Aberdare · Mid Glamorgan
Extension pulling away repairs in Aberdare
If the corner joint in your Aberdare extension keeps splitting after you fill it, something is still moving. Measuring the gap over a few months, with dated photos, gives an engineer the evidence to recommend the right repair.
Guide price from£550per junction inc VAT

- Postcodes
- CF44
- Population
- about 31,000
- Area
- Mid Glamorgan
- Pricing region
- Wales
What should you know about the ground under Aberdare?
We cover Aberdare and its postcode districts CF44, part of Mid Glamorgan, with a population of roughly 31,000. Nearby places we cover include Mountain Ash (4 miles), Rhondda (4 miles) and Merthyr Tydfil (4 miles).
Mid Glamorgan has a mix of ground, with clay in some places and firmer rock in others. Historic coal workings are recorded beneath parts of Mid Glamorgan, and a coal mining search is worth checking where movement is unexplained. Housing stock in Mid Glamorgan: Long stone and brick terraces on valley sides, Victorian houses in Bridgend and post-war estates.
Guide prices for extension pulling away repairs in Aberdare
For Aberdare we use Wales rates. Treat the table as a budget guide, inc VAT; the price you pay is the one on your written quote.
| Item | Guide price | Per |
|---|---|---|
| Junction crack repair with stainless tiesest. | £550 – £1,850 | per junction |
| Movement joint and making goodest. | £370 – £1,100 | per junction |
| Underpinning the extension where needed | £920 – £2,300 | per metre of wall |
Methods for extension pulling away repairs
Movement joint and making good
Where some seasonal movement is expected to continue, the junction is formed into a proper flexible movement joint with a compressible filler and sealant, so the two parts can move without cracking. Flashings and internal finishes are detailed to suit.
Best for: Minor ongoing movement that does not threaten the structure
Underpinning the extension
If the extension is still dropping because its footings are too shallow or on poor ground, they are taken deeper by mass concrete, beam-and-base or mini-piles. The engineer designs the scheme, and the junction is repaired once the new foundation is in.
Best for: Active movement from shallow footings, roots or soft ground
From first photo to finished repair
Show us the junction
Send photos of the crack outside, the internal corner and any flashing above, with a measure for scale. We give a free initial assessment and an initial view on whether the gap is likely old or still opening.
Choose the fix
The engineer decides between ties, a movement joint or underpinning. We confirm a fixed price in writing once the repair is specified, covering the junction, flashings, internal finishes and any foundation work.
Finish and hand over
Internal corners are replastered, skirtings and coving refixed, and doors or windows in the extension eased where the movement affected them. Records of the repair and any approvals are passed to you.
Symptoms that point to extension pulling away repairs
- Daylight or draughts showing through the internal corner joint
- A vertical crack or gap where the extension meets the house
- Floor level dropping where the extension and house floors meet
Rules for extension pulling away repairs in Wales
In Wales, the Welsh version of the Building Regulations applies. Underpinning and other work that alters or strengthens the structure needs building control approval and inspection; like-for-like repairs often do not. The Party Wall etc. Act 1996 applies to work on party walls and excavation close to a neighbour’s foundations.
Frequently asked questions
How much will extension pulling away repairs cost in Aberdare?
Guide prices for extension pulling away repairs in Aberdare start from about £550 per junction, including VAT, on Wales rates. Your fixed written price follows photos or a survey and depends on the extent of the work and access.
Do you cover Aberdare?
Yes, Aberdare is covered, along with postcode districts CF44. We also cover nearby Mountain Ash and Rhondda.
Is the ground in Mid Glamorgan prone to subsidence?
Mid Glamorgan lies on the South Wales coalfield, with dense historic workings, spoil tips and steep valley sides. Landslip, retaining walls and mining legacy are all live issues in the valleys. Only an investigation can say why a particular building has moved.
Who is responsible if a recent extension is moving?
If the extension is recent, the original builder, the designer or building control records may be relevant, and you may have rights against the builder. Gather the plans, completion certificate and contract. Insurance often excludes defects in new construction, so check your policy.
Can a drain under my extension cause it to move?
Yes, a cracked or displaced drain beneath or beside an extension can soften clay or wash away fine soil. A CCTV drain survey usually finds it. Repairing the drain is often the first and most important step before any repair to the walls.
Other structural repairs in Aberdare
- Structural surveys and crack monitoring
- Boundary and garden wall repairs
- Resin injection ground stabilisation
- Lintel replacement
- Gable end wall repairs
Extension pulling away repairs near Aberdare
Send photos of the extension junction at your Aberdare home, inside and out, and we will give a free initial assessment and a guide price.