Hertfordshire · England
Graveley External Mastic
Movement joints in Graveley need attention? We cut out the old, prepare the joints and apply the right sealant, and the work is guaranteed for a year.
- Sealant pulling away from one side of the joint
- Moss and dirt in joints with no sealant left
- Rain getting behind render or cladding at a joint
Questions from Graveley
Will you come out to Graveley?
Yes, Graveley is covered. We work across London and the South East, from towns to the smallest places. Longer journeys are simply planned in advance.
Is Graveley in your area for external mastic?
Yes. We work across London and the South East, and Graveley is part of that. You can phone 0345 464 0079 or drop us an email and let us know what needs doing.
Do you guarantee your work?
Yes. Every job comes with a one-year guarantee.
What is backing rod for?
We fit closed-cell backing rod wherever the joint depth needs controlling. It controls the depth and stops the sealant bonding to the back.
I’m a tenant. Can you help?
Yes, but check with your landlord or agent first. Landlords are often happy for the work to be arranged.
Do you do commercial work?
Yes. Larger jobs can be planned room by room or area by area.
How long should I leave it?
Different products cure at different speeds, so follow the cure time we give you.
Do you take out the old sealant first?
Yes, every time. New silicone does not stick to old silicone, so any old material comes out before anything new goes in.
About our external mastic in Graveley
Joints between dissimilar materials, like brick against render or concrete against a steel frame, see movement from both sides. A flexible exterior sealant takes up that movement where a rigid filler would soon crack. We work on copings & trims, render & cladding joints and brickwork movement joints, and people most often call us about moss and dirt in joints with no sealant left and failed seals between different materials.
In a village or hamlet like Graveley, older cottages and farm buildings often stand in the open, so walls and rooflines take the full force of wind and rain. Joints on those walls need a sealant that moves with the building and stays in place.
Every job comes with our one-year guarantee.
- Location
- Graveley (SG4)
- Wider area
- Hertfordshire
- Guarantee
- One year on every job
- Quotes
- A clear price before work begins
- Phone
- 0345 464 0079
- Page updated
- 26 October 2026
External mastic in Graveley: local notes
The South East is one of the drier parts of the UK, though outdoor sealant still has to go onto a dry joint, so the forecast decides the day. Historic houses like Knebworth House (about 4.4 miles south) are a reminder that the area around Graveley has older buildings as well as new. Where a home is older, older brick and stone need a sealant that suits them, at the right joint depth.
In the older streets around Church of St Mary, the joints between older walls, newer extensions and the roofline need a sealant that can move. If you look after a building such as Graveley Primary School, larger buildings have long runs of movement joint that eventually need resealing. Letting a property close to Stevenage station? Then split movement joints are easy to miss on a rental until damp shows inside.
Graveley is about 2 miles north-west of Stevenage, in Hertfordshire. For external mastic in and around Graveley, it’s easy to get a quote: please phone 0345 464 0079 or send us an email. We cover Hertfordshire from our Crawley base, Graveley included. We cover 381 towns and villages across Hertfordshire, large and small. You can also see our page for London, about 31 miles away.
Work in SG4 is quoted and booked the same way as anywhere else. Whether your property is on High Street, Oak Lane and Ashwell Close or a nearby road, we can help. Neighbouring places we cover for external mastic include Todd's Green (1 mile south-west), Great Wymondley (1 mile north-west), Little Wymondley (1 mile west), Titmore Green (1 mile south-west) and Lower Titmore Green (1 mile south-west). Larger places within reach include St Albans (14 miles south), Welwyn Garden City (10 miles south), Harpenden (10 miles south-west), Hitchin (3 miles west), Hoddesdon (15 miles south-east) and Hatfield (12 miles south).
Local landmarks in Graveley
Typical jobs here are in homes near Waggon And Horses Public House, Church of Saint Nicholas and The John Henry Newman School and the streets around them. Graveley’s nearest station is Stevenage station, roughly 2.4 miles south. Other landmarks nearby include Wymondley Castle (1.1 miles west) and Stevenage Museum (2.4 miles south). Open spaces near Graveley include Purwell Ninesprings.
Quotes for external mastic in Graveley
We don’t publish a price list, because jobs vary so much. The quote depends on:
- Whether the work is at height
- The number and length of the joints
- Which sealant suits the joint
- Whether old sealant or filler has to be cut out
Instead of a standard rate, we price the job in front of us: the amount of work, the old material and the access. You will know the price before we begin.
Helping us quote
You don’t need to know the technical terms. It helps if you can tell us:
- Where the property is
- If it’s domestic, commercial or a hotel
- How many joints, rooms or windows are involved
- What’s wrong with the joints now
For a quick quote, get us on the phone, or send an email if you’d rather. Tell us about the joints that need doing and we’ll talk you through the work and give you a clear quote.
DIY versus a professional finish
The biggest DIY mistake is sealing over old sealant. Silicone does not stick to old silicone, so it peels away and traps moisture behind it. Everything old must be removed first.
What a professional job adds is preparation and the right product. We take joints back to clean, dry surfaces, and the sealant is matched to the joint and its conditions, then guaranteed for a year.
For landlords and businesses
Businesses can book us for washrooms, kitchens, offices and more. On commercial sites, working times can be discussed when we quote.
From a single let to a portfolio, you get the same standard of work: the old material taken out, careful preparation and a 12-month guarantee.
What the job involves on each surface
Copings and trims
Metal and stone copings both move with temperature, so the joints need a sealant that stays flexible year round.
Concrete and blockwork
The face of concrete or block is often dusty, so preparation is key. A primer goes on where the product requires one.
Why act early in Graveley
Resealing a run of joints in one go is usually better than patching one at a time. Joints of the same age tend to fail together and it means sorting access once. In a small place like Graveley, homes can be exposed to wind and rain, which finds any gap, and damp in older walls is slow to dry out.
There are no prices on our website, because the cost depends so much on the job itself. For a quick quote, please call 0345 464 0079 or drop us an email and we will talk you through it.
What you get with us
- Colour picked to suit the job
- Colour agreed with you before work begins
- Any old sealant cut out fully, not covered over
- ARBOMaster approved applicator
Read how sealant jobs are priced or our reviews.
Nearby places to Graveley
Also in Graveley
What we do, step by step
Good joint work is mostly preparation, and we do not rush it. Joints are cleaned back and dried before anything new goes in. In total, it usually takes a few hours to a few days, depending on the length of joint and the access. In a small place like Graveley, access is normally the main thing to plan. For outside work, also let us know about exposed walls and any outbuildings involved.
- We start by checking each joint, agreeing the ones to redo and how we will reach them.
- Old sealant and any debris are cut and raked out.
- 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
- On commercial sites, let us know about site rules
- Let us know about parking restrictions
- Mention any leaks or damp you’ve noticed
How to get a quote
There’s no standard price list, because every job is different. Instead, we give you a clear price for your job. To arrange one, ring 0345 464 0079 or drop us an email.
Read more
What sealant work cannot fix
Sealant is not the answer to every problem, and we’ll tell you before we start. Sealant will not put right:
- Cutting new joints into brickwork, which is building work rather than sealant work
- Cracks in the bricks or render themselves, away from the joints
- Structural movement, which needs a surveyor or engineer
If you’re not sure, just call 0345 464 0079 or email us and we will give you a straight answer before you book.
Where we work in Graveley
- Brickwork movement joints
- Copings & trims
- Façade panels
- Concrete & block
- Render & cladding joints
- Joints between brick and frames