The Healthy Homes draught stopping standard, explained
Draught stopping is the cheapest standard to meet, the fastest to prove, and the one with the most immediate payoff: heat you paid for staying in the room it was made for. The requirement is to block unreasonable gaps and holes that let draughts in, around windows, doors, floors, ceilings and walls, and to close off open fireplaces that are not in use.
What "unreasonable" means in practice
Houses need some air exchange, the standard is not asking for a sealed box, and the ventilation standard requires openable windows precisely so airing is deliberate rather than constant. The gaps that fail are the ones you can feel on a cold evening: daylight under an exterior door, a rattling sash window, a hole where pipework enters, gaps between old floorboards over an open subfloor. If a candle flame bends near it on a still night, it is on the list.
The fireplace rule
An open fireplace that is not being used as heating must be closed off, an open chimney is a permanent extraction fan for warm air. Blocking the flue and sealing the opening is routine work, but note the interaction: if the fireplace is the tenancy's heating, it is not "unused", and if it is closed off, do it in a way that can be reversed if a future tenancy wants it back in service. Record which choice was made and when.
An afternoon's work, mostly
Most draught stopping is foam tape, door seals, brush strips, gap filler and a few hours. The skill is in the audit, not the fix: walk the house on a cold, windy day with the heating on and your hand out. Old villas and cottages will have a longer list, but even there the materials bill is usually small compared with any other standard.
Evidence worth keeping
This standard has the simplest evidence pattern of the five: a dated before-and-after photo pair per fix, and a one-line note of what was sealed. A fireplace closure deserves its own photo and date. Filed against the property, that record signs the draught-stopping line of a compliance statement by itself.