A Specific Structural Inspection (SSI) is a structural engineer’s inspection of one crack or one structural defect, followed by a written report explaining what caused it, whether it is still moving and what, if anything, needs doing. It’s the most common structural report for buyers whose survey or mortgage valuer has flagged a single concern. At Lifelys, an SSI costs £570 including VAT, with the report issued within 48 hours of the inspection.

What does an SSI cover?

An SSI focuses on one area of concern. Rather than looking at the whole building, the structural engineer concentrates on the defect you’re worried about and the parts of the structure around it that could explain it.

Typical examples include:

• A crack above a door or window
• A diagonal or stepped crack in a wall
• A bulging or leaning wall
• Movement in a bay window
• Cracking where an extension or conservatory meets the house
• A cracked render panel
• A sagging or cracked lintel

A Victorian bay window with a cracked sill. Bay windows are a common subject for an SSI in Bishopston and Redland, where bay fronted terraces line many streets.

What is an SSI also called?

Different firms use different names for the same report, which can be confusing. You might see an SSI described as a:

• Specific defect report
• Single defect inspection
• Structural engineer’s letter
• Structural survey of one defect

They all mean a structural engineer looking at one specific problem. My guide to the different types of property survey explains how all the surveys and reports fit together.

Who needs a Specific Structural Inspection?

An SSI is right for you if you can point at the problem. The most common situations are:

• Your survey recommends it. A Level 2 or Level 3 survey has flagged a crack or movement for a structural engineer to look at.
• Your mortgage lender asks for it. The lender’s valuer has seen a defect and wants a structural engineer’s report before releasing the mortgage.
• You’ve spotted something yourself. You own the house, or you’re buying it, and one crack or defect is worrying you.
• Your solicitor or insurer has asked for one.

If there are several cracks around the house, or you’re not sure what’s wrong, a General Structural Inspection is usually the better choice. See Specific vs General Structural Inspection for help deciding.

What happens during the inspection?

I visit the property and inspect the defect inside and out. I measure crack widths, check walls for tilt and floors for level nearby, and look for the cause. That might be trees, leaking drains, a failed lintel, roof spread or past alterations.

A fine crack where a conservatory meets the house, a typical single defect inspected during an SSI.

Before I visit, I research the property and the local ground conditions, so I arrive knowing what to look for. The inspection is visual and non-invasive, so nothing is opened up or damaged. You don’t need to be there, but you’re welcome to come and ask questions.

What’s in the structural report?

Your structural report arrives within 48 hours of the inspection, written in plain English with photos. It includes:

• The brief: what I was asked to look at and why
• The property and ground conditions
• What I found, inside and out, with photos
• Discussion: My professional interpretation of what I found (no fence-sitting)
• My conclusions: what caused the defect, whether it’s ongoing and how serious it is
• Recommendations: what to do next

The recommendation usually falls into one of three outcomes: no structural action needed, further investigations to confirm the cause, or a specific repair your builder can quote for.

A wide crack in render, measured and photographed for the report.

What isn’t included?

An SSI focuses on the structure, so it doesn’t cover:

• Damp
• Roof coverings, gutters and roofline
• Decoration and finishes
• Doors and windows
• Services such as electrics, heating and drains
• Parts of the property that can’t be safely accessed

It’s not a condition survey of the whole house, so it doesn’t replace a Level 2 or Level 3 survey. Where more investigation is needed, such as a drainage survey, the report will say so.

How much does an SSI cost?

A Specific Structural Inspection costs £570 including VAT. It’s a fixed fee, so there are no hidden extras, and you’ll know exactly what’s included before you book. You can read more in how much a structural engineer’s report costs.

If the inspection shows the problem is wider than one defect, I’ll tell you rather than leave you with half an answer.

Why choose an independent structural engineer?

I don’t carry out repairs or design work, so I have nothing to sell you after the report. That means my only interest is giving you an honest answer, whether that’s “this is nothing to worry about” or “this needs fixing before you buy”.

About the author
George Lifely is a Structural Engineer (CEng MICE) and AssocRICS surveyor based in north Bristol. He specialises in structural engineer reports for homeowners and buyers, explaining cracks and movement in plain English. He is fully independent, with no repairs or design work to sell.

Get a fixed fee quote

Tell me about the crack or defect, or send me the section of your survey, and I’ll confirm whether an SSI is right for you with a clear, no obligation quote. Get a quote

I inspect homes across north Bristol, including Bishopston, Redland, Cotham, Horfield, Henleaze and Stoke Gifford, as well as the wider Bristol area and beyond. See the areas I cover

Frequently asked questions

What does SSI stand for?
Specific Structural Inspection: a structural engineer’s inspection and report on one crack or defect.

Is an SSI the same as a specific defect report?
Yes. Different firms use different names, but both describe a structural engineer’s report on a single defect.

How long does it take to get the report?
Within 48 hours of the inspection.

Will my mortgage lender accept an SSI?
If your lender has asked for a structural engineer’s report on a specific defect, an SSI is usually what’s needed. Mention the lender’s request when you enquire so the report covers what they need.

What if there’s more than one crack?
If the cracks are related, such as two cracks around the same window, an SSI can often cover them. If there are several separate concerns, a General Structural Inspection is the better choice.ncluding VAT and rises with property size. Both include the site visit, the inspection and the report, with no separate charges.

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