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Structural Roof Loading Appraisals

Before anything is added to a roof, somebody has to establish what it can carry and how much life the covering has left. We assess both, report them separately, and design the strengthening where capacity is short.

What we cover.

Roof loading appraisal is one of the things we do most. Colleges, theatres, distilleries, industrial units, stadia and hotels have all needed the same two questions answered: what will this structure take, and what condition is it actually in.

Structural roof loading appraisal reports
Roof condition surveys
Existing roof structure capacity assessment
Assessment for solar PV, plant and screening
Wind uplift and snow loading assessment
Purlin, rafter and truss capacity checks
Strengthening design where capacity is short
Consistent reporting across an estate or portfolio

In detail

What structural roof loading appraisals actually involves.

Capacity and condition

Capacity and condition are separate questions and we report them separately, because conflating them produces the wrong decision. A roof can be structurally adequate with three years of covering left, or in good condition and unable to take the load being proposed. Only answering both tells an owner what to do.

Where drawings do not exist

Most buildings have no usable structural drawings, and many have been altered since they were built. So the assessment starts by establishing what is actually there: member sizes, spacings, bearing conditions, timber or steel condition, and any previous modification. Working from records that do not match the building is the commonest way these assessments go wrong.

When capacity is short

Where capacity is short, that rarely stops the project. It usually means specific members need strengthening, the load needs relocating away from a weak zone, or the fixing arrangement needs changing to spread it differently. We design that rather than simply reporting a failure.

Where we have done this

We have delivered this across around twenty commercial sites, including further education colleges, a theatre, a distillery, manufacturing and industrial premises, a football stadium and a hotel, reporting to a consistent format so buildings within an estate can be compared.

How Lead Group helps

We establish what is actually there where no usable drawings survive, report capacity and condition as separate questions because conflating them produces the wrong decision, and design the strengthening or the relocation where capacity is short. Across a portfolio we report to a consistent format so buildings can be compared against each other.

How we work

What is the difference between a roof condition survey and a structural appraisal?

A condition survey tells you the state of the covering and how much serviceable life it has. A structural appraisal tells you what the structure beneath it can carry. They answer different questions and they can disagree: a sound structure under a failing covering, or a good covering over members that will not take additional load. Where a decision depends on both, we issue both.

Designs checked and signed by a Chartered Structural Engineer
Capacity and condition reported separately
£5m professional indemnity cover
Consistent format across a whole estate

Not sure what you need?Send us your drawings, or just a photograph of the wall. We will tell you what is required and what it costs before you commit to anything.

Get a quote 020 3432 4186

Standards & codes

The codes behind structural roof loading appraisals.

Eurocodes 0-9 & UK National Annexes

BS EN 1990 through BS EN 1999 govern the basis of design, actions, and the design of concrete, steel, timber, masonry and aluminium structures. Every calculation we issue references the relevant Eurocode part and its UK National Annex, and states which parts were applied.

Analysis, design & drafting software

Structural analysis and design in Tekla Tedds and Tekla Structural Designer, with Autodesk Robot, CSC Fastrak, CSC Portal Frame, MasterSeries and Hilti Profis used where a scheme suits them. Drawing production in AutoCAD, and modelling in Autodesk Revit where a project is delivered in BIM. Output is issued as readable calculations rather than raw software printouts, so a checker or a building control officer can follow the reasoning.

Approved Document A (Structure)

The Building Regulations requirement your local authority Building Control checks against. Our calculations and drawings are prepared to demonstrate compliance so your submission is accepted without back-and-forth.

Professional indemnity insured

Every report and calculation package is backed by professional indemnity cover, which is what lets a lender, Building Control or another engineer rely on it.

From the job record

Issued drawings, redacted.

More drawings →

Roof structure layoutRedrawn as vector line work with the entire text layer discarded, so no title block, client name or address exists in the file.

Scope of an inspection. Inspections are carried out within the scope and limitations set out in the fee proposal and stated in the report. Unless expressly agreed otherwise, an inspection covers what is reasonably accessible at the time and is not a warranty that every defect, deterioration or concealed condition has been identified. Where something cannot be seen, we say so and set out what would establish it.

Process

From enquiry to sign-off.

Enquiry

Send drawings or describe the problem. We confirm the scope, the deliverables and a target timescale.

Information

We agree the survey, drawings or data we need and any site access required.

Engineering

Design, calculation or assessment to the relevant Eurocodes and UK National Annex.

Issue

A clear, defensible report or set of calculations, with assumptions and limitations stated.

Selected work

Real structures, surveyed and engineered.

All work →

Sport and recreationCharlton Athletic FC, The ValleyTwo steel monopitch stand roofs rising to 27 metres were assessed for a proposed solar PV installation. Both were cleared to carry the arrays as they stand, and the fragile roofs were surveyed entirely by drone with nobody working at height.

Read →

Manufacturing and industrialWienerberger, Tamworth

EducationCarlisle College

Film and mediaDragon Studios, Pencoed

Questions

Common questions

Can you assess a roof with no drawings?

Yes, and that is the usual situation. We survey what is actually there rather than working from records that may not reflect the building as altered.

Do you assess for solar specifically?

Yes. Solar adds permanent load, changes wind uplift behaviour and concentrates load at fixings, so it needs assessing against the existing structure before installation is specified.

Can you report across a portfolio?

Yes. Reporting to a consistent format is what lets sites be compared and a programme built by priority rather than by whoever asked most recently.

What if the roof will not take the load?

We design the strengthening, or set out the alternatives: relocating the load, changing the fixing arrangement, or phasing the work. A negative answer on its own is not a useful deliverable.

Do you use drone survey for roof inspections?

Where it is the safest and most complete way to see a roof, yes, alongside physical inspection of the structure beneath it.

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