What to do with my windy floor space

[WabbitPoo]

At a loss as to know what to do now...

short(ish) story: 1950s build rendered house, on the North coast of Wales (so pretty windy!)...wind whistling in floor space between ground and first floor, hence carpets are all cold and draughts whistle out of every possible corner of the upstairs (eg pipe entries, under the bath, etc etc).

I have filled in every nook and cranny I can find on the oiutside that might be letting wind in. The loft is very windy so I guess the wind is getting in between the slates, and then down the cavities. I can't get to the cavities due to the slope of the roofs.

Short of ripping out all upstairs floors and filling with insulation, what can I do about this to make the house a bit less, well, windy? I had thought of lifting the carpets upstairs and laying down a layer of polythene under the underlay to stop the draughts, but I figured the cold air would still be cooling down the floors so not much to be gained from that.

I could use sealant along all the edges and any gaps in the floorboards, but many of them are damaged (by assorted plumbers over the years) so this isn't really practical.

Any ideas as to what I can do?

 

[KenGMac]

WabbitPoo, hi

As an off the wall consideration?

How about you look at the air bricks at the base of the external walls?

Hypothetically considering your descriptions, is it possible that the air bricks [I hope there are some fitted, if not this load of typing is a load of breeze] are not installed to modern standards, that being, the outer air brick should be sleeved across the cavity? A generally purpose made clay insert should prevent air from the outside air brick entering the entire cavity and not being channelled into the under build area.

If the above is correct??? then the wind around the house could be being allowed to get into the cavity, not the under building area?

From time to time, if you shine a really bright torch into the external air brick, there is a possibility that you may, or may not see a, best described as a, clay tunnel, if you can see brick on the outer and inner surface of the bricks then the air entering the external air vent is simply entering the cavity.

Result is that, the so called "over pressure" within the cavity, engendered by wind blow entering the external air bricks will seek out and find any small crevise or opening at say first floor level or indeed into the loft if the cavity wall is not sealed at that level.

WabbitPoo [love that handle] can you please tell the board of your finding please? remember, you will need to carefully inspect every external air brick, even one without the cavity air brick closure can cause problems?

Ken.

 

[JohnD]

you can stuff mineral wool insulation (no need to do the whole floor) tightly along the external walls. Where the joists are built into the brickwork is very often gappy, and although it is possible to inject expanding foam into the crack, it is much easier to stuff wool into, say, the first foot nearest the wall between the joists. You will often be able to do this by only taking up one floorboard. Where the joist runs parallel to the wall, it is less likely to be draughty, but you can poke the wool in, torn into small strips, with a batten. Fill the gap completely.

It will also stop the black line of dust and dirt which often impregnates the edge of the carpet next to the skirting.

BTW, if you are using mineral wool, look for the variety treated with Ecose. The name is marked on the wrapper, and the wool is brown, not yellow. It does not shed irritant dust and fibres. It is sold as several own-brands, and under the Knauf brand.

 

[Doggit]

Do you have any underlay under the carpets? I've done the mineral wool bit under the floorboards, and it's not too bad a job. Unfortunately, you have to cut the insulation into strips to fit between the joists, but you only need to lift 2 boards every 4 feet or so apart, or however far you can get you arm underneath from each side. It not only makes the rooms warmer, but cuts down noise travelling between floors.

 

[WabbitPoo]

thanks to all for the advice. Solid floors downstairs so no air bricks at that level. The 3 at the upper levels had already been sealed completely, presumably when previous occupants had cavity fill blown in (woolly pellets)

 

[WabbitPoo]

Well, after the recent storms and cold weather I'm back to this issue.....

Is CWI in a rendered seaside house a stupid idea? The concept would, at least in theory, sort out my problem once and for all.

 

[KenGMac]

Wabbitpoo good evening.

Very recent post on the board.

Suggest you have a look??

Cavity wall insulation .......
Discussion in 'Building' started by gasbanni, 1 Dec 2017.



Read more: https://www.diynot.com/diy/threads/cavity-wall-insulation.493504/#ixzz50z1YQHuJ

Ken.

 

[Doggit]

In Wales, there are so many reports of CWI being wrongly installed, because the amount of rain that soaks the walls, then goes across the insulation to the inner walls. I think there is a grading system for different areas that warns you where not to install it.

 

[KenGMac]

This CWI thing keeps bubbling up in several places, such as what appears to be on-going in Wales.

As an aside you should see some of these older installations in Scotland??

As Doggit there is a sort of a scale, based on wind speed and hence driving rain as I recall a scale of 0-4 in the post I copied there is a reference to this and in it some areas CWI is simply not advised ?

In general terms it is a real Cowboy Industry

bottom line is beware, and do the research as to what type of CWI you adopt, even then get as many written guarantees as you can, then get them backed up

Ken

 

[Doggit]

Have you considered external wall insulation. It'll cover all the holes that let in draughts, and warm the place up far better than CWI.

 

[Pickup66]

I had an issue with cold air seeping under my flooring ( the wife wanted a new laminate floor) I used ESS insulating tape before starting and I ran it around the whole room and in the gaps on the floorboards and it did the trick. But later i found cold air coming from the gap between the laminate and the wall so I ran the tape around the gaps and the difference was amazing and my wife noticed the difference in the room straightaway. Hope that helps.

 

[WabbitPoo]

Thanks for the advice. I'd prefer to cut off the wind at source (ie prevent it getting into the cavities) but I cant get to them in the loft due to the slope of the roof. Is it usual to leave the topes of the cavities open like this? My loft is pretty windy due to the wind getting between the welsh slates. Maybe I can seal them somehow eg spray foam?

 

[KenGMac]

WabbitPoo, good evening.

In general terms cavities should be sealed, this includes [obviously] at loft level, the reason is that if the cavity is un sealed then thermal movement will occur within the cavity and heat loss will ensue.

I was told that a sealed cavity will have still air contained within it, this still air is a fairly good thermal insulation profile, but a vented cavity negates all of that, think of a sealed double glazing unit.

Question? is there any under slate roof felt under the Welsh slate?

Ken.

 

[tony1851]

Thanks for the advice. I'd prefer to cut off the wind at source (ie prevent it getting into the cavities) but I cant get to them in the loft due to the slope of the roof. Is it usual to leave the topes of the cavities open like this? My loft is pretty windy due to the wind getting between the welsh slates. Maybe I can seal them somehow eg spray foam?

A windy loft is a healthy loft.

 

[KenGMac]

Just a further consideration??

Provided there is a really good air flow within the loft space and you are not relying on Eaves vents, you may think about introducing a small amount of Glass Wool into the space directly above the open ventilated cavity, it should be possible to shove some glass wool into this location ans undertake this task remotely, that is using a pole or similar?

Ken.