Building methods for passiv standard?

BarneyMc · 21-01-2012 08:19PM

beyondpassive wrote: »

http://www.integrated.ie/wp-content/uploads/2011/08/EPS-rafts.jpg

Looks like figures 13 and 14 are 250mm cavity walls built on a raft foundation. What's the main difference between the two? Looks like the top floor screen in fig. 13 is more insulated from the inner leaf than that in fig. 14. Thanks.

kboc · 21-01-2012 09:35PM

beyondpassive wrote: »

I don't understand the question?, you can use wide cavity on a thermally broken rising wall or alternativly on an EPS raft (supergrund, viking, isoquick etc.) The raft has zero thermal bridging.(in fact positive psi for Passivhaus), but can be slightly more expensive than strip, but much quicker. I don't see it as fair to compare on mere material costs.

http://www.integrated.ie/wp-content/uploads/2011/08/EPS-rafts.jpg

sorry yes i was not clear. I meant a cost between the common strip found incorporating quinlite blocks in comparison to insulated raft.

The fact that it is "only" slightly more expensive, and the other advantages of insulated raft like speed of build, is insulated raft a no brainer really?

(in fact positive psi for Passivhaus)

what is this?

I also seen this on your web site
http://www.integrated.ie/wp-content/uploads/2011/08/Clonard-Passiv-timber-frame-3.jpg

Is the 400mm on the raft and 310mm timber frame insul overkill or is it justified?
impressive looking work

K

beyondpassive · 21-01-2012 10:45PM

BarneyMc wrote: »

Looks like figures 13 and 14 are 250mm cavity walls built on a raft foundation. What's the main difference between the two? Looks like the top floor screen in fig. 13 is more insulated from the inner leaf than that in fig. 14. Thanks.

EPS formwork rafts are all about ground conditions and loadings, these are two different solutions for two different types of site, this subject gets well into the structural engineers area of expertise so I couldn't comment further.

kboc wrote: »

The fact that it is "only" slightly more expensive, and the other advantages of insulated raft like speed of build, is insulated raft a no brainer really?

You might think so, if only build decisions were rational. There's usually so many emotive reactions, opinions, prejudices and risk aversion decisions made that the obvious solution is the worst one.

kboc wrote: »

"positive psi for Passivhaus" what is this?

The junction is better insulated than the average of the flanking elements (flanking elements being wall+floor or roof and wall or window and wall)

kboc wrote: »

Is the 400mm on the raft and 310mm timber frame insul overkill or is it justified?

For this particular project with its unique shape, using PHPP analysis it showed that this spec could be justified by minimising heat demand to a level where the extra up front investment was recoverable in the short to medium term and the benifits to occupant comfort and heating system effectivness required it.

some recent site photo's on two types of Passive house build method:
http://s1241.photobucket.com/albums/gg516/Beyondpassive/Site%20Photos%20January/

sas · 22-01-2012 09:06PM

keru wrote: »

I follow your thinking and it is very reasonable, however, how can you be sure it will only cost you €400 to heat your house in say ten or twenty years time? The way the price of oil, electricity and gas has gone up in recent years doesn't bode well for the future. Unless you can produce your own energy instead of purchasing it surely it makes more sense to lower your need for it?
In conclusion, I believe, but correct me if I am wrong, that your figures do not give enough weight to the rising price of energy. How much weight to give it is the real question and probably need a crystal ball to answer that one!

I'm not sure where you are getting the €400 from.

Ok, so you are taking the position that oil will rise in price and that any difference between the heating costs will hence be larger in the future.

If you borrowed the additional money for the better structure, you are also at the mercy of increasing interest rates.

What's to say that there isn't a breakthrough product that will replace oil based systems as our future energy provider. This is looking less likely but it could happen.

My point is that I have spent the additional money to build a passive house. I saved wherever it was possible. I now look at my spend and can see no realistic chance of break even during the lifetime of the mortgage. At which stage the house will require some maintenance (windows replacing for example) which will push any breakeven point out in further into the future.

I've made my point for this thread. Very best of luck with your decisions.

Eoghan Barra · 22-01-2012 10:24PM

Sas, I'm very surprised and sorry you seem to be regretting having spent the extra on building in extra insulation and a high level of airtightness etc to get to passive standard.

Surely as well as future savings on heating bills this is to some extent also compensated by the few bob you must have saved by not having to build in a central heating system? And surely it's not only a question of economics, but one of comfort, health and general well-being? And is the question of carbon footprint and each individual's impact on the global environment not also relevant here?

I imagine you're very aware of all these aspects or you wouldn't have chosen to go down that road in the first place. To me installing high levels of insulation, mhrv, limiting thermal bridging etc while you're in the process of building is a no-brainer on lots of levels. I think the ones who'll have the biggest regrets are those who are building to what are now standard levels, as houses built in this way will be considered in only a few years time in a similar way to how we now look at old damp, cold, dark stone cabins built a 100 years ago.

Nor are their economic difficulties likely to be much less than yours, but at least you'll have the satisfaction of living in a really decent house.

fclauson · 22-01-2012 11:17PM

There is a lot of nonsense spoken about Passive build

a) Passive builds do not need normal heating system - nonsense - a passive build needs continuous heat during the cold weather to maintain a constant internal temperature - e.g. mine will need a continuous 3.5Kwh (more if its dark, damp murky and miserable) - every hour of every day its cold - that’s how passive houses work

b) Passive houses are just a little bit more expense than normal - nonsense - MHRV 6K, Airtightness 10K ........ and the list goes on - its expensive to build passsive - DO NOT KID YOURSELF

c) profession help - there are very few people who fully understand how to build passive - there is so much detail to get sorted out that it costs €€€ of professional help to get it right – you will need an

architect who can give you a good design (its fairly easy to get a box passive but a good design takes skill),
a passive house consultant to do the maths,
engineer to do the structural bit (you will not be building using normal techniques),
an integrated energy consultant to do the heating/Mhrv/solar integration,
a person who can calculate cold bridges and
a very very nice bank manager

d) there is "passive approved products " all come at a premium – that’s more €€€€

So I would suggest you need to reflect on your build and follow my mantra

PASSIVE but keep it PRAGMATIC and PRACTICAL whilst being mindful of PRICE

Good luck

sas · 23-01-2012 12:44PM

Eoghan Barra wrote: »

Sas, I'm very surprised and sorry you seem to be regretting having spent the extra on building in extra insulation and a high level of airtightness etc to get to passive standard.

Surely as well as future savings on heating bills this is to some extent also compensated by the few bob you must have saved by not having to build in a central heating system? And surely it's not only a question of economics, but one of comfort, health and general well-being? And is the question of carbon footprint and each individual's impact on the global environment not also relevant here?

The issue is that the heating system I didn't have to pay for would have cost less than the stove I need to provide hotwater and backup heating in winter. You can't exactly go to waterford for one of this.

I accept the comfort and well being aspect, it should really add to our quality of life.

I don't really care about my carbon footprint. If I did, I wouldn't have built a large concrete house (blocks, concrete floor upstairs, concrete stairs etc) 5 miles from town.

The PH attraction for me was always lower running costs.

I will say that there has never been a better time to build a PH in Ireland. I look through the forums and the magazines and am very jealous of the availability of the systems and knowledge now. I should underline wide cavity was in it's infancy when I started on my journey, this would absolutely be cheaper than the EWI route that I went. With Irish PH certified windows available etc., you could make a real go of it for alot less than we've payed out.

So in summary my recipe for success the 2nd time around:
1. Get PHPP done, forget about certification.
2. Build wide cavity block structure. TF is great, wide cavity is cheaper.
3. Buy windows locally made i.e. PH certification optional
4. Go with rising walls and standard strip foundation system or locally made insulated raft. That german one I imported while great was SOoo expensive.
5. Install HRV system (probably same one I have now).
6. Install oil\lpg backup heating\dhw system
7. Room heating stove only, no PH mandated flue dampers etc
8. Smaller solar array and tank.
9. Install 1 electric shower in the house due to 8.
10. Consider monopitch roof (if planners allowed)
11. Go for a design, not a box shape. It's a home at the end of the day, not a building.
12. Go for a smaller house, divorce not withstanding.
13. Use the same carpenter\foreman. He is the only thing keeping me sane.
14. Take less than 2.5 years to build it

kboc · 23-01-2012 01:50PM

Very honest and great to see somebody acknowledging areas where improvements can be made SAS.

Some questions;

Build wide cavity block structure. TF is great, this is cheaper

Slightly confused, is the TF cheaper than block?

Smaller solar array and tank

Does the PHPP software not dictate the square meterage here.

Consider monopitch roof (if planners allowed)

Is this a aesthetic reason or something which will help passive design/solar array?

Thanks
K

sas wrote: »

The issue is that the heating system I didn't have to pay for would have cost less than the stove I need to provide hotwater and backup heating in winter. You can't exactly go to waterford for one of this.

I accept the comfort and well being aspect, it should really add to our quality of life.

I don't really care about my carbon footprint. If I did, I wouldn't have built a large concrete house (blocks, concrete floor upstairs, concrete stairs etc) 5 miles from town.

The PH attraction for me was always lower running costs.

I will say that there has never been a better time to build a PH in Ireland. I look through the forums and the magazines and am very jealous of the availability of the systems and knowledge now. I should underline wide cavity was in it's infancy when I started on my journey, this would absolutely be cheaper than the EWI route that I went. With Irish PH certified windows available etc., you could make a real go of it for alot less than we've payed out.

So in summary my recipe for success the 2nd time around:
1. Get PHPP done, forget about certification.
2. Build wide cavity block structure. TF is great, this is cheaper.
3. Buy windows locally made i.e. PH certification optional
4. Go with rising walls and standard strip foundation system or locally made insulated raft. That german one I imported while great was SOoo expensive.
5. Install HRV system (probably same one I have now).
6. Install oil\lpg backup heating\dhw system
7. Room heating stove only, no PH mandated flue dampers etc
8. Smaller solar array and tank.
9. Install 1 electric shower in the house due to 8.
10. Consider monopitch roof (if planners allowed)
11. Go for a design, not a box shape. It's a home at the end of the day, not a building.
12. Go for a smaller house, divorce not withstanding.
13. Use the same carpenter\foreman. He is the only thing keeping me sane.
14. Take less than 2.5 years to build it

sas · 23-01-2012 02:06PM

kboc wrote: »

Slightly confused, is the TF cheaper than block?

My bad, quailty TF will be more expensive than wide cavity. I've corrected my previous post to reflect this.

kboc wrote: »

Does the PHPP software not dictate the square meterage here.

If you're not going for certification it doesn't dictate anything, it may give an indication.

kboc wrote: »

Is this a aesthetic reason or something which will help passive design/solar array?

I think it would be cheaper to construct, insulate and airtighten. Plus they do look cool!
Granted it would introduce a bloody great big headache regarding the installation of the hrv. Attics do offer certain practicalities.

Do-more · 23-01-2012 03:06PM

Regarding the solar panels, it will probably be juggling with your Part L requirements which will dictate the minimum amount of solar panels you will use.

DHW is one area of planning which IMO is real finger in the air stuff. Different households can have vastly differing hot water usage and indeed a family's usage can alter as kids grow up or if the family expands.

If I had known last year I would have put an energy monitor on our hot water tank as at present all our water is supplied by an electric immersion but from working back on our electricity bills I estimate that it is between 2500 and 3000kWh per year.

On one level PHPP agrees with this as it estimates DHW usage at a rate of 750kWhr/person/year but because of the size of our house it estimates occupancy at 5.6 people so it bases all it's calculations on a demand of 4200kWhr/a rather than 3000kWhr/a.

In any case once you go over a certain size of solar panels you will be fully meeting your hot water demand in the summer months and adding additional panels gives you a rapidly decreasing return as you will be dumping all your excess summer production.

It will vary with each installation depending on the optimisation of the panels, their performance rating and the anticipated demand but I would guess that around 60 good quality vacuum tubes is the economic sweet spot for a family of four.

Eoghan Barra · 23-01-2012 10:14PM

sas wrote: »

Buy windows locally made i.e. PH certification optional

Why is it so much better to buy ph (standard, not cert.) windows made in Ireland? Have many people had bad experiences getting them from abroad, for example the UK? What are the potential problems in getting them from abroad - lack of back-up service etc?

Also, is it true that a dedicated wood burning stove (ie not multifuel) will satisfy part L of the regs?

sas · 24-01-2012 10:30AM

Eoghan Barra wrote: »

Why is it so much better to buy ph (standard, not cert.) windows made in Ireland? Have many people had bad experiences getting them from abroad, for example the UK? What are the potential problems in getting them from abroad - lack of back-up service etc?

Also, is it true that a dedicated wood burning stove (ie not multifuel) will satisfy part L of the regs?

Most (if not all) of the Irish agents for foreign PH windows are small 1-2 man operations. They were probably selling double glazing at one point, then heatpumps for a while and now PH windows.

You are buying from them i.e. your warranty is with them. If they go under the manufacturer is unlikely to deal with you. One of the better known PH windows agencies changed hands in Ireland last year.

In my case the agent had been poorly trained by the manufacturer. I found more things wrong after they'd snagged than they fixed and I know SFA about windows. I made the mistaken of buying from a company knowing I was going to be their 2 or 3rd customer. I assumed the germans would have trained them properly.

I've had my crowd back 3 times already to make adjustments to windows that were sticking and they are due back again this week to address yet more issues.

If I was buying again I'd make sure that whoever I was buying from was easy to bring to court if needs be, so to me that means buy Irish.

If you buy from abroad you need to be aware of the local practises. For example, it appears to be standard practise for German window companies to ship glazing and frames seperately i.e. the glazing is site installed and hence and sealing (siliconing etc) is done on site.

I can't answer the stove question I'm afraid.

sydthebeat · 24-01-2012 11:12AM

Eoghan Barra wrote: »

Also, is it true that a dedicated wood burning stove (ie not multifuel) will satisfy part L of the regs?

a dedicated wood stove is considered a renewable energy source and contributes towards Part L compliance.
Multi fuel does not.

Whether the stove alone meets the requirement can only be found out by assessment.

JPJ · 24-01-2012 12:44PM

How do you prevent a thermal bridge where a concrete post is bolted to the concrete raft? Is it necessary?
The steel posts sit in the cavity and support steel beams which are supporting hollowcore, and concrete lintels over windows. So the steel post base plate is sitting in the cavity on a uninsulated concrete raft foundation. Therfore, it may draw in cold from outside the insulated envelope.

So what material can I sit the posts on to stop cold transferring from the raft to the post.

Is it enough just to wrap the post in insulation? I do not think so, but not an expert. What do you think?

beyondpassive · 24-01-2012 01:42PM

JPJ wrote: »

How do you prevent a thermal bridge where a concrete post is bolted to the concrete raft? Is it necessary?

As steel is such a good conductor and is supporting 'warm side structure, you need to insulate the raft and make it warm too.

JPJ wrote: »

The steel posts sit in the cavity and support steel beams which are supporting hollowcore, and concrete lintels over windows. So the steel post base plate is sitting in the cavity on a uninsulated concrete raft foundation. Therfore, it may draw in cold from outside the insulated envelope.

Too bad, but perhaps you can wrap the post in high performance insulation, if its a 90 PFC in the centre of a 200 cavity you can encase it in 50mm PIR for example.

JPJ wrote: »

So what material can I sit the posts on to stop cold transferring from the raft to the post.

You could ask your engineer to look at a few layers of neoprene isolator with plastic spacers and SS holding down bolts or even a schock connection http://www.schoeck.co.uk but its likely to be prohibitive on the cost side.

JPJ wrote: »

Is it enough just to wrap the post in insulation? I do not think so, but not an expert. What do you think?

completely depend on the application, what heat demand figure are you designing or building to?

Eoghan Barra · 24-01-2012 02:53PM

Sas and Sydthebeat,

Thanks a lot for your replies.

I was planning on ordering windows from the UK, but I'm having a serious change of heart now.

Sas (or anyone else in the know), would you mind sending me a pm naming the Irish companies you would consider buying passive standard (not cert.) windows off if you were in that position now?

Cheers.

sas · 24-01-2012 03:19PM

Eoghan Barra wrote: »

Sas (or anyone else in the know), would you mind sending me a pm naming the Irish companies you would consider buying passive standard windows off if you were in that position now?
Cheers.

I'd consider the unthinkable

Apparently the window is very good, doors less so from an airtightness point of view.

I'd consider a good double glazed rather than a triple glazed window to be honest. The premium on passive windows etc is simply too high. My brother in law bought what appears to be a good quality (but bog standard) pvc window for his build. 96m2 for 26k, mine were 42k for 60m2. Comparison isn't directly comparable but that money speaks volumes.

Simple maths:

If you assumed identical structures with the exception of the glazing as above, I spent\borrowed 16k (42k - 26k) more. We'll ignore the fact that there is a 50% difference in the area of what was purchased.

So, over 30 years I'll have spent 32k (16k approximately doubles with interest) more.

So break even savings needs to be approx €1066 per year between the window specs.

I'm not seeing it personally.

JPJ · 24-01-2012 04:23PM

My BER report states that the house has a primary energy demand of 73 kWh/m2/year with C02 emissions of 18 kg/m2/year. Is this what you are asking for?

Some of the details of the build, the estaimted U values are from the BER report.
House is a two-storey room in roof/dormer style. A cross shape, which unfortunately means most rooms have 3 external walls. Too late before I relaised the implications. Most windows are south facing. Only 1 North facing.
• Concrete raft foundation - un-insulated unfortunately BUT 200 mm underfloor
• 350 mm Cavity block wall: 100mm - 250mm cavity - 100mm. (U = .15)
• Quinn lite Foundation block as first course on the internal wall.
• Wall Ties are Ancon Low Thermal Conductivity
• Under-floor Insulation = 200mm
• Roof 150mm Kingspan Kooltherm K7 between rafters and 72.5mm Kooltherm K17 under the rafters ( U = 0.12). However I am considering going with a foam between rafters for better air-tightness - and using a thicker insulated board under the rafters to compensate to meet the required U value
• Windows & Doors - most likely with U = .8 (Recall the doors have same U but not sure right now)
• Also 12 Velux windows in the roof - most likely triple glazed - but fast running out of cash
• Plan to have Air-tight tape on doors & windows, but relying on the plaster for air-tightness on the blocks hopefully achieving less than 3 ach - but not sure what is possible with block construction. No dry lining of blocks.
• Heat Recovery Ventilation

This house has been planned for some time, I was familiar with the Passive concept, but very few of my advisers were so we are not going for Passive Certification for which I now regret, but still hope to push as far as we can afford and makes sense.

There are 7 steel posts in the house. So is it worthwhile spending maybe €300 or €400 or maybe more getting these Schock thermal plates or similar?

kboc · 24-01-2012 04:26PM

Eoghan Barra wrote: »

Sas and Sydthebeat,

Thanks a lot for your replies.

I was planning on ordering windows from the UK, but I'm having a serious change of heart now.

Sas (or anyone else in the know), would you mind sending me a pm naming the Irish companies you would consider buying passive standard (not cert.) windows off if you were in that position now?

Cheers.

PM sent

beyondpassive · 24-01-2012 04:54PM

JPJ wrote: »

My BER report states that the house has a primary energy demand of 73 kWh/m2/year with C02 emissions of 18 kg/m2/year. Is this what you are asking for?

Some of the details of the build, the estaimted U values are from the BER report.
House is a two-storey room in roof/dormer style. A cross shape, which unfortunately means most rooms have 3 external walls. Too late before I relaised the implications. Most windows are south facing. Only 1 North facing.
• Concrete raft foundation - un-insulated unfortunately BUT 200 mm underfloor
• 350 mm Cavity block wall: 100mm - 250mm cavity - 100mm. (U = .15)
• Quinn lite Foundation block as first course on the internal wall.
• Wall Ties are Ancon Low Thermal Conductivity
• Under-floor Insulation = 200mm
• Roof 150mm Kingspan Kooltherm K7 between rafters and 72.5mm Kooltherm K17 under the rafters ( U = 0.12). However I am considering going with a foam between rafters for better air-tightness - and using a thicker insulated board under the rafters to compensate to meet the required U value
• Windows & Doors - most likely with U = .8 (Recall the doors have same U but not sure right now)
• Also 12 Velux windows in the roof - most likely triple glazed - but fast running out of cash
• Plan to have Air-tight tape on doors & windows, but relying on the plaster for air-tightness on the blocks hopefully achieving less than 3 ach - but not sure what is possible with block construction. No dry lining of blocks.
• Heat Recovery Ventilation

This house has been planned for some time, I was familiar with the Passive concept, but very few of my advisers were so we are not going for Passive Certification for which I now regret, but still hope to push as far as we can afford and makes sense.

There are 7 steel posts in the house. So is it worthwhile spending maybe €300 or €400 or maybe more getting these Schock thermal plates or similar?

So its an A3 house, plaster is fully airtight as long as you seal it at all interfaces with other materials. I'd aim for an airtighness of 1 as it sets a high bar for workmanship and will help the efficiency of your MHRV Where you have rooms in the roof, I'd prefer natural materials, although it costs extra, materials like softboard and cellulose, which have better heat retention capacity than lightweight polmer based insulations which have some resistance to heat but no thermal lag propeerties I wouldn't use spray foam unless I had an hygrothermal analysis carried out which shows how it performs when sprayed against the breather membrane.

You'd have to show a detail of where the steel posts are located relative to the cavity and also relative to openings, in order to see what is the best way to keep them warm.

beyondpassive · 24-01-2012 05:59PM

Eoghan Barra wrote: »

Sas (or anyone else in the know), would you mind sending me a pm naming the Irish companies you would consider buying passive standard (not cert.) windows off if you were in that position now?

Cheers.

PM sent,

In going from mere building reg standard to passivhaus you make a series of interventions to improve the efficiency and comfort of the building. These are justified on a cost benefit balance which includes the compound cost of finance but also includes a conservative estimate of projected fuel costs at 6%. A time horizon of 20 years is set as some items will need replacing. For instance on one particular build:

(Some intentions cost less than others, design improvements cost virtually nothing, but we'll ignore this one as design is most often ignored in the interest of getting planning quickly and cheaply).
-Extra insulation, airtightness below 1, MHRV can have a payback of 7 years,
-solar store- 8 years
-thermal bridge free junctions 12 years. All easily justified.

Windows are a different matter, treble glazing alone costs very little above double so its really about the frame. You can have treble glazed in a cheap 1.4 U-Value frame and it will pay back in 10-12 years. But for good surface temperature comfort and condensation risk reduction the frame should be thermally broken, The top end windows have a cork core wheras the new cheaper passivhaus windows have a layer of insulation behind the aluclad. The former can be twice as much costwise as the latter, but in truth they look it. I'd love to use I..m or P..n the Bose sound system of windows, but instead use one of 3 cheaper systems, 2 of which are also imported, only 1 is a small operation they are T..e, H..r and M..y. The high end stuff looks like it would last forever but the sales and service guys are all bluster and it can be infuriating getting them to rectify installation issues. The mid range stuff is fit for purpose, but without paying a such a high premium you get better service.

So what about Passivhaus? You get so many people building one off's that were planned before they ever heard of passivhaus. I would never even suggest these guys set their hearts on a cert unless they have a build as compact as a crate and able to catch all the winter sun. As SAS, Fclauson and I found out independently, the cost benefit sweet spot for irish detached typology is around 17-20kWh, depending on location and shape, whereas you need to be at least 13.5kWh/m2 for passivhaus. So If your going certified passivhaus, you really should go for the high end windows, certified passivhaus with tilt and slide doors which can be upwards of €20k above a mid range thermally broken window.

That last intervention is a game changer for most builds. Its a lot of money for 3 or 4 kilowatts a €50 annual running cost saving and a snazzy glass plaque Its a frying pan over the head for the decision maker, if the slider jams after you've moved in. These windows are the bugatti Veyron of the fenistration world, as long as they're not serviced by your backyard mechanic.

Great credit to SAS and Syd for a fantastic Passivhaus, it really is a joy to visit it on a sunny december morning. However, at least You didn't put as much money into the build as this guy: http://www.youtube.com/watch?v=beK0O25O9aY#video

JPJ · 24-01-2012 07:11PM

beyondpassive, here are the steel details

Can you PM the window details to me too please?

Eoghan Barra · 24-01-2012 08:49PM

sas wrote: »

I'd consider the unthinkable

Apparently the window is very good, doors less so from an airtightness point of view.

Thanks for that, sas. I presume you're talking about MJ?

Thanks beyondpassive and kboc for your pms; you both actually mentioned the same company, which means they definitely must be worth checking out. Nice one.

fclauson · 24-01-2012 09:26PM

beyondpassive wrote: »

... However, at least You didn't put as much money into the build as this guy: http://www.youtube.com/watch?v=beK0O25O9aY#video

I have to call this out - think of the dinner party comments "so how much did it cost to build this place" !!!!!:D

fclauson · 24-01-2012 09:30PM

JPJ wrote: »

My BER report states that the house has a primary energy demand of 73 kWh/m2/year with C02 emissions of 18 kg/m2/year. Is this what you are asking for?

At these levels of insulaiton you have to do a PHPP (or dig into the DEAP spread sheet version to extract numbers from the ER1 sheet) to get under these figures

H/W and elec at these levels can really damage you BER rating and give meaningless numbers for heat demand

portwest · 24-01-2012 10:35PM

sas wrote: »

The issue is that the heating system I didn't have to pay for would have cost less than the stove I need to provide hotwater and backup heating in winter. You can't exactly go to waterford for one of this.

I accept the comfort and well being aspect, it should really add to our quality of life.

I don't really care about my carbon footprint. If I did, I wouldn't have built a large concrete house (blocks, concrete floor upstairs, concrete stairs etc) 5 miles from town.

The PH attraction for me was always lower running costs.

I will say that there has never been a better time to build a PH in Ireland. I look through the forums and the magazines and am very jealous of the availability of the systems and knowledge now. I should underline wide cavity was in it's infancy when I started on my journey, this would absolutely be cheaper than the EWI route that I went. With Irish PH certified windows available etc., you could make a real go of it for alot less than we've payed out.

So in summary my recipe for success the 2nd time around:
1. Get PHPP done, forget about certification.
2. Build wide cavity block structure. TF is great, wide cavity is cheaper.
3. Buy windows locally made i.e. PH certification optional
4. Go with rising walls and standard strip foundation system or locally made insulated raft. That german one I imported while great was SOoo expensive.
5. Install HRV system (probably same one I have now).
6. Install oil\lpg backup heating\dhw system
7. Room heating stove only, no PH mandated flue dampers etc
8. Smaller solar array and tank.
9. Install 1 electric shower in the house due to 8.
10. Consider monopitch roof (if planners allowed)
11. Go for a design, not a box shape. It's a home at the end of the day, not a building.
12. Go for a smaller house, divorce not withstanding.
13. Use the same carpenter\foreman. He is the only thing keeping me sane.
14. Take less than 2.5 years to build it

Hi sas,
What heating/dhw system would you recommend to back up with oil/lpg? and why a monopitch roof?

BryanF · 24-01-2012 10:36PM

JPJ wrote: »

beyondpassive, here are the steel details

Can you PM the window details to me too please?

is it too late to put the steels inside the window frames

Tifosi · 24-01-2012 10:52PM

[QUOTE=beyondpassive;76702309

. I'd love to use I..m or P..n the Bose sound system of windows, but instead use one of 3 cheaper systems, 2 of which are also imported, only 1 is a small operation they are T..e, H..r and M..y. The high end stuff looks like it would last forever but the sales and service guys are all bluster and it can be infuriating getting them to rectify installation issues. The mid range stuff is fit for purpose, but without paying a such a high premium you get better service.

[/QUOTE]

I think I know who the first two window companies are, the latter three I have no idea, I would be grateful if some could send me a PM to enlighten me.

How about N...n

BryanF · 24-01-2012 10:56PM

beyondpassive wrote: »

So If your going certified passivhaus, you really should go for the high end windows, certified passivhaus with tilt and slide doors which can be upwards of €20k above a mid range thermally broken window.

as the guinea pigs (no personal attacks intended) you and others are pushing the building standards of 'low energy homes' - are we not now seeing an increase in the quality of the components and prices coming down?
and is the lack of industry training and 'giving a hoot' / the allowance for such crap on the market, that has caused the purchaser to pay part of this increased premium for quality - what is the PH window premium in Germany for instance?
also have any of ye looked into using an unheated porch or 'sunspace' as a buffer to reduce the spec of the PH rated window/door units? (i appreciate this in its self is an extra cost, but you do get a few watts in the BER for your porch, woohoo!)

JPJ · 24-01-2012 11:03PM

BryanF wrote: »

is it too late to put the steels inside the window frames

BryanF, If you mean that the window will be side by side with or overlap the steel, and there will be a covering over the steel that matches the window, yes I think we are doing that. If you mean something else, please describe again.

Assuming we both have the same understanding, then, the problem I am afraid of is that the steel post will be connected to cold and uninsulated raft foundation, making everyting colder than it might otherwise be. That steel post is not only supporting the window, it rises to support an over window steel beam that supports other elements, hollowcore, walls, etc.

Building methods for passiv standard?

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