Scottish Borders · Scotland
External Mastic in Greenlaw
Sealing brickwork movement joints, render, cladding and façade joints for Greenlaw, backed by a 12-month guarantee. Ask us for a quote.
- Weeds or debris growing in open joints
- Joints pointed up with cement by mistake
- Joints where the bead has come unstuck
Keeping the joints in good condition
No joint lasts for ever, but care makes a real difference. Our tips:
- Wash walls gently around the sealant
- Point out the joints to other trades
- Never let anyone fill a movement joint with mortar
- Clear growth from the base of walls and joints
Keep pressure washers away from the sealant. High-pressure water can lift the edges and let water in behind.
Small splits are the time to act. At that stage it’s a simple cut out and reseal with no damage behind it to deal with.
How we handle external mastic in Greenlaw
On houses, flats and commercial buildings across Greenlaw, we reseal joints in brickwork, render, cladding and façade panels. The preparation is the same whatever the wall: clean joint faces and the right depth. We are often asked to deal with failed sealant between panels on a façade and gaps where render, brick and frames meet, on render & cladding joints, copings & trims and brickwork movement joints.
Stone walls need a stone-friendly sealant, as acetoxy products can attack some stone. Newer houses need their movement joints and roofline trims kept sound.
All our work comes with a one-year guarantee.
- Location
- Greenlaw (TD10)
- Region
- Scottish Borders
- Cover
- A year, on every job
- Price
- A clear price before work begins
- info@mrmastic.co.uk
- Updated
- 26 October 2026
When it isn’t the sealant
We will always be straight with you, so here’s what new sealant won’t do:
- Rising or penetrating damp from elsewhere in the wall
- Walls that need new movement joints cut into them
- Structural movement, which needs a surveyor or engineer
Not sure which it is? You can send an email to info@mrmastic.co.uk and we’ll tell you honestly before you book.
Surfaces we seal
- Brickwork movement joints
- Joints between brick and frames
- Concrete & block
- Render & cladding joints
- Copings & trims
- Façade panels
FAQs for Greenlaw
Is there a guarantee on external mastic in Greenlaw?
All our work, in Greenlaw and everywhere else, comes with a 12-month guarantee. We’re also fully insured and ARBOMaster approved.
Do you cover Greenlaw for external mastic?
Yes, Greenlaw is within the area we cover. Our work covers the whole of Scotland. You can email us at info@mrmastic.co.uk and let us know what needs doing, and we will give you a clear price.
Why do you put foam in the joint first?
Backing rod controls the sealant depth and keeps it off the back of the joint. That way it bonds to the two sides only and can stretch.
What is a movement joint?
Brickwork, render and cladding all move a little, so long walls have planned gaps to take that movement. The gap is sealed with a flexible sealant over backing rod.
How much does external mastic cost in Greenlaw?
It depends on the job, so we quote each one individually. To get one, email us at info@mrmastic.co.uk with a short description of the job.
What information do you need?
Let us know what needs doing and where, plus pictures if you have them. We’ll ask anything else we need to know.
Can you seal over the old sealant?
No. Fresh sealant doesn’t stick to old sealant, and it traps any mould or water underneath. We remove it all first.
Do I have to be there?
That depends on where the joints are. Inside work needs someone to give us access, and for outside work we’ll agree access with you when we book.
What the job involves on each surface
Joints between dissimilar materials
Each side of the joint may need its own preparation. We prepare both faces so the sealant bonds properly.
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.
Towns and villages near Greenlaw
Also in Greenlaw
Work for landlords, hotels and businesses
From a single let to a portfolio, you get the same standard of work: old sealant fully removed, joints prepared properly and a 12-month guarantee.
A neglected joint can let water reach the structure, which is a bigger problem in a rented property. Resealing at the right time is simple maintenance that we can handle for you.
What happens on the day
The work is kept neat and contained to the joints we are treating, so you can carry on as normal. Expect the work to take anything from a few hours to several days, depending on the building, and we tell you how long to leave it before we go. In smaller Scottish places, parking is generally less of an issue than access and distance. Tell us how to find the property and how to reach the work, and the visit is planned around that.
- We look at every joint and agree a colour to suit the wall.
- Failed sealant is removed back to clean, sound faces.
- Closed-cell backing rod is pushed in so the sealant bonds to two sides only.
- 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
- Move anything stored near the joints
- Mention any tricky access
- Tell us about any water getting in
Getting a quote
Getting a quote is simple: let us know the job and the location and its rough size. Photos by email help us understand the job.
Read more
Greenlaw buildings and the weather
Plenty of Scottish homes have harled walls, and joints where harling meets other materials need a sealant that can grip and flex. Under the Repairing Standard, private landlords in Scotland have to keep homes wind and watertight, and sound outside sealant is part of that.
Homes close to Greenlaw Parish Church include some older properties, and older walls, gutters and the joints where extensions meet them need a flexible sealant.
Greenlaw is about 15 miles north-east of Galashiels, in the Scottish Borders. Homes, rented property, offices and hotels in Greenlaw can book us for external mastic. Every job comes with our one-year guarantee. Greenlaw is one of 89 towns and villages in the Scottish Borders where we work. Our Edinburgh page covers work nearby, about 33 miles away.
Our applicators cover all of the TD10 postcode area for external mastic. If you need external mastic at a property on The Square, East High Street and West High Street or anywhere close by, we can help. Nearby, we also carry out external mastic in Eccles (4 miles south-east), Gordon (4 miles south-west), Stichill (5 miles south), Gavinton (5 miles north-east) and Westruther (5 miles north-west). Further out, we also cover Galashiels (15 miles south-west), Kelso (7 miles south), Duns (7 miles north-east), Melrose (13 miles south-west), Earlston (10 miles south-west) and Lauder (11 miles west).
Local landmarks in Greenlaw
Typical jobs here are in homes near Cross Keys pub, among other places. Well-known places in the area include Hume Castle (2.9 miles south). For a walk, there’s Hule Moss.
DIY sealant or a professional job?
If you’ve already had a go yourself, that’s fine. We cut it out and start again.
The biggest DIY mistake is sealing over old sealant. Silicone doesn’t stick to old silicone, so it lifts and traps water and mould underneath. Everything old must be removed first.
When to call us in Greenlaw
Some movement joints have been pointed up with mortar by mistake. With the joint locked solid, the movement turns into cracks elsewhere in the wall.
Most people get in touch when they notice one of these:
- Cracked joints where brick meets render or frames
- Old sealant gone brittle and cracked
- Leaking joints around cladding and façade panels
- Joints with sealant missing in places
In and around Greenlaw, as anywhere, good external mastic starts with a clean, dry, properly prepared joint.
Before booking anyone
- Which sealant they’ll use, and why
- Whether they’re fully insured
- The length of the guarantee
- How the surfaces are prepared before sealing