Reading · England
Horncastle External Mastic
Professional external mastic in and around Horncastle, with every bit of old sealant taken out first.
- Sealant that has lost its bond to the brick or render
- Rigid filler in a joint that should flex
- Gaps where render, brick and frames meet
About our external mastic in Horncastle
Ground-floor and low-level joints are straightforward to reach. For joints higher up, give us some details of the building and we will confirm what’s needed to reach them safely. If you have gaps where render, brick and frames meet and damp patches traced to an open external joint, we can help.
Homes around Horncastle range from older cottages to newer houses, with walls and rooflines of every type. Older homes need their gutter and trim joints kept tight, newer ones their movement joints.
Your job is guaranteed for a year, as with all our work.
- Where
- Horncastle (RG30, RG31)
- Region
- Reading
- Cover
- One year on every job
- Quote
- Quoted before any work starts
- Telephone
- 0345 464 0079
- Last updated
- 26 October 2026
Why it’s worth doing now in Horncastle
Sealing over the top of old mastic does not hold for long. New sealant does not bond well to old, weathered sealant, so we always take the old sealant out. In an older home around Horncastle, damp from a failed joint can get into timber and plaster, which is far harder to put right than the sealant itself.
We don’t show prices on the website, because each job is priced on what it involves. For a quick quote, please phone 0345 464 0079 or email us.
Why Horncastle customers choose us
- We leave the area clean and tidy
- White, clear, grey or coloured to suit, where the product allows
- Domestic, commercial and hotel work
- 20+ years of sealant experience
Towns and villages near Horncastle
Other services in Horncastle
FAQs for Horncastle
Can you help a landlord with a rental near Reading West station?
Yes, landlords and agents are among the people we work for, and several properties can go on one quote. You can call 0345 464 0079 or send us an email with the details for a clear quote.
Is Horncastle in your area for external mastic?
Yes. We work across London and the South East, and Horncastle is part of that. Just call 0345 464 0079 or send us an email with a few details of the job, and we will send you a clear quote.
Is there any odour?
That depends on the sealant. Some products have a noticeable smell, others very little, and any smell fades as they cure.
How often do external joints need resealing?
That varies with the weather the wall faces, how much it moves and the sealant used. Treat it as a maintenance item and look at it yearly and reseal when it splits.
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. We use products from Arbo and Everbuild.
Do I have to be there?
That depends on where the joints are. For work indoors, someone needs to let us in, while outside work can sometimes be arranged differently.
Do you work at height?
That depends on the building and the joints. We work on joints that can be reached safely. Give us some details and we will confirm the access.
What should I tell you?
The location, the problem and the rough size of the job. If you can, email a few pictures.
What we do, step by step
On the day, there’s very little for you to do. Point us to the joints and we’ll get on with it. The work itself takes a few hours to a few days, depending on the length of joint and the access. A visit to Horncastle 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.
- First, the joints are inspected and the access agreed.
- We cut out the old mastic and rake out anything in the joint.
- Joint faces are cleaned back and primed if the sealant needs it.
- Backing rod sized to the joint goes in to set the depth.
- We apply the sealant, tool it and check the whole run.
How to prepare
- Clear items away from the joints we are working on
- Keep children and pets away from the work area
- Mention if the joints have been sealed before
How to get a quote
We quote each job on its own. Simply ring 0345 464 0079 or drop us an email and describe the job, and photos are welcome.
Read more
DIY versus a professional finish
A careful DIYer can reseal a simple joint, such as a straightforward joint indoors. The common mistakes are sealing over old sealant, sealing a damp joint and using far too much.
Too much sealant is as bad as too little. A thick, smeared bead looks untidy and doesn’t move well, and getting the depth right matters as much as the look.
Aftercare tips
So the new joints stay in good condition:
- Ask before painting over external sealant
- Avoid pressure-washing directly into sealant joints
- Keep movement joints as flexible joints, not mortar
- Walk round the building once a year and look at the joints
Keep the joints clear of soil, plants and climbing growth. Damp material against the sealant shortens its life.
An open movement joint lets rain into the wall every time it pours. That can lead to damp patches, staining and frost damage.
For landlords and businesses
Businesses can book us for washrooms, kitchens, offices and more. For commercial premises, we can talk through working times when we quote.
Letting agents often deal with us directly. Tell us the address, the job and how access works and we will quote.
What external mastic looks like in Horncastle
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. With historic houses such as Mapledurham House (about 2.8 miles north) nearby, there’s older building stock in the area around Horncastle as well as newer homes. Where a home is older, older brick and stone need a sealant that suits them, at the right joint depth.
Homes close to Church of St Michael include some older properties, and the joints between older walls, newer extensions and the roofline need a sealant that can move. If you look after a building such as Kennet Valley Primary School, its movement joints, gutters and trims need looking after like any other building’s. If you let a flat or house near Reading West station, split movement joints are easy to miss on a rental until damp shows inside.
Horncastle is about 2 miles west of Reading, in Reading. Wherever you are in the RG30 postcode area, we can carry out external mastic at your property. We cover 34 towns and villages across Reading.
All of RG30 and RG31 is within our area for external mastic, from the main roads to the quietest streets. Streets in the area include Low Lane, Usk Road and Mill Lane. Other places close to Horncastle include Fords Farm (1 mile south), Southcote (1 mile east), Tilehurst Within (1 mile north), Beansheaf Farm (1 mile south-west) and Burghfield Bridge (1 mile south). We also work in nearby towns such as Caversham (3 miles north-east), Shinfield (4 miles south-east), Arborfield Garrison (7 miles south-east), Caversham Heights (3 miles north-east), Whitley Wood (3 miles south-east) and Sonning Common (5 miles north). Being one of Reading’s larger places, Horncastle has every kind of property, from flats to offices.
Landmarks near Horncastle
Locally, jobs take us to homes and businesses close to Elvian School, Prospect School and Calcot Park. Horncastle’s nearest station is Reading West station, about 1.6 miles north-east. Nearby you’ll also find Battle Hospital (1.5 miles north-east) and Broad Street Mall (2.2 miles east). Not far away are Fobney Island Wetland Reserve and South Lake.
What the job involves on each surface
Joints between dissimilar materials
Joints where frames, sills or panels meet the wall are common leak points. We cut out the old sealant and reseal with a product suited to both surfaces.
Brickwork movement joints
Clay brickwork grows slightly over its life and moves with the weather. That movement goes into the joint, so the sealant in it must stay soft and stretchy.
What affects the cost of external mastic
We don’t publish a price list, because no two jobs are the same. What we look at:
- How easy the joints are to reach
- The old material and how stubborn it is
- How many rooms, windows or areas are involved
- Which sealant suits the joint
Homes and businesses are quoted the same way: the amount of work, how we reach it and what it needs. Ask us for a quote and we will go through it with you.
What we need to know
The more you tell us, the more accurate the quote. When you ask for a quote, tell us:
- Access, such as stairs, a lift or height
- How many joints, rooms or windows are involved
- Photos by email, if that is easy
- What’s wrong with the joints now
Asking for a quote is easy: let us know what needs doing and where and its rough size. A few pictures by email make the job easier to understand.