Concrete House

[tdmc]

Ok - architect's own house - 2 years in design - the soul of the idea is in place

300sqm site - two stories, based on a grid (everything in its place), some "see-through" elements. Almost minimal - clean lines. Footprint 8mx 11m
Looking at concrete external walls - but their integrity is lost as we need to line to get the energy rating (R value) up
Want no skirtings, no cornices

Any one have any experience with concrete walls for small scale housing? esp details to maintain the clean look?
have a very rough SU model - but design has moved on a little

Comments very welcome

[GinSoakedBoy]

sorry i am not even sure i understand what you want\need. There's a magazine that was mentioned in another topic that is called Detail, that as name says, it's specialized in details...
Anyway put some images of the model up so that we can see what you are talking about.
And isn´t this in the wrong section?

[takesh h]

Yeah, put the model up. Have designed five of them, might be able to help.
BTW tdmc, I just bought five rolls of Bienfang Yellowtrace (canary yellow) last week. They are fab!

[tdmc]

Ok, an image or two - but they are rough early lerning attempts using SU
A basic two level concrete box. North facade fully glazed (north for sun control in Oz) with multi-fold panels - can open up virtually the whole facade in good weather (spring??)
Ground floor south wall of living area mimics the north - another multi-fold glazed wall
First floor - using full height cavity sliding doors (walls) to allow bed 1, nath and middle room to be a single space - two person household most of the time - so it will be "our" space
East and west walls - concrete
South wall concrete - except as noted above
Site entry - secure at street - house is set back in our own "oasis"

See next image

[tdmc]

3.75 m grid runs north south, 2m grid runs east west
roof more likely to be a pitched "cap" rather than flat as shown
ground level deck - imagine Japanese house theme
theme - imagine barcelona pavillion....(on a budget)

The location is inner city - single storey housing, not great quality - the aim is for this house to be a "bunker" an "oasis" a "retreat" - once past the fence it will be a complete contrast to everything around it. Sylish, minimal, but liveable

struggling with some concepts/positions (as my own client!!)
trying to use conventional materials in a more stylish way - am I wasting my time - should I "just do it"

[SWANK-E]

are you talking insitu concrete walls or precast panels?

[takesh h]

So it is a wooden structure (parti wall, a slab) within a concrete box?
Can you show us an image with concrete structure only?

[tdmc]

Answer 1 was lookng to replicat industrial construction techniques. In-situ or tilt up - problematic, most likely to be pre cast (site is only 300sqm)

Answer 2 - there is no other model as yet. one of the dilemas is the internal structure

inital thoughts (prior to conc walls) was steel column and beam structure
I like conc - durable, no finish, "solid" feel
Our engery rating requirements imply that the walls must be lined - options are timber frame and platerboard (gyproc) or plasterboard on metal channels fixed to inside of concrete face

Ground floor - slab, polished/industrial type finish
First floor - bamboo flooring on timber frame
Roof - trusses, mono pitchhigher at north elevation, back to ceiling level on south

[SWANK-E]

one of the pioneer of tilt up concrete panels is R.M. Schindler with his house on Kings Road, LA

[BruceWalker]

You can actually get transluscent concrete now. That would be cool.

[SWANK-E]

You can actually get transluscent concrete now. That would be cool.

you CAN get it, but most ordinary people can't afford it

[takesh h]

Geelong has less rain fall (about 1/3) than Tokyo, milder summer and warmer winter at 38.08°, about 50m above sea level.
Seems like ideal climate for concrete structure.
If you have engery rating requirements to comply, then you have no chance to have bare concrete walls standing heroically.
Then I suggest to wrap them up outside with insulation, rather than inside.
concrete is such a good thermal mass. If insulated outside and heated properly, you get nice mild environment inside throughout the year.
Besides, you can play around with concrete inside at your will once it's wrapped. All exposed.

[WilsonMetry]

tdmc,
I think you should consider trombe walls (ask primo, he posted something recently about them). I've seen too many concrete houses that have negleted this fantastic environmental control. The mass can be used to store energy or disipate it.

Let all that mass make the building more comfortable!:)

[WilsonMetry]

Thats the idea takesh!

[SWANK-E]

2 more precedents, from similar climate, both from Denton Corker Marshall

Marshall House (http://www.dentoncorkermarshall.com/projects.aspx?p=0&projectID=865&catID=9&f1=type&f2=australasia&pg=1) on Phillip Island, Victoria, Australia
Sheep Farm House (http://www.dentoncorkermarshall.com/projects.aspx?p=0&projectID=901&catID=9&f1=type&f2=australasia&pg=1) at Kyneton, Victoria, Australia

I am sure you know of them

[nicholas]

You can get insulated precast in Victoria...

The other option is that you thicken the walls so that they are exempt from the regulations (+ will still perform well with the added thermal mass)

Though the Takesh method of insulation on the outside would work the best and be less costly

[tdmc]

Thanks for comments for far - much appreciated and inspriational

I lean towards wall thickening - marginal additional cost, and takes car of internal facing 9ie paint or leave raw)
External cladding - environmentally sound, but reduces the 'honesty" of the structure
Am trying to eliminate "complexity", multi layers, fiddly details, e.g. architraves etc to "cover" junctions rather than eliminating the need for such devices
Examples noted by SwankE are along the right sort of lines
Sun modelling with SU and double glazing solve thermal issues pretty well (add insulation - air cell type, or maybe thermal massing - conc.
Thanks

[nicholas]

I think you need to go to 300mm thick (check)

The lack of insulation is only really a problem in colder areas- with your passive solar design, the performance and comfort will be excellent

Make sure the sealer breathes...this will add to the internal climate comfort by absorbing and releasing moisture amerliorating variation

[nicholas]

Am trying to eliminate "complexity", multi layers, fiddly details, e.g. architraves etc to "cover" junctions rather than eliminating the need for such devices

This reduces the complexity of the finished product- clean, pure

Though increases the complexity of detailing and construction...need to be precise and the contractor sympathetic to what you are trying to acheive

[tdmc]

Couple of wall options - seems as though i keep comming back to a fairly traditional way of doing things - plasterboard lining internally, with insulation - to get the R (energy) rating
The second option is marginally more elegant - less impact on resources as well

[tdmc]

The second option

[nicholas]

Reverse the veneer (cladd the outside) for energy efficiency...worth the effort

Thermal mass about 7 times more effective when on the inside

[nicholas]

For precast reference; Kirsten Thompson house Angelsea

"This project is distinguished by the use of a ubiquitous commercial construction method to encase a family holiday house. The use of raw concrete tilt-slab construction produces a building that is robust, and marked by both a financial and architectural economy. The program of the house is a meditation on the ways in which the holiday house allows for different forms of occupation and everyday habits in comparison to more permanent dwellings.




The looser social and familial relations that are particular to the ‘time’ of the holiday house are accommodated efficiently within an extremely taught plan and section. Together, the tilt-slab and the open-ness of the program work together in a paradoxical fashion. When occupied the building can be opened out to the seaside environment through a series of doors which breach the shell. When not occupied the building becomes an uncommonly neat box '

[MICHEL]

Couple of wall options - seems as though i keep comming back to a fairly traditional way of doing things - plasterboard lining internally, with insulation - to get the R (energy) rating
The second option is marginally more elegant - less impact on resources as well

First option wouldn't work here in Belgium, but we have a much wetter climate than you have down in australia... Mainly because of condensation problems (moisture?) behind the plasterboard pannelling. I second the solution of inverting the system, placing the thermal insulation on the outside. If you want to stick to a clean and neat look, maybe rendering over insulation could be an option. Approx 20cm in situ concrete + 12cm thermal insulation + rendering and you have the rolls royce of thermal insulation efficiency. Rendering over insulation is also a good way to avoid any cold bridges. Just an idea...

[tdmc]

Thanks all, a recurring theme - insulate the outside - I'll have a look at that. Therer are some systems here that include a polystyrene insualtion panel (I think sandiwched between two layers of concrete)

Nicholas, I know that house in Anglesea - it appears timber clad from the street, I also know someone who knows the owners and apparently they don't like it very much - they apparently can't cope well with the openness (then why building it in the firstplace!!)

Interesting that simply exposing my "concerns" to "peers" has focussed mae little more on the design, amd extended some possibilities - so thanks to all.

[SWANK-E]

INSULCLAD (http://www.nuplexconstruction.com.au/html/insulclad.htm) is a polystyrene foam exterior cladding on which you render or apply textured paint over... very tough

[nicholas]

INSULCLAD is a polystyrene foam exterior cladding on which you render or apply textured paint over... very tough

Great resource- thanks

Do you know if it works in bushfire areas?

Love their examples ...:bang head

[takesh h]

When I did external insulation with a concrete structure, I used tie-bar of in situ concrete to hold battens, filled gaps with polystyrene foam and clad outside with 12mm plywood, waterproof membrane, galvanized steel sheeting.

[nicholas]

Takesh- do you have photos of the cladding when finished?

[takesh h]

First option wouldn't work here in Belgium, but we have a much wetter climate than you have down in australia... Mainly because of condensation problems (moisture?) behind the plasterboard pannelling.
It wouldn't work in Japan either. You need at least vapor barrier just beneath gypsum boards to avoid condensation inside of walls.
But again, tdmc is in much drier climate than me. :wondering

[InArch]

I just came across this thread and would like to suggest looking at an ICF (insulated concrete forms) wall system. This wall technology works well for both residential and commercial use and is designed to meet higher R-value requirements. Unlike formed concrete walls, an ICF is a panel consisting of 2 layers of expanded polystyrene held together with plastic ties. The ICF's are constructed similar to a concrete block wall. Because the pieces are small and little weight, the wall can quickly be constructed. Additionally, rebar and concrete are added to complete the wall system.

Here in the northeast corner of the US, building codes are demanding better R-values which are no longer achievable using conventional 2x4 wood framing. Also the understanding of wall technology and the components (air barriers, moisture barriers, insulation which made up the complete wall assembly) are now more carefully designed after extensive research has concluded that older methods lead to failure.

-here are some useful links:

www.forms.org
www.quadlock.com
www.polysteel.com
www.rewardwalls.com

[tdmc]

Has anyone experience with plastic panels for cladding
There is a product

www.plaspanel.com.au

Various thicknesses and sheets 1.2 x 2.4, able to be cut drilled etc. welded and edged, but subject to a fair bit of movement

Made from recycled plastic - hence weather resistent etc. and relative inexpensive, but not used in the way I'm looking at - external cladding over concrete panels (battened out somehow, with the cavity insulated)

Any ideas/experience?:cheers:

[taxodaxo]

I have used quadlock extensively. On a recent Community hall project we were able to exceed R44 on the walls. The hall was next to an ice arena, and we are looking at recycling the waste heat from the arenas ice plant to heat the building, hence wanting high r values.
An experienced contractor in quadlock can erect an pour an average size residence (2500sq ft ) in about 4-5 days, which puts the walls readyfor drywall on the interior no additional vapour barrier required) and cladding exterior.
A very adaptable system

[InArch]

we were able to exceed R44

Can you share your wall section detail with the forum. Typically with ICFs the manufactures claim high R-values, but once a wall is calculated for R value, the numbers are far less. Concrete in itself provides an R-value of 0.08 per inch which is not much.

here is a good table to base an R-value calculation:

http://www.coloradoenergy.org/procorner/stuff/r-values.htm

[taxodaxo]

InArch
Here is some of the data from Quadlock. It appears they have backed off slightly from the R-44 claim to R-40, and even with calculating in materials and air barrier etc total would be R-42.75 still not shabby. It was achieved using Quadlock Plus Panels on both wall faces and a 10" concrete pour. I will attach their data sheet.

[taxodaxo]

We have also used Arxx block as well, but the reason I keep returning to Quadlock is that most other panels ship with their nylon ties cast into the styrofoam panel, forming the space for the concrete. This means you are shipping a lot of air, and shipping is costly. Quadlock ships as individual panels, with the ties seperate. Also most other systems have premade corner blocks, 45 degree angle blocks etc, with quadlock you cut and assemble on site. In one of our Arxx projects several of the corner blocks were damaged in shipment, which meant a few day delay until they could be replaced.
Otherwise the Arxx performed as well as the Quadlock.
Attached is a panel photo from the quadlock propoganda file.

[taxodaxo]

Also a link to technical data should anyone be interested in flamespread ratings etc

www.quadlockneusa.com/pdf/678app.pdf

p.s. I am new at forum use, and have tried to apply the above as a url link, if it fails it may require moderator intervention, I'll get it yet.

[taxodaxo]

The problem with ICF's in relation to this thread is, since you don't strip the styrofoam forms you don't get the look or feel that I beleive was intended as you have to apply finishes.
Attached is a rammed earth wall, perhaps you could consider this?

[taxodaxo]

Couple of wall options - seems as though i keep comming back to a fairly traditional way of doing things - plasterboard lining internally, with insulation - to get the R (energy) rating
The second option is marginally more elegant - less impact on resources as well

The image posted in this quote shows a concrete exterior wall with frame wall inside, gypsum board attached. There is an inherent problem with this system as the vapour barrier should be placed on the warm side of the wall, which traps the wood members between the concrete, which is porous and can introduce water, and the vapour barrier. This is a recipe for mould, however it has been standard practice by contractors doing basement finishing work (for instance)
I don't know what R-value you have to bring your walls to but I would seriously consider styrofoam. There are systems developed whih allow for strapping, I believe one is called Clad Mate by Owens Corning, although it has been a while since we have spec'd that so things may have changed.

[tdmc]

oh taxodaxo, my mistake, the intent is for the concrete to be exposed internally ( I recall that this method was developed in another thread about the same time that I started this one), so the question I'm struggling with is how to clad externally.
And I want to avoid needing an applied finish such as render. The whole building is intended to be "true" to its materials rather than covering up.
Metal cladding - such as aluminium is very expensive ($300 per sqm)
The plaastic panels I've mentioned are interesting, but apparently expand quite a bit, so I'm not sure if they are suitable for large areas/building
I'll keep searching

[lightson]

Can you share your wall section detail with the forum. Typically with ICFs the manufactures claim high R-values, but once a wall is calculated for R value, the numbers are far less. Concrete in itself provides an R-value of 0.08 per inch which is not much.

here is a good table to base an R-value calculation:

http://www.coloradoenergy.org/procor...f/r-values.htm

Hi guys

Thanks for that information and the site, Hi I am charlene , designer arch. from belgium.., and looking forward to exchange thoughts and knowledge with ya all...

Thanks

Charlene

[pitrak]

oh taxodaxo, my mistake, the intent is for the concrete to be exposed internally ( I recall that this method was developed in another thread about the same time that I started this one), so the question I'm struggling with is how to clad externally.
And I want to avoid needing an applied finish such as render. The whole building is intended to be "true" to its materials rather than covering up.
Metal cladding - such as aluminium is very expensive ($300 per sqm)
The plaastic panels I've mentioned are interesting, but apparently expand quite a bit, so I'm not sure if they are suitable for large areas/building
I'll keep searching

Have you consider wood?

[tdmc]

pitrak, considered and discounted wood very quickly - doesn't suit the style/look of the house, and requires maintenance, but a good thought, thanks.

Still looking....

[Jimmern]

There are not that many materials to choose from if you want 'true' finish to the exterior. Untreated wood that weathers naturally such as cedar, redwood, or siberian larch come to mind.

Insulate the concrete, find a suitable expression for the wood on the outside. Then you can use wooden details on the inside in some places to bring the wood in and add warmth to the concrete.

I'm personally not so keen on 'plastic' or styrofoam as a finished surface with some of the systems above, although the high R values sound good.

[gaffaman]

I don't know if you've considered using a tilt-up system but it sounds like something you might consider. There are systems that allow insulation to be sandwiched between concrete on both sides. This would let you have the exposed concrete look inside and out, as well as the additional insulation. The concrete could have just about any type of finish you would want.

Here's a link to a product that is available here. I'm sure there would be something similar available in Oz.

http://www.thermomass.com/

[tdmc]

gaffaman - it's in the back of my mind - the site is small - around 300 sqm, so panels will be fabricated off site and craned in on delivery
If I can "apply" a cladding to the walls and keep the thickness to a minimum it would be preferrable. 150mm walls fo the two storey sections - this means the sandwich wall would get up to 350/375mm
Concrete panels seem to be around $110/sqm - I guess doubling this for sandwiched panels, which isn't too bad from a cost perspective,
I'm getting a price on glazing the external face of (most) walls - which could mean a kind on Trombe wall possibility, I'll keep the forum posted!

[tdmc]

update

Thanks gaffaman - sandwich panels looking very promising - the local rep is knowledgable and very easy to get along with. Cost seems to be less than concrete panel with "sexy" externals cladding (eg glass, or aluminium). There's a supplier - get this - around 500km away (300 miles) who is cost effective - cheaper than some locals - on budget figures anyway.

external cladding which doesn't require treatment and looks minimalist etc is very pricey - so am heading towards the sandwich

"Sandwich House" a good place for parties and dinners I think!