Wokingham · England
Window & door mastic in California, Wokingham
Window mastic for California and the surrounding area: careful preparation, the right product and tidy work. Ask us for a quick quote.
- Damp patches on the reveal after heavy rain
- White mastic on grey or black frames
- Gaps left after new windows were fitted
Window mastic for homes and businesses in California
Mr Mastic’s applicators have more than 20 years’ experience with window and door sealants. We are fully insured ARBOMaster approved applicators, and we give a 12-month guarantee on the work. If you have sealant in the wrong colour for the frame and black, perished sealant on frames, we can help, whatever the surface.
Homes in small places like California often stand in the open, with little to shelter their windows from wind and rain. Exposed frames and sills lose their mastic sooner than sheltered ones.
There’s a 12-month guarantee on every job, whatever its size.
- Location
- California (RG40)
- Region
- Wokingham
- Cover
- 12 months on all our work
- Price
- A clear quote up front
- Telephone
- 0345 464 0079
- Updated
- 26 October 2026
Aftercare tips
Good habits help new joints last longer. Our tips:
- Keep jet washers away from the mastic
- Walk round the house once a year and look at the joints
- Avoid harsh chemicals near the mastic
- Ventilate rooms so frames don’t stay wet inside
Clean the frames with mild soapy water, and keep solvents and harsh chemicals off the joint.
Water trapped behind a failed joint can start rot in timber frames and sills. Rotten timber needs a joiner, not a sealant, so early resealing is worth it.
The process
On the day, we start by going over the job with you, so there are no surprises. Surfaces next to the work are protected before any work starts. The work generally takes most of a day for a typical house, less for a few frames. Somewhere as small as California, access is often the only tricky part. If the job is outside, mention outbuildings, exposed walls and how to reach them.
- First we look at every frame and agree the list.
- The old mastic is cut out and the surfaces cleaned back.
- Deep gaps are filled with backing rod to set the depth.
- New exterior sealant goes on in a matching colour and is tooled smooth.
- We clear up and check every joint is fully closed.
Before we arrive
- Mention any parking rules near the property
- Tell us about any previous sealing or DIY attempts
- Where the joints are inside, avoid wetting them before we arrive
Ask for a quote
Quotes start with a quick conversation. Tell us what’s wrong, where it is and how much there is, and we’ll explain how we’d tackle it. Whenever you’re ready, ring 0345 464 0079 or drop us an email.
Advice
Should I try it myself first?
If you do try it yourself, take your time over the preparation: take out all the old sealant, make sure the joint is clean and dry, and give it the full cure time. If it does not work out, we can still put it right.
The biggest DIY mistake is sealing over old sealant. New silicone won’t bond to old, so it peels away and traps moisture behind it. Everything old must be removed first.
Why deal with it now?
Not every sealant suits a window. Decorators’ caulk and bathroom silicone aren’t designed for outside joints that move. A low-modulus exterior sealant keeps its stretch through hot and cold weather. Around California, older homes often have timber in their floors and frames, where water from a failed joint can cause rot if it’s left.
The cost depends on the size of the job, how hard the old material is to remove and access to the work. We give a clear quote before we start.
What you get with us
- 180+ five-star Google reviews
- Quality sealants from Arbo and Everbuild
- ARBOMaster approved applicator
- Colour picked to suit the job
Read what affects the cost and what customers say.
Questions from California
Will you come out to California?
Yes, California is covered. We work across London and the South East, from towns to the smallest places. Longer journeys are simply planned in advance.
I let a flat near Crowthorne station. Can you help?
Yes, landlords and agents are among the people we work for. You can ring 0345 464 0079 or email us with the details for a clear quote.
When is the sealant fully cured?
Different products cure at different speeds, so follow the cure time we give you when we finish.
Can you do several jobs on one visit?
Yes. Tell us about everything you’d like done.
Can you seal the gap between the frame and the plaster indoors?
Yes. Draughts often come through the inside gap too, so sealing both is often worthwhile.
How long does it take to reseal the windows on a house?
The work takes most of a day for a typical house, less for a few frames. Access and the amount of old mastic make the biggest difference.
Is the new sealant paintable?
Silicone generally will not take paint. If you plan to paint, tell us first and we can use a paintable sealant where it suits the joint.
Do I have to be there?
We need access to the joints, so we will agree that with you when we book. For inside work, that normally means someone being in.
Common problems we fix in California
Timber windows bring their own problems. Mastic painted over many times cracks with the paint, and timber moves with moisture as well as temperature.
It’s worth asking for a quote if you see:
- A bead that does not match the frame
- Leaking joints at the ends of sills
- Rushed sealant from a window installation
- Mastic that is falling out in pieces
Rented homes near Crowthorne station change hands often, and renewing tired window mastic between tenants heads off draught and damp complaints.
Questions to ask before you book
- Which colour the sealant will be
- Are they insured?
- Whether all the old sealant comes out first
- How hidden problems are handled
For landlords and businesses
Housing providers, facilities teams and property managers book us too. We can quote a run of properties together.
We regularly work with letting and managing agents. Tell us the address, the job and how access works and we will quote.
How the job changes by surface
Patio & French doors
Patio and French doors have the longest joints on most houses. Most leaks start at the bottom corners, so they get particular care.
Window sills
Stone and concrete sills have their own joints, including the one between the sill and the frame above. We seal those with a sealant suited to masonry.
Towns and villages near California
Also in California
What window mastic looks like in California
Rainfall in the South East is lower than in much of the UK, though outdoor sealant still has to go onto a dry joint, so the forecast decides the day.
Homes close to Church of St James include some older properties, and the windows may be timber, sash or later replacements, and each needs the right sealant against the wall. For site and facilities teams at buildings such as Gorse Ride Junior School, larger buildings have plenty of frames, and the mastic around each one ages.
California is about 3 miles south-west of Wokingham, in Wokingham. From the centre of California to the outskirts, window mastic is available for homes and businesses alike. Our area takes in 35 places across Wokingham, from the larger towns to small villages. For nearby work, see our Reading page.
All of RG40 is within our area for window mastic. Whether your property is on Warren Lane, White Horse Lane and Fernbank or anywhere close by, our applicators can take on the job. If you are just outside California, we cover Arborfield Garrison (1 mile west), Finchampstead (1 mile south-east), Barkham (1 mile north), Langley Common (1 mile north-west) and Eversley (1 mile south-west). Further out, we also cover Reading (7 miles north-west), Wokingham (3 miles north-east), Woodley (5 miles north), Earley (5 miles north-west), Crowthorne (3 miles east) and Lower Earley (4 miles north-west).
Near you in California
Locally, jobs take us to homes and businesses close to The Queen's Oak pub, Bohunt School Wokingham and Shepperlands Farm Nature Reserve, among other places. The nearest railway station is Crowthorne station, roughly 2.4 miles east. Nearby you will also find Beaumys Castle (4.7 miles west) and Wokingham Hospital (2.6 miles north-east). The countryside around California includes Horseshoe Lake and Holt Copse & Joel Park.