Renovation Projects - Insulation Suggestions.

[Superman]

Hey,

I'm an architect, usually post on AAM.

Two questions

1. Renovation of a brick faced solid masonry wall building - i.e. internal only. Any alternatives to shelterboard that you'd recommend? E.g. softboard. How does it compare to alternatives?

2. Renovation of a highly exposed house by a bay. The existing plaster finish has perished and has to be replaced. Also the house has to be insulated. The current proposal is for plaster externally and drylining - playing it safe.
Anyone got any idea how effective types of outsulation are and what the lifespan of them is?

Thanks.

[heinbloed]

Hi!
For your first project I would recommend a specialist company, no particular one but one that can show results with a proofen quality. Internal insulation on cold walls is troublesome, a real tight moisture membrane/barrier is a must to avoid mould growth/sick building syndrome.
For your second project as well as the first check this official link, it shows us formulas to calculate the cost/benefit side of the project (usually the external insulation is the best answer/investment): http://www.ecofys.de/de/veroeffentlichungen/documents/EurimaIII_final.pdf
The final prices given in the report are samples only, so use the formulas to calculate your own results.
Good luck!

[VikingHouse]

1. Renovation of a brick faced solid masonry wall building - i.e. internal only. Any alternatives to shelterboard that you'd recommend? E.g. softboard. How does it compare to alternatives?

2. Renovation of a highly exposed house by a bay. The existing plaster finish has perished and has to be replaced. Also the house has to be insulated. The current proposal is for plaster externally and drylining - playing it safe.
Anyone got any idea how effective types of outsulation are and what the lifespan of them is?

Softboard lets the wall sweat and you don't have the problems that arise when you dryline with Kingspan when the floor joists penetrate the airtight/insulation layer.

Weber are offering a 60 year guarantee with their external insulation system in Ireland.

[bestwall]

Hey,

I'm an architect, usually post on AAM.

Two questions

1. Renovation of a brick faced solid masonry wall building - i.e. internal only. Any alternatives to shelterboard that you'd recommend? E.g. softboard. How does it compare to alternatives?

2. Renovation of a highly exposed house by a bay. The existing plaster finish has perished and has to be replaced. Also the house has to be insulated. The current proposal is for plaster externally and drylining - playing it safe.
Anyone got any idea how effective types of outsulation are and what the lifespan of them is?

Thanks.

hi we completed a project on a house for a client in east cork that is located close to a cliff edge on the coast.we used weber/kingspan external insulation system with a an acrylic render,as we felt under the circumstances this would stand upto the elements much better.personally i feel you are always better to insulate externally thus allowing the concrete blocks on the internal to store and manage your internal heat much better than if the structure was drylined.by externally insulating your helping to eliminate cold bridging,something that drylining cannot do.
hope this helps

[Superman]

hope this helps

Yes it does - thanks all.

[Scaffolder]

Best wall if the block is insulated from the ground you woul be correct, if it is not you have a very lagre thermal bridge at the base of the wall to the ground.

Drylining will break the bridge at the base. Either that or lift the house up and sit it on some insulation:)

Another problem area with external insulation is at the top of the wall plate, you will also have to insulate the eaves soffit and push the ceiling insulation in as far as possible towards the fascia.

[bestwall]

Best wall if the block is insulated from the ground you woul be correct, if it is not you have a very lagre thermal bridge at the base of the wall to the ground.

Drylining will break the bridge at the base. Either that or lift the house up and sit it on some insulation:)

Another problem area with external insulation is at the top of the wall plate, you will also have to insulate the eaves soffit and push the ceiling insulation in as far as possible towards the fascia.

the wall is insulated from top to bottom.as for drylining you are insulating from the inside thus not allowing your external walls to store any of the heat you will have built up.you need to stop the cold from entering your structure at the earliest opportunity.by drylining you are trying to stop it at the last.
as for insulating around the edge of your ceiling you will still have this 'problem' if you dryline. there is now spray on insulating foam to overcome this problem.

[VikingHouse]

hi we completed a project on a house for a client in east cork that is located close to a cliff edge on the coast.we used weber/kingspan external insulation system with a an acrylic render,as we felt under the circumstances this would stand upto the elements much better.personally i feel you are always better to insulate externally thus allowing the concrete blocks on the internal to store and manage your internal heat much better than if the structure was drylined.by externally insulating your helping to eliminate cold bridging,something that drylining cannot do.

Putting Polyeurethene insulation on the outside of a wall stops it from breathing, creating moisture to build up in the wall as it is prevented from drying out. A damp wall looses 20 times more heat than a dry wall reducing the effect of the external insulation by 20%. There is lots of German and Scandinavian research to back this up.
When Polyeurethene leaves the production line its Lambda value is 0.015, when it goes on the market four weeks later the Lambda value has fallen to 0.025 which is what it is marketed at. What is the Lambda value after two months, a year or after it gets wet under the floor?

The best external insulation product for older buildings is water resistant breathable Rockwool. This dense Rockwool is about 10 times heavier than Polysterene or Polyeurethene and keeps your house cosy 10 times longer.
Lightweight insulations are only suitable for under the foundations where the external temperature fluctuations are much less and there is no wind chill factor.

[heinbloed]

Another thing to look at is the longevity of the external insulation material: PU boards are usually covered in aluminia foil, but not in pure aluminia foil. The Kingspan PU material boards I have seen are containing brown paper, between the (very thin) aluminia foil and the PU-foam itself. All natural organic substances and fibres will sooner or later rot when exposed to moisture. If this paper rots then the plaster incl. the PU foam will come down....But there might be newer, better suited boards available for the external insulation job, better ask for a longterm guarantee.
The problem of gassing out of the pentane(the foaming agent for the PU boards) has not only been noticed by Viking House. The manufacturers are stating that the Aluminia foil is supposed to hold the gas within the cured foam. I have my own experience: When buying a fresh piece of Kingspan board (the aluminia backed type!) and breaking/cutting it up the surface of the freshly broken pieces can easily be lighted with a cigarette lighter straight after cutting it.Propane/Butane/ Pentane -the gases used to foam up polyurethane-are a fire risk, combustable. The surface of the fresh cut burns -but only if the board is new! A piece from the same board that is a few month old won't show the same effect..... What happened to the gas though ?! It has dissolved, vanished, dissapeared. And with it a good deal of the board's insulating properties has vanished as well.
Try it out yourself.
My sense of smelling tells me the same: the fresh boards smell of gas when cut but the the older boards hardly smell of anything like the new ones when freshly cut.
How did Kingspan get away with that when applying for an Irish Agreement Certificate- with the help of the PDs?!

[VikingHouse]

A lot of builders pour concrete straight on top of these Alu foil Polyeurethene insulation boards. The cement quickly dissolves the foil that holds in the insulating gases which escape a lot quicker reducing the U-value. The water in the concrete makes the insulation wet also reducing the U-value. This material is used a lot under concrete floors but is not suitable in my opinion.

[Adrian Hennessy]

so for 'under floor slab' insulation do you recommend the use of 150mm of extruded polystyrene???

[VikingHouse]

Hi Adrian

We are presently building houses on top of 30cms of Polysterene with the walls sitting on Structural Polysterene that can take 10 tonnes per m2.
This Supergrund system gives a U-value of 0.10 for the floor and reduces the U-value of the wall by 0.11 by cutting out the cold bridge between the walls and the floor.

[heinbloed]

30cm EPS under the slab, that's about the best insulation ever used in Ireland.
Will you get the structure certified to the German PHPP? You would be the market leader here, propably in the entire English speaking part of Europe.
Good luck !

[Adrian Hennessy]

how does polystyrene act when in contact with water???

as you place your first layer below the DPM membrane it will inevitably get wet, does this not reduce its insulating properties???

do you have any kind of self certification?? as a certifier i would be hesitant (but certainly not unwilling!!) to sign off 'untested' (?) forms of construction... how do you get around this??

is there a structural guarantee with that foundation method??

[heinbloed]

Expanded PolyStyrol (EPS) is a certified product for use under many conditions of the construction industry-since about 50 years. Made in Germany.....by BASF originally. It's even used under motor highways.
It get's wet on the outside when dipped into water and when wrangled under water the capillars (between the expanded pearls)will get filled with water as well. As harder(denser) the grade of the EPS(yes, there are different grades of it) the less the capillarity, the less water gets into it.The EPS used under loadbearing structures is of the denser,harder grade. Note: the capillars are the least k-Value influencing part of the EPS board, it's the air filled expanded parts,the pearls, that benefit the k-Value decisive.
And then there is Extruded Polystyrene(xPS) which shows some different characteristics. First of all XPS has no capillars and is therefore not "breathable" whatsoever- in oposition to it's cheaper older sister EPS. And it is better insulating as well.
If space is not an absolute restricting factor then EPS is due it's price the more economical and ecological solution compared to XPS.XPS comes in different grades as well. A typical sample of usage for XPS is as a buffer - on a roof rack for example-to avoid demage to the surfboard or the bicycle or the roofbox. It's surface is slippery compared to the rougher,blunter surface of cut EPS.
Polystyrene-expanded, extruded, worked into a foil or casted into a mould- has the major weakness of not being resistant to UV light(ultraviolet radiation), towards sunlight. And that's about the only thing that can break it down in nature calculated in mankind's timing. Fire of course is the other point.
Both degrading influences can be counterfeight by addition of various compounds, but these compounds are neither "green" nor healthy nor cheap. And in it's most used cases-insulation and packaging- not necessary.
More modern insulating EPS sheets can be got with added graphite. This graphite is a natural mineral and it doesn't rot either. It gives the boards a blackish- greyish colour(graphite!) and brings the k-Value up to that of gas filled PU boards.And makes them a bit more resistant to UV demage as well. Without loosing the gas after a while(smiley).
For further information try also "aeroboard", "basf" or "wikipedia" in the www..

For under the slab - in the construction industry- foam insulation material can be placed either under the radon/vapour barrier or above it. Since it is the ENCLOSED air that makes it insulating. For the protection of the vapour/radon barrier the barrier is better placed on top of the foam. However,carefully build by whacking down the gravel and covering it well with fine graded sand (and that compacted and level as well!) it can be done the other way as well. But the less pressure is aplied to the barrier by the (ground) water and the radon gas the longer it will go.So it makes absolutly sense to put the barrier on top of the insulation.The radon can for example seep sideways out of the EPS(thanks to it's cappilarity!) before it's concentration becomes unbearable for the barrier. When speaking about extreme concentrations of radon in the ground combined with a failing sump there is still an emergency exit by using EPS(smiley).

[VikingHouse]

30cm EPS under the slab, that's about the best insulation ever used in Ireland.

Hi Heinbloed

ScanHomes have been using 30cm of Polysterene under their houses for some time in Ireland now with the L-element system but the insulation reduces to 10cm at the perimiter as the slab thickens to take the weight of the walls. The Supergrund system has a thermal break between the slab and the ring beam improving the U-value by 0.08.


Will you get the structure certified to the German PHPP? How would we do that?


You would be the market leader here, propably in the entire English speaking part of Europe.
There is nothing to beat Supergrund anywhere in the World Heinbloed (smiley).

[heinbloed]

To VikingHouse:
I never stop learning, hopefully. The "thermal break" of Supergrund is new to me, I hope it works out fine on your site.
The "Passive House Planning Package" allows a civil engineer to check the work done on site and comparing it with the data of the PHPP. And then the confirmity of the works with the PHPP is signed by the civil engineer.
The civil engineer wouldn't have to be employed by the builder on a full term basis, just the for the individual job. But when signing his statement the engineer is fully responsible for the confirmity, with his private property/wealth. So if signing a doubtfull site and been proven wrong (in a courtcase for example) could mean that this was his/her last job in the trade.
It might be financially worth it to go for the official seal with the PHPP, it's energy demand rating outbeats the traditional "Homebond"certificate by lenghts.The new 2007 English version is now available, as far as I remember for around €150.-.
If the civil engineer needs training on how to use the the PHPP then this can be got as well from the Passiv Haus Institute.During a one or two day workshop the candidate will be fit. Courses are offered in various countrys, it might suit an extended holiday trip. Vorarlberg in Austria for example has a very good kitchen,excellent lodging and some fine surroundings....( http://www.energieinstitut.at/ ). The home of the poroton block (Wienerberger) is only a short journey away, for their prospective clients free tours can be arranged (smiley) , Wienerberger bought (together with Solvay) only a few weeks ago the Irish company Qualpex in Cork, so they're surely interested in the Irish market...