is it easy to handle kingspan K7 for attic insulation?

Markus9

Hi,

I wanted to replace the earthwool between joists with K7. Is it easy to do or maybe it's too difficult to cut?

Thanks

listermint

Why specifically?

Markus9

because it's old and I have to refurbish it, so I was thinking of a different solution

listermint

Very expensive solution tbh. How old is it ? Why does it need to be replaced why not just top it up you don't generally remove it for toping up

Lumen

K7 is for pitched roofs. K3 is for floors, but over rather than between. AFAIK phenolic is specified when you are trying to preserve headroom. Fitting boards between joists is going to be a PITA and you'll need to fill the gaps, whereas earthwool fits properly without faffing.

Markus9

Then I'll opt for sheep wool, thanks!

Lumen

Markus9 wrote: »

Then I'll opt for sheep wool, thanks!

Yeah, that's what I thought until I got a price for it!

Calahonda52

Markus9 wrote: »

Hi,

I wanted to replace the earthwool between joists with K7. Is it easy to do or maybe it's too difficult to cut?

Thanks

why not supplement what is there with cellulose
eg
https://www.ecologicalbuildingsystems.com/Ireland/Products/Product-Detail/Cellulose-Insulation

Markus9

Calahonda52 wrote: »

why not supplement what is there with cellulose
eg
https://www.ecologicalbuildingsystems.com/Ireland/Products/Product-Detail/Cellulose-Insulation

This looks interesting, thanks!

I know that sheep wool is expensive but the attic is small and I don't like the fact that I need to wear a mask to handle earthwool, that's not a good sign...

Lumen

Markus9 wrote: »

This looks interesting, thanks!

I know that sheep wool is expensive but the attic is small and I don't like the fact that I need to wear a mask to handle earthwool, that's not a good sign...

You also have to wear a mask with cellulose.

listermint

Markus9 wrote: »

This looks interesting, thanks!

I know that sheep wool is expensive but the attic is small and I don't like the fact that I need to wear a mask to handle earthwool, that's not a good sign...

The mask youd have to wear anyway regardless of what you buy because your attic will be full of dust, Its not a nice place to work in.

Ive recently put earthwool in mine 56 bales of it (big attic double layer) and it is easy to work with didnt even need gloves tbh. But wore a mask for the dust.

Earthwool was very easy to work with. The Fibreglassesque stuff that was under it still had its horrible itchy nonsense after 3 decades. Thats stuff is horrible.

Calahonda52

The proper way to do this is, at the eves to use a ventilation baffle
eg
http://www.contractortechproducts.com/durovent_baffle.html

The only way it can be done properly, IMO, is to strip off the first meter of slates and felt, fit the ventilation baffles, replace felt and slates, sleeve all power cables for air cooling and then blow cellulose in to fill all nooks and crannies.

listermint

Calahonda52 wrote: »

The proper way to do this is, at the eves to use a ventilation baffle
eg
http://www.contractortechproducts.com/durovent_baffle.html

The only way it can be done properly, IMO, is to strip off the first meter of slates and felt, fit the ventilation baffles, replace felt and slates, sleeve all power cables for air cooling and then blow cellulose in to fill all nooks and crannies.

Hes working between the joists ... Not the roof trusses

Markus9

listermint wrote: »

Markus9 wrote: »

This looks interesting, thanks!

I know that sheep wool is expensive but the attic is small and I don't like the fact that I need to wear a mask to handle earthwool, that's not a good sign...

The mask youd have to wear anyway regardless of what you buy because your attic will be full of dust, Its not a nice place to work in.

Ive recently put earthwool in mine 56 bales of it (big attic double layer) and it is easy to work with didnt even need gloves tbh. But wore a mask for the dust.

Earthwool was very easy to work with. The Fibreglassesque stuff that was under it still had its horrible itchy nonsense after 3 decades. Thats stuff is horrible.

Ok so, would you suggest to keep that **** there? Because I have the yellow itchy fibreglass there at the moment. Better to remove it or leave it there and topup with earthwool or sheep wool?
Thanks for the help

listermint

Markus9 wrote: »

Ok so, would you suggest to keep that **** there? Because I have the yellow itchy fibreglass there at the moment. Better to remove it or leave it there and topup with earthwool or sheep wool?
Thanks for the help

Leave it where it is.and top it up.

It's the common method.

Lumen

I removed a skip-load of the yellow stuff last week. Nasty job but only took an hour or so. You can get cheap protective gear from builders merchants.

I'll be replacing with earthwool, after I can summon the energy to go back up with a vacuum cleaner and tidy up.

GreeBo

I topped up an attic with the recycled plastic bottle rolls from B&Q (usually 2 for 1 during summer sales!)
It's easy to use, easy to cut, doesn't itch or irritate and doesn't burn.

Calahonda52

listermint wrote: »

Hes working between the joists ... Not the roof trusses

Have a closer look at the diagram please.

For the hard of hearing, the purpose of the baffle is to deflect the air from the soffit board up beyond the CEILNG insulation and stop it passing through the CEILING insulation, leading in many cases to mould along the edge of the ceiling.
See image

GreeBo

Calahonda52 wrote: »

Have a closer look at the diagram please.

For the hard of hearing, the purpose of the baffle is to deflect the air from the soffit board up beyond the CEILNG insulation and stop it passing through the CEILING insulation, leading in many cases to mould along the edge of the ceiling.
See image

Is it not to allow the attic space to breathe?

Markus9

thanks everyone for taking the time to give your advice

Markus9

is isover like earthwool or is it nasty as well?

Calahonda52

GreeBo wrote: »

Is it not to allow the attic space to breathe?

More to control the airflow that is implicit in any house that has ventilated soffit boards or similar
http://www.greenbuildingadvisor.com/articles/dept/musings/site-built-ventilation-baffles-roofs

listermint

Calahonda52 wrote: »

Have a closer look at the diagram please.

For the hard of hearing, the purpose of the baffle is to deflect the air from the soffit board up beyond the CEILNG insulation and stop it passing through the CEILING insulation, leading in many cases to mould along the edge of the ceiling.
See image

For the hard of reading no one asked about ventilation channels into the soffits.

At all.

GreeBo

Calahonda52 wrote: »

More to control the airflow that is implicit in any house that has ventilated soffit boards or similar
http://www.greenbuildingadvisor.com/articles/dept/musings/site-built-ventilation-baffles-roofs

Yeah, ventilation of the attic, like I said?

Lumen

I think BryanF suggested terminating with membrane wrapped batts to achieve the same effect with batt insulation as vent baffles do with loose fill, i.e. controlled ventilation of the rafters without blowing cold air through the joist insulation.

edit: apparently not

BryanF

Don’t think I did..

Lumen

BryanF wrote: »

Don’t think I did..

Sorry, I must have misremembered. I'm not sure where I read the suggestion, maybe it was this:

https://www.boards.ie/vbulletin/showpost.php?p=61462922&postcount=10

sinnerboy wrote: »

Haven't done this - but you could make "sausage rolls" 300mm diameter made up of Tyvek wrapped around rockwool . And squeeze between the joist into the attic floor cavity over the wall plate .

Firestop , windcheat + thermal continuity

muffler

Lumen wrote: »

Sorry, I must have misremembered. I'm not sure where I read the suggestion, maybe it was this:

https://www.boards.ie/vbulletin/showpost.php?p=61462922&postcount=10

That's a quote from a completely different poster and was obviously posted a long time ago in a completely different thread. I'm not sure why you would do this.

Lumen

muffler wrote: »

That's a quote from a completely different poster and was obviously posted a long time ago in a completely different thread. I'm not sure why you would do this.

Because it's related to the same issue, detailing of insulation at edge of the attic.

I am not sure why you find it objectionable.

muffler

Lumen wrote: »

Because it's related to the same issue, detailing of insulation at edge of the attic.

I am not sure why you find it objectionable.

Well first of all you misquoted another poster or at least indicated he said something that he hadnt. Then you bring a post from somewhere else which really isnt the thing to do on boards given the fact that (a) the quoted poster is no longer here, (b) the post you quoted is obviously from years ago and (c) this type and level of detailing has changed over the years and in order to comply with Part L of the building regs it would be necessary to provide up to date solutions.

Lumen

It's a discussion forum. If you have better advice, post it.