Hertfordshire · England
Temple Dinsley External Mastic
Sealing brickwork movement joints, render, cladding and façade joints in Temple Dinsley, with a one-year guarantee on every job. Ask us for a quote.
- Moss and dirt in joints with no sealant left
- Rigid filler in a joint that should flex
- Sealant that has lost its bond to the brick or render
External mastic for homes and businesses in Temple Dinsley
For buildings in Temple Dinsley, we reseal external joints of all kinds, from brick movement joints to cladding panels. The preparation is the same whatever the wall: clean joint faces and the right depth. Typical jobs include rain getting behind render or cladding at a joint and rigid filler in a joint that should flex, across joints between brick and frames, copings & trims and façade panels.
Outside joints can only be sealed when they’re dry, so work in Temple Dinsley is booked around the forecast. Let us know about access to every wall, plus any garages or outbuildings.
Our work is backed for twelve months, in Temple Dinsley and everywhere else we cover.
- Location
- Temple Dinsley (SG4)
- Region
- Hertfordshire
- Guarantee
- 12 months on all our work
- Quote
- A clear price before we start
- Phone
- 0345 464 0079
- Updated
- 26 October 2026
What the job involves on each surface
Joints between dissimilar materials
Brick against render, concrete against metal, stone against timber: every change of material is a joint. A flexible sealant bridges the two so the movement is taken up.
Brickwork movement joints
Brick walls have vertical movement joints to absorb expansion. We reseal them with a low-modulus sealant over backing rod.
Work for landlords, hotels and businesses
Letting agents and landlords in Temple Dinsley can book us as well as homeowners. Sealant work between tenants keeps a property looking cared for before the next move-in.
A neglected joint can let water reach the structure, which matters even more when someone else lives there. Resealing at the right time is simple maintenance that we can handle for you.
Questions from Temple Dinsley
Will you come out to Temple Dinsley?
Yes, we do. We work across London and the South East, from towns to the smallest places. Longer journeys are simply planned in advance.
I let a flat near Stevenage station. Can you help?
Yes. We work for letting agents and landlords as well as homeowners. You can ring 0345 464 0079 or send us an email with the details for a clear quote.
Do you use backing rod?
The foam is closed-cell backing rod. It stops the sealant going in too deep and bonding to three sides, which would stop it stretching.
Are you an approved applicator?
Yes. We’re ARBOMaster approved, the scheme for applicators of Arbo sealants.
Do you work at height?
That depends on the building and the joints. We work on joints that can be reached safely. Tell us about the building and we will confirm what access is needed.
What’s an expansion joint in brickwork?
Most straight vertical gaps in brickwork are movement joints. It gives the wall room to move.
Can new sealant go over the old?
No, and we never do. It may look fine at first, but the new bead soon lifts. The old sealant has to come out completely.
Are you insured?
Yes. We are fully insured.
The process
We keep the work tidy and contained to the area we are working on. Expect the work to take 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 like Temple Dinsley needs a little journey planning: let us know about lanes, gates and parking. Everything for the job comes with us, so a second trip is avoided where possible.
- We start by walking round the building and agreeing the joints and the access.
- Every bit of old sealant and any mortar or debris is cut out.
- The faces are brushed clean and primed where the product requires it.
- Backing rod sized to the joint goes in to set the depth.
- The exterior sealant is applied, tooled and checked along its length.
Before we arrive
- For indoor joints, keep the area dry beforehand if you can
- Plan for the work area to be out of bounds to pets and children
- For business premises, tell us about site rules or sign-in
Getting a quote
Need a quote? Please ring 0345 464 0079 or drop us an email and tell us about the job. You’ll know what we plan to do, and what it will cost, before any work begins.
Read more
How to look after the new joints
Joint life depends on how it’s used and looked after. We suggest:
- Fix overflowing gutters above sealed joints
- Leave the joints unpainted unless we have said otherwise
- Avoid pressure-washing directly into sealant joints
- Keep movement joints as flexible joints, not mortar
Give the sealant the cure time we tell you before anything rubs against it. The surface skins over quickly, but full cure takes longer.
Leaks behind façade panels and render often go unseen. When it finally shows inside, the joint may have been open for years.
Do you need external mastic in Temple Dinsley?
Buildings move more than people expect. Clay bricks expand slightly over their life, concrete and block shrink, and everything moves with temperature and wet. All of that ends up in the joint sealant.
Signs it’s time to call us include:
- Old sealant gone brittle and cracked
- Cracked joints where brick meets render or frames
- Movement joints with cracked, split or missing sealant
- Water getting into walls through failed joints
In the older streets around Church of St Martin, older walls, gutters and the joints where extensions meet them need a flexible sealant.
What your quote should include
- What happens if the job turns out different
- What guarantee comes with the work
- What the cure time is
- Who does the work, and how experienced they are
What sealant work can’t fix
New sealant cannot fix everything, and we’d rather say so up front. Sealant won’t put right:
- Structural movement, which needs a surveyor or engineer
- Damp that isn’t coming from the joint
- Cracking across the wall rather than at a joint
Not sure which it is? You can phone 0345 464 0079 or send us an email and we’ll tell you honestly.
Where we work in Temple Dinsley
- Brickwork movement joints
- Joints between brick and frames
- Concrete & block
- Copings & trims
- Render & cladding joints
- Façade panels
Nearby places to Temple Dinsley
Other services in Temple Dinsley
Walls and rooflines in Temple Dinsley
Rainfall in the South East is lower than in much of the UK, yet outdoor joints still have to be sealed dry, so jobs are booked with the weather in mind. Historic houses like Knebworth House (about 3.5 miles south-east) are a reminder that the area around Temple Dinsley has older buildings as well as new. In older buildings, older walls and rooflines need a sealant that moves with them and suits the material.
For landlords with property near Stevenage station, failed wall and movement joints let damp in, so they’re worth checking between tenancies. Schools such as Preston Primary School are buildings too, and its movement joints, gutters and trims need looking after like any other building’s.
Temple Dinsley is about 3 miles south of Hitchin, in Hertfordshire. If you need external mastic in Temple Dinsley, it’s easy to get a quote: please call 0345 464 0079 or send us an email. We’re based in Crawley and cover Hertfordshire, Temple Dinsley included. We cover 381 towns and villages across Hertfordshire. Our London page covers work nearby.
Postcode districts we cover here for external mastic: SG4. If you need external mastic at a property on St Albans Highway and Hitchwood Lane or a nearby road, we can help. Other places close to Temple Dinsley include Poynders End (1 mile north-east), Preston (1 mile west), Langley End (1 mile south-east), Little Almshoe (1 mile north-east) and St Ibbs (1 mile north-east). Further out, we also cover Hemel Hempstead (13 miles south-west), Stevenage (4 miles east), St Albans (11 miles south), Welwyn Garden City (8 miles south-east), Harpenden (7 miles south-west) and Hitchin (3 miles north).
Local landmarks in Temple Dinsley
Typical jobs here are in homes near The Red Lion Public House, among other places. The closest station to Temple Dinsley is Stevenage station, about 2.9 miles east of the centre. Nearby you will also find North Hertfordshire Museum (2.9 miles north) and Lister Hospital (2.9 miles north-east). Green spaces nearby include Markham's Hill and Purwell Ninesprings.
Should I try it myself first?
A careful DIYer can reseal a simple joint, like a short, easy-to-reach joint indoors. Where it goes wrong is sealing over the old bead, working on a wet joint or overloading the gap.
Sealing over old silicone is the commonest DIY error. New silicone will not bond to old, so it peels away and traps moisture behind it. Everything old must be removed first.