Is it normal.....

[WabbitPoo]

...for the wind to whistle in from behind a light or plug socket? We have a 1950s cavity-walled house. It has had woolly stuff blown in at some point in the past as insulation.

We live in N Wales and have get a lot of strong winds, and I have been on the hunt for draughts armed with some clear sealant and too much time on my hands. I noticed today for the first time that many of our sockets emit strong draughts, and I wish to eliminate them. Any idea what to do about it?

 

[jeds]

If it's a true draught it must be getting into the socket box somehow. Turn the power off at the CU and take a socket face off to see how the boxes are fixed - and if the cables are run in conduit.

 

[kazuya]

seen it before with studded walls, but not with brick

 

[JohnD]

I'd suspect that the hole for the backbox was clumsily made, and penetrated through to the cavity.

If it was me I would remove the backbox and use mortar to repair the broken blockwork (you can put cardboard or similar through the hole and brace it forward with string to prevent your mortar falling down the cavity, then mortar the backbox back in. It is a fiddly job but not difficult. If you are DIYing the time spent has no cost. Vacuum away any dust first, and moisten the blocks with a water spray.

It is also possible to use expanding foam, but I believe the ordinary stuff in cans can hold water or damp in a cavity. Anyway it should be kept away from contact with cables.

You must of course turn off the power and test for dead before you start work, and not restore it until the job is safe.

 

[^woody^]

It would certainly be unusual if it whistles Good King Wenceslaus.

 

[theprinceofdarkness]

If you have a gale blowing out of your power point then this gale is also blowing around in your cavity (of the wall ). So you are living in a single brick skin house.
The thing to do is to walk around your property to find out where the air leaks are. One favorite place is air bricks that have not been sleeved properly, around window and door frames, waste pipes. . . Once all of these have been attended to, the tops of your cavities need to be stuffed with glass fibre if they have not been done.
Much better then just sealing the back of power points, because the ends of your joists buried in the wall at the ceiling/ floor level will need to done next.
Frank

 

[WabbitPoo]

thank you all. the wind whistles from all sorts of places eg from under the bath (in fact anywhere connected to the under-floor areas upstairs (solid floors downstairs)

so in summary I shouldnt have wind in me cavities, then?

 

[JohnD]

that might be because the brick or blockwork is carelessly done, with gaps not filled with mortar. This is very common on the inside leaf. Plastering covers up the gaps, but not under the floors or in the loft. Take a look (the loft will be easiest) at the quality of build. if the joists are built into the walls there is usually a gap.

Your cavity fill ought to have muffled the draught, but perhaps it has settled or blown out. You may find heaps of cavity fill that has escaped though gaps.

You may also find a black dust stain in the edges of the carpets.

 

[kazuya]

seen it before with studded walls, but not with brick

Adding more Loft insulation cured the one I was talking about

 

[WabbitPoo]

what normally happens at the top of the whole cavity wall? should there be a closer of some sort between the inner and outer leaf?

 

[noseall]

I have come across this many times and have commented upon it on here.
We combat this effect (when dabbing boards) by applying a solid bead of dab around the board perimeter as well as solid vertical intermediate dabs and also a solid dab around all back boxes etc.

Here's our latest job....

Dabbing

• noseall
• 12 Dec 2015

 

[WabbitPoo]

not clear how that helps if the wind is coming from within the leaf and the back boxes breach the cavity.....? Anyway, in my case I need t address why there's so much wind moving thru the cavoty...cant be normal!

 

[noseall]

not clear how that helps if the wind is coming from within the leaf and the back boxes breach the cavity.....? Anyway, in my case I need t address why there's so much wind moving thru the cavoty...cant be normal!

No, I agree with what you are saying, but the phenomenon is recognized. We would bed our back boxes in dabbing material so that they were air tight.

 

[^woody^]

so in summary I shouldnt have wind in me cavities, then?

Some older properties are designed with vented cavities.

Anyway, you dont get wind in the cavity, just some different air pressure and a gap allowing air movement.

It's very common for an enthusiastic sparks and a big SDS chisel to crack the back of a box recess, or a mortar joint at the recess not to be filled.

Use mastic or caulk to fill gaps, or fit a self adhesive intumescent patress liner

 

[seasickstevie]

Are you sure you're not living next door to Roger Whittaker?





I'll get my coat