How to survey a building for draughts

What do I look for when visiting properties? I am not a building surveyor so, as I walk in through the front door, I note the presence or absence of draught strips, letter plate seals, weather bar, locks. Moving further in, I cast an eye towards any holes round radiator pipes, gaps in floorboards and/or under skirtings.

Upstairs I check the loft trap for draught proofing strips and note whether it is insulated or not. In the loft I look for daylight. It is acceptable to see daylight when looking down through ventilation slots but not upwards through roof coverings. Is insulation present or absent, how thick is it, are there gaps or bits missing. Are the cistern and pipe work including the overflow insulated? Then, is there a draughty gap around where the soil pipe or other pipes go down into the house?

Bathroom: is there a fan, can the window be left open in a secure position to provide background ventilation when needed.

Bedrooms: are there any gaps under window boards or round the window frames. Are the window sashes draught proof. Old air vents. Gaps under skirtings, these can be draughty even upstairs! See first floor void

Airing cupboards, gaps round pipes, old pile holes that have not been filled or covered going up into the loft.

Back downstairs now:

Living rooms, old air vents, gaps under skirtings, round heating pipes. Draughts under window boards, round windows, are casements draught free, do windows shut properly, do trickle ventilators close. If there is a chimney is it used sometimes or unused? If the chimney is not used then fit a chimney balloon or shove an old pillow in a poly bag up it.

In the kitchen are there holes round pipes leading to outside, redundant ventilation grilles, draughty window or back door. Does the fan or cooker hood have a back draught flap or shutter?

Most of the repair issues that I come across are outside: gutters, down pipes, rendering, pointing, woodwork, fences, paths and steps. I have occasionally identified Health and Safety concerns: wobbly steps, dangerous guttering, pipes or swans necks falling off the wall, fences in poor states of repair, trip hazards on paths.