Cardiff · South Glamorgan
Extension pulling away repairs in Cardiff
An extension pulling away from a Cardiff house is often a drain problem, a shallow footing or a missing tie-in, rather than a failing building. Finding out which applies decides whether the fix is a junction repair or new foundations.
Guide price from£550per junction inc VAT
- Postcodes
- CF10, CF11, CF24
- Population
- about 370,000
- Area
- South Glamorgan
- Pricing region
- Wales
What is the ground like in South Glamorgan?
We cover Cardiff and its postcode districts CF10, CF11, CF24, part of South Glamorgan, with a population of roughly 370,000. Neighbouring towns we cover: Penarth (3 miles), Caerphilly (7 miles) and Barry (7 miles).
South Glamorgan has a mix of ground, with clay in some places and firmer rock in others. Ground movement here is more often linked to soils, drains and trees than to mining. Typical buildings in South Glamorgan: Victorian terraces in Cardiff and Penarth, inter-war semis and post-war estates.
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
Junction crack repair with stainless ties
The open joint is cut out, stainless ties or helical bars are fixed across it into both the old and new masonry, and the joint is repointed or rendered to match. Inside, the corner is replastered. This suits extensions that moved once and have since stopped.
Best for: Settled extensions with a stable gap at the junction
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.
Repair the junction
Drains are repaired first if they are leaking. The joint is then tied, formed as a movement joint or rebuilt after underpinning, with roof flashings reset so the junction stays watertight. Building control is handled where needed.
Symptoms that point to extension pulling away repairs
- Patio doors or windows in the extension starting to bind
- Extension roof flashing lifting off the original wall
- A vertical crack or gap where the extension meets the house
Guide prices for extension pulling away repairs in Cardiff
For Cardiff 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 |
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
What is the price of extension pulling away repairs in Cardiff?
Guide prices for extension pulling away repairs in Cardiff 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 carry out extension pulling away repairs in Cardiff?
Yes, Cardiff is covered, along with postcode districts CF10, CF11, CF24. We also cover nearby Penarth and Caerphilly.
Does the ground around Cardiff cause cracking?
Cardiff is built on Mercia Mudstone, river gravels and alluvium, and the Vale of Glamorgan on Lias limestone and clay. Soft alluvium near the rivers and docks can settle. Only an investigation can say why a particular building has moved.
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.
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.
More repairs we carry out in Cardiff
- Subsidence repairs
- Subsidence insurance claim repairs
- Wall tie replacement
- Underpinning
- Bay window subsidence repairs
Extension pulling away repairs near Cardiff
Send photos of the extension junction at your Cardiff home, inside and out, and we will give a free initial assessment and a guide price.