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Insights

Insights & Technical Guides

Clear, practical structural guidance for London property. Our guides explain how structural engineers diagnose movement, when defects need action, and how Building Regulations, surveys and engineering-led repairs work in plain English.

Latest Guides

Structural engineering insights for London property

Honest, engineering-led answers to the questions homeowners, buyers, landlords, businesses and property professionals ask us most often.

New-Build & Snagging

Is My New-Build Wonky? Acceptable Tolerances

Sloping floors and leaning walls: what deviation is normal versus a defect, how it is measured against tolerances, and when it is actually structural.

Basements & Below-Ground

Basement Waterproofing Types Explained

The three BS 8102 methods, tanking, waterproof concrete and drained cavity systems, the dryness grades, and why the design matters more than the product.

Extensions & Foundations

Tying an Extension Into an Existing House

Why extensions crack at the join, how differential movement works, and the key decision: match the foundations and tie in, or keep the new part independent.

Cracks & Movement

Wall Tie Failure and Bulging Walls

Why corroding cavity wall ties crack brickwork in regular horizontal lines and bow walls outward, the signs, and how failed ties are repaired.

Foundations & Ground

Building Foundations Near Trees on Clay

Why foundations near a tree on shrinkable clay must go deeper, the four things that set the depth, and why felling the tree brings its own risk of heave.

Alterations & Repairs

Chimney Breast Removal and Unsafe Stacks

What a chimney breast holds up, how it is supported once removed, the Building Regs and party wall rules, and the 4.5x rule for a leaning stack.

Commercial & Agricultural

Indoor Riding Arenas in the UK: Size, Height and Planning

How to size an indoor school, the clear height most buyers get wrong, why equestrian buildings rarely count as agricultural, and steel vs fabric compared.

Commercial & Agricultural

Salt and Grit Storage Buildings in the UK

Why salt destroys ordinary steel buildings, what a salt store has to do, how push walls should be designed, and steel portal frame vs fabric compared.

Fabric Structures

Portal Frame Buildings: Costs, Uses and the Fabric Alternative

How portal frames work, what drives the cost in the UK, and when an engineered fabric building is the faster, brighter clear-span alternative.

Cracks & Movement

Types of Cracks in Walls and What They Mean

Vertical, diagonal, horizontal and hairline cracks explained with an illustrated guide to what each pattern means and when to worry.

Fees & Costs

How Much Does Subsidence Repair Cost in London?

The four cost stages of subsidence repair: diagnosis, investigation, fixing the cause and underpinning, with 2026 figures and the insurance route.

Fees & Costs

How Much Does a House Extension Cost in London?

Typical 2026 London costs per square metre for single storey, side return and two storey extensions, plus an instant cost calculator.

Fees & Costs

How Much Does a Structural Engineer Cost in London?

Real 2026 fees: advice visits, inspections with reports, wall removal calculations, loft and extension packages, and what moves the fee.

Fees & Costs

How Much Do Basements and Underpinning Cost in London?

Real design-and-build rates: basement construction per square metre, underpinning per metre run, and the factors that move the price.

Loft Conversions

Dormer vs Rooflight Loft Conversions

The four loft conversion types compared, how dormer and rooflight differ, and the structural work each one needs in a London home.

Ground & Site Investigation

Contaminated Land: What You Need to Know

What contaminated land means, the source-pathway-receptor model, and when it affects buying, building or digging a basement.

Retaining Walls

Do You Need a Structural Engineer for a Retaining Wall?

The height where a garden wall becomes an engineering job, plus the drainage, surcharge and planning factors that decide it.

Property Sales

Homebuying Reforms and Pre-Sale Structural Surveys

Why sellers, estate agents and conveyancers may benefit from early structural engineer input where cracks, movement or previous alterations could delay a sale.

Subsidence

Signs of Subsidence in London Homes

How to spot subsidence early, the warning signs that matter and what to do next.

Cracks

When Are Cracks Structural?

How engineers tell harmless settlement cracks from structural cracks that need action.

Foundations

Basement Extension Structural Requirements

Underpinning, retaining walls and waterproofing: the structural design a basement needs.

Structural Engineering

Load-Bearing Wall Removal Explained

Beams, calculations, Building Control and temporary works for removing a wall safely.

Underpinning

Underpinning: When Is It Needed?

When underpinning is genuinely required, when it is not, and the alternatives.

Building Regulations

Do I Need Structural Calculations for Building Regulations?

Which alterations need structural calculations and how Building Control approval works.

Structural Surveys

Structural Survey vs Building Survey

The difference between the two, and which report you actually need before you buy.

Structural Surveys

Trial Pits and Opening-Up Works Explained

Why intrusive investigation is sometimes needed to diagnose foundations and movement.

Structural Repairs

Engineering-Led Structural Repairs Explained

Why repairs should follow diagnosis and a repair specification, not guesswork.

Construction Support

Principal Designer Duties Explained

What the Principal Designer role involves under the CDM Regulations and who needs one.

Our guides span Structural Engineering, Building Regulations, Structural Surveys, Cracks, Subsidence, Foundations, Underpinning, Structural Repairs, Construction Support and Calhoun / Fabric Structures.

Have a structural question of your own?

Send us your drawings, photos, survey concern or project details and we will advise the most practical next step.