Foundation Discussion Preparation Checklist

Gather every drawing you hold of the existing building and note which ones show anything below floor level, as those are the first documents an engineer will ask about.

Below-ground information is rare in domestic paperwork, so knowing whether you have any at all shapes what has to be established on site instead.

Write down what you know about when each part of the building was constructed and whether it has been extended, since the answer often differs across the plan.

Buildings put up in stages frequently sit on different foundations at different points, and the engineer needs to know where those changes occur.

Ask who is commissioning any ground investigation, what form it would take on a site of this kind and how the findings reach the designer.

What investigation is appropriate is a decision for a qualified engineer or specialist; ask the question and record the answer rather than deciding yourself.

Note the relationship between internal floor level and external ground at each side of the building, described simply as a step up, a step down or roughly level.

This tells an engineer something about how the existing walls meet the ground, and it is one of the few things an owner can record accurately without tools.

Record what you actually saw the last time a hole was dug anywhere on the plot, including whether water appeared, how fast it filled and what the sides looked like.

Owner recollections of a soakaway trench or a post hole are anecdotal, but they often direct the engineer towards the right first question.

Ask what the engineer needs from the architect or designer before starting, so you understand which conversation has to happen first and who is waiting on whom.

Foundation advice usually follows a layout, and instructing consultants in the wrong order leaves one of them idle and the other guessing.

Walk inside and outside and photograph every crack you can find, noting where it begins, where it ends and whether it runs through mortar joints or through the brick itself.

Where a crack travels matters more than how wide it looks, and an engineer can read a clear photograph far better than a verbal description.

Write the date beside each photograph and repeat the exercise after a long dry spell and after prolonged rain, so any change becomes visible rather than remembered.

Whether something is changing is usually more informative than its current appearance, and only a dated sequence can show that.

Note doors and windows that stick, latch badly or have been packed, planed or re-hung, and write down whether that has always been the case in your time there.

Adjusted joinery is a quiet record of past movement, and previous owners rarely leave any other trace of it.

Record any sloping floor, gap opening above a skirting or separation between a bay and the main wall, describing exactly where you stood when you noticed it.

Locating an observation precisely lets a professional look at the same thing rather than hunting for what you meant.

Ask a qualified professional to interpret everything you have recorded, and deliberately avoid reaching your own conclusion about what is causing it.

Cracking has many possible causes and only a qualified engineer or surveyor should attribute it; nothing an owner observes proves or rules out foundation movement.

Gather any earlier report, correspondence or repair record relating to movement, including work carried out by previous owners and anything referenced in your purchase survey.

Where a property has an insurance history relating to movement, discuss it with your insurer and a qualified professional before any work is planned.

List the trees and large shrubs within sight of the building, note the species where you know it and describe roughly how close each stands to the nearest wall.

Distance and species are the two things an engineer or arboriculturist will ask for first, and an owner can supply both without any equipment.

Write down anything you know about trees felled on the plot in the past, including stumps still in the ground and roughly where they stood.

A tree that is no longer there can still be part of the discussion, and nobody except the owner or a neighbour is likely to remember it.

Note whether any boundary hedge is mature and well established, and record whether it belongs to you, to a neighbour or to nobody in particular.

Ownership determines who can decide anything about it, which matters if the hedge becomes part of the foundation conversation.

Ask a qualified professional how nearby vegetation and any past removal bear on the foundation discussion for the soil found on this particular site.

The interaction between trees, soil and foundations varies enormously with ground type; treat it strictly as a question for a qualified engineer.

Photograph the trees while in full leaf and record roughly how far the canopy reaches relative to the building, using a fixed feature as a reference.

Canopy extent is far harder to judge in winter, so a photograph taken at the right time of year saves an argument about scale later.

Record whether you intend to remove, plant or heavily prune anything substantial as part of the project, since that belongs in the same conversation.

Owners often treat landscaping as a separate later job, which is precisely how a significant change gets made without anyone technical hearing about it.

Protection status can restrict pruning and felling; ask the local authority what applies to these particular trees before any of it is planned.

Note every drain cover, gully and rodding point inside or close to the proposed footprint, and photograph each one before anything is stripped or moved.

These features vanish early in the works, and a photograph with something recognisable in shot is often the only surviving record of where they were.

Ask who will establish what drainage runs beneath the proposed foundations, how it would be traced and at what point that information is needed.

Building close to or over an existing drain normally involves the drainage authority; confirm locally what applies rather than assuming it can be designed around.

Write down where the incoming water supply enters the building and roughly what route you believe it takes across the plot from the boundary.

Supply pipes are often unrecorded, laid at unknown depth and discovered by a machine bucket, so any owner knowledge is worth capturing.

Record whether the property has ever had a cellar, coal store, service pit, well or buried fuel tank, and mark on a sketch where you believe it was.

A suspected buried tank or void must be handed to qualified specialists; do not attempt to locate, open or assess anything of the kind yourself.

Note any old wall line, path edge or slab visible at the surface within the footprint, including changes in how the grass grows across it.

Buried remnants show as dry lines or sinking patches, and pointing them out early is more useful than finding them halfway through a dig.

Ask what happens to the existing foundations of anything being demolished, who decides whether they remain and how that decision gets recorded.

Leaving old footings in place is sometimes proposed and sometimes ruled out, and owners are frequently surprised that it was a decision at all.

Write down which parts of the existing building the new work will physically touch, and photograph each junction from inside and from outside.

Identifying the contact points precisely helps the engineer ask targeted questions instead of general ones about the whole building.

Ask how the junction between old and new construction is intended to behave over time, and record the answer in the professional's own words.

How new and existing construction interact is an engineering matter; note what you are told and do not paraphrase it into a conclusion of your own.

Note whether the existing wall at each junction appears solid, cavity or something you genuinely cannot tell from looking, and say so honestly rather than guessing.

An honest gap in your knowledge is more useful than a confident wrong answer, because it tells the professional what has to be opened up or investigated.

Record the position of any airbrick, vent or underfloor void near the proposed work, and note whether the floor sounds hollow when walked on.

Ventilation paths to a suspended floor are easy to block accidentally with new construction, and reinstating them afterwards is awkward.

Ask who is responsible for supporting the existing structure while the junction is formed, and how that support is planned and managed.

Temporary support of an existing building is designed and controlled by qualified people; ask who holds that responsibility and leave the detail entirely to them.

Write down which internal finishes near the junction you accept will be disturbed and which you want protected or carefully removed for reuse.

Original mouldings, tiles and floorboards near a junction disappear quickly unless somebody has said in advance that they matter.

Note how close the proposed work comes to any structure standing on a neighbour's land, including garages, extensions, conservatories and boundary walls.

Proximity is the trigger for several separate conversations, and measuring it roughly yourself tells you which of them are likely to apply.

Ask a qualified professional what has to be established about neighbouring foundations before work near them is planned, and who is responsible for doing that.

Obligations towards adjoining owners differ by location and circumstance; confirm what applies to your site with a qualified professional before relying on anything.

Record who owns each boundary feature, gather whatever paperwork describes the arrangement and note where the documents disagree with what is on the ground.

Boundary paperwork and physical reality diverge surprisingly often, and the discrepancy is better found now than during a difficult conversation later.

Write down whether a neighbouring building appears to have been extended or altered, based only on what is visible from your own side of the boundary.

Alterations next door can be relevant to work close to the line, and observing from your own property keeps the exercise entirely uncontroversial.

Note where a neighbour's downpipe, gully or waste pipe discharges near the boundary, and whether water from it crosses onto your ground.

Water arriving from next door is a recurring complication in work along a boundary, and raising it before excavation is far easier than afterwards.

Decide and record how and when you want to approach neighbours about work close to their property, and who will actually have that conversation.

Leaving this undecided usually means a neighbour first learns about the project from a notice or a machine, which sets a tone that is hard to recover.

Ask how a difference in ground conditions would be identified on site, who would be informed first and how a decision would then be reached.

Knowing the chain of communication in advance means you are not learning it for the first time while a machine stands idle.

Write down what you want to happen before any change to the foundation approach is carried out, including who must confirm it in writing and to whom.

This is one of the few genuinely owner-side decisions in the whole subject, and stating it early is far more effective than objecting afterwards.

Ask how a change of this kind is instructed and recorded under your arrangement, and who is actually entitled to give that instruction.

How variations are instructed is a contractual matter; take advice from a qualified professional rather than accepting an informal explanation on site.

Agree who has authority to pause the work while advice is sought, and record that a decision taken at trench level is very difficult to revisit afterwards.

The pressure to keep going is real, and naming the person who can stop it removes the awkwardness from doing so.

Record which parts of the design would be affected further along if the foundation approach changed, so the consequences are understood before a choice is made.

Foundation changes often ripple into levels, thresholds and drainage, and those effects are easier to weigh when they have been listed in advance.

Ask what records of the completed foundation work you should expect to receive, and where they should be kept once the project is finished.

Ask the engineer and the local building control body what records they expect at this stage rather than assuming any particular document will be issued.