Essex · England
Great Parndon External Mastic
Professional external mastic in and around Great Parndon, with old sealant always removed completely and a one-year guarantee.
- Moss and dirt in joints with no sealant left
- Sealant pulling away from one side of the joint
- Rigid filler in a joint that should flex
How it works
When we get to you, we check the joints match what you told us. If anything is different, we explain it before carrying on. After that, the work takes a few hours to a few days, depending on the length of joint and the access. Parking around Great Parndon is usually easier than in a town centre, but mention any lanes, gates or long drives. For outside work, side access and the height of the joints help us plan.
- We start by walking round the building and agreeing the joints and the access.
- We cut out the old mastic and rake out anything in the joint.
- Joint faces are cleaned back and primed if the sealant needs it.
- We fit closed-cell backing rod to control the depth.
- The exterior sealant is applied, tooled and checked along its length.
Getting ready for the visit
- Let us know about earlier repairs to the joints
- Keep pets and children clear of the area while we work
- Let us know if you’ve seen damp or leaks
Getting a quote
We quote each job on its own. Simply phone 0345 464 0079 or drop us an email and describe the job, and photos are welcome.
Related advice
How we handle external mastic in Great Parndon
Where two different materials meet, such as brick and render or blockwork and metal, they move at different rates. A flexible sealant bridges the two where mortar or filler would crack. If you have old sealant gone brittle and cracked and movement joints filled with mortar instead of sealant, we can put it right, whatever the surface.
In a smaller place like Great Parndon, some homes face open ground, and walls and rooflines facing the weather take the worst of it. That’s where gutter joints and wall joints tend to fail first.
Each job carries a 12-month guarantee, whatever its size.
- Where
- Great Parndon (CM19, CM18)
- Wider area
- Essex
- Guarantee
- A year, on every job
- Quote
- A clear price before any work starts
- Phone
- 0345 464 0079
- Last updated
- 26 October 2026
Should I try it myself first?
The biggest DIY mistake is sealing over old sealant. New silicone will not bond to old, so it peels away and traps moisture behind it. All the old material has to come out first.
The difference is mostly in the preparation and the product. We take joints back to clean, dry surfaces, and the sealant is chosen for how the joint moves and where it is.
Surface by surface
Cladding and façade panels
Panels heat up and cool down quickly, so the joint sealant has to cope with frequent movement. The sealant is chosen with that in mind.
Concrete and blockwork
Concrete faces can be dusty and porous, so cleaning and priming matter. We prime where the sealant needs it before the bead.
Landlord and commercial work in Great Parndon
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 easy to sort out between tenants. We can quote for more than one property at once.
Do you need external mastic in Great Parndon?
Joints sealed without backing rod, or far too deep, rarely last. If the sealant sticks to the back as well as the sides, it cannot stretch and rips as the joint opens.
Signs it’s time to call us include:
- Rigid filler in a joint that should flex
- Panel joints letting water in
- Moss and dirt in joints with no sealant left
- Movement joints with cracked, split or missing sealant
In the older streets around Church of St Mary the Virgin, an extension built onto an older house moves differently, and the joint between them takes the strain.
Questions to ask before you book
- How hidden problems are handled
- Whether the sealant suits the joint
- How the surfaces are prepared before sealing
- What insurance they hold
Also near Great Parndon
Other services in Great Parndon
What affects the quote in Great Parndon
We don’t publish a price list, because jobs vary so much. What we look at:
- Any mould that needs treating
- Which sealant suits the joint
- The number and length of the joints
- How much old sealant there is and how hard it is to remove
Every job is a little different, so we quote each one individually. Size, access and the product the joint needs all make a difference.
Asking for a quote
When you call or email, these details help:
- Any previous sealing or DIY work
- How we’d reach the joints
- The problem you’ve noticed
- If it’s domestic, commercial or a hotel
We don’t publish a price list, because every job is different. Instead, we send you a clear quote for your job. To arrange one, ring 0345 464 0079 or send us an email.
Common questions in Great Parndon
Do you cover smaller places like Great Parndon?
Yes, smaller places are covered as well as towns. We work across London and the South East. Just mention lanes, gates or anything else about the route when you book.
Do older homes in Great Parndon need their sealant replacing?
Generally, yes, if it’s cracked, shrunk, mouldy or coming away. New sealant will not stick to old, so the old bead has to come out completely first.
What should I tell you?
Tell us what needs doing and where, with photos by email if possible. We’ll ask anything else we need to know.
Do you take out the old sealant first?
Yes, always, and completely. New silicone doesn’t stick to old silicone, so any old material comes out before anything new goes in.
How long before the joint can be used?
Cure times vary by product and the conditions. Before we leave, we’ll tell you the cure time.
Can you quote for more than one area?
Of course. Combining jobs makes good use of the visit, so mention them when you ask for a quote.
Will you leave a mess?
No. We work neatly, protect the area around the joints and tidy up afterwards.
Do you work for letting agents?
Yes, regularly. We can quote for several properties at once.
Aftercare tips
Aftercare is simple, and it makes a real difference:
- Keep water from gutters off the wall
- Keep movement joints as flexible joints, not mortar
- Wash walls gently around the sealant
- Check external joints each spring
Have a quick look at the joints each spring. Watch for splits, edges coming away or growth in the joint.
Leave a failed movement joint and water keeps getting into the wall. Over time it can mean damp inside, stained render or frost-damaged brick which cost more to put right than the joint.
External mastic in Great Parndon: local notes
Great Parndon is part of Harlow, one of the post-war new towns. Many homes date from the post-war decades and were built in phases, so whole streets can have gutters, trims and wall joints reaching the end of their life together. 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.
If you look after a building such as Jerounds Primary Academy, larger buildings have long runs of movement joint that eventually need resealing. If you let a flat or house near Harlow Town station, split movement joints are easy to miss on a rental until damp shows inside.
Great Parndon is about 2 miles south-west of Harlow, in Essex. If you need external mastic in Great Parndon, please ring 0345 464 0079 or drop us an email for a quick quote. We’re based in Crawley and cover Essex, Great Parndon included. Great Parndon is one of 644 places in Essex we cover. Our Chelmsford page covers work nearby.
Our applicators cover all of the CM19 and CM18 postcode area for external mastic. You’ll find streets such as Rectory Lane, Pyenest Road and Paycock Road, and we cover them all. We also cover Staple Tye (1 mile south-east), Tylerscross (1 mile south-west), Jack's Hatch (1 mile south), Little Parndon (1 mile north) and Broadley Common (1 mile south-west). Further out, we also cover Brentwood (13 miles south-east), Loughton (8 miles south), Waltham Abbey (6 miles south-west), Great Dunmow (14 miles north-east), Epping (4 miles south) and Stansted Mountfitchet (11 miles north-east).
What’s near Great Parndon
Typical jobs here are in homes near Hawkenbury Meadow, Stewards Academy - Science Specialist and The Cock Inn and the streets around them. For rail, the closest station is Harlow Town station, roughly 1.8 miles north of the centre. Well-known places in the area include Mark Hall Cycle Museum (2.4 miles north-east) and Princess Alexandra Hospital (1 mile north). Green spaces nearby include Hunsdon Mead.