Plain English on hard subjects.
Articles from the Corvus team on what we do and how. Written by surveyors and engineers, edited for the people who'll have to commission, manage, or interpret the work.
For drilling contractors
GPR scanning before drilling, why it matters
Why pre-drill GPR scanning is cheap insurance on a UK construction site, and what happens when it is skipped.
Read article
How to plan a safe drilling programme
Drilling into reinforced concrete is routine work that becomes dangerous when shortcuts are taken. Here is how to plan a drilling programme that is safe, defensible, and on programme.
Read article
How to prepare a site for GPR scanning
Practical preparation for a GPR scan: surface condition, access, programme integration, and the questions you'll be asked before the surveyor arrives.
Read article
What happens on the day of a Corvus survey
A practical, minute-by-minute account of what a Corvus survey day looks like from arrival to debrief, written for the site manager who needs to know what to expect.
Read article
The insurance case for pre-drill scanning
Drilling without a scan is not just operationally risky, it creates liability exposure that can affect how insurers treat a claim. Here is what the insurance picture actually looks like.
Read article
CDM regulations and concrete scanning, the principal contractor's responsibilities
CDM 2015 places duties on principal contractors to manage pre-construction information, including the location of buried services and structural reinforcement. Here is where scanning fits.
Read article
Post-tension cables, the hidden danger in concrete floors
Post-tension cables are common in modern UK floors and among the most dangerous things to hit in a slab. How they work, how to find them, and why scanning before drilling is essential.
Read article
GPR scanning for car park decks
Car park decks are some of the hardest-working concrete structures in the UK. Here is what GPR finds in them, why they need regular inspection, and what a survey involves.
Read article
Detecting post-installed fixings and anchors with GPR
Post-installed fixings and chemical anchors can be invisible from the surface but are critical to locate before drilling or coring nearby. Here is how GPR finds them.
Read article
Scanning for underfloor heating pipes and embedded services
Drilling through an underfloor heating pipe is an expensive and disruptive mistake. Here is how GPR locates embedded pipes and services before any core is taken.
Read article
Void detection using GPR, finding cavities under slabs
GPR is a well-established tool for finding voids under concrete slabs, beneath roads, and in the sub-base. Here is how it works and what the results look like.
Read article
Slab thickness measurement with GPR
Knowing the thickness of a concrete slab is fundamental to structural assessment, drainage design, and reinstatement work. Here is how GPR measures it and how accurate it is.
Read article
GPR for floor slab condition surveys
A GPR floor condition survey goes beyond reinforcement mapping, it can indicate delamination, voids, and deterioration without breaking out a single tile or screed. Here is what is involved.
Read articleFor structural engineers
Cover depth surveys, what the data tells a structural engineer
A cover depth survey produces numbers. Here is what a structural engineer does with those numbers and how to brief a survey so the data is actually useful downstream.
Read article
Understanding concrete cover depth
Why cover depth matters, how it is specified, how it is measured non-destructively, and what to do when it is wrong.
Read article
What are rebar chairs and why does cover depth matter
Rebar chairs are the small unsung component that helps protect the durability of reinforced concrete. Here's how they work, what goes wrong, and how cover-depth surveys catch the problem.
Read article
How to interpret a ferro scan report
What a ferro scan report contains, what each section means, and what to look for when the data has to inform an engineering decision.
Read article
How to read a GPR scan report
What to look for in a GPR scan report, what each section means, and the questions to ask the surveyor before you accept the work.
Read article How to write a concrete scanning brief
A good brief produces a better survey. Here is exactly what to include when commissioning a concrete scanning survey, scope, access, drawings, deliverables, and programme.
Read article
Structural assessment using NDT, a complete guide
How non-destructive testing supports structural assessment of existing buildings: methods, scoping, deliverables, and the engineer-surveyor relationship.
Read article Working with structural engineers, a guide for contractors
Practical advice on commissioning surveying and NDT work in coordination with a structural engineer, what they need, when, and how to brief everyone effectively.
Read article What is ferro scanning in construction
Ferro scanning explained: what it does, how it works, and when it is the right tool for reinforcement mapping and cover-depth measurement on UK construction work.
Read article
GPR vs X-ray concrete scanning, a comparison
GPR and X-ray are both used to image the interior of concrete. Here is when each method is the right choice, and why X-ray is far less common on UK sites than people expect.
Read articleFor housing associations
The Building Safety Regulator in 2026: what changed and what it means for landlords
In January 2026 the Building Safety Regulator left the HSE and became a standalone body with its own enforcement powers. What the regulator does, what changed, and what building safety managers and social landlords should expect.
Read article
What is a building safety case? A plain-English guide for building safety managers
Every occupied higher-risk building must have a safety case: a live body of evidence showing that fire and structural risks are understood and managed. A practical guide for building safety managers, housing associations and social landlords.
Read article
LPS blocks and the Building Safety Regulator: what structural evidence you actually need
Large panel system blocks are under specific scrutiny from the Building Safety Regulator. What social landlords and building safety managers need to evidence about LPS structures, and how that evidence is gathered in occupied homes.
Read article
Safety case reports and missing as-built records: closing the evidence gap
A safety case report must describe how a higher-risk building is constructed and evidence its structural condition. When the as-built records are missing or unreliable, structural investigation is how building safety managers close the gap.
Read article
NDT and GPR for housing associations and social landlords
Why non-destructive testing suits housing associations, and how to integrate scanning and testing into a planned maintenance programme.
Read article
Scanning in occupied buildings, what you need to know
Scanning while a building is live changes the logistics entirely. Here is how to manage access, noise, dust, and programme when the site is not yours to shut down.
Read articleLondon jobs
Concrete scanning for basement conversions
What you need to know about scanning existing concrete slabs and walls before a basement conversion or underpinning project starts.
Read article
Scanning basement slabs and retaining walls
Basement structures present specific GPR challenges: damp concrete, restricted access, and complex geometry. Here is how scanning is approached and what it typically finds.
Read article
GPR, scanning, and the Party Wall Act
Party wall work often requires investigation of the existing structure before any notifiable work begins. Here is where scanning and NDT support the party wall process.
Read article GPR scanning for retail and commercial fit-outs
Fit-out contractors regularly drill into slabs they know nothing about. Here is what a pre-drill scan involves in a retail or commercial environment and what it typically finds.
Read articleBuying a scan
How to choose a concrete scanning company in the UK
Practical advice on choosing a UK concrete scanning company: qualifications, equipment, deliverables, and the questions that separate good from cheap.
Read article How to commission a concrete scanning survey
A practical guide to commissioning a concrete scanning survey: brief, scope, deliverables, and the questions to ask before signing the quote.
Read article
Understanding your scanning quote, what each line item means
A scanning quote is not just a day rate. Here is what each line item typically covers, what is often left out, and how to compare quotes that look different on the surface.
Read article
What certifications should a GPR scanning company have
The certifications, accreditations, and competencies that distinguish a defensible GPR scanning company in the UK.
Read article
GPR scanning costs in the UK, what to expect
An honest guide to UK GPR scanning costs. Day rates, project rates, what affects the price, and how to specify scope to control budget.
Read article How long does a GPR survey take
An honest answer on how long a GPR survey takes, from a short pre-drill scan to a multi-day campaign on a complex site.
Read article GPR vs ferro scanning, which do you need
A side-by-side guide to GPR and ferro scanning. What each one does well, what each one does badly, and how to choose for your job.
Read article What is in a Corvus report
What you get from a Corvus scan: marks on the slab before we leave, a signed report and CAD plan within 5 working days, and the limits stated plainly. Plus what to check on any surveyor's deliverable.
Read article
The credentials that matter in scanning and testing
CSCS, ProQual, PAS 128, UKAS, EuroGPR, insurance: which credentials matter when you commission concrete scanning, utility surveys or concrete testing, and how to check them in a minute.
Read articleHow it works
What is GPR concrete scanning and when do you need it
GPR concrete scanning explained in plain English: what it is, what it shows, and when you need it on a UK construction site.
Read article
How does ground penetrating radar work
A plain-English explanation of how ground penetrating radar works, what it can detect, and why it is the tool of choice for non-destructive construction surveys.
Read articlePAS 128 and utilities
PAS 128 explained, the standard for utility surveys
PAS 128:2022 is the British specification for finding and recording buried utilities. Survey types, quality levels, methodology and how to specify a survey to it.
Read article
What is utility mapping and why is it important
Utility mapping locates the buried services that an excavation or piling job has to avoid. Here is how it is done, what the deliverable looks like, and why it is non-negotiable.
Read articleConcrete testing
What is a pull-out test and when is it required
Pull-out testing for in-situ concrete strength explained: what it does, how it works, and when it is the right test for your project.
Read articleRebound hammer testing, a guide
Rebound hammer testing is fast, cheap, and useful, within its limits. Here is how it works, what it tells you, and how to use the data well.
Read article
Concrete core sampling, what it involves
Concrete core sampling extracts a cylinder of in-situ concrete for laboratory analysis. Here is how it is done, what it tells you, and how to commission it well.
Read article
Compressive strength testing of concrete
Compressive strength is the headline number for any concrete pour. Here is how it is measured, where the numbers come from, and what to ask for in the deliverable.
Read article
Concrete condition surveys, a complete guide
A concrete condition survey combines visual inspection, NDT, and sometimes sampling to build a picture of how a structure is performing. Here is how one is scoped and delivered.
Read articleLiDAR
What is LiDAR scanning in construction
LiDAR scanning explained: what it is, what it captures, and why it is widely used for as-built surveying in UK construction.
Read article
LiDAR scanning for measured building surveys
Measured building surveys have been transformed by LiDAR. Here is what a LiDAR-based measured survey captures, how it compares to traditional tape-and-sketch, and what the deliverable looks like.
Read articleWhat is a point cloud survey
A practical guide to point cloud surveys for construction: what they are, what they capture, and how to use the data downstream.
Read articleHow to specify a LiDAR survey deliverable
Many problems with LiDAR surveys come from a poorly written brief. Here is exactly what to specify, accuracy, format, coordinate system, deliverable, so the data is usable when it arrives.
Read article