Reading · England
Trench Green External Mastic
External mastic for Trench Green and the surrounding area: the right sealant, proper preparation and a neat finish. Call for a quick quote.
- Joints where the bead has come unstuck
- Old sealant gone brittle and cracked
- Failed sealant between panels on a façade
Your questions about external mastic in Trench Green
Do you work for landlords with property near Tilehurst station?
Yes, we work for landlords and agents. Just phone 0345 464 0079 or email us and tell us about the property, and we’ll give you a clear price.
Is Trench Green within the area you cover?
Yes, smaller places are covered as well as towns. Our work covers London and the South East. Just mention lanes, gates or anything else about the route when you book.
How long will you be here?
A typical job takes a few hours to a few days, depending on the length of joint and the access. Your quote will say how long we expect yours to take.
Can I add another job to the visit?
Yes, we can. Several rooms, windows or areas can go on one quote.
Do I have to be there?
We need access to the joints, so we will agree that with you when we book. Indoors, that usually means someone at home.
Is it messy?
Very little: the area around the joints is protected first, and we tidy up before we go.
Can a movement joint be filled with mortar?
No. A mortar-filled joint can’t move, so the movement cracks the wall elsewhere. It needs a flexible sealant over backing rod.
Do you hold any approvals?
Yes. Mr Mastic is an ARBOMaster approved applicator, and we are fully insured.
External mastic in Trench Green, done properly
We are ARBOMaster approved applicators, and each external joint gets a sealant suited to it. Porous or awkward surfaces are primed where the sealant needs it and we use one wherever it does. We work on copings & trims, brickwork movement joints and joints between brick and frames, and common reasons people get in touch are joints with sealant missing in places and failed sealant between panels on a façade.
External sealant needs dry, clean surfaces, so work around Trench Green is planned for dry weather. Let us know about access to every wall, plus any garages or outbuildings.
We guarantee the work for a year. If there’s a problem with our work within the year, let us know and we’ll sort it.
- Place
- Trench Green (RG4)
- Wider area
- Reading
- Cover
- One year on every job
- Price
- A clear quote up front
- Phone
- 0345 464 0079
- Updated
- 26 October 2026
Different surfaces, different methods
Brickwork movement joints
Brick moves with heat and moisture, and grows a little over time. That movement goes into the joint, so the sealant in it must stay soft and stretchy.
Copings and trims
Joints in copings, parapets and trims are exposed to the worst of the weather. Each is resealed with a weatherproof, flexible sealant.
How the visit works
Most of a good job is in the preparation, so that’s where we spend the time. Every joint is cleaned and dried before new material goes in. All told, the work takes a few hours for a handful of joints, longer for a whole elevation. Somewhere as small as Trench Green, access is often the only tricky part. For outside work, also let us know about exposed walls and any outbuildings involved.
- Each joint is checked and the colour of the new sealant agreed.
- We take out the old sealant until the faces are sound.
- Backing rod goes in so the sealant can stretch between the two faces.
- Primer is applied wherever the sealant needs it.
- A low-modulus exterior sealant is gunned in and tooled to a neat finish.
Before we arrive
- For indoor joints, keep the area dry beforehand if you can
- Let us know about stairs, lifts or work at height
- Let us know about parking restrictions
Get a quote
Need a quote? Please ring 0345 464 0079 or email us and tell us about the job. We’ll explain what we’d do and give you a clear quote before any work starts.
Related advice
External mastic in Trench Green: local notes
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. With historic houses such as Mapledurham House (about 1.1 miles south-west) nearby, there’s older building stock in the area around Trench Green as well as newer homes. Where a home is older, older walls and rooflines need a sealant that moves with them and suits the material.
For landlords with property near Tilehurst station, outside joints that have cracked can let damp into a rental, so check them between lets.
Trench Green is about 2 miles north-west of Caversham, in Reading. Every kind of property in Trench Green is covered for external mastic. Every job comes with our one-year guarantee. We cover 34 towns and villages across Reading, from the larger towns to small villages.
All of RG4 is covered for external mastic. Close by, we work in Chazey Heath (1 mile east), Mapledurham (1 mile south-west), Purley on Thames (2 miles south-west), Norcot (2 miles south) and Tilehurst (2 miles south). Further out, we also cover West Reading (3 miles south), Shinfield (7 miles south-east), Arborfield Garrison (9 miles south-east), Horncastle (3 miles south), Whitley Wood (6 miles south-east) and Fords Farm (4 miles south).
What’s near Trench Green
Locally, jobs take us to homes and businesses close to Pack Horse Public House, among other places. Trench Green’s nearest station is Tilehurst station, about 1.7 miles south of the centre. Nearby you will also find Royal Berkshire Regiment Museum (2.6 miles south) and Battle Hospital (2.6 miles south). Not far away are Moor Copse Nature Reserve and Sonning Hill.
Common problems we fix in Trench Green
Some movement joints have been pointed up with mortar, often by someone who didn’t know what it was for. With the joint locked solid, the movement turns into cracks elsewhere in the wall.
Signs it’s time to call us include:
- Joints with sealant missing in places
- Failed seals between different materials
- Sealant that has lost its bond to the brick or render
- Hard, crazed mastic that has stopped moving
Homes close to Church of St Margaret and Bardolf Aisle include some older properties, and the joints between older walls, newer extensions and the roofline need a sealant that can move.
Comparing quotes
- Who does the work, and how experienced they are
- How long the guarantee is
- Is the old sealant removed completely?
- Are they insured?
How to look after the new joints
After the cure time, these simple habits help:
- Don’t let climbing plants root in the sealant
- Look over the joints every year, ideally after winter
- Show decorators and builders where the movement joints are
- Deal with leaking gutters that soak the joints below
Have a quick look at the joints each spring. Watch for splits, edges coming away or growth in the joint.
Water getting behind cladding or render can go unnoticed for a long time. When it finally shows inside, the joint may have been open for years.
For landlords and businesses
Mouldy or split sealant often shows up at the end of a tenancy, and it’s easy to sort out between tenants. Several properties can go on one quote.
Water getting past a failed joint can damage the building, which matters even more when someone else lives there. Resealing at the right time is simple maintenance that we can handle for you.
What we cannot put right
To be straight with you, there are a few things sealant won’t fix:
- Render that’s blown, hollow or coming away
- Damp from another source, such as a leaking gutter or a bridged damp-proof course
- Subsidence or other structural problems
Not sure which it is? You can ring 0345 464 0079 or send us an email and we’ll tell you honestly before booking.
Where we work in Trench Green
- Copings & trims
- Joints between brick and frames
- Concrete & block
- Façade panels
- Brickwork movement joints
- Render & cladding joints
Also near Trench Green
Other services in Trench Green
Why deal with it now?
The longer a joint stays open, the more water the wall takes in. Wet masonry is more easily damaged by frost, so the problem grows beyond the joint itself. Older cottages and farmhouses around Trench Green can have timber floors and frames, and water through a failed joint can rot timber if it’s left.
What you pay reflects the work, not a rough estimate. That is why we ask about the job first and agree the price before starting.
Why us?
- Approved under the ARBOMaster scheme
- Anti-fungal sanitary silicone in wet areas
- A 12-month guarantee on all work
- Sealant colour chosen to suit
Read our cost guide or customer reviews.