Cwmbran · Gwent
Extension pulling away repairs in Cwmbran
If the corner joint in your Cwmbran 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
- NP44
- Population
- about 49,000
- Area
- Gwent
- Pricing region
- Wales
What is the ground like in Gwent?
Cwmbran is in Gwent and takes in postcode districts NP44. About 49,000 people live there. Neighbouring towns we cover: Pontypool (3 miles), Risca (5 miles) and Newport (5 miles).
Gwent has a mix of ground, with clay in some places and firmer rock in others. Historic coal workings are recorded beneath parts of Gwent, and a coal mining search is worth checking where movement is unexplained. Housing stock in Gwent: Valley terraces on steep hillsides, Victorian houses in Newport and Abergavenny, and post-war estates.
What to look for before calling about extension pulling away repairs
- A vertical crack or gap where the extension meets the house
- Mastic or render at the joint repeatedly splitting open
- Extension roof flashing lifting off the original wall
Extension pulling away repairs prices in Cwmbran
Guide prices below are for homes in Cwmbran, on Wales rates and including VAT. A survey or good photos let us turn them into a fixed written price.
| 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 |
How we usually approach 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
What happens during extension pulling away repairs, step by step?
Find what is moving
An independent chartered structural engineer can inspect, and we can arrange one. A drain survey under the extension, a trial pit at its footing and tell-tale monitoring across the joint are common checks before choosing the repair.
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.
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.
Questions about extension pulling away repairs in Cwmbran
How much will extension pulling away repairs cost in Cwmbran?
Guide prices for extension pulling away repairs in Cwmbran 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 Cwmbran?
Yes. We take enquiries from across Cwmbran, including NP44, and from nearby places such as Pontypool and Risca. Send photos for a free initial view and we will tell you what happens next.
Is the ground in Gwent prone to subsidence?
The valleys of Blaenau Gwent, Torfaen and Islwyn lie on the South Wales coalfield with extensive historic workings and spoil tips, while Newport and Monmouthshire have Mercia Mudstone, alluvium and Old Red Sandstone. 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.
Can I just fill the gap with mastic?
Mastic can keep water out short term, but it does not stop movement or reconnect the walls. If the gap reopens after filling, something is still moving. Photograph and measure it over a few months first, so an engineer can see the trend.
Other structural repairs in Cwmbran
- Gable end wall repairs
- Lintel replacement
- Resin injection ground stabilisation
- Boundary and garden wall repairs
- Wall tie replacement
Extension pulling away repairs near Cwmbran
Call about the cracked extension junction at your Cwmbran property; a free initial assessment first, then a fixed written price once the repair is specified.