SIPS v ICF - is Phase shift really a factor?

[saveasteading]

1 hour ago, sgt_woulds said:

 there is no spare capacity to add PV panels,

I had missed this, now obvious,  option!

 

Sedum is very heavy so out of the question.

But PV? 

It's likely this could work. If you were to ask an SE to look into it they might find a bit of spare capacity.  Specifying joists is simply choosing the next size up that takes the load, so there is usually some spare.

Then they might consider the gantry spanning between structural walls, not all bearing on the roof.

OR  joists will have little capacity at midspan but more near to  the supports... fix there.

If the task is to make this specific thing work, then they can look at several options, review other loadings more critically, and even take an overview if it is not quite there.

First find a lightweight PV system.

 

 

 

[sgt_woulds]

I'm an ex PV specifier / installer and roofer, so I'm aware of my options... none of which will provide significant shade for my roof unfortunately. 😞 

 

But enough distraction from the OP - hopefully we convinced not to use SIPs, but I wouldn't go for CIF either!

 

I've felt guilty enough about the amount of global warming my house will have contributed to with SIPs, there is no way we should be building monolithic concrete structures in this day and age. 

 

What are the percieved advantages of CIF that would push Mueller to use this method?

 

 

[Muellar]

1 hour ago, sgt_woulds said:

I'm an ex PV specifier / installer and roofer, so I'm aware of my options... none of which will provide significant shade for my roof unfortunately. 😞 

 

But enough distraction from the OP - hopefully we convinced not to use SIPs, but I wouldn't go for CIF either!

 

I've felt guilty enough about the amount of global warming my house will have contributed to with SIPs, there is no way we should be building monolithic concrete structures in this day and age. 

 

What are the percieved advantages of CIF that would push Mueller to use this method?

 

 

Perceived advantages 😉 are in part due to me liking solid things and the feel you get from that, too many bad experiences of new build TF and studwork/squeaky floors, then our site is exposed as that way we get the views we'll have out over Lough Neagh, so I know we'll get hammered by the wind as I grew up in that area. To keep within planning ridge height without having a sprawling footprint we also made use of the fall of the land so have a partial basement - making one part 2 floors with only 1 appear above external ground level.

 

I'm also a 'believer' in thermal buffering/mass as well so the whole thing stacked up to me for using ICF and I liked the idea of a thinner EPS layer inside than outside. I've always felt that cavity/brick-block has had it's day so that wasn't on my list of desired building forms.

 

We will clad the whole thing partially in metal including the roof, standing seam either zinc or greencoat plx and the rest in charred timber, so in part what's behind those doesn't really matter.

 

And yes... this whole discussion and the points you are all providing are swaying me back to ICF - although I get that you @sgt_woulds would see another method as being better than ICF. I'm guessing due to the carbon load of concrete from your comments?

[saveasteading]

2 hours ago, sgt_woulds said:

I'm an ex PV specifier / installer and roofer, so I'm aware of my options... none of which will provide significant shade for my roof unfortunately. 😞 

 

But enough distraction

 No please: more distraction.

This has got my attention and your experience is wanted. 

Self evidently, a PV panel will prevent some ( a lot of) solar energy from reaching the roof. Not only is it shade but also the energy is being taken away as electricity.

Can you explain why it would be insufficient, in your circumstances of on principle?

[saveasteading]

33 minutes ago, Muellar said:

guessing due to the carbon load of concrete from your comments?

I can see the attraction of icf and I costed out a couple of buildings this way, at design concept/tender stage. It wasn't right for my business and these were both private houses,  but I can see the attraction for a self build dwelling.

 

My biggest concern is buukding end of life*. I have a horrible image of the building being scrunched by a concrete crusher and eps being mixed with the rubble or flying off in the wind. Then the crushed concrete being laid as hardcore full of eps.

 

One could redo any "carbon load" with this shown as waste or contamination, to get a different solution.

 

Or perhaps and I hope,  this has been thought through and resolved already.

 

* this can be much sooner than the design life due to land use changes.

[sgt_woulds]

16 hours ago, saveasteading said:

 No please: more distraction.

This has got my attention and your experience is wanted. 

Self evidently, a PV panel will prevent some ( a lot of) solar energy from reaching the roof. Not only is it shade but also the energy is being taken away as electricity.

Can you explain why it would be insufficient, in your circumstances of on principle?

 

 

Perhaps, but we should hive it off to a seperate conversation 🙂

 

 

16 hours ago, Muellar said:

Perceived advantages 😉 are in part due to me liking solid things and the feel you get from that, too many bad experiences of new build TF and studwork/squeaky floors, then our site is exposed as that way we get the views we'll have out over Lough Neagh, so I know we'll get hammered by the wind as I grew up in that area. To keep within planning ridge height without having a sprawling footprint we also made use of the fall of the land so have a partial basement - making one part 2 floors with only 1 appear above external ground level.

 

I'm also a 'believer' in thermal buffering/mass as well so the whole thing stacked up to me for using ICF and I liked the idea of a thinner EPS layer inside than outside. I've always felt that cavity/brick-block has had it's day so that wasn't on my list of desired building forms.

 

We will clad the whole thing partially in metal including the roof, standing seam either zinc or greencoat plx and the rest in charred timber, so in part what's behind those doesn't really matter.

 

And yes... this whole discussion and the points you are all providing are swaying me back to ICF - although I get that you @sgt_woulds would see another method as being better than ICF. I'm guessing due to the carbon load of concrete from your comments?

 

 

I like @solid' too, but other construction methods can achieve that.  I was lucky enough to experience many types of construction back when I started installing PV.  Back then the average price for a 1kw system was £20k!  Only the absolute eco warriers were willing to pay, and they were as varied a bunch of characters as the houses they built.  Great days...

 

I've experienced TF, Strawbale, Rammed Earth, Cob, Earth Bag, Earth Sheltered (Stone built), Underground Bunker, ICF, Mass Timber, Double skin Insulated Wattle & Daube, Container house.  

 

The best timberframes can match any 'solid' construction method with correct detailing and pumped cellolose or woodfibre insulation, but, like anything, it will depend upon the quality of the build.

 

As far as concrete goes:

 

One of our customers and his architect built two houses side by side using different methods; Dense (fly ash) concrete block solid wall with external insulation, & ICF.  Both had the same notional U-values and apart from the walls, all finishing details were identical.  Multiple sensors everywhere.  I spoke to the architect a couple of years later and he reported that the blockwork house was performing slightly better.  His suggestion was that the internal layer of insulation on the ICF was blocking some of the advantages of thermal storage but the difference was marginal.

 

The concrete block wall was quicker and easier to build (ICF collapsed twice during pours, even with manufacturer supervision on the site) and had about half of the upfront carbon than the ICF. 

 

They had the advantage of a highly motivated and dedicated team of builders - probably the best I've ever known.  Would a blockwork wall built by the typical Great British Builder have perfored as well as the ICF?

 

Of course cost is a factor.  If I'd had the money, I would have like to have built a TF with Woodfibre insulation throughout.  SIPs with a thin layer of WF was (supposed to be!) a cheaper compromise for a higher performing build, balanced against up front emmissions.  If I was doing it again with the same budget, I would probably build a hybrid cavity wall with STROCKS.

 

 

 

Edited 12 hours ago by sgt_woulds

[saveasteading]

7 minutes ago, sgt_woulds said:

STROCKS

I'd never heard of this term, so thanks.

Otherwise known as adobe?

 

[sgt_woulds]

Yes but a standardised form and tested for structural use - I believe they have BBA, so easier get BC than some other soil based solutions. 

 

Used for inner leaf of cavity walls.  Presumably can also be used in a solid wall with external breathable insulation.

 

We had an architect/builder who was interested in using our woodfibre EWI on an earth block wall using BETTABLOK last year.  I really must ask how they got on...

[saveasteading]

1 hour ago, sgt_woulds said:

I've experienced TF, Strawbale, Rammed Earth, Cob, Earth Bag, Earth Sheltered (Stone built), Underground Bunker, ICF, Mass Timber, Double skin Insulated Wattle & Daube, Container house.  

Again, for a new post perhaps. I'd love to know more. You appear to have been involved in lots of these experimental processes. I vaguely recall there was such a trend, perhaps 20 years ago.

[JohnMo]

2 hours ago, sgt_woulds said:

Would a blockwork wall built by the typical Great British Builder have perfored as well as the ICF?

You have to idiot proof builds, and do what's done locally to great extent or be prepared to do it yourself. Would be my view. Around us it's timber frame kit and brickwork, which I didn't want, so went wood crete ICF and did myself. No walls collapsed or any blow outs encountered.

[Muellar]

5 hours ago, JohnMo said:

You have to idiot proof builds, and do what's done locally to great extent or be prepared to do it yourself. Would be my view. Around us it's timber frame kit and brickwork, which I didn't want, so went wood crete ICF and did myself. No walls collapsed or any blow outs encountered.

Thanks @JohnMo I'd seen you've used Ecobrix and that to me was more 'idiot proof' than a lot of other ICF products. The blocks are substantive so would hold their own. I guess i'm at that wavering point and saw a SIPS product that attracted me and would shave 3 months off the programme and now we'll be renting that grabbed me, plus it's a lot thinner even adding in 50mm of cork etc, so I quite liked that as well. 

 

Given a number of life changes and i'm from a construction background I'm going to PM the build and have a few good folks I know that are keen to work with me on an ICF build, wheras the SIPS would be a package giving me a shell/roof and intermal walls quickly... but I think i'd be trading off on factors that will make it a home.

 

Lots of great feedback here that has me thinking a lot.

[JohnMo]

This took 4 weeks, two of us never done it before (working 8 hrs days in Dec in NE Scotland), 70m perimeter, up to 3.5m high at front.

Then there was a break over Christmas and new year and roof materials arrived 12th Jan

 

First week of Feb roof on. If you exclude the Christmas break, 9 weeks, not sure where the savings of 3 months come from.

 

[-rick-]

13 minutes ago, JohnMo said:

This took 4 weeks, two of us never done it before (working 8 hrs days in Dec in NE Scotland), 70m perimeter, up to 3.5m high at front.

 

First week of Feb roof on. If you exclude the Christmas break, 9 weeks, not sure where the savings of 3 months come from.

 

Impressive!

[Nick Laslett]

ICF can be quick. Our Thermohouse crew of three guys assembled the ground floor walls in 4 days, then spent 4 days bracing and erecting the scaffold platform, then poured the walls on the Friday of the second week. 
 

So 10 working days from blank foundation to poured concrete ground floor walls. 

Edited 1 hour ago by Nick Laslett