Hampshire · England
External & façade joints in Blackmoor, Hampshire
Problem with your movement joints in Blackmoor? We cut out the old, prepare the joints and apply the right sealant, and the work is guaranteed for a year.
- Panel joints letting water in
- Damp patches traced to an open external joint
- Moss and dirt in joints with no sealant left
Outside joints around Blackmoor
Compared with the north and west, the South East gets less rain, yet outdoor joints still have to be sealed dry, so jobs are booked with the weather in mind.
Managing a site like St Matthew's Church of England Aided Primary School? Then movement joints, cladding joints and gutters on larger buildings need the same care as a house’s. If you let a flat or house near Liss station, outside joints that have cracked can let damp into a rental, so check them between lets.
Blackmoor is about 5 miles south-east of Alton, in Hampshire. Anywhere in GU33, our applicators can take on external mastic. Our Hampshire coverage runs to 683 places, and Blackmoor is one of them. Portsmouth is on our list too, about 21 miles from Blackmoor.
Every address in GU33 is covered for external mastic, from the main roads to the quietest streets. If you need external mastic at a property on Blackmoor Road and Sotherington Lane or anywhere close by, we can help. We also cover the places around Blackmoor: Woolmer (1 mile south-east), Greatham (1 mile south), Longmoor (2 miles south-east), Passfield (2 miles east) and Weavers Down (3 miles south-east). Within a short drive, we also cover Basingstoke (15 miles north-west), Farnborough (15 miles north), Fleet (13 miles north), Horndean (14 miles south-west), Aldershot (12 miles north-east) and Alton (5 miles north-west).
Landmarks near Blackmoor
Typical jobs here are in homes near Mill Chase Academy. For rail, the closest station is Liss station, roughly 3.5 miles south. A little further out are The Romany Museum (2.3 miles west) and Chase Community Hospital (1.4 miles north-east). The countryside around Blackmoor includes Selborne Hill and Deadwater Valley.
How we handle external mastic in Blackmoor
Short cuts in external joints show up within a season or two. New sealant over old, joints packed with mortar and beads with no backing rarely last long. We strip the joint back and start again. If you’re dealing with gaps where render, brick and frames meet and joints pointed up with cement by mistake, we can help, on concrete & block, brickwork movement joints and joints between brick and frames alike.
External sealant needs dry, clean surfaces, so work around Blackmoor is planned for dry weather. Tell us about access to all sides of the building, including outbuildings and garages.
The work is guaranteed for twelve months. If something is not right with it in that time, tell us and we’ll put it right.
- Location
- Blackmoor (GU33)
- Wider area
- Hampshire
- Cover
- One year on every job
- Quote
- A clear price before we start
- Phone
- 0345 464 0079
- Updated
- 26 October 2026
Signs you need external mastic in Blackmoor
Weeds, moss and debris in a joint are a sign the sealant has gone. Dirt and roots then trap moisture in the joint and speed up the damage.
People usually contact us after spotting something like this:
- Water getting into walls through failed joints
- Failed sealant between panels on a façade
- Plants rooting in failed movement joints
- Old sealant gone brittle and cracked
For an older house near a landmark such as St Matthew's Church, an extension built onto an older house moves differently, and the joint between them takes the strain.
Before you book anyone
- What insurance they hold
- What happens if they find a problem under the old sealant
- How long to leave it before use
- How the joint is cleaned and prepared
How it works
We bring everything the job needs with us, so you do not need to buy or prepare anything. Once we’ve agreed what’s being done, we protect the area and start. Most jobs take a few hours for a handful of joints, longer for a whole elevation. For a village or hamlet like Blackmoor, 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.
- Each joint is checked and the colour of the new sealant agreed.
- We take out the old sealant until the faces are sound.
- Backing rod goes in so the sealant can stretch between the two faces.
- Primer is applied wherever the sealant needs it.
- We gun in low-modulus sealant and tool it neatly.
How to prepare
- Tell us about any previous sealing or DIY attempts
- Let us know about stairs, lifts or work at height
- Move anything stored near the joints
Ask for a quote
To get a quote, ring 0345 464 0079 or send us an email and tell us where the job is and what the problem looks like. We will send you a clear quote before any work starts.
Related advice
When it is not the sealant
Before booking, it’s worth knowing the limits too:
- Cracks in the bricks or render themselves, away from the joints
- Damp that is not coming from the joint
- Structural movement, which needs a surveyor or engineer
Not sure which it is? You can ring 0345 464 0079 or email us and we’ll tell you honestly before you book.
Joints and surfaces we work on
- Façade panels
- Concrete & block
- Joints between brick and frames
- Brickwork movement joints
- Render & cladding joints
- Copings & trims
Blackmoor questions
Is Blackmoor in your area for external mastic?
Yes, Blackmoor is within the area we cover. Our work covers London and the South East. Just ring 0345 464 0079 or email us with a few details of the job, and we will give you a clear price.
Can you help a landlord with a rental near Liss station?
Yes. We work for landlords and letting agents as well as homeowners. You can call 0345 464 0079 or send us an email with the details for a clear quote.
Can you work on commercial sites?
Yes. Hotels, offices and other businesses use us and we are fully insured.
Can you quote for more than one area?
Yes. Just list everything you need.
Do you hold any approvals?
Yes. We’re approved under the ARBOMaster scheme, which is run for the Arbo sealant brand.
Is there a guarantee?
Yes. Every job comes with our 12-month guarantee.
Should I try DIY first?
It depends on the job. Work at height, movement joints, fire-rated gaps and large areas are best left to a professional, while a short indoor joint may be within reach.
How long does external mastic last?
It varies from wall to wall: sunny, exposed elevations and busy joints wear faster. Check them each year and reseal when they split or harden. Every job carries our one-year guarantee.
Work for landlords, hotels and businesses
Whether it’s one flat or a portfolio, the work is the same standard: old sealant fully removed, joints prepared properly and a one-year guarantee.
If you manage several properties in or around Blackmoor, several properties can go on one quote. Just tell us the addresses and what each one needs.
Quotes for external mastic in Blackmoor
Every job gets its own quote. This is what makes a difference:
- The number of rooms or windows
- The number and length of the joints
- Working hours on commercial sites
- Whether the work is at height
A few things move the cost up or down: how much old sealant there is and how stubborn it is, whether mould needs treating, and whether the work is at height. Your quote takes all of that into account.
What to tell us for a quote
When you contact us, these details help:
- Any previous sealing or DIY work
- Where the job is, and your postcode
- Access, such as stairs, a lift or height
- Pictures of the joints, sent by email
Quotes start with a quick conversation. Describe the problem, the location and the size of the job, and we will explain how we’d tackle it. When it suits you, ring 0345 464 0079 or email us.
Looking after it afterwards
So the new joints stay in good condition:
- Clear growth from the base of walls and joints
- Keep movement joints as flexible joints, not mortar
- Walk round the building once a year and look at the joints
- Get split or bare joints resealed while the damage is small
Make sure anyone working on the wall later knows where the movement joints are. They should be kept open and resealed, not filled.
Water getting behind cladding or render can go unnoticed for a long time. By the time there’s a damp patch, the damage can be well established, so it’s worth resealing at the first signs.
Surface by surface
Brickwork movement joints
Vertical joints in long brick walls let the brickwork expand without cracking. We reseal them with a low-modulus sealant over backing rod coloured to suit the wall.
Copings and trims
Metal and stone copings both move with temperature, so the joints need a sealant that stays flexible year round.