How to insulate a mass concrete wall???

agrostar

Hello folks,

Was just wondering if anyone on here has ever insulated a 225mm mass concrete wall? The insulation would be fastened to the external and internal faces of the wall similar to that of Insulated concrete formwork.
I am sure i have seen this done before on commercial projects (highrise flats and offices).
Is it possible to fix the insulation onto the concrete walls?
Could this insulate the walls effectively?
Thanks for your time.......

sydthebeat

agrostar wrote: »

Hello folks,

Was just wondering if anyone on here has ever insulated a 225mm mass concrete wall? The insulation would be fastened to the external and internal faces of the wall similar to that of Insulated concrete formwork.
I am sure i have seen this done before on commercial projects (highrise flats and offices).
Is it possible to fix the insulation onto the concrete walls?
Could this insulate the walls effectively?
Thanks for your time.......

there is no need to insulate externally AND internally, i would stick with external alone.

check out threads on external wall insulation EWI

agrostar

Thanks Syd, the reason im asking is im thinking of casting the external walls of my house using mass concrete and fastening the maximum ammount of insulation afterwards. I was considering using ICF but i reckon it would be much cheaper to cast the walls out of mass concrete and conventional formwork than paying a premuim for ICF. Not sure what i want to do yet if this will even be possible to pass current building regs ect ect. I was reading several of the external wall insulation treads on here but these were only revelant to old houses where the insulation was a retrofit. has anyone ever done this on a new build??

sinnerboy

agrostar wrote: »

has anyone ever done this on a new build??

The first certified Passiv House in Ireland was new build with EWI . It is not just a retro fit option . Don't know why you are putting yourself to the hassle of mass concrete . 215 solid blocks would be my choice .

Mellor

sinnerboy wrote: »

The first certified Passiv House in Ireland was new build with EWI . It is not just a retro fit option . Don't know why you are putting yourself to the hassle of mass concrete . 215 solid blocks would be my choice .

This.

heinbloed

cast the walls out of mass concrete and conventional formwork

Check with the supplier of your formwork (reuseable,professional shuttering elements?) if the external insulation can be fitted seamless (!!) into the shuttering before casting the concrete,
a common method on the EU continent, it saves some installation time.

agrostar

sinnerboy wrote: »

The first certified Passiv House in Ireland was new build with EWI . It is not just a retro fit option . Don't know why you are putting yourself to the hassle of mass concrete . 215 solid blocks would be my choice .

The main reason i was going to use the mass concrete walls is its very fast and i could do all the labour myself, i work with concrete formwork on a regular basis with my line of work and i absolutly hate laying blocks:pac::pac: I reckon for a 2500sqft house ill be able to cast the external walls for less than 3000euro(excluding foundations and insulation). It is only a single storey house with a relatively flat roof which i might clad in zinc or go with installing a greenroof which i would prefer to do.
I will have to do some research on that building you are talking about any chance you would no of any links related to it.
Thanks sinner

sinnerboy

It's featured here

agrostar

heinbloed wrote: »

Check with the supplier of your formwork (reuseable,professional shuttering elements?) if the external insulation can be fitted seamless (!!) into the shuttering before casting the concrete,
a common method on the EU continent, it saves some installation time.

I was thinking about that option alright i never knew they did it on the continent tho. What i was thinking of doing was fitting the insulation inside the formwork then pouring the concrete but i was put off by having to hole the insulation to run the retaining bolts from shutter to shutter which would be very hard to refill and may cause thermal bridging or damp. Also i was worried how the concrete would adhere to the insulation in case it would start pealing off after several yrs
Saying that they probably use a special type of formwork and insulation for this job on the continent. Do you know where i could get some information about this?????

agrostar

sinnerboy wrote: »

It's featured here

Thanks sinner theres alot of reading in there good stuff never knew i might it could ever achieve anything near passive house levels might actually be a vivable option:pac::pac::pac:

heinbloed

Here a picture showing a farmer casting an insulated silo, the EPS included in the shuttering:

http://www.joma.de/index.php?id=156

Here what these shuttering elements look from the distance. Note their stiffness, with proper ground anchoring no retaining bolts are necessary, meaning no interruption of the wall or the insulation, no holes to be filled.

http://www.google.com/imgres?imgurl=http://www.finnforest.at/Image%2520Gallery/ProductGalleries/ConcreteFormworkAndShuttering/concr1/_w/large_concr1_jpg.jpg&imgrefurl=http://www.finnforest.at/anwendungen/bauloesungen/Pages/betonschalung.aspx&usg=__PlyLYfUlMULRIu86PGr8oWAMOOM=&h=365&w=567&sz=49&hl=de&start=25&zoom=1&tbnid=0Gk7Vuyj61jtxM:&tbnh=152&tbnw=236&prev=/images%3Fq%3DBetonverschalung%26um%3D1%26hl%3Dde%26client%3Dfirefox-a%26sa%3DG%26rls%3Dorg.mozilla:de:official%26biw%3D1096%26bih%3D849%26tbs%3Disch:10%2C1254&um=1&itbs=1&iact=hc&vpx=355&vpy=138&dur=11336&hovh=180&hovw=280&tx=114&ty=139&ei=AQLcTOX6Ic294AasssHJCA&oei=-gHcTMueCMWwhQe1v-D_Dw&esq=2&page=2&ndsp=17&ved=1t:429,r:14,s:25&biw=1096&bih=849

When casting think about cable ducts, pipes and sewers and so on, include the wall heating before casting.
By including all these jobs which need to be done at the wall anyhow before actually casting this building method can be very competitive.

Casted concrete is frequently used as part of a heating system, check the www. for " thermally activated concrete " or similar.

Good luck.

beyondpassive

Rc externally insulated, off form interior is stunning and softened with the use of timber. Works great on an architect designed home. Not sure how it would work on a self build though

<SNIP>



Mod edit: Please read the forum charter re posting links to businesses.

agrostar

TBH wouldnt be that interested in using timber cladding, too much maintaince involved and too much of it to be fitted to the building, i would use it within reason (not alot) if I thought it would benefit the building. Which i think it wouldnt........
I realise one slap of a sliotar(if children move in:rolleyes::eek:) and the externally insulated plaster may possibly crack or get damaged. But I would prefer the external walls to be of finished plaster..
Why would it not work in a self-build?
Thanks anyway...................

beyondpassive

EWI is tougher than you think, Its tough enough to withstand a good blow from a screwdriver.

Off form concrete is where you leave it exposed when you remove the forms, so no plaster or paint. Wouldn't work in a mock Georgian.

The concrete can be good as a thermal buffer if its well insulated. This would work well with good solar design and a low temp radiant heating system. where the structure is always about 16-18 degrees With ICF while it gives good U-Values, the concrete dosen't add to the thermal mass in the same way as when all the insulation is placed outside the concrete.