Wokingham · England
Crowthorne Sand Mastic
Sand mastic for Crowthorne, by sealant specialists with 20+ years’ experience. Rated 4.9 on Google from 180+ five-star reviews.
- Silicone on a period window that looks wrong
- Gaps round a timber door in stone or brick
- Old cement repairs round a window that have failed
Sand mastic in Crowthorne, done properly
For a listed home or one in a conservation area, ask your local planning authority if consent is needed before window work. Sand mastic is often favoured as a like-for-like material. We are often asked to deal with mastic worn away on windows facing the weather and mastic dropping out of the joint, on sash and case windows, stone surrounds and period & listed homes.
Crowthorne mixes older streets, where windows have often been replaced, with newer estates fitted with uPVC. In every case, the joint between frame and wall is what keeps water out.
All our work comes with a one-year guarantee.
- Location
- Crowthorne (RG45, RG40)
- Wider area
- Wokingham
- Guarantee
- One year on every job
- Quotes
- A clear quote up front
- Call
- 0345 464 0079
- Page updated
- 26 October 2026
How it works
Most of a good job is in the preparation, and we don’t rush it. Every joint is cleaned and dried before new material goes in. All told, the work takes a few hours per window, depending on the condition of the joints. For a job in Crowthorne, we need access to where the work is and somewhere nearby to park. For outside work, let us know about side access, gates and any upper-floor joints.
- First, we look at the surrounds with you and agree what needs doing.
- The loose and crumbling mastic is raked out and the joint cleaned.
- Large voids are packed out first, so the mastic isn’t too thick.
- The mastic is mixed, pressed into the joint by hand and shaped.
- We dress the surface so it sits neatly against the masonry.
Before we arrive
- Let us know about stairs, lifts or work at height
- Tell us if parking is tricky
- Mention any leaks or damp you’ve noticed
Get a quote
Want a quote for sand mastic? Please ring 0345 464 0079 or send us an email and tell us about the job. You will know what we plan to do, and what it will cost, before any work begins.
Related advice
Common problems we fix in Crowthorne
Timber swells and shrinks with the weather. That movement opens up the mastic joint little by little.
Look out for any of the following:
- Failed mastic on an exposed elevation
- Silicone on a period window that looks wrong
- Mastic dropping out of the joint
- Cracked mastic round a front door frame
If you look after a building such as Crowthorne Church of England Primary School, its window and door frames need their mastic kept sound, just like a home’s.
Before booking anyone
- Whether they’re fully insured
- Whether you can choose the colour
- What guarantee comes with the work
- What product goes in the joint
Keeping the joints in good condition
Joint life depends on how it’s used and looked after. We suggest:
- Do not paint over the new mastic
- Clear gutters so water doesn’t pour onto the windows
- Keep modern sealant off the mastic
- Look over the window mastic once a year
Avoid sealing over the mastic with silicone. If anything cracks, get it looked at before trying a quick fix.
Crumbling mastic lets rain into the joint. It can soak into the frame and the surrounding masonry, so renewing it early is worth it.
What sealant work can’t fix
Sealant isn’t the answer to every problem, and we’ll tell you before we start. Sealant won’t put right:
- Sashes that need overhauling
- Decayed frames that need repair
- Decisions on consent for listed homes
If you’re not sure, just call 0345 464 0079 or send us an email and we will give you a straight answer.
Surfaces we seal
- Tenement windows
- Period & listed homes
- Brick reveals
- Sash and case windows
- Stone surrounds
- Timber door frames
Work for landlords, hotels and businesses
A neglected joint can let water reach the structure, which is a bigger problem in a rented property. Keeping joints in good order is simple maintenance.
From a single let to a portfolio, you get the same standard of work: old sealant fully removed, joints prepared properly and a one-year guarantee.
DIY versus a professional finish
The difference is mostly in the preparation and the product. We take joints back to clean, dry surfaces, and the sealant is chosen for how the joint moves and where it is.
Too much sealant is as bad as too little. A thick, smeared bead looks untidy and doesn’t move well, and the joint depth matters as much as the finish.
What affects the cost of sand mastic
The quote reflects the job in front of us. We take into account:
- Whether the work is at height
- Whether old sealant or filler has to be cut out
- Whether there’s mould to deal with
- The size of the job
Every job is a little different, so we quote each one individually. The number of joints, how easy they are to reach and the sealant needed all play a part.
Helping us quote
To make quoting easier, please include:
- Any access issues, like height or stairs
- The rough size of the job
- The problem you’ve noticed
- Pictures of the joints, sent by email
There’s no standard price list. Instead, your job gets its own clear quote. To get started, call 0345 464 0079 or send us an email.
Crowthorne questions
Do you cover Crowthorne for sand mastic?
Yes, Crowthorne is within the area we cover. Our work covers London and the South East. Just ring 0345 464 0079 or email us with a few details of the job.
Is there a guarantee on sand mastic in Crowthorne?
Every job comes with our 12-month guarantee, wherever it is. We’re fully insured, and an ARBOMaster approved applicator.
Which products do you use?
The product depends on the job: anti-fungal sanitary silicone in wet areas, and other sealants where joints move or face the weather. Brands we use include Arbo and Everbuild.
What information do you need?
Where the job is, what the problem is and roughly how big it is. If you can, email a few pictures.
Are you ARBOMaster approved?
Yes. We’re an ARBOMaster approved applicator, which is run for the Arbo sealant brand.
Do I need to be at home?
That depends on where the joints are. For work indoors, someone needs to let us in, while outside work can sometimes be arranged differently.
Is it possible to paint over sand mastic?
Traditional guidance is not to paint over sand mastic. If you’re redecorating the window, ask us first and we will talk you through it.
Is it possible to take out silicone and use sand mastic instead?
Yes, it’s a common request. All the old silicone is removed first so the mastic can sit properly.
Towns and villages near Crowthorne
More services for Crowthorne
Frames and glazing around Crowthorne
The South East is one of the drier parts of the UK, though outdoor sealant still has to go onto a dry joint, so the forecast decides the day.
For an older house near a landmark such as Crowthorne Methodist Church, the windows may be timber, sash or later replacements, and each needs the right sealant against the wall. Letting a property close to Crowthorne station? Then cracked sand mastic around sash windows lets in the draughts tenants complain about.
Crowthorne is about 3 miles south-west of Bracknell, in Wokingham. Wherever you are in the RG45 postcode area, we cover sand mastic for homes and businesses. Crowthorne is one of 35 places in Wokingham we cover for sand mastic. There’s also a page for Reading, roughly 9 miles from Crowthorne.
We cover every part of the RG45 and RG40 postcode area for sand mastic. You will find streets such as Church Road East, Church Road West and High Street. Main roads around Crowthorne include the A321 and B3348, so getting to you is simple. If you are just outside Crowthorne, we cover Owlsmoor (1 mile south-east), Home Farm (1 mile north-east), Wooden Hill (2 miles north-east), Sandhurst (2 miles south) and Hanworth (2 miles north-east). We also work in nearby towns such as Reading (9 miles north-west), Wokingham (3 miles north-west), Woodley (7 miles north-west), Earley (7 miles north-west), Lower Earley (6 miles north-west) and Winnersh (5 miles north-west). Crowthorne is one of the larger places we cover in Wokingham.
Landmarks near Crowthorne
In Crowthorne, that means homes and buildings near King Edward VI Aston School, The Prince pub and Edgbarrow Woods, among other places. Crowthorne’s nearest station is Crowthorne station, about 1 mile south-west. Well-known places in the area include The Lexicon (3.7 miles north-east) and Pinewood Hospital (0.9 miles north). Green spaces nearby include Wildmoor Heath and Heath Lake.