West Sussex · England
External Mastic in Birchgrove
External mastic in Birchgrove from a team with over 20 years’ experience. Rated 4.9 on Google from 180+ five-star reviews.
- Sealant pulling away from one side of the joint
- Movement joints with cracked, split or missing sealant
- Moss and dirt in joints with no sealant left
What affects the quote in Birchgrove
Every job gets its own quote. These are the things that affect it:
- How much there is to do
- When we can work, for business premises
- The old material and how stubborn it is
- Whether there’s mould to deal with
Rather than a set price list, we price the job in front of us: the amount of work, the old material and the access. The price is agreed before we begin.
Asking for a quote
Photos by email are helpful but not essential. Please mention:
- How many joints, rooms or windows are involved
- The problem you’ve noticed
- If someone has resealed it before
- The address or postcode of the job
Every job is quoted individually. Just phone 0345 464 0079 or drop us an email with the details.
How we handle external mastic in Birchgrove
External mastic is a job where short cuts show quickly. Overfilled joints, missing backing rod and sealant laid over old sealant all tend to fail early. We take the old material out and do it properly. We work on joints between brick and frames, concrete & block and brickwork movement joints, and people most often call us about joints pointed up with cement by mistake and gaps where render, brick and frames meet.
Outside joints can only be sealed when they’re dry, so work in Birchgrove is booked around the forecast. Let us know about access to every wall, plus any garages or outbuildings.
Whatever the size of the job, it’s backed by our 12-month guarantee in Birchgrove and across West Sussex.
- Location
- Birchgrove (RH17)
- Region
- West Sussex
- Guarantee
- One year on every job
- Quote
- Quoted before any work starts
- Telephone
- 0345 464 0079
- Page updated
- 26 October 2026
Should I try it myself first?
Sealing over old silicone is the commonest DIY error. Silicone doesn’t stick to old silicone, so it peels away and traps moisture behind it. All the old material has to come out first.
Some jobs are best left to a professional: high-level joints, fire-rated gaps, external movement joints and big jobs call for the right materials, safe access and experience.
What we do, step by step
At the end, we look at the finished work together. The visit itself normally takes a few hours for a handful of joints, longer for a whole elevation, depending on the amount of work. Somewhere like Birchgrove needs a little journey planning: tell us about narrow lanes, gates, long drives and where we can park. Everything for the job comes with us, so a second trip is avoided where possible.
- First we look over the joints with you, agree which to renew and talk through access.
- The old mastic and anything lodged in the joint is removed.
- We clean both faces of the joint and prime them where the product calls for it.
- Backing rod goes in next, setting the depth and keeping the sealant off the back of the joint.
- The new sealant, chosen to suit the brick or render, is applied and tooled to a neat finish.
Before we arrive
- Clear the area around the work
- Mention any sign-in or site rules at work premises
- Tell us about any previous sealing or DIY attempts
Getting a quote
For a quick quote, get us on the phone, or email us if that is easier. Tell us about the joints that need doing and we will explain what’s involved and give you a clear price.
Advice
How to look after the new joints
After the cure time, these simple habits help:
- Keep movement joints as flexible joints, not mortar
- Check external joints each spring
- Have failed joints looked at early
- Keep water from gutters off the wall
Keep pressure washers away from the sealant. A strong jet can damage the edges of the bead over time.
Act while the splits are small. At that stage it’s a simple cut out and reseal with no damage behind it to deal with.
Surface by surface
Render joints
The face of render can be soft, so a sealant that stretches easily protects the edges. Priming is done where the sealant calls for it.
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.
Nearby places to Birchgrove
Other services in Birchgrove
Birchgrove buildings and the weather
With historic houses such as Priest House (about 2.9 miles north-west) nearby, there’s older building stock in the area around Birchgrove as well as newer homes. In older buildings, older brick and stone need a sealant that suits them, at the right joint depth. The South East is one of the drier parts of the UK, but outside sealant still needs a dry, clean surface, so outdoor work is planned around the forecast.
In the older streets around Chelwood Gate Church, old and new materials meet at the roofline and walls, which is where sealant earns its keep.
Birchgrove is about 5 miles south of East Grinstead, in West Sussex. Jobs in Birchgrove get the same care as everywhere else we work: old sealant removed completely, careful preparation and a one-year guarantee. Birchgrove is one of 371 towns and villages in West Sussex where we work. You can also see our page for Crawley, about 9 miles away.
Work in RH17 is quoted and booked the same way as anywhere else. Other places close to Birchgrove include Chelwood Gate (1 mile east), Chelwood Common (1 mile south-east), Danehill (1 mile south), Horsted Keynes (2 miles south-west) and Wych Cross (2 miles north-east). Further out, we also cover Crawley (9 miles north-west), Horsham (14 miles west), Haywards Heath (5 miles south-west), Burgess Hill (8 miles south-west), East Grinstead (5 miles north) and Broadfield (9 miles west).
Near you in Birchgrove
A little further out are Heaven Farm Museum (2.3 miles south) and Waterbury Castle (1.7 miles south-west). The countryside around Birchgrove includes Brickfield Meadow.
Work for landlords, hotels and businesses
A neglected joint can let water reach the structure, which matters even more when someone else lives there. Keeping joints in good order is simple maintenance.
We work for letting agents and landlords as well as homeowners. Sealant work between tenants is a simple way to keep a property in good order.
Common questions in Birchgrove
What guarantee comes with external mastic in Birchgrove?
Every job comes with our one-year guarantee, wherever it is. We’re also fully insured and ARBOMaster approved.
Is Birchgrove within the area you cover?
Yes. Birchgrove is within the area we cover, which takes in towns, villages and rural addresses. We work across London and the South East. Just mention lanes, gates or anything else about the route when you book.
Do I have to be there?
If the work is inside, we need someone to let us in. After that, you can carry on with your day.
Why is there a gap in my brick wall?
It’s a deliberate gap that lets the wall expand and contract without cracking. It’s sealed with a flexible sealant, not mortar.
What information do you need?
The location, the problem and the rough size of the job. If you can, email a few photos.
Can you seal joints between two different materials?
Yes. The old joint is removed, both surfaces cleaned and primed where needed, and a flexible sealant applied. We pick a colour that works with both materials.
Is it worth trying it myself?
Some simple jobs can be done by a careful DIYer. The usual mistakes are sealing over old sealant, sealing a damp joint and using too much.
Do you work for landlords and businesses?
Yes. We work in homes, commercial premises and hotels.
Signs you need external mastic in Birchgrove
The wrong product in a moving joint is a classic cause. A stiff, general-purpose sealant can’t cope with a joint that moves a lot, so it pulls away from the edges.
Common reasons people contact us include:
- Hard, crazed mastic that has stopped moving
- Panel joints letting water in
- Plants rooting in failed movement joints
- Cracked joints where brick meets render or frames
Around Birchgrove, as everywhere, external mastic is only as good as the preparation behind it.
Before you book anyone
- How much experience the applicator has
- Whether they seal over old material or remove it
- How hidden problems are handled
- What the quote includes, VAT included or not