Penzance · Cornwall
Extension pulling away repairs in Penzance
Rear and side extensions are common across Penzance, and so is the crack where new meets old. Usually it reflects the two parts sitting on different foundations, and the first question is whether the gap is still opening.
Guide price from£620per junction inc VAT
- Postcodes
- TR18
- Population
- about 20,000
- Area
- Cornwall
- Pricing region
- South West
Is Cornwall prone to ground movement?
Penzance (TR18) has around 20,000 residents and sits in Cornwall. We also take enquiries from nearby Camborne (12 miles), Redruth (16 miles) and Falmouth (21 miles).
Most of Cornwall is on firmer ground than the clay belts of the south-east. Old metal-mine shafts and workings are recorded in places, so mining searches are routine for some properties. What you mostly find across Cornwall: granite and slate-stone cottages, cob buildings, Victorian terraces and post-war estates.
What to expect when we carry out extension pulling away repairs
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.
Is it time for extension pulling away repairs? Common signs
- Mastic or render at the joint repeatedly splitting open
- A vertical crack or gap where the extension meets the house
- Daylight or draughts showing through the internal corner joint
What should you budget for extension pulling away repairs in Penzance?
Guide prices below are for homes in Penzance, on South West 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. | £620 – £2,050 | per junction |
| Movement joint and making goodest. | £410 – £1,250 | per junction |
| Underpinning the extension where needed | £1,050 – £2,600 | per metre of wall |
Repair options we may recommend
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
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
Rules for extension pulling away repairs in England
In England, underpinning and other work that alters or strengthens a wall or foundation is building work under the Building Regulations (Part A, structure), so building control approves and inspects it. Like-for-like repairs often are not, and we tell you which applies before a price is agreed. Work to a party wall, or excavation close to a neighbour’s foundations, can also need a notice under the Party Wall etc. Act 1996.
Your extension pulling away repairs questions
How much will extension pulling away repairs cost in Penzance?
Guide prices for extension pulling away repairs in Penzance start from about £620 per junction, including VAT, on South West rates. Your fixed written price follows photos or a survey and depends on the extent of the work and access.
Do you cover Penzance?
Yes, Penzance is covered, along with postcode districts TR18. We also cover nearby Camborne and Redruth.
Is the ground in Cornwall prone to subsidence?
Cornwall is mostly granite and slate with little shrinkable clay, so clay subsidence is less common than in the south-east. Historic tin and copper mining has left shafts and workings in places such as Camborne and Redruth, and mining searches are routine there. 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.
Other structural repairs in Penzance
- Gable end wall repairs
- Bowing wall repairs
- Crack stitching
- Underpinning
- Subsidence insurance claim repairs
Extension pulling away repairs near Penzance
Call about the cracked extension junction at your Penzance property; a free initial assessment first, then a fixed written price once the repair is specified.