Hampshire · England
Gilbert Street External Mastic
Our applicators work in Gilbert Street on sealing brickwork movement joints, render, cladding and façade joints. Old sealant removed completely, joints prepared properly and every job guaranteed for a year.
- Old sealant gone brittle and cracked
- Joints where the bead has come unstuck
- Rigid filler in a joint that should flex
How we handle external mastic in Gilbert Street
We cut out failed sealant, set the joint depth with closed-cell backing rod and reseal with a low-modulus exterior sealant. The colour is chosen to suit the brick or render so the line blends in. We’re often asked to deal with old sealant gone brittle and cracked and cracked joints where brick meets render or frames, across façade panels, render & cladding joints and brickwork movement joints.
Outside joints can only be sealed when they’re dry, so work in Gilbert Street is booked around the forecast. Let us know about access to every wall, plus any garages or outbuildings.
Each job carries a 12-month guarantee.
- Where
- Gilbert Street (SO24)
- Wider area
- Hampshire
- Cover
- A year, on every job
- Quotes
- Quoted before any work starts
- Telephone
- 0345 464 0079
- Last updated
- 26 October 2026
Leave it or put it right?
Low-modulus sealants stretch easily, so they put less strain on the joint edges. That matters on brick, render and concrete, which can be weaker at the face. A stiffer product can damage the joint edge as it fails. Around Gilbert Street, older homes often have timber in their floors and frames, where water from a failed joint can cause rot if it’s left.
Rather than a set price list, we price the job in front of us: how many joints, what’s in them now and how we reach them. The price is agreed before we begin.
Why us?
- A choice of colours where the product allows
- More than 20 years in sealant work
- A sealant colour to suit the surroundings
- We agree the colour with you first
Read what affects the cost or what customers say.
What affects the quote in Gilbert Street
Call for a quick quote. The main things that affect it are:
- When we can work, for business premises
- The product the joint needs
- How many rooms, windows or areas are involved
- Whether there’s mould to deal with
What you pay reflects the work, not a rough estimate. That’s why we ask a few questions first.
What to tell us for a quote
Photos by email are helpful but not essential. Please mention:
- Any previous sealing or DIY work
- Photos by email, if that is easy
- If it’s domestic, commercial or a hotel
- Access, such as stairs, a lift or height
If you’re in Gilbert Street and need external mastic, ring 0345 464 0079 or email us. A short description of the job and where it is helps us quote, and we’ll agree the price before any work begins.
DIY versus a professional finish
The biggest DIY mistake is sealing over old sealant. Silicone does not stick to old silicone, so it lifts and traps water and mould underneath. Everything old must be removed first.
A DIY attempt doesn’t rule out a professional job. We remove it and do the joint properly, so tell us about it when you ask for a quote.
What we do, step by step
A visit follows a simple pattern: we check the joints, mask and protect the surrounding surfaces, carry out the job and clear up. Most jobs take a few hours to a few days, depending on the length of joint and the access. In a small place like Gilbert Street, access is usually the main thing to plan. If the job is outside, mention outbuildings, exposed walls and how to reach them.
- We inspect the joints and agree which need resealing and how they’ll be reached.
- The old mastic and anything lodged in the joint is removed.
- Both sides are cleaned back to sound material and primed if needed.
- We push in closed-cell backing rod so the sealant is the right depth and bonds to the sides only.
- A flexible exterior sealant is applied and tooled in a colour to suit the wall.
Getting ready for the visit
- Keep children and pets away from the work area
- Tell us about any water getting in
- For indoor joints, keep the area dry beforehand if you can
Ask for a quote
It all starts with a short chat. Describe the problem, the location and the size of the job, and we will explain how we’d tackle it. Whenever you’re ready, ring 0345 464 0079 or send us an email.
Related advice
Also near Gilbert Street
What else we do in Gilbert Street
External mastic in Gilbert Street: local notes
Compared with the north and west, the South East gets less rain, yet outdoor joints still have to be sealed dry, so jobs are booked with the weather in mind. Historic houses like Bentworth Hall (about 4.2 miles north) are a reminder that the area around Gilbert Street has older buildings as well as new. Where a home is older, older walls and rooflines need a sealant that moves with them and suits the material.
For an older house near a landmark such as Church of St Peter, the joints between older walls, newer extensions and the roofline need a sealant that can move.
Gilbert Street is about 6 miles south-west of Alton, in Hampshire. Whether you’re in the middle of Gilbert Street or further out, we cover external mastic for every kind of property, from flats and houses to offices and hotels. Gilbert Street is one of 683 towns and villages in Hampshire where we work for external mastic. Our Southampton page covers work nearby.
All of SO24 is within our area for external mastic. That includes homes and businesses on Andrew's Lane, Gilbert Street and Swelling Hill and the roads around them. Other places close to Gilbert Street include Ropley (1 mile south-west), Kitwood (1 mile north-east), North Street (1 mile north-west), Charlwood (1 mile south-east) and Ropley Dean (1 mile west). Further out, we also cover Basingstoke (12 miles north), Winchester (11 miles west), Eastleigh (15 miles south-west), Horndean (13 miles south), Alton (6 miles north-east) and Waterlooville (14 miles south).
Landmarks near Gilbert Street
Nearby you will also find Barton Castle (4.1 miles north-west) and Alton Community Hospital (4.8 miles north-east). The countryside around Gilbert Street includes Shutts Copse and Red Hill.
Questions from Gilbert Street
Is external mastic in Gilbert Street guaranteed?
All our work, in Gilbert Street and everywhere else, comes with a 12-month guarantee. We’re also fully insured and ARBOMaster approved.
Is Gilbert Street 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.
Where are you based?
Our base is Crawley, with over 20 years’ experience. We work across South East England, London and Scotland.
When will the joints need doing again?
It varies from wall to wall: sunny, exposed elevations and busy joints wear faster. Check them each year and reseal when they split or harden. Our work comes with a 12-month guarantee.
Can you reach joints on upper floors?
That depends on how high the joints are and the ground below. Low-level joints are straightforward; for higher ones, send details and we’ll confirm the access.
Will there be a smell?
That depends on the sealant. Some smell for a while, some hardly at all, and any smell fades as they cure.
What information do you need?
Where the job is, what the problem is and roughly how big it is. Photos by email help too.
Do I need to be at home?
If the work is inside, we need someone to let us in. After that, you can carry on with your day.
When to call us in Gilbert Street
Some movement joints have been pointed up with mortar, often by someone who didn’t know what it was for. The joint cannot move, so the wall cracks somewhere else instead.
Keep an eye out for any of the following:
- Panel joints letting water in
- Movement joints filled with mortar instead of sealant
- Old sealant gone brittle and cracked
- Plants rooting in failed movement joints
For site and facilities teams at buildings such as Ropley Church of England Primary School, larger buildings have long runs of movement joint that eventually need resealing.
Comparing quotes
- Whether you can choose the colour
- How hidden problems are handled
- What insurance they hold
- What the quote includes, VAT included or not
What the job involves on each surface
Render joints
Render has movement joints and stop beads that need sealing. We reseal them with a flexible exterior sealant that suits the render colour.
Cladding and façade panels
Panel systems often rely on sealant between and around the panels. We reseal them with a sealant suited to the panel material.
For landlords and businesses
We work for letting agents and landlords as well as homeowners. Resealing between tenancies is a simple way to keep a property in good order before the next move-in.
For anyone letting property in or around Gilbert Street, jobs at different addresses can be quoted together. Just tell us the addresses and what each one needs, and photos by email help.