Hertfordshire · England
Apsley End External Mastic
Movement joints in Apsley End need attention? We remove the old material, prepare the joints and seal them properly.
- Movement joints filled with mortar instead of sealant
- Damp patches traced to an open external joint
- Movement joints with cracked, split or missing sealant
How the job changes by surface
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.
Concrete and blockwork
Concrete faces can be dusty and porous, so cleaning and priming matter. A primer goes on where the product requires one before the bead.
External mastic in Apsley End
A movement joint is only as good as its depth. Closed-cell backing rod sets the depth and stops the sealant sticking to the back, so it bonds to the two sides only and can stretch. Common call-outs are for panel joints letting water in and gaps where render, brick and frames meet, across joints between brick and frames, render & cladding joints and brickwork movement joints.
Somewhere as small as Apsley End, homes and farm buildings often face open ground, so walls and rooflines take the full force of wind and rain. Joints on those walls need a sealant that moves with the building and stays in place.
There’s a 12-month guarantee on every job, whatever its size.
- Place
- Apsley End (SG5)
- Wider area
- Hertfordshire
- Guarantee
- 12 months on all our work
- Quote
- A clear quote up front
- Call
- 0345 464 0079
- Last updated
- 26 October 2026
Why it’s worth doing now in Apsley End
The longer a joint stays open, the more water the wall takes in. Wet masonry is more easily damaged by frost, so the damage spreads beyond the joint. Where a wall is exposed, as many are in small places like Apsley End, wind-driven rain gets into any failed joint, and older walls, once damp, take a long time to dry.
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 the work is at height. We take all of that into account in your quote.
What you get with us
- Colour picked to suit the job
- Any old sealant cut out fully, not covered over
- ARBOMaster approved applicator
- 180+ five-star Google reviews
Take a look at how sealant jobs are priced and customer reviews.
How the visit works
We work through the job in order: protection first, then preparation, sealing and a tidy-up. For most jobs that takes a few hours to a few days, depending on the length of joint and the access and we leave things clean and tidy. Somewhere as small as Apsley End, access is often the only tricky part. For outside work, also let us know about exposed walls and any outbuildings involved.
- First, the joints are inspected and the access agreed.
- We cut out the old mastic and rake out anything in the joint.
- The faces are brushed clean and primed where the product requires it.
- Backing rod sized to the joint goes in to set the depth.
- We apply the sealant, tool it and check the whole run.
How to prepare
- Where the joints are inside, avoid wetting them before we arrive
- Tell us about access, such as stairs, a lift or high-level joints
- Let us know if you’ve seen damp or leaks
Getting a quote
Asking for a quote is easy: tell us what needs doing and where and its rough size. A few photos by email make the job easier to understand.
Advice
External mastic in Apsley End: local notes
Rainfall in the South East is lower than in much of the UK, but outside sealant still needs a dry, clean surface, so outdoor work is planned around the forecast.
Managing a site like Shillington Lower School? Then larger buildings have long runs of movement joint that eventually need resealing.
Apsley End is about 5 miles north-west of Hitchin, in Hertfordshire. Homes, rented property, offices and hotels in Apsley End can book us for external mastic, old or new, large or small. Every job comes with our one-year guarantee. Our Hertfordshire coverage runs to 381 places, Apsley End among them. London is on our list too, about 36 miles from Apsley End.
We work across the SG5 postcode area for external mastic and the streets around it. That includes homes and businesses on Hanscombe End Road, Sandy Heath Close and Chalkley Bush Close. We also cover the places around Apsley End: Hanscombe End (1 mile north), Shillington (1 mile north-east), Hexton (2 miles south-west), Pegsdon (2 miles south) and Pirton (2 miles south-east). Larger places within reach include Stevenage (10 miles south-east), Welwyn Garden City (15 miles south-east), Harpenden (12 miles south), Hitchin (5 miles south-east), Letchworth (6 miles east) and Letchworth Garden City (6 miles east).
What’s near Apsley End
In Apsley End, that means homes and buildings near The Musgrave Arms Shillington and the streets around them. Well-known places in the area include Keech Hospice Care (5 miles south-west) and Stondon Motor Museum (2.6 miles north-east). Green spaces nearby include Cain Hill and Pegsdon Hills.
Honest limits
New sealant can’t fix everything, and we will tell you before work begins. It will not solve:
- Cracking across the wall rather than at a joint
- Movement that is more than a sealant joint can take
- Cutting new joints into brickwork, which is building work rather than sealant work
Not sure which it is? You can call 0345 464 0079 or drop us an email and we will tell you honestly.
What we seal
- Concrete & block
- Render & cladding joints
- Joints between brick and frames
- Façade panels
- Brickwork movement joints
- Copings & trims
Landlords, agents and businesses in Apsley End
Letting agents often deal with us directly. Send the address, what’s needed and the access arrangements.
Housing providers, facilities teams and property managers book us too in Apsley End and across Hertfordshire. We can quote a run of properties together, and we’re fully insured for the work.
Towns and villages near Apsley End
More services for Apsley End
FAQs for Apsley End
Can you do external mastic in Apsley End?
Yes. Our work covers London and the South East, and Apsley End is part of that. You can phone 0345 464 0079 or send us an email and let us know what needs doing, and we will give you a clear quote.
Will you come out to Apsley End?
Yes, we do. Our work covers London and the South East, and smaller places are part of that. Longer journeys are simply planned in advance.
Will there be a smell?
Some sealants have a smell while they cure, which fades as it sets. Ventilation helps.
What information do you need?
Only a few details: where it is, what you’ve noticed and how we reach it. Then ring 0345 464 0079 or send us an email.
How long before the joint can be used?
That depends on the sealant used, so please follow the time we give you when we finish.
Do you hold any approvals?
Yes. We are ARBOMaster approved, the scheme for applicators of Arbo sealants.
Do I have to be there?
We need access to the joints, so we’ll agree that with you when we book. Indoors, that generally means someone at home.
How long does external mastic last?
That depends on the wall, the weather and the movement. Signs to watch for are cracking, hardening and gaps at the edges, and reseal at that point.
What we’re called out for in Apsley End
Sunlight, wet weather and frost wear exterior sealant down. 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.
Keep an eye out for these signs:
- Joints where the bead has come unstuck
- Hard, crazed mastic that has stopped moving
- Rain getting behind render or cladding at a joint
- Weeds or debris growing in open joints
Homes close to Church of All Saints include some older properties, and an extension built onto an older house moves differently, and the joint between them takes the strain.
What your quote should include
- Whether the sealant suits the joint
- Who turns up on the day
- Are they insured?
- How the colour is chosen
Aftercare tips
How long the joints last depends on use and care. We suggest:
- Avoid pressure-washing directly into sealant joints
- Get split or bare joints resealed while the damage is small
- Clear growth from the base of walls and joints
- Check external joints each spring
Follow the cure time we give you before the joint is knocked or disturbed. Most exterior sealants skin fast but take longer to cure right through.
Gaps, plants or missing sealant in a joint are worth getting looked at. Early work is quicker and leaves a better finish.