Hertfordshire · England
External Mastic in Clapgate
External mastic for Clapgate and the surrounding area: the right sealant, proper preparation and a neat finish. Call for a quick quote.
- Failed seals between different materials
- Rain getting behind render or cladding at a joint
- Leaking joints around cladding and façade panels
How we handle external mastic in Clapgate
Many failed façade joints only get noticed once there’s a stain or a damp patch inside. We inspect them, agree which need doing and reseal with a weatherproof, flexible sealant in a colour to suit. Common call-outs are for sealant that has lost its bond to the brick or render and movement joints filled with mortar instead of sealant, across render & cladding joints, brickwork movement joints and façade panels.
In a village or hamlet like Clapgate, older cottages and farm buildings often stand in the open, where walls and rooflines take the weather head on. Joints on those walls need a sealant that moves with the building and stays in place.
Your job is guaranteed for a year, as with all our work.
- Place
- Clapgate (SG11)
- Region
- Hertfordshire
- Cover
- One year on every job
- Quote
- A clear quote up front
- Phone
- 0345 464 0079
- Updated
- 26 October 2026
What we do, step by step
Every visit runs the same way: we look at the joints together, protect the area around them, carry out the job and clear up. It usually takes anything from a few hours to several days, depending on the building. In a small place like Clapgate, access is generally the main thing to plan. For outside work, also let us know about exposed walls and any outbuildings involved.
- We look at every joint and agree a colour to suit the wall.
- We take out the old sealant until the faces are sound.
- 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.
How to prepare
- Plan for the work area to be out of bounds to pets and children
- Where the joints are inside, avoid wetting them before we arrive
- Tell us if parking is tricky
Getting a quote
A good description makes for an accurate quote. Tell us where the job is, what’s wrong and how much there is.
Related advice
External mastic in Clapgate: local notes
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. Historic houses like Much Hadham Palace (about 3.4 miles south) are a reminder that the area around Clapgate has older buildings as well as new. In older buildings, older brick and stone need a sealant that suits them, at the right joint depth.
If you let a flat or house near Bishops Stortford station, failed wall and movement joints let damp in, so they’re worth checking between tenancies. For site and facilities teams at buildings such as Albury Church of England Voluntary Aided Primary School, its movement joints, gutters and trims need looking after like any other building’s.
Clapgate is about 4 miles north-west of Bishop's Stortford, in Hertfordshire. If you need external mastic in Clapgate, it’s easy to get a quote: please phone 0345 464 0079 or email us. We cover Hertfordshire from our Crawley base, Clapgate included. Clapgate is one of 381 towns and villages in Hertfordshire we cover. Our Chelmsford page covers work nearby (20 miles or so).
We cover every part of SG11 for external mastic. Close by, we work in Gravesend (1 mile north-west), Albury (1 mile north-west), Furneux Pelham (2 miles north), Braughing (3 miles west) and Hay Street (3 miles west). Larger places within reach include Stevenage (12 miles west), Bishop's Stortford (4 miles south-east), Welwyn Garden City (14 miles south-west), Hoddesdon (11 miles south-west), Cheshunt (15 miles south-west) and Hertford (11 miles south-west).
Local landmarks in Clapgate
Around Clapgate, our work takes us to homes and buildings near The Catherine Wheel pub, among other places. Clapgate’s nearest station is Bishops Stortford station, about 3.9 miles south-east of the centre. Other landmarks nearby include Moated mound (1.2 miles south-east) and Herts and Essex Hospital (4.2 miles south-east). The countryside around Clapgate includes Rushy Mead.
What affects the quote in Clapgate
For a quick quote, just ask. The main things that affect it are:
- The old material and how stubborn it is
- How many rooms, windows or areas are involved
- The size of the job
- How easy the joints are to reach
A failed joint rarely gets cheaper to fix by waiting, because water and mould keep working on it. If you are not sure whether it needs doing, ring 0345 464 0079 or email us for an honest opinion and a quote.
What we need to know
There’s no need for technical detail. Just tell us:
- A few pictures by email, if you can
- Roughly how big the job is
- What’s wrong with the joints now
- The type of property
For a quick quote, get us on the phone, or send an email if you’d rather. Describe what needs sealing and we will talk you through the work.
Why it’s worth doing now in Clapgate
The longer a joint stays open, the more water the wall takes in. In cold weather, frost can damage wet brick and render near the open joint, so the problem grows beyond the joint itself. In a small place like Clapgate, homes can be exposed to wind and rain, which finds any gap, and damp in older walls is slow to dry out.
Homes and businesses are quoted the same way: how much there is to do, how we reach it and what it needs, along with when we can work on site. Ask us for a quote and we will explain what it covers.
Why choose Mr Mastic in Clapgate
- Old sealant always removed completely
- White, clear, grey or another colour, product permitting
- 180+ five-star Google reviews
- ARBOMaster approved applicator
Take a look at how sealant jobs are priced or our reviews.
FAQs for Clapgate
Will you come out to Clapgate?
Yes. Clapgate is within the area we cover, which takes in towns, villages and rural addresses. Our work covers London and the South East. Just mention lanes, gates or anything else about the route when you book.
Can you help a landlord with a rental near Bishops Stortford station?
Yes, rental work is part of what we do. Just phone 0345 464 0079 or send us an email and tell us about the property, and we will give you a clear price.
Do you take out the old sealant first?
Always. Sealing over the old bead is the commonest cause of early failure, so we never do it.
How long before the joint can be used?
Many sealants skin over quickly but take longer to cure fully. We’ll give you the cure time for the product we used.
Can you work on commercial sites?
Yes, regularly. Larger jobs can be planned room by room or area by area.
Is it OK to fill a movement joint with cement?
No. Rigid materials cannot move with the wall, so the joint stops doing its job. If it has already been filled, we can normally cut it out and reseal it.
Are you an approved applicator?
Yes. We’re approved under the ARBOMaster scheme, which is run for the Arbo sealant brand.
How long does external mastic last?
It varies from wall to wall: joints on exposed walls or with a lot of movement age sooner. Check them each year and reseal when they split or harden. Every job carries our 12-month guarantee.
Common problems we fix in Clapgate
UV, rain and frost all age exterior sealant. Over the years it hardens, cracks on the surface and loses its give, so the next time the wall moves, it splits or pulls away.
If you can see any of these, it’s time to have the joints looked at:
- Failed sealant between panels on a façade
- Cracked joints where brick meets render or frames
- Water getting into walls through failed joints
- Movement joints with cracked, split or missing sealant
Homes close to Church of St Mary include some older properties, and an extension built onto an older house moves differently, and the joint between them takes the strain.
Comparing quotes
- What the quote includes, VAT included or not
- What happens if the job turns out different
- How much experience the applicator has
- What product goes in the joint
Landlord and commercial work in Clapgate
We work for letting agents and landlords as well as homeowners. Resealing between tenancies keeps a property looking cared for before the next move-in.
Failed sealant is one of the commonest items on a check-out report, and it’s easy to sort out between tenants. We can quote for more than one property at once.
What the job involves on each surface
Copings and trims
Joints in copings, parapets and trims are exposed to the worst of the weather. Each is resealed with a weatherproof, flexible sealant.
Joints between dissimilar materials
Brick against render, concrete against metal, stone against timber: every change of material is a joint. We seal the joint with a flexible exterior sealant so neither cracks the other.
Towns and villages near Clapgate
Other services in Clapgate
DIY versus a professional finish
A DIY attempt doesn’t rule out a professional job. We remove it and do the joint properly, so just mention it when you contact us.
If you’re set on DIY, put the effort into preparation: take out all the old sealant, make sure the joint is clean and dry, and give it the full cure time. If it doesn’t work out, we can still put it right.