What we cannot tell you from here

The 2 things that genuinely need somebody on site

Of the 20 pieces of information a conclusion about concrete tends to turn on, these are the ones no amount of careful description reaches. Not because they are difficult in principle, but because establishing them means measuring, probing or opening something up.

• Void depth and extent. It is the difference between a slab that is unsupported and one that is merely uneven, and it determines whether lifting has anything to push against. Probing, sounding, or drilling test holes. In some cases ground-penetrating survey. All of it requires equipment and access to the slab.
• Subgrade and compaction. Poor compaction produces settlement years later that looks identical to settlement from any other cause, and it changes whether a repair addresses the reason or just the result. Excavation or test holes at the edge, sometimes original construction records where they survive. Frequently it is inferred from the pattern of movement rather than observed directly.

The 18 you can get at yourself

This is the more useful list, and it is the longer one. Most of what separates a vague enquiry from a well-defined one is within reach of somebody with a phone, a tape measure and a rainy afternoon.

• Soil movement (partly). Mark and date the position of an edge or a gap and look again after a wet spell and after a dry one. Two dated observations are worth more than one careful description.
• Drainage. Go out during heavy rain and watch. Photograph where water pools, where it runs and where downspouts discharge. This is the single most useful thing most owners can do.
• Slab thickness (partly). If any edge is exposed — at a joint, a break, or where the slab meets a drain — photograph it with a tape or a coin against it. Do not break concrete to find out.
• Reinforcement (partly). If concrete has already broken and reinforcement is visible, photograph it. Do not create a break to look.
• Crack activity. Draw a line across the crack, write the date beside it, and photograph it. Repeat in a few months. This costs nothing and answers a question nobody can answer from a single photo.
• Vertical displacement. Lay something rigid and straight across the crack and photograph the gap under it, with a tape or a coin in frame for scale.
• Age and history. Write down your best estimate of when it was poured and when you first noticed the problem, and look through old photos of the house. Holiday photographs regularly settle this.
• Previous repairs. Find any paperwork and photograph the patched areas. If a previous repair did not hold, say so — it is useful information, not an embarrassment.
• Freeze exposure (partly). Note whether the affected area stays wet longer than the rest, and whether it is shaded. A north-facing slab that holds water behaves differently from a south-facing one that dries.
• Water source (partly). Note whether the wetness tracks rainfall, irrigation, or neither. Wetness that ignores the weather is worth investigating before anybody quotes concrete work.
• Trees and roots (partly). Photograph what is growing nearby with the slab in frame so the distance is legible, and note anything removed in recent years.
• Joint condition. Walk every joint and photograph any that are open, filled with soil, or have lost their sealant. This is quick and it is frequently where the answer is.
• Use and loading. Say plainly what goes on it, including the occasional heavy thing. A skip delivery two summers ago is relevant and is exactly the kind of detail people leave out.
• Whether damage is surface or full depth (partly). Where material has already come loose, photograph the exposed edge so the depth is visible. Do not chip at sound concrete to find out.
• Finish and sealer history (partly). List anything applied to the surface, including de-icer, and roughly when. Photograph any patchy sheen or peeling.
• Access. Measure your narrowest gate or gap and photograph the route from the street. Mention anything that has to be protected or moved.
• What the concrete adjoins (partly). Photograph where the concrete meets the building, close enough to see whether there is a gap, a sealed joint, or a continuous pour.
• Local requirements (partly). Ask your own municipality directly. We deliberately do not publish permit requirements for any location, because getting one wrong would be worse than not answering.

There is a guide to recording all of it properly — what to photograph, what to measure, and what to write down before anybody visits.

What we will not publish, on purpose

• A price for your project. We explain what moves the number and we do not name one. A figure attached to a project nobody has seen is a guess wearing a decimal point.
• Permit and code requirements for your address. They differ between neighbouring municipalities and change locally. Your own authority answers this directly and for free; we would be guessing, and a wrong answer here is worse than no answer.
• A threshold that makes something serious. No crack width, no slab thickness, no settlement depth. Those vary with mix, reinforcement, subgrade and use, and publishing one would create a standard that does not exist — which people would then quote at contractors.
• A verdict on safety. That is a judgement about a specific structure by somebody qualified who has been there, and it is not something a website can reach.
• A recommendation of a particular contractor. We do not inspect, vet, certify or rank anybody, and we publish no ratings or reviews.

The claims on this page, and what stands behind them

Each of these is something this page says. What follows is why we say it, what we had to assume, and what would change our mind — so you can weigh it rather than take it on trust. How we grade what we publish.

Why this matters

Because the alternative is the position most of this industry takes, which is to imply that a photograph and a postcode are enough. That produces confident answers, some of which are wrong, and a homeowner has no way of telling which.

What homeowners commonly misunderstand about this

• That a limit on remote advice means nothing useful can be done remotely. Most of the work of arriving at a good decision happens before anybody visits. It just is not diagnosis.
• That “needs an inspection” means something is wrong. Plenty of things in that category turn out to be minor once somebody looks.
• That a confident answer is a knowledgeable one. Confidence is free. Ask what the answer depends on and you will learn more from the reply than from the answer.

Questions to ask next

• What did you look at that I could not have seen myself?
• Which part of your recommendation rests on something you measured, and which part on experience?
• What would make you change your mind about this?

Information still needed

Everything on the first list above, for your specific property. Nothing you read here closes any of it, and we are not going to pretend otherwise.

When you are ready, we will help connect you with a contractor who can evaluate your specific situation. If we cannot cover your area, we will tell you that instead of leaving you waiting.