Can't identify draughts in house

[Harvey119]

Hi, moved into new house late last year and have noticed that whenever it's really windy, there will be a lot of wind in between the ceiling of first floor and floor of second floor.

Thought the house was built in late 90s, but now think it was the 80s.

This presents itself as wind coming under the bath through the hole they have made in the floor under the bath, making a strong breeze come from under the bath and making the bath panel move and make noises.

No idea where the wind could be coming from and would appreciate help to locate it.

I have already had a ladder out and filled in a couple of small holes around the air pipe, but now can't find any other holes anywhere!

Have included a picture of under the bath where the wind is, the back of the house which shows the air pipe and is also where the side of the bathroom is that has the hole where the wind comes from and also a side picture. Many thanks

 

[JohnD]

lift the floor and pack mineral quilt loft insulation between the joists. Pack very thoroughly around the edges of the room and under the skirting where draughts commonly blow in. I strongly recommend the grade treated with Ecose, which does not shed irritant dust or fibres. It will be marked on the wrapper. It is brown, not yellow.

If you see any actual gaps, you can fill them with sand and cement mortar (if in brickwork), or with pink fire-grade expading foam. There is often a gap where plasterboard meet wall. If the house is very badly built, or has had replacement doors and windows fitted badly, there may be gaps between the wall and the frames.

Cover electrical cables, lighting fittings etc before using foam, brush or vac away dust, mist with water to help it grip and set.

You seem to have a huge number of holes in your walls for pipes and cables. Unusual in a modern-looking house. Quite likely they all have gaps, and the air will blow around in the cavity if there is no CWI.

Green or white marks on the walls and pipes indicates leaks or splashes.

plumbers are equipped with axes, chainsaws and sledgehammers to make holes in walls, floors and ceilings.

 

[foxhole]

Pack hole under bath with rock wool, should stop any drafts.Any holes in floor around sink waste? Toilet outlet?