Hertfordshire · England
Roe Green External Mastic
Sealing brickwork movement joints, render, cladding and façade joints in Roe Green, with a 12-month guarantee on every job. Call for a quick quote.
- Joints pointed up with cement by mistake
- Damp patches traced to an open external joint
- Movement joints with cracked, split or missing sealant
How we handle external mastic in Roe Green
External mastic is a job where short cuts show quickly. New sealant over old, joints packed with mortar and beads with no backing all tend to fail early. We take the old material out and do it properly. We are often asked to deal with panel joints letting water in and old sealant gone brittle and cracked, across façade panels, copings & trims and render & cladding joints.
Somewhere as small as Roe Green, homes and farm buildings often face open ground, where walls and rooflines take the weather head on. Gutter joints and wall joints there need a sealant that can flex and stay put.
The work is covered for a year after we finish. If anything isn’t right with it, phone 0345 464 0079 or email us.
- Place
- Roe Green (SG9)
- Wider area
- Hertfordshire
- Cover
- One year on every job
- Price
- A clear price before we start
- Telephone
- 0345 464 0079
- Updated
- 26 October 2026
Roe Green buildings and the weather
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.
Letting a property close to Ashwell & Morden station? Then failed wall and movement joints let damp in, so they’re worth checking between tenancies. Managing a site like Sandon Junior Mixed and Infant School? Then larger buildings have long runs of movement joint that eventually need resealing.
Roe Green is in Hertfordshire. For external mastic in and around Roe Green, it’s easy to get a quote: please phone 0345 464 0079 or drop us an email. We cover Hertfordshire from our Crawley base. Roe Green is one of 381 places in Hertfordshire we cover for external mastic. There’s also a page for Chelmsford, roughly 30 miles from Roe Green.
Here we cover the SG9 postcode area for external mastic. Neighbouring places we cover for external mastic include Sandon (1 mile north-east), Green End (1 mile east), Rushden (1 mile south-west), Buckland (3 miles east) and Chipping (3 miles south-east). Within a short drive, we also cover Stevenage (7 miles south-west), Bishop's Stortford (13 miles south-east), Welwyn Garden City (14 miles south), Hitchin (8 miles west), Hertford (13 miles south) and Letchworth (6 miles west).
Local landmarks in Roe Green
Roe Green’s nearest station is Ashwell & Morden station, about 3.2 miles north. Other landmarks nearby include Clothall Castle (3.1 miles south-west). Not far away are Hawkins Wood.
What we are called out for in Roe Green
The wrong product in a moving joint is a classic cause. A high-modulus or general-purpose sealant can be too rigid for a busy joint, and it tears off the sides.
Most people get in touch when they notice something like this:
- Leaking joints around cladding and façade panels
- Cracked joints where brick meets render or frames
- Sealant that has lost its bond to the brick or render
- Rigid filler in a joint that should flex
If you live in an older home near Church of All Saints, older walls, gutters and the joints where extensions meet them need a flexible sealant.
Comparing quotes
- Are they insured?
- Is the old sealant removed completely?
- What the quote includes, VAT included or not
- What happens if they find a problem under the old sealant
What sealant work can’t fix
We’ll always be straight with you, so here’s what sealant can’t fix:
- Loose or hollow render, which needs re-rendering
- Adding movement joints to masonry that has none
- Cracked brickwork or render that needs a builder or plasterer
If in doubt, phone 0345 464 0079 or email us and we will say what we think.
What we seal
- Façade panels
- Joints between brick and frames
- Concrete & block
- Copings & trims
- Render & cladding joints
- Brickwork movement joints
The process
We keep the work tidy and contained to the joints we’re treating, so you can carry on as normal. The job generally takes anything from a few hours to several days, depending on the building, and we explain the cure time before we leave. In a small place like Roe Green, access is normally the main thing to plan. If the job is outside, mention outbuildings, exposed walls and how to reach them.
- 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.
Preparing for the visit
- Let us know if you’ve seen damp or leaks
- Let us know about parking restrictions
- Move anything stored near the joints
Getting a quote
Quotes start with a quick conversation. Tell us what’s wrong, where it is and how much there is, and we’ll talk you through what we’d do. Whenever you are ready, ring 0345 464 0079 or drop us an email.
Read more
DIY sealant or a professional job?
A DIY attempt does not rule out a professional job. We remove it and do the joint properly, so just mention it when you contact us.
What a professional job adds is preparation and the right product. We take joints back to clean, dry surfaces, and the sealant is chosen for how the joint moves and where it is, then guaranteed for a year.
FAQs for Roe Green
Can you do external mastic in Roe Green?
Yes. Our work covers London and the South East, and Roe Green is part of that. You can ring 0345 464 0079 or send us an email and let us know what needs doing, and we will send you a clear quote.
Do you work for landlords with property near Ashwell & Morden station?
Yes, we work for landlords and agents. Just phone 0345 464 0079 or send us an email and tell us about the property, and we’ll give you a clear price.
What do you put in the joint?
The product depends on the job: sanitary silicone where it gets wet, and sealants suited to movement or weather elsewhere. We use products from Arbo and Everbuild.
Will the new joint stand out?
We choose a sealant colour to suit the brick, stone or render so the joint blends in. Exterior sealants come in a good range of colours.
Is it OK to seal over old sealant?
No. We remove every bit of old sealant first.
Is it worth trying it myself?
It depends on the job. Work at height, movement joints, fire-rated gaps and large areas are best left to a professional, while a short indoor joint may be within reach.
How long should I leave it?
Cure times vary by product. Before we leave, we’ll tell you the cure time.
Do you use backing rod?
We fit closed-cell backing rod wherever the joint depth needs controlling. It controls the depth and stops the sealant bonding to the back, so the joint can move.
What affects the cost of external mastic
Your quote is based on your job. We take into account:
- Working hours on commercial sites
- How many rooms, windows or areas are involved
- The product the joint needs
- Any mould that needs treating
What you pay reflects the work, not a rough estimate. That is why we ask about the job first and send you a clear quote before any work starts.
What we need to know
The more you tell us, the more accurate the quote. When you ask for a quote, tell us:
- Photos by email, if that is easy
- Whether it has been sealed before
- The type of property
- Where the property is
Need a quote? Please ring 0345 464 0079 or send us an email with a few details. We’ll explain what we’d do and give you a clear price before any work starts.
Keeping the joints in good condition
To keep the joints looking good and working properly:
- Deal with leaking gutters that soak the joints below
- Look over the joints every year, ideally after winter
- Show decorators and builders where the movement joints are
- Avoid pressure-washing directly into sealant joints
Have a quick look at the joints each spring. Splits, gaps at the edges or plants in the joint are early warning signs.
Leave a failed movement joint and water keeps getting into the wall. That can lead to damp patches, staining and frost damage.
More services for Roe Green
Surface by surface
Render joints
Cracks along render joints let water in behind the coat. Resealing the joints early keeps water out.
Cladding and façade panels
Cladding and façade panels are usually separated by sealed joints. Each joint gets a sealant that suits the panel and its movement.