Cavity Wall Insulation

bbam

Hi..
Was wondering if anyone has opted for "Ecobead" pumped insulation in their new-build.
I am drawn to the idea of the pumped insulation for two main reasons;
1. It will provide 100mm of insulation, the complete width of the cavity.
2. Using the pumped insulation will eliminate the risk of poorly installed insulation.

Has anyone done this or have you any advice??

Thanks
bbam

narommy

I may be a bit biased but I think it is the way to go.

150mm would be better

It seals the building and eliminates dodgey fitting of insulation.

Several jobs an aquaintance of mine has done recently already had insulation boards (kingspan type and aeroboard) fitted but they weren't satisfactory

muffler

2 points about this - there is a belief among some people that full cavity insulation can possibly lead to problems with damp and how sure can you be that the entire cavity is insulated?

Doodee

bit of a newbie question but does this reduce noise aswell?

muffler

Doodee wrote:

bit of a newbie question but does this reduce noise aswell?

Indeed it would

Doodee

considering I live in a flat that seems to be made of paper would it help get rid of noises such as generics coming in the apartment block door or the sound of heels on tiled floors?


also whats the cost?

soz for the questions but since the place freezes in winter and has literally no soundproofing i'd be interested to aproach the landlord to consider getting it (especially since its otherwise a swish apartment)

bbam

Interesting points Muffler...
Would I be foolish in believing that since it is approved for use that it has been tested against damp ??. Surely if there was a problem it would be well known/reported??
Regarding the full fill of the cavity... I dont know??, I'd like to hear some experiences from BTDT folks...

Thanks
bbam

De_man

hi

if you look at the diy forum and search insulation/ecobead you'll see
this very issue was discussed at length and generated quite a few interesting
replies.:eek:

Initially, i had intended to use this product, however, after "talking" and
reading other forum members comments i decided to do the research myself

It appears this method of insulation is questionable (driving rain issues in the cavity) read building regulations!!! it's not acceptable in scotland!!
so i decided to stay well clear.

When you read the certs of one particular product it doesn't even meet the building regs!!!

I used a larger cavity then used Aeroboard Platinum in the cavity,
my next intention is to dryline the walls with "Softboard" if i can find it!!


hope this helps

if you can't find the links, pm i might be able to find them here

muffler

Doodee wrote:

considering I live in a flat that seems to be made of paper would it help get rid of noises such as generics coming in the apartment block door or the sound of heels on tiled floors?


also whats the cost?

soz for the questions but since the place freezes in winter and has literally no soundproofing i'd be interested to aproach the landlord to consider getting it (especially since its otherwise a swish apartment)

Doodee, you should post this query in the gardening & DIY forum where I would expect you will get some good advice.

Ewan

De Man,
intending to slab my inner leaf walls with insulated plasterboard....any recommendations..???

Mellor

Ewan wrote:

De Man,
intending to slab my inner leaf walls with insulated plasterboard....any recommendations..???

consider the area between the downstairs ceiling and upstairs floor boards.
there is possibly an uninsulated area of around 200-250mm. This could 5% of the wall. Unless you have a bungalow, then full insulation is possible

Viking House

A builder friend of mine from Finland pumped the cavities in a house about 20 years ago, it was one of his first jobs.
In Finland builders have to give a 10 years guarantee with all their work by law, after 9 years and 10 months he got a call from the client to check out a problem with the work.
The wall wasn't able to breathe with the pumped polysterene in the cavity, moisture built up in the wall and there was substantial mould growing around the window frames where condensation occured within the wall.
While this system gives better insulation and eliminates "Thermal Looping" which reduces the insulation effect by on average 35%, it is not the correct answer.
They have machines on the continent that shread Rockwool and pump it into the cavities or you could use Cellulose, both of which are breathable and a lot denser than Polysterene, holding onto heat a lot longer.
If you are worried about Driving Rain you could re-plaster externally with a better quality external plaster like Stoe or Drywit which is extremely resist to cracking and water penetration while remaining breathable.
If you are plastering externally why not put an extre layer of breathable insulation on the outside.

eoghan.geraghty

De man
you state earlier that a bonded bead cavity fill type insulation does not meet scottish building regs, take a look at this.

http://www.ribaproductselector.com/Docs/AGCerts/AG963228.pdf?ac=

If you can find a more recent report I'd be interested in reading it.
I'm also interested in your search for a softboard supplier, keep us posted please. I was originally to use regular insulated boards until i read viking house's comments about polyeurethene backed boards causing fungus and mould growth.

Viking house, you have previously recommended an external render for improved insulation thats breathable. I agree that would seem to be the best option for a new build but what if someone wants to increase insulation in an existing older house without changing the external look.
From what I've read the shredded rock wool would allow water to transfer from the outer leaf to the inner leaf by capillary action.
Also do you know if the polystyrene used by your friend was of the bead type. I think the small air gaps between the beads would allow the house to breathe, but am interested in any reports to the contrary.

Mellor

fibrous shreaded materials could quite easily allow water to cross cavity. thats one of my doubts about full fill.

Viking House

I agree with Mellor because cement plaster is very water permeable and easily lets moisture through the cavity. Put a concrete block in a tray of water and watch the water creep up the block.

Consider pumping the cavities with shredded rockwool or cellulose and paint the outside of the walls with breathable Old fashioned Linseed Oil Paint. This was the paint they used on the 200 year old sash windows before they changed to petrochemical paint with the VOC's and every second year painting.,
Here is a good link I have no idea of the price, I'm sure its not cheap but it lasts a lot longer and is much more Eco.
http://www.holkham.co.uk/linseedpaints/p_applyemulsion.html
Linseed oil molecules are very small and penetrate a long way into the wall, they bind with 2 oxygen molecules forming a key, stopping water penetration from the outside.
When it was used on windows it allowed the wood to dry out and get hard and at the same time protecting it from the rain.

The Paroc used on the outside of the house as insulation is compressed so much that it acts like Goretex, completly water resistant but very breathable.

De_man

Viking House wrote:

Put a concrete block in a tray of water and watch the water creep up the block.

Perfectly put viking house & mellor,

I even tried this when trying to decide which blocks i'd use in building the house. one of the blocks i tried soaked up nearly a litre of water from the bucket over the space of a few hours!!!!:eek: :eek:

Aeneas

I think the point made by e.geraghty is an interesting one. The tiny pockets of air around the polystyrene beads should allow some measure of breathability within the cavity. In addition the manufacturers say 1) that the beads are impermeable to water and so you don't get capilliary action and 2) that the air pockets allow any water penetrating through the outer leaf to trickle down instead of passing across the cavity. In my own case the beads were additional to existing board insulation in the cavity. I presume these boards would act as a water barrier in the event that mosture did get across the beads.

Ewan

i had originally intended to build a house, but reading this and some other threads, i might just change my mind.....!!! an awfull lot of "donts" and very few "do's"...which is all fine and well.....but.....can ANYONE recommend a insulated plasterboard type slab to line my perimeter inner leaf walls that is breathable and wont cause mould growth......

or is the mould / fungus growth mentioned previously a product of poor building practise more-so than the "breathability" or "lack of breathability" of insulated boards???
Is mould / fungus growth a common experience?

Aeneas

Viking House wrote:

Consider pumping the cavities with shredded rockwool or cellulose and paint the outside of the walls with breathable Old fashioned Linseed Oil Paint. This was the paint they used on the 200 year old sash windows before they changed to petrochemical paint with the VOC's and every second year painting.,


The linseed oil paint may stop dampness entering through the walls. But if you use rockwool or cellulose in this way is there a danger of dampness entering at ground level by capilliary action and thereby crossing the damp proof membrane?

eoghan.geraghty

Ewan, in respons to your post, yes there definitely seems to be a lot more naysaying than good positive advice.
Not a lot of naysaying comes with a link to back it up either.
Not an attack on anybody.
If you are looking at a new build soon you are in the best position as you have an opportunity to do everything right (or wrong:mad: ).

http://www.century.ie/cent/PartialFillCavity.pdf

This was a good link posted by someone else in a related thread (sorry cant remember who to pass on the credit).
He recommends rendered external internal wall insulation.
I THINK this method along with a well insulated timber frame construction would be the best.
Best of luck with the build.

muffler

Thats the joys of a discussion forum - you get a wide variety of views. Whats good and bad is down to personal opinion at times and sure if everyone agreed there would be no debate and hence no need for a forum at all.

Regarding links - there is a massive variety of building products out there with each manufacturer claiming their product is the best. So its probably best at times that no links are given as this can only lead to further confusion.

I think people need to look at this thread in a constructive manner and not be putting it down. Feedback and opinions are given freely and its then up to the OP to make their mind up based on what they have read.

Just bear in mind that this forum is not a building advisory department nor is it a library but it is a source for discussion/debate/advice/opinions relating to matters pertaining to the forum title.

Viking House

eoghan.geraghty wrote:

Viking house, you have previously recommended an external render for improved insulation thats breathable. I agree that would seem to be the best option for a new build but what if someone wants to increase insulation in an existing older house without changing the external look.
From what I've read the shredded rock wool would allow water to transfer from the outer leaf to the inner leaf by capillary action.
Also do you know if the polystyrene used by your friend was of the bead type. I think the small air gaps between the beads would allow the house to breathe, but am interested in any reports to the contrary.

I spoke to the Finnish guy and he pumped the cavities with Polyeurethene foam so that would be a lot less breathable than the Polysterene beads.
I agree with your point on the beads being more breathable.

I was in Holland for Christmas and they are putting Rockwool batts in the cavities with brick on the outside and Poroton or Ytong on the inside.
This Rockwool has water resistant properties as has the shredded version "they say" but I have never used either.
If the external brick was not so permeable then I think it would be no problem filling up the cavity with the Rockwool batts. I still think that Polysterene/Polyeurethene is too light and lacks substance/density to hold onto heat for very long. The Rockwool batts eliminate Thermal Looping because they are pressed tight against the inner wall like a blanket.

Thinking back on what I said I probably would be slower to use Cellulose in the cavity because blocks hold onto damp which would transfer to the cellulose, but then again the cellulose is highly hydroscopic allowing it to naturally transfer moisture to areas where there is less moisture, just like Lime Mortar.
The breathable structure allows the water vapour to be sweated off to the outside. The high pressure inside the house and lower pressure outside facilitate this.

eoghan.geraghty

Muffler, sorry if i appeared to be putting down the thread, defo not my intention.
Just reread my post and i see i was a bit negative myself.
This is an area I have been looking into quite a lot lately and some of the points raised here, in particular Viking House and breathability/mould growth/rise in asthma,are points I never considered myself.
Look forward to more discussions.

Mellor

Viking House wrote:

I probably would be slower to use Cellulose in the cavity because blocks hold onto damp which would transfer to the cellulose, but then again the cellulose is highly hydroscopic allowing it to naturally transfer moisture to areas where there is less moisture, just like Lime Mortar.

Cellulose is hygroscopic. As is lime plaster. But because of the areas there used very different affects are achieved.

Lime plaster as an internal finish helps to control moisture levels in rooms, asorbing moisture at high RHs, and releasint at low RHs. This is a good thing.

Cellulose as a full fill cavity insulator, will absorb moisture from the damp external leaf, and release it to the dry iner leaf. This is a very bad thing. It depends on the conditions that materials are used in.

ardara1

bbam wrote:

Hi..
Was wondering if anyone has opted for "Ecobead" pumped insulation in their new-build.
I am drawn to the idea of the pumped insulation for two main reasons;
1. It will provide 100mm of insulation, the complete width of the cavity.
2. Using the pumped insulation will eliminate the risk of poorly installed insulation.

Has anyone done this or have you any advice??

Thanks
bbam

BBAm - any facing brick on the house or is it all rendered?

bbam

Me again..
The finish will be standard nap plaster..
The range of opinions are interesting and I've been following this as it develops...

Viking House.. I fully appreciate the point about the thermal mass of the insulation material, however will the inner leaf off block & internal block walls not have sufficient "mass" to act as a heat sink? My limited understanding of the thermal equlibrium is that the mass will affect the heat storage and not the transfer of heat which is the primary job of insulation.

I've know folks in this area who have pumped insulation as a retrofit and they speak highly of it... no signs of damp.

I've seen insulation poorly fitted on site... If your not standing over a block layer they'll just shove it in and move on...

I was speaking to the warmfill people and he would give a written guarentee against moisture transfer across a 100mm cavity.

Any more "been there done that" folks out there for feedback ???

Thanks
bbam