Hertfordshire · England
Ayot St Peter External Mastic
Sealing brickwork movement joints, render, cladding and façade joints for Ayot St Peter, backed by a one-year guarantee. Ask us for a quote.
- Joints pointed up with cement by mistake
- Moss and dirt in joints with no sealant left
- Joints with sealant missing in places
External mastic in Ayot St Peter, done properly
Failed sealant is cut out, the depth set with closed-cell backing rod, and the joint resealed with a low-modulus sealant made for outside. The colour is chosen to suit the brick or render. If you have gaps where render, brick and frames meet and plants rooting in failed movement joints, we can put it right, whatever the surface.
Somewhere as small as Ayot St Peter, 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.
Big or small, it’s backed by our 12-month guarantee in Ayot St Peter and across Hertfordshire.
- Where
- Ayot St Peter (AL6)
- Region
- Hertfordshire
- Cover
- One year on every job
- Price
- Quoted before any work starts
- Telephone
- 0345 464 0079
- Updated
- 26 October 2026
FAQs for Ayot St Peter
Is Ayot St Peter within the area you cover?
Yes, Ayot St Peter is covered. Our work covers London and the South East, from towns to the smallest places. The journey is planned ahead, so it helps to know about access.
Can you help a landlord with a rental near Welwyn North station?
Yes, we work for letting agents and landlords. Just call 0345 464 0079 or drop us an email and tell us about the property, and we’ll give you a clear quote.
Are you an approved applicator?
Yes. We’re approved under the ARBOMaster scheme, the approved applicator scheme for Arbo sealants.
Where is Mr Mastic based?
Our base is Crawley. Our area covers South East England, London and Scotland.
Can I add another job to the visit?
Yes. Tell us about everything you’d like done.
Can you match the colour of my brickwork?
We choose a sealant colour to suit the brick, stone or render so the joint blends in. There’s a wide choice of exterior colours.
Should I point up the gap in my brickwork?
No, not if it’s a movement joint. Pointing it stops it working, and the wall may crack nearby. A flexible sealant is the right fill.
Do you use backing rod?
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 affects the quote in Ayot St Peter
There’s no set price list, because jobs vary so much. The quote depends on:
- The old material and how stubborn it is
- Any working-time requirements on site
- The size of the job
- How many areas need sealing
A failed joint rarely gets cheaper to fix by waiting. If you’re unsure, phone 0345 464 0079 or send us an email and we will give you an honest view and a quote.
What to tell us for a quote
Before you ask for a quote, have a think about:
- How we’d reach the joints
- Where the property is
- Roughly how big the job is
- The problem you’ve noticed
We quote each job on its own, so start by telling us what you need. Just call 0345 464 0079 or send us an email with the details.
What the job involves on each surface
Concrete and blockwork
Big joints in concrete need careful depth control. We size the backing rod to the gap so the sealant isn’t too deep.
Render joints
Rendered walls have joints at beads, openings and changes of material. We reseal them with a flexible exterior sealant that suits the render colour.
DIY sealant or a professional job?
A careful DIYer can reseal a simple joint, such as a straightforward joint indoors. The common mistakes are sealing over old sealant, sealing a damp joint and using far too much.
What a professional job adds is preparation and the right product. Joints are cleaned back to sound surfaces and dried, and the sealant is chosen for how the joint moves and where it is, and the work is guaranteed for a year.
What external mastic looks like in Ayot St Peter
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. With historic houses such as Shaw's Corner (about 1.4 miles north-west) nearby, there’s older building stock in the area around Ayot St Peter as well as newer homes. In older buildings, older walls and rooflines need a sealant that moves with them and suits the material.
Letting a property close to Welwyn North station? Then failed wall and movement joints let damp in, so they’re worth checking between tenancies. For an older house near a landmark such as Church of St Peter, old and new materials meet at the roofline and walls, which is where sealant earns its keep. For site and facilities teams at buildings such as Monk's Walk School, its movement joints, gutters and trims need looking after like any other building’s.
Ayot St Peter is about 3 miles north-west of Welwyn Garden City, in Hertfordshire. Our applicators cover external mastic for homes and businesses in Ayot St Peter. Ayot St Peter is one of 381 towns and villages in Hertfordshire we cover. For nearby work, see our London page.
Every address in AL6 is within our area for external mastic. We also cover the places around Ayot St Peter: Ayot Green (1 mile south-east), Welwyn (1 mile north-east), Ayot St Lawrence (1 mile north-west), Monkswood (2 miles east) and Codicote Bottom (2 miles north). Larger places within reach include Watford (13 miles south-west), Hemel Hempstead (11 miles south-west), Stevenage (6 miles north-east), St Albans (6 miles south-west), Welwyn Garden City (3 miles south-east) and Harpenden (5 miles west).
Landmarks near Ayot St Peter
Typical jobs here are in homes near Danesbury Park and The Red Lion pub. The closest station to Ayot St Peter is Welwyn North station, about 2 miles east of the centre. Nearby you’ll also find Howard Centre (2.2 miles south-east) and Datchworth Museum (3.9 miles north-east). Open spaces near Ayot St Peter include Stocking Springs Wood.
What we do, step by step
We keep the work tidy and contained to the joints we’re treating, so you can carry on as normal. The job usually takes a few hours to a few days, depending on the length of joint and the access, and we tell you how long to leave it before we go. Somewhere as small as Ayot St Peter, access is often the only tricky part. 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.
- The joint faces are cleaned and primed where the sealant needs it.
- Closed-cell backing rod is fitted to set the depth and stop three-sided bonding.
- We gun in a flexible exterior sealant in a colour that suits the wall and tool it neatly.
Getting ready for the visit
- Tell us about access, such as stairs, a lift or high-level joints
- Mention any leaks or damp you’ve noticed
- Where the joints are inside, avoid wetting them before we arrive
Getting a quote
For a quote, call 0345 464 0079 or email us and tell us where the job is and what the problem looks like. You will have a clear quote before any work starts.
Advice
Also near Ayot St Peter
More services for Ayot St Peter
Why deal with it now?
A properly done movement joint is an even line in a colour that suits the wall. A hurried job with smeared edges and no backing looks worse and fails sooner, so it pays to do it properly once. Older cottages and farmhouses around Ayot St Peter can have timber floors and frames, where water from a failed joint can cause rot if it’s left.
A few things move the cost up or down: the old material and how easily it comes out, any mould to treat, and whether we need extra access for height. We take all of that into account in your quote.
Why Ayot St Peter customers choose us
- Old sealant always removed completely
- ARBOMaster approved applicator
- Domestic, commercial and hotel work
- Sanitary silicone with an anti-fungal additive in wet areas
Read what affects the cost and our reviews.
Landlord and commercial work in Ayot St Peter
Businesses can book us for washrooms, kitchens, offices and more. On commercial sites, working times can be discussed when we quote.
Failed sealant is one of the commonest items on a check-out report, and it’s quick to put right between tenancies. Several properties can go on one quote.
Looking after it afterwards
Aftercare is simple, and it makes a real difference:
- Show decorators and builders where the movement joints are
- Ask before painting over external sealant
- Act on the first splits you see
- Deal with leaking gutters that soak the joints below
Avoid pressure-washing straight into the joints. A strong jet can damage the edges of the bead and let water in behind.
Act while the splits are small. Then it’s a straightforward cut-out and reseal before water has had years to get in.