Hertfordshire · England
Hertford Heath External Mastic
Problem with your movement joints in Hertford Heath? We remove the old material, prepare the joints and seal them properly, with a 12-month guarantee.
- Movement joints with cracked, split or missing sealant
- Moss and dirt in joints with no sealant left
- Failed seals between different materials
External mastic in Hertford Heath, done properly
Joints in render and cladding are easy to overlook until a damp patch appears. We look over the joints, agree the ones to renew and reseal with a flexible, weatherproof product. We work on brickwork movement joints, render & cladding joints and façade panels, and people most often call us about weeds or debris growing in open joints and panel joints letting water in.
Around Hertford Heath, older buildings can be stone, brick or timber-framed, many with extensions added later. Where one material meets another is where water usually gets in.
We guarantee the work for a year. If something isn’t right with it in that time, tell us and we will put it right.
- Location
- Hertford Heath (SG13)
- Wider area
- Hertfordshire
- Cover
- 12 months on all our work
- Quote
- Quoted before any work starts
- Call
- 0345 464 0079
- Page updated
- 26 October 2026
Keeping the joints in good condition
How long the joints last depends on use and care. We suggest:
- Wash walls gently around the sealant
- Keep soil, plants and ivy away from the joints
- Have failed joints looked at early
- Tell anyone working on the walls about the movement joints
Keep the joints clear of soil, plants and climbing growth. Anything that holds water against the joint wears it out sooner.
Gaps, plants or missing sealant in a joint are worth getting looked at. Early work is quicker and leaves a better finish.
The process
A visit follows a simple pattern: we check the joints, mask and protect the surrounding surfaces, carry out the job and tidy away. It normally takes anything from a few hours to several days, depending on the building. In a small place like Hertford Heath, access is normally the main thing to plan. For outside work, also let us know about exposed walls and any outbuildings involved.
- First we look over the joints with you, agree which to renew and talk through access.
- We cut out the failed sealant and rake out any dirt or growth.
- 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.
- A flexible exterior sealant is applied and tooled in a colour to suit the wall.
Before we arrive
- Tell us about any previous sealing or DIY attempts
- Clear items away from the joints we are working on
- Let us know if you’ve seen damp or leaks
Get a quote
The more we know about the job, the more useful the quote. Tell us where the job is, what’s wrong and how much there is, and add photos by email if you can.
Related advice
Hertford Heath questions
Will you come out to Hertford Heath?
Yes, Hertford Heath is covered. Our work covers London and the South East, and smaller places are part of that. Longer journeys are simply planned in advance.
Is Hertford Heath in your area for external mastic?
Yes. We work across London and the South East, and Hertford Heath is part of that. Just call 0345 464 0079 or drop us an email with a few details of the job, and we will send you a clear quote.
How do you reach high-level joints?
It depends on the height and the site. Low-level joints are straightforward; for higher work, tell us about the building and we’ll confirm what’s needed.
Can you seal joints between two different materials?
Yes. Materials like render, brick, metal and uPVC all move differently, so a flexible sealant is needed where they meet. We choose one that suits both surfaces.
Do you have insurance?
Yes, we are fully insured.
What does external mastic cost?
There’s no set price, as it depends on the job: how much there is, what’s there now, how we reach it and what it needs. You’ll get a clear quote before we start.
Is it worth trying it myself?
Sometimes. Preparation is everything: all the old sealant out, and a clean, dry joint. If it does not work out, we can redo it.
Which products do you use?
Each joint gets the product that suits it. Movement, water and weather all affect the choice, and we’ll explain our choice.
Leave it or put it right?
Mortar or ordinary filler might look like a quick way to close an open joint, but it stops the joint moving. The wall then cracks somewhere else. The correct repair is a flexible sealant with the right backing. In a small place like Hertford Heath, homes can be exposed to wind and rain, which finds any gap, and damp in older walls is slow to dry out.
The cost depends on the size of the job, how hard the old material is to remove and access to the work. You’ll have a clear quote before any work starts, so you know where you stand.
Why book with us
- Experience in homes, commercial sites and hotels
- Quality sealants from Arbo and Everbuild
- Anti-fungal sanitary silicone in wet areas
- An ARBOMaster approved applicator
Read what affects the cost and what customers say.
Outside joints around Hertford Heath
The South East is one of the drier parts of the UK, yet outdoor joints still have to be sealed dry, so jobs are booked with the weather in mind.
Managing a site like Hertford Heath Primary and Nursery School? Then larger buildings have long runs of movement joint that eventually need resealing. If you let a flat or house near Hertford East station, outside joints that have cracked can let damp into a rental, so check them between lets.
Hertford Heath is about 2 miles south-east of Hertford, in Hertfordshire. We carry out external mastic for householders, landlords and businesses in Hertford Heath and nearby. Across Hertfordshire, we cover 381 places, and Hertford Heath is one of them. Our London page covers work nearby, about 20 miles away.
Postcode districts we cover here for external mastic: SG13. Streets in the area include London Road, Woodland Road and Trinity Road. With the B1197 close by, Hertford Heath is simple for us to get to. Close by, we work in Little Amwell (1 mile east), Foxholes (1 mile north-west), Rush Green (1 mile north), Hailey (1 mile east) and Woollensbrook (1 mile south-east). Larger places within reach include Stevenage (10 miles north-west), St Albans (12 miles west), Bishop's Stortford (10 miles north-east), Welwyn Garden City (6 miles west), Harpenden (13 miles west) and Hitchin (15 miles north-west).
What’s near Hertford Heath
Typical jobs here are in homes near The College Arms, Simon Balle All-Through School and Barclay Park and the streets around them. Hertford Heath’s nearest station is Hertford East station, about 1.6 miles north-west of the centre. Nearby you’ll also find Hertford County Hospital (2.1 miles north-west) and Museum of Street Lighting (1.5 miles north-east). Open spaces near Hertford Heath include Hertford Heath nature reserve.
Do you need external mastic in Hertford Heath?
A lot of failed joints come down to preparation: joint faces that were dusty or damp, unprimed where they needed it, or still carrying old sealant. The new sealant then lets go long before it should.
If you can see any of these, it’s time to have the joints looked at:
- Joints where the bead has come unstuck
- Rigid filler in a joint that should flex
- Moss and dirt in joints with no sealant left
- Damp patches traced to an open external joint
For an older house near a landmark such as Church of the Holy Trinity, an extension built onto an older house moves differently, and the joint between them takes the strain.
What your quote should include
- Whether you can choose the colour
- What guarantee comes with the work
- Which sealant they’ll use, and why
- Whether they seal over old material or remove it
Towns and villages near Hertford Heath
More services for Hertford Heath
How we quote for external mastic
The price is agreed before any work begins. It’s based on:
- How many areas need sealing
- Whether the work is at height
- The type of sealant required
- The size of the job
Homes and businesses are quoted the same way: the amount of work, the access and the products needed, along with when we can work on site. Ask us for a quote and we will go through it with you.
What to tell us for a quote
You don’t need to know the technical terms. Just tell us:
- The problem you’ve noticed
- Photos by email, if that’s easy
- If it’s domestic, commercial or a hotel
- Where the job is, and your postcode
For external mastic in Hertford Heath, ring 0345 464 0079 or email us. A short description of the job and where it is helps us quote, and you will get a clear quote before any work starts.
Can I do it myself?
A careful DIYer can reseal a simple joint, such as a straightforward joint indoors. Where it goes wrong is sealing over the old bead, working on a wet joint or overloading the gap.
If you do try it yourself, take your time over the preparation: take out all the old sealant, make sure the joint is clean and dry, and give it the full cure time. If it does not work out, we can still put it right.
Landlords, agents and businesses in Hertford Heath
We also work for property managers and facilities teams. Several sites can go on one quote, and we are fully insured.
From a single let to a portfolio, you get the same standard of work: old sealant fully removed, joints prepared properly and a 12-month guarantee.