Gorseinon · West Glamorgan
Extension pulling away repairs in Gorseinon
For many Gorseinon homes, the extension was added decades after the house was built, on concrete that never matched the original footings. Where that difference causes movement, a designed movement joint or a deeper foundation is the usual fix.
Guide price from£550per junction inc VAT

- Postcodes
- SA4
- Population
- about 21,000
- Area
- West Glamorgan
- Pricing region
- Wales
What should you know about the ground under Gorseinon?
With roughly 21,000 people, Gorseinon spans postcode districts SA4 in West Glamorgan. Neighbouring towns we cover: Llanelli (5 miles), Swansea (5 miles) and Clydach (6 miles).
Clay soils are found in parts of West Glamorgan. Historic coal workings are recorded beneath parts of West Glamorgan, and a coal mining search is worth checking where movement is unexplained. Housing stock in West Glamorgan: Hillside terraces, Victorian villas in Swansea and post-war estates.
Symptoms that point to extension pulling away repairs
- Mastic or render at the joint repeatedly splitting open
- A vertical crack or gap where the extension meets the house
- Extension roof flashing lifting off the original wall
Guide prices for extension pulling away repairs in Gorseinon
Prices in Gorseinon are worked out on Wales rates. They include VAT and are a starting point: access, the extent of the damage and whether an engineer or building control is involved all move the figure.
| 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
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
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
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.
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.
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.
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 should I budget for extension pulling away repairs in Gorseinon?
Guide prices for extension pulling away repairs in Gorseinon 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.
Can you survey a property in Gorseinon?
Yes. We take enquiries from across Gorseinon, including SA4, and from nearby places such as Llanelli and Swansea. Send photos for a free initial view and we will tell you what happens next.
Why do houses in West Glamorgan crack?
Swansea and Neath Port Talbot lie on the South Wales coalfield, with historic workings, tips and steep valley sides, and softer estuarine ground around the docks. Only an investigation can say why a particular building has moved.
Will my extension need underpinning?
Often not. Many separating extensions are fixed by repairing a drain, tying the junction or forming a movement joint. Underpinning is for extensions that keep dropping because their footings are too shallow or the ground beneath is poor, as shown by monitoring.
Is it normal for an extension to crack at the join?
A fine crack at the junction is fairly common, especially in the first few years as a new extension settles. It becomes a concern when the gap is widening, tapering, letting in water or matched by sticking doors and sloping floors. Those signs point to continuing movement.
Related work in Gorseinon
- Chimney stack repairs
- Structural surveys and crack monitoring
- Subsidence insurance claim repairs
- Bay window subsidence repairs
- Lintel replacement
Extension pulling away repairs near Gorseinon
Share the loss adjuster’s schedule for your Gorseinon extension claim, and we will price the junction repair and making good to it in writing.