Hertfordshire · England
Todd's Green External Mastic
Sealing brickwork movement joints, render, cladding and façade joints for householders, landlords and businesses in Todd's Green. Fully insured, ARBOMaster approved and guaranteed for a year.
- Movement joints filled with mortar instead of sealant
- Weeds or debris growing in open joints
- Joints where the bead has come unstuck
External mastic in Todd's Green
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. We pick a colour that sits well with the wall so the line blends in. We work on copings & trims, render & cladding joints and concrete & block, and common reasons people get in touch are weeds or debris growing in open joints and failed seals between different materials.
In a village or hamlet like Todd's Green, older cottages and farm buildings often stand in the open, where walls and rooflines take the weather head on. Gutter joints and wall joints there need a sealant that can flex and stay put.
We stand behind the work with a one-year guarantee.
- Place
- Todd's Green (SG1)
- Region
- Hertfordshire
- Cover
- One year on every job
- Quote
- Quoted before any work starts
- Telephone
- 0345 464 0079
- Page updated
- 26 October 2026
How the job changes by 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 neither cracks the other.
Cladding and façade panels
If the façade has a specified sealant, that is what we use, or one the system allows. Tell us what the building has when you get in touch.
Why it’s worth doing now in Todd's Green
Pointing a movement joint with mortar might seem a neat fix, but it stops the joint moving. The movement then cracks the brickwork or render nearby. A flexible sealant over backing rod is what the joint needs. In a small place like Todd's Green, homes can be exposed to wind and rain, which finds any gap, and damp in older walls is slow to dry out.
A few things move the cost up or down: how much old sealant there is and how stubborn it is, any mould to treat, and whether we need extra access for height. Your quote takes all of that into account.
Why book with us
- We’re fully insured
- 20+ years of sealant experience
- 12-month guarantee on every job
- White, clear, grey or another colour, product permitting
Read what affects the cost or customer reviews.
Landlords, agents and businesses in Todd's Green
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.
Failed sealant is one of the commonest items on a check-out report, and it’s quick to put right between tenancies. We can quote for more than one property at once.
Keeping the joints in good condition
Joint life depends on how it’s used and looked after. We suggest:
- Keep high-pressure jets off the joints
- Ask before painting over external sealant
- Keep soil, plants and ivy away from the joints
- Point out the joints to other trades
Only paint over the joint if we have confirmed the sealant can take paint. Paint can crack on a flexible joint, and paint can crack as the joint moves.
An open movement joint lets rain into the wall every time it pours. That can lead to damp patches, staining and frost damage, all bigger jobs than a reseal.
Towns and villages near Todd's Green
Other services in Todd's Green
Todd's Green: your questions answered
Is Todd's Green within the area you cover?
Yes, smaller places are covered as well as towns. Our work covers London and the South East. Let us know about access, parking and anything unusual about getting there when you book.
Can you help a landlord with a rental near Stevenage station?
Yes. We work for letting agents and landlords as well as householders, and several properties can be quoted together. You can call 0345 464 0079 or send us an email with the details for a clear quote.
Do I need to be at home?
That depends on where the joints are. For work indoors, someone needs to let us in.
Will it make a mess?
We keep the work tidy. Nearby surfaces are protected, and we clear up when we are done.
Is the work guaranteed?
Yes. Every job comes with our one-year guarantee.
Will the new joint stand out?
The sealant colour is picked to suit the wall so the joint blends in. Exterior sealants come in a good range of colours.
Can I do it myself?
Sometimes. Preparation is everything: all the old sealant out, and a clean, dry joint. We can always put it right if it fails.
Is it OK to seal over old sealant?
No. We remove every bit of old sealant first, so the new joint bonds to clean surfaces.
Can I do it myself?
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, and the work is guaranteed for a year.
Some sealant jobs are within reach of a careful DIYer, such as a straightforward joint indoors. The common mistakes are sealing over old sealant, sealing a damp joint and using far too much.
Do you need external mastic in Todd's Green?
A lot of failed joints come down to preparation: dusty or wet faces, no primer where one was needed, or old sealant left in. The new sealant then lets go long before it should.
People normally contact us when they notice one of these:
- Failed sealant between panels on a façade
- Weeds or debris growing in open joints
- Failed seals between different materials
- Damp patches traced to an open external joint
If you let a flat or house near Stevenage station, split movement joints are easy to miss on a rental until damp shows inside.
Questions to ask before booking
- Is the old sealant removed completely?
- Which sealant they’ll use, and why
- What the quote includes, VAT included or not
- Whether they’re fully insured
Todd's Green buildings and the weather
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. With historic houses such as Knebworth House (about 3.5 miles south) nearby, there’s older building stock in the area around Todd's Green as well as newer homes. In older buildings, older walls and rooflines need a sealant that moves with them and suits the material.
If you live in an older home near Church of St Mary the Virgin, old and new materials meet at the roofline and walls, which is where sealant earns its keep. If you look after a building such as The John Henry Newman School, its movement joints, gutters and trims need looking after like any other building’s.
Todd's Green is about 2 miles north-west of Stevenage, in Hertfordshire. Jobs in Todd's Green get the same care as everywhere else we work: the old material taken out, joints prepared properly and a 12-month guarantee. Our Hertfordshire coverage runs to 381 places, Todd's Green among them. For nearby work, see our London page (30 miles or so).
All of SG1 is within our area for external mastic, from the main roads to the quietest streets. We also cover the places around Todd's Green: Lower Titmore Green (1 mile west), Titmore Green (1 mile west), Little Wymondley (1 mile north-west), Graveley (1 mile north-east) and Great Wymondley (1 mile north). Larger places within reach include Hemel Hempstead (15 miles south-west), St Albans (13 miles south), Welwyn Garden City (9 miles south), Harpenden (9 miles south-west), Hitchin (3 miles north-west) and Hoddesdon (15 miles south-east).
Landmarks near Todd's Green
Around Todd's Green, our work takes us to homes and buildings near Hermit of Redcoats pub and Graveley Primary School, among other places. For rail, the closest station is Stevenage station, roughly 1.7 miles south-east of the centre. Other landmarks nearby include Lister Hospital (0.6 miles east) and Stevenage Museum (1.9 miles south-east). For a walk, there’s Purwell Ninesprings.
How it works
All our tools and materials come with us in the van, so there’s nothing for you to buy. After a quick look at the joints together, we protect the area and start. It normally takes a few hours to a few days, depending on the length of joint and the access. For a village or hamlet like Todd's Green, the journey is planned in advance: tell us about narrow lanes, gates, long drives and where we can park. We bring what the job needs, so it can be finished in one trip where possible.
- We start by checking each joint, agreeing the ones to redo and how we will reach them.
- The old mastic and anything lodged in the joint is removed.
- 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.
- We gun in a flexible exterior sealant in a colour that suits the wall and tool it neatly.
Getting ready for the visit
- Let us know about parking restrictions
- On commercial sites, let us know about site rules
- Tell us about any water getting in
Ask for a quote
Getting a quote is simple: let us know the job and the location and its rough size. A few pictures by email make the job easier to understand, and we’ll come back to you with a quote.