame mastic tends to show up as a draught or damp complaint, so it’s worth checking between lets.
Comparing quotes
- Is the old sealant removed completely?
- How the joint is cleaned and prepared
- Which sealant they’ll use, and why
- When the joint can take water or movement
What we can’t put right
In fairness, some problems need a different trade:
- A door that needs adjusting, rehanging or new seals
- Misting between the panes of a double-glazed unit (that needs a new unit)
- Rotten timber, which needs a joiner first
If you’re not sure, just phone 0345 464 0079 or drop us an email and we will give you a straight answer.
Joints and surfaces we work on
- uPVC windows
- Window sills
- Timber windows & doors
- Composite doors
- Patio & French doors
- Aluminium frames