What we cover.
Decarbonisation work is applied to buildings that were designed for none of it. External insulation adds weight and eccentricity, green roofs add substantial saturated load, and roof-mounted renewables concentrate load at fixings. Each needs the existing structure assessing rather than assuming.
- External wall insulation structural support and fixing design
- Green roof and blue roof structural assessment
- Roof strengthening for solar and renewable installations
- Structural assessment for fabric-first retrofit
- Overcladding support structure design
- Structural implications of ventilation and moisture interventions
- Non-traditional construction retrofit assessment
- Load assessment for air source heat pumps and roof plant
What retrofit structural engineering actually involves.
External wall insulation is heavier and more eccentric than it appears, and it has to be fixed back to something that can carry it. On non-traditional construction, and particularly on system-built stock, that backing is frequently not what the drawings suggest. Establishing the substrate before specifying the fixing is the whole job.
Green roofs are a loading question first. A saturated substrate is substantially heavier than a dry one, and the design case is the saturated condition plus snow, not the appearance on a summer afternoon. Many existing roofs will take an extensive system and not an intensive one, and that distinction decides the scheme.
Moisture behaviour has structural consequences that are easy to miss. Insulating a wall changes where the dew point sits, and on a building with embedded timber, a wall plate or bonding timbers, moving that point can put condensation somewhere that causes decay over years rather than weeks.
We check what external wall insulation is actually being fixed back to, particularly on system-built stock where the backing is rarely what the drawings claim, and we assess green roofs for the saturated case plus snow rather than the dry weight. Where insulation moves the dew point onto embedded timber, we say so before it is installed.
Does external wall insulation need structural design?
The support and fixing does. The insulation itself is not heavy in isolation, but it is applied eccentrically over a large area and has to be anchored back to the existing wall. On non-traditional and system-built construction the backing material is frequently not what the drawings show, so establishing the substrate comes before specifying the fixing.
- Designs checked and signed by a Chartered Structural Engineer
- Substrate established before fixings specified
- £5m professional indemnity cover
- Moisture and decay risk considered, not just load
The codes behind retrofit structural engineering.
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.
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.
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.
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 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.
Real structures, surveyed and engineered.
Common questions
Can our roof take a green roof?
It depends on the saturated load, which is considerably higher than the dry load. Many roofs take an extensive system and not an intensive one, and that assessment usually decides the specification.
Do you assess non-traditional housing for retrofit?
Yes. System-built stock has known and specific behaviours, and identifying the construction type is the first step before any fixing is specified.
Do you assess roofs for heat pumps and plant?
Yes. Roof-mounted plant adds concentrated load and vibration, and it is worth assessing before installation is booked.
Can you work alongside a retrofit coordinator?
Yes. We cover the structural elements and coordinate with the wider retrofit design team.
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05Contractor SupportOn-site engineering, engineer of record
06Renewable Energy StructuralSolar, wind, storage, EVTell us what you are building.
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