You have picked up the keys, walked round your new home and spotted a wonky door, a patchy wall or a scratch on the kitchen worktop. You report it, and back comes the reply: “It’s within tolerance.” If that sounds familiar, you have already met Chapter 9.1 of the NHBC Standards, “A consistent approach to finishes”, even if nobody told you its name.

Chapter 9.1 is the rulebook NHBC and housebuilders use to decide whether the visible finish of a new home is acceptable. It covers almost everything you can see and touch, from brickwork, render, plaster and ceilings to floors, doors, windows, tiling, kitchen units, sealant, paintwork, baths and basins, and even drives and garages. Builders use it to judge their own work, NHBC uses it when inspecting homes and resolving disputes, and buyers can use it too.

One of the most surprising things about Chapter 9.1 is that it tells you where to stand and what light to use. Internal walls, ceilings and paintwork are judged from 2m in natural daylight, with the wall lights switched off and no torch shining across the surface. Brickwork and render are judged as a whole wall from at least 10m away. Kitchen units, worktops, baths and basins are judged much more closely, from just 0.5m. That last point is good news for buyers, because a scratch on a new kitchen door or a chip in a bath is judged far more strictly than a mark on a wall.

The chapter also sets real, measurable tolerances. Internal walls should be flat to within ±3mm under a 2m straight edge, and floors and ceilings should be level within 3mm per metre across rooms up to 6m wide. The gap around an internal door should be no more than 4mm and even, and the gap underneath should be between 10mm and 22mm to the unfinished floor. Neighbouring tiles should not step by more than 1mm where the grout joint is up to 6mm wide.

Our favourite example of how practical the chapter can be is on drives and paths. One hour after rain has stopped, puddles should be no deeper than 5mm or larger than 1m², and there should be no standing water at all next to your front door.

Chapter 9.1 is honest that new homes move and settle as they dry out. Cracks up to 2mm wide where walls meet ceilings and floors, and up to 4mm where the staircase meets the wall, are described as normal shrinkage. The white, powdery efflorescence you may see on new brickwork is described as harmless and generally disappears over time. Knowing this saves you time and lets you concentrate on the snags that really need fixing.

Why it matters to you

For the first two years under NHBC’s Buildmark warranty, your builder is responsible for putting right defects caused by failing to meet NHBC’s requirements. After that, the cover becomes insurance focused on more serious physical damage, so cosmetic issues are best raised early. A defect report that quotes the right clause and measurement, such as “door gap of 7mm exceeds the 4mm maximum in NHBC Chapter 9.1”, is much harder to brush aside than “the door looks a bit off”.

Being told something is within tolerance isn’t always the end of the conversation either. The chapter itself says it is not intended to cover every situation and that discretion should be used, so a highly visible defect can still deserve a repair.

Want the full detail?

We’ve put together a complete Knowledgebase guide to NHBC Standards Chapter 9.1, based on the 2026 edition. It covers every part of the home the chapter deals with, the full set of viewing conditions, a summary table of tolerances, how to raise defects with your builder, the limits of the guidance, and answers to the questions we’re asked most often.

Read our full guide to NHBC Standards Chapter 9.1: A Consistent Approach to Finishes

Let the professionals check for you

Checking a home properly against Chapter 9.1 takes time, the right viewing conditions and the right tools, from a 2m straight edge to a trained eye for detail. Our independent inspectors do exactly that, and every issue in our reports is located, photographed and linked to the relevant standard, ready to send to your builder within two working days. If you’re approaching completion or are within your first two years, get in touch to book your snagging inspection.