Wall Tie Replacement Costs UK — What to Charge for Cavity Wall Tie Repairs in 2026

What Wall Tie Failure Actually Is

In a cavity wall, the inner and outer leaves of masonry are tied together with metal wall ties bedded into the mortar joints. Those ties stop the outer leaf bowing away from the building and share wind loading between the two leaves. In properties built from roughly the 1900s to the 1980s, the original ties were usually galvanised mild steel, and the zinc galvanising was often thin. Over decades, that coating fails and the steel corrodes.

The problem isn't just that a corroded tie stops doing its job. As mild steel rusts it expands — corroding steel can occupy several times its original volume. A tie sitting in a mortar bed jacks the joint open as it rusts, lifting the brickwork course by course. Because ties sit at regular intervals, this produces the classic symptom: horizontal cracking at consistent vertical spacing up the wall, often most visible on exposed gable ends. In advanced cases you get bulging or bowing of the outer leaf, expansion at the verges, and what the trade simply calls "tie failure".

How It's Diagnosed

You cannot price this work honestly off a customer's description of "some cracks". Proper diagnosis comes first, and a survey is a billable part of the job. The standard approach combines a metal-detector scan to locate the existing ties (confirming their position, spacing and whether whole rows are missing) with a borescope inspection through a small drilled hole into the cavity. The borescope lets you see the actual condition of the embedded ties and the state of the cavity — debris, mortar snots bridging the gap, or ties already failed flush with the inner leaf.

The diagnostic tells are characteristic: regular horizontal cracking at tie-row spacing (commonly around every fourth or sixth course), oxide staining bleeding from the bed joints, and stepped or vertical cracking at corners and openings where the expansion concentrates. Survey fees in the UK typically run £150–£400 depending on property size and whether a written structural report is required for a mortgage lender or buyer.

Quick Reference: Wall Tie Replacement Prices UK 2026

These are guide figures for 2026. Wall tie replacement is almost always priced per tie installed, then access, isolation and making good are added on top. Always confirm tie count from the survey before committing a fixed price.

Tie Types and Replacement Methods

The replacement tie you choose affects both your material cost and your fitting time, and different cavity conditions call for different systems. The three families you'll work with are:

Mechanical Expansion Ties

A stainless steel tie inserted through a drilled hole and then mechanically expanded — the body grips both leaves as it's set. Fast to install and reliable in sound masonry. The workhorse remedial tie for most jobs in good brick or block.

Resin-Bonded / Grouted Ties

A tie set into a perforated sleeve and bonded with resin or cementitious grout. These suit weaker, friable or perforated masonry where a mechanical tie wouldn't get a secure grip — the resin spreads load over a larger area. Slower to install and more material cost, but essential in poor substrates.

Helical / Driven Ties

A helical stainless steel tie driven through a pilot hole, gripping by friction along its threaded profile. Quick and tidy in suitable masonry, and the same helical bar technology underpins crack stitching, so the two repairs often run on the same job.

Whichever system you use, it should be a CE-marked / UKCA-marked remedial tie installed to a defined density. New ties go into the brickwork, not into the old failed bed joints — you set the replacement pattern to current standards rather than simply matching whatever the builder originally used.

Tie Density and Spacing

Remedial ties are installed to a density that meets current standards rather than the original (often sparse) builder's pattern. As a working rule the trade installs in the region of two to three ties per m² across the general wall area, with extra ties around openings, at verges, reveals and movement joints where loading concentrates. This is why a job is priced per tie but estimated from wall area: you measure the elevations, apply the density, add the perimeter and opening allowance, and that gives you the tie count to quote against.

Under-specifying density to win a price is the fastest way to a callback and a failed insurance-backed guarantee. The density is part of the engineered solution, not a place to trim the number.

Isolation of Old Ties and Making Good

New ties carry the load, but the old corroded ties are still in the wall and still expanding. Where corrosion is active, those ties must be isolated — typically cut, sleeved or otherwise relieved so they can no longer jack the bed joints open as they continue to rust. On a wall with significant ongoing corrosion this is a real part of the labour and should be a costed line, not an afterthought.

Then there's making good. The fitting process leaves drill holes, and the original failure usually left cracked, displaced or oxide-stained mortar. You repoint the affected joints, fill and colour-match the drill holes, and rake out and repoint any cracked beds so the finished elevation looks sound. In severe cases where the cracking has propagated through the masonry, crack stitching with helical bars bedded into raked-out joints is added to re-tie the cracked sections back together. Making good and any stitching are separate from the per-tie rate.

What Drives the Cost

Two jobs with the same wall area can land far apart on price. The main cost drivers are:

• Number of ties: the headline variable — quote off the surveyed tie count, not a guess. A few hundred ties for a typical semi, more for a detached.
• Wall area and elevations: more elevations and more openings mean more ties and more perimeter allowance.
• Access and scaffolding: single-storey gable work may need a tower; full two- or three-storey elevations need proper scaffold, which is a significant separate cost.
• Wall construction: sound brick takes a mechanical tie quickly; weak, friable or perforated masonry forces resin-bonded ties, slowing the job and raising material cost.
• Isolation of old ties: where corrosion is active, isolating the failed ties adds labour per tie.
• Making good: repointing, hole filling, colour matching and any crack stitching all add to the base per-tie figure.

Because access dominates multi-storey jobs, always quote scaffolding as a separate line. Customers understand it's a third-party cost, and itemising it stops you being undercut by an operator who has skipped safe access.

What's Included in a Proper Quote

A quote that wins the right jobs — and protects your margin — should spell out exactly what the customer is buying. As a minimum, include:

• The diagnostic survey and a written report identifying tie positions and condition
• The number of replacement ties, the tie type, and the installed density
• Isolation of corroded original ties where required
• Making good — repointing, drill-hole filling and colour matching
• Any crack stitching needed where cracking has propagated through the masonry
• Access and scaffolding as a clearly separated line
• The guarantee — ideally an insurance-backed guarantee — and what it covers

Worked Example: A Typical Semi-Detached

Take a 1930s two-storey semi-detached with a corroding gable and front elevation showing horizontal cracking at tie spacing. The survey (£250) confirms galvanised steel ties failing across both elevations. You measure the elevations, apply a density of roughly two to three ties per m² plus perimeter and opening allowances, and arrive at around 300 replacement ties.

At a blended rate of around £12 per tie supplied and fitted, that's roughly £3,600 for the ties. The original ties on the worst elevation are actively corroding and need isolating, and there's repointing and hole filling across both elevations. Scaffolding for the two-storey gable and front is quoted separately by your scaffolder. The all-in figure for the per-tie work and making good lands comfortably inside the £1,500–£4,000 whole-house guide band, with scaffolding itemised on top. A larger detached property, or one needing crack stitching as well, pushes into the £4,000–£8,000+ range.

Practical Pitfalls to Avoid

• Skipping proper diagnosis: never price off visible cracks alone. Survey first with a metal detector and borescope so you know the tie count, the masonry condition and whether crack stitching is also needed. Guessing the count is how you lose money.
• Cutting tie density: install to current standards using a CE-marked / UKCA-marked system. Under-specifying density to undercut a rival voids the guarantee and invites a callback.
• Leaving corroded ties active: if badly corroded original ties aren't isolated, they keep expanding and re-crack the wall even after new ties are fitted. Cost and carry out isolation where corrosion is live.
• Vague guarantees: clients — and their mortgage lenders and buyers — expect a long-term guarantee, usually an insurance-backed guarantee that survives if your firm ceases trading. Be explicit about the term and what it covers, because for many customers the guarantee is the product.
• Forgetting making good: the customer judges the job on the finished elevation. Build repointing, hole filling and colour matching into the price rather than discovering them as unpaid extras on the day.