Passive building

abots

We just got a quote for a passive build for our 2 storey, 259.37 sqm home and I'm wondering is it good value. Its for...

Super grund low energy foundation 0.1W2mk, with external wall 200mm platinum filled cavity concrete block 100/200/100,500mm cellous filled in attic. Fully finished. 223,689 after tax.

Also wondering will solar panels be enough as a source of heating house and water?

Do-more

abots wrote: »

Also wondering will solar panels be enough as a source of heating house and water?

No. Solar will only supply a tiny fraction of your hot water and no space heating in the Winter months.

My advice would be to get a PHPP done now to assess your design at this stage as if you are asking this question you obviously haven't had one done yet. It is definitely worthwhile and I would say the best investment I have made on my house so far.

kboc

PM sent. That price is far too high even for a passive build.

abots

Thanks for the help. Do I get the PHPP info off Sustainable Energy Ireland?
I've also contacted Galway Energy Agency.

As you can guess we have only just decided to build this way and I'm still very much in the dark.

bruschi

kboc wrote: »

PM sent. That price is far too high even for a passive build.

its €80 a square foot after VAT. without knowing any specs whatsoever on the scope of the works involved, it is absolutley impossible to tell if it is far too high at all. To be honest, it doesnt seem far too high at all to me.

it seems a reasonable price for a fully finished house, but what is fully finished? what is the level of detail to the finish?

to be honest, it'd be like me coming on here and saying I am buying a BMW car for €25,000, is it good value?

without knowing the full details it is literally impossible to say if it is good value. Good value can only be determined by the end user. Some pople will want a bigger level of detail on some things, and others wont, as they cant afford it. Value is about getting the best for the money you can afford ot spend on a project.

Dont get sucked into costs per square metre, or measuring it against what other people get. Look at individual aspects of the house, and if you get value on each thing, and know you have the best cost for the quality you are getting for a price you can afford, then it will be good value for you.

the other thing, before you start on a passive house, learn as much as you can about it. There is no point in going for a passive house, if thats not what you end up with. Its very easy for a couple of things to slip by, and not get a passivhaus rating. you are better off waiting until you know enough about it before starting.

Carlow52

kboc wrote: »

PM sent. That price is far too high even for a passive build.

That is a completely unsubstantiated claim.
Coupled with a PM I would say beware of posters bearing gifts.

bruschi is on the money here.
OP: its clear you are somewhat out of your depth here so you had better tool up or else recruit some good independent professional advisors

muffler

kboc wrote: »

PM sent. That price is far too high even for a passive build.

Can you confirm for the benefit of everyone here if you have built a house in the Republic of Ireland and you are familiar with pricing for passive house builds here.

Thanks.

abots

As I said we have only just started to think of building passive. The only reason I questioned the quote is because when we first met the builder he assured us we would get the house built for the amount our mortgage is, 170k, its quite a jump...

And I've contacted independent agencies and am waiting for replies. I figured it was no harm asking on here while I waited.

bmm

How about hiring a quantity surveyor? The lady on the RTE programme "A room to improve" , she seems to get her estimates quiet accurate.

Abbreviations should be banned from forums. Let's speak English.:pac:

kboc

muffler wrote: »

Can you confirm for the benefit of everyone here if you have built a house in the Republic of Ireland and you are familiar with pricing for passive house builds here.

Thanks.

Whether I have built none or one is absolutely irrelevant, but when you have spent the hours of research, and spoken to well informed professionals on passive houses that I have, then I can say what I like, once it sits within the rules of Boards.ie. Which to my mind that statement did.

But I'll tell you what I am involved in, (possibly) the first passive school on the island of Ireland.

Republic of Ireland

You know full well i don't live there, I could technically perceive that as a form of discrimination.
I live in the same province as you! But I have a southern accent, does that make a diference?

Adios!

kboc

Carlow52 wrote: »

That is a completely unsubstantiated claim.
Coupled with a PM I would say beware of posters bearing gifts.

bruschi is on the money here.
OP: its clear you are somewhat out of your depth here so you had better tool up or else recruit some good independent professional advisors

That is a completely unsubstantiated claim.
Coupled with a PM I would say beware of posters bearing gifts.

The fact you were not privvy to the content of the PM you can not make that sweeping statement. For your info, my PM was addressing the very point you make. By the way christmas is gone and I am a miserbale git as regards gifts, just ask my missus!

kboc

bruschi wrote: »

its €80 a square foot after VAT. without knowing any specs whatsoever on the scope of the works involved, it is absolutley impossible to tell if it is far too high at all. To be honest, it doesnt seem far too high at all to me.

it seems a reasonable price for a fully finished house, but what is fully finished? what is the level of detail to the finish?

to be honest, it'd be like me coming on here and saying I am buying a BMW car for €25,000, is it good value?

without knowing the full details it is literally impossible to say if it is good value. Good value can only be determined by the end user. Some pople will want a bigger level of detail on some things, and others wont, as they cant afford it. Value is about getting the best for the money you can afford ot spend on a project.

Dont get sucked into costs per square metre, or measuring it against what other people get. Look at individual aspects of the house, and if you get value on each thing, and know you have the best cost for the quality you are getting for a price you can afford, then it will be good value for you.

the other thing, before you start on a passive house, learn as much as you can about it. There is no point in going for a passive house, if thats not what you end up with. Its very easy for a couple of things to slip by, and not get a passivhaus rating. you are better off waiting until you know enough about it before starting.

Yup, I made a mistake.

I seen the 223 figure and presumed it was a price per square foot. Should have red the post again

Sorry for misunderstanding.

muffler

kboc wrote: »

Whether I have built none or one is absolutely irrelevant, but when you have spent the hours of research, and spoken to well informed professionals on passive houses that I have, then I can say what I like, once it sits within the rules of Boards.ie. Which to my mind that statement did.

But I'll tell you what I am involved in, (possibly) the first passive school on the island of Ireland.


You know full well i don't live there, I could technically perceive that as a form of discrimination.
I live in the same province as you! But I have a southern accent, does that make a diference?

Adios!

If you think you are being discriminated against in any way then please feel free to progress the matter further as you normally do.

I moderate this forum along with others and we will decide what is and whats not acceptable here and certainly not you.

The reason I asked for the clarification was because you posted a very, very misleading statement.

Do not derail the thread any further with posting about matters that are of no concern to anyone here.

kboc

muffler wrote: »

If you think you are being discriminated against in any way then please feel free to progress the matter further as you normally do.

I moderate this forum along with others and we will decide what is and whats not acceptable here and certainly not you.

The reason I asked for the clarification was because you posted a very, very misleading statement.

Do not derail the thread any further with posting about matters that are of no concern to anyone here.

If you think you are being discriminated against in any way then please feel free to progress the matter further as you normally do

already done big man!

Do you know you keep leaving you bold key on?

bruschi

kboc wrote: »

Yup, I made a mistake.

I seen the 223 figure and presumed it was a price per square foot. Should have red the post again

Sorry for misunderstanding.

you probably would have been better off posting this post before your other rants to the others! you made a mistake, that pretty much clarifies why others took umbrage to your original post.

beyondpassive

abots wrote: »

Also wondering will solar panels be enough as a source of heating house and water?

I guess when we say Passive or Passivhaus its no longer a lofty aspiration for a building at the zenith of energy efficient performance, after all the 2011 Part L building regulations require passivhaus levels of fabric insulation as a minimum. If you have planning you only need build to 2008 levels. While its possible to build passivhaus at €90 per square foot, the building must have compact design and a low percentage of windows and doors. The big cost in building is the finishes, so natural slate and aluclad windows alone can push a budget up 10%.

I always find its very handy to have your building modelled in PHPP, its an excel spreadsheet and is fairly straightforward. When you add Peter Warm's summary sheet, it can be very useful to see where your heat is being gained and lost and can let you try out a number of heating system configurations.

Recent research by Dr Shane Coughlough, and seperatly by Bill Quigley and \seamus O'Loughlin indicate that it is possible to space heat a passivhaus with solar alone, with an immersion for hot water. But you need an expensive interseasonal store or recirculate the ventilation air.

A passivhaus of about 250sqm would have a space heat load of about 5 to 6KW on the coldest day of last year and a similar hot water load of 4 or 5. The solar can charge your underfloor or put low grade heat in your ventilation system in spring and autumn but for deep winter you'll need a supplimentary heating system. This can be a back boiler stove or a heat pump, but most often is a conventional boiler. The main reason for solar panels is to meet the 10kWh/m2 renewables requirement for part L 2008 and Part L 2011. For large houses, a heat pump alone wont meet the requirement. Generally if you need solar you need a hydrophonic heating system, so you're back to wet plumbing. So its very important to have your heating and ventilation system designed before you send the job for pricing.

BryanF

abots wrote: »

As I said we have only just started to think of building passive. The only reason I questioned the quote is because when we first met the builder he assured us we would get the house built for the amount our mortgage is, 170k, its quite a jump...

quite a jump from what?

think of it like this: were now at a 40% the 2005 BER requirement of circa >155kWh/m2.yr so that puts us at less than say >60 kWh/m2.yr.

• the passive house standard has an Annual space heating requirement of 15 kWh/m2.yr treated floor area.
• the passive house standard requires circa 1/7 of what the current air-tightness building regulations require

while neither of these are a straight forward comparison, I think its fair to say that without your builder having an accurate, detailed set of drawings and specification, to price either to current building regulations or even the passive house standard, your quotations are of a limited nature


I hope i'm not taking this too off topic, as I'm delighted to see a discussion on passive house building but just to follow on from PUT's question can we just clarify:

1. Have you got a price for a 'passive' house without carrying out a PHPP calculation? I'd like the see the caveat under this quotation
2. please tell me this price is pre-planning? so you can at least modify your deign to suit your budget
3. is this a turn key price, directly from your preferred builder? without any independent architecturally/passive house consultant representation, you'd want to trust your builder...

(now i mean 'passivhaus', as opposed to PUT's 'carbon neutral, in design and use house' or as many of our builders like to pretend a 'near passive house' when they actually mean 'I've stuck and extra bit of insulation in there for you luv'

1. a passive house must be designed with reduced heat loss in mind from the beginning - this does not mean you cant have an interesting design - just that energy/heat loss reduction should be a high priority
2. a passive house needs to though-out early on. Ze Germans call this the 'planning stage'. In Ireland this means that there are essentially two planning stages, with the the passive house one coming first. front loading the design process prior to planning increases your initial design expensive but the idea is this saves you in compromising/ altering at the tender and construction stages when the design is fixed by your local authority planning permission.
3. an arch and nowadays a QS will save you money in the long run + take some of the strain out of the process on your behalf

brophis

In the process of building a low energy house myself and that price to me seems reasonable for a passive house but as stated it's all in the finer details.

after all the 2011 Part L building regulations require passivhaus levels of fabric insulation as a minimum

BryanF wrote: »

think of it like this: were now at a 40% the 2005 BER requirement of circa >155kWh/m2.yr so that puts us at less than say >60 kWh/m2.yr.

• the passive house standard has an Annual space heating requirement of 15 kWh/m2.yr treated floor area.
• the passive house standard requires circa 1/7 of what the current air-tightness building regulations require

while neither of these are a straight forward comparison, I think its fair to say that without your builder having an actuate, detailed set of drawings and specification, to price either to current building regulations or even the passive house standard, your quotations are of a limited nature

I've been messing around with the DEAP software to see what effect different u-values have on the heating requirements of a house and a few things dawned on me. Lets take the A3 house with 60kWh/m2.yr for example, depending on air tightness and thermal bridging ~20-25kWh/m2.yr, is required for space heating. (What I found odd was that ~14kWh/m2.yr was due to an electricity "overhead" that's out of my control!). Granted DEAP isn't using same calculations as PHPP but as far as building fabric goes the new regulations are not far away from passive. The major difference now is the air tightness levels and thermal bridging details, both of which are the major difference in cost between meeting building regulations and getting near passive. For example, having a highly airtight house mean MHRV which is more capital outlay but the long term benefit is what its all about.

I think the moral of the story is that it's no longer about u-values but we're heading in the right direction. The better the building regs the more expensive it's getting to build but it's costing less to heat the house.

Do-more

beyondpassive wrote: »

research by Dr Shane Coughlough, and seperatly by Bill Quigley and \seamus O'Loughlin indicate that it is possible to space heat a passivhaus with solar alone, with an immersion for hot water. But you need an expensive interseasonal store or recirculate the ventilation air.

Do you have any links to support that?

From what I have read on the subject the jury is very much still out.

Lars Pettersson will freely admit that the seasonal store he built in Galway has performed well below his expectations due to heat losses from the store, running out of useful heat by the end of December last year.

Unless I am mistaken the solar slabs that Seamus has constructed have not yet been in use for a full heating season so I think it is still a little early to say that it is possible to heat a house in this way.

Irrespective of whether the technology is proven or not it's worth pointing out that when you talk of "expensive seasonal stores" we are talking in terms of tens of thousands of euro of an investment (I think Lars' cost €55k from memory) in order to save a heating bill of maybe €400.

I'm not knocking the research, it's only from trying these things out that we will ever find affordable solutions.

But for the normal home owner the reality is we are no where near being able to economically heat our homes with solar energy alone.

beyondpassive

Do-more wrote: »

Do you have any links to support that?

yes the jury is very much still out.

The link from the see the light 2011 conference is out, you could contact Dr Shane Colclough at Energy Expertise directly.

I don't believe you can get a completely solar heated house to be economical in our climate, however if you are required to have 60 or 80 tubes you will produce about 4000kWh of hot water, and only use about 1500kWh, so it makes sence to investigate ways of utilising this. My preference is 1000L stratified buffer with plate heat exchanger to underfloor. That way in a high thermal capacity building, you can use the waste solar heat to charge the structure up to comfort levels.

brophis

beyondpassive wrote: »

I don't believe you can get a completely solar heated house to be economical in our climate, however if you are required to have 60 or 80 tubes you will produce about 4000kWh of hot water, and only use about 1500kWh, so it makes sence to investigate ways of utilising this. My preference is 1000L stratified buffer with plate heat exchanger to underfloor. That way in a high thermal capacity building, you can use the waste solar heat to charge the structure up to comfort levels.

At present this is on top of my list due to the fact that I need a large solar array to meet the Part L renewable requirements. Plan to have the solar feeding a 1000L buffer tank with ufh off the middle of the tank. Planning to use oil to heat up the top of the tank as needed for dhw. My only concern is if this will keep the middle of the tank at a high enough temp for the ufh when the solar isn't contributing (today there's some good solar gain and flat panels hitting 40C in parents house). Has anyone with a similar system got any feedback on this? Would a plate heat exchanger be a better option than a direct feed to the tank?

Edit: Been looking into this a bit further and I think the way to go is have the option of mixing water from top of tank with middle if needed?

about2build

I was given a quote of 285,000 to build a 2550 sq ft house to passive levels so based on the difference in size to yours I'd say your quote is pretty good....comment about solar space heating worrying though as it will do hot water during late spring summer and early autumn months (60-70%) of same but will not contribute to space heating and in the winter you will get very little of either from it....my two pence worthg but some contributors on here like beyondpassive are the ones who really know their potatoes

clansman

about2build wrote: »

I was given a quote of 285,000 to build a 2550 sq ft house to passive levels so based on the difference in size to yours I'd say your quote is pretty good....comment about solar space heating worrying though as it will do hot water during late spring summer and early autumn months (60-70%) of same but will not contribute to space heating and in the winter you will get very little of either from it....my two pence worthg but some contributors on here like beyondpassive are the ones who really know their potatoes

Does that included fully furnished? eg beds, TV, mirrors...etcc

I am thinking of building a passive house but we have most a lot of appliances and furniture all ready.

about2build

excluding appliances and any furnishings!

beyondpassive

Are those prices with or without Vat at 13.5%, it catches people out.

Its worth noting also that it now almost irrelevent to talk about basic standard and Passivhaus standard as the levels of Fabric U-Values for any houses applying for planning permission since December 2011 are practically equivalent to Passivhaus levels. The only difference is airtighness and of course the quality control checks needed for passivhaus. I would have addedt MHRV as a difference between standard and passivhaus, but MHRV is pretty much standard kit for new build detached houses complying with Part L 2008.

kboc

1000L stratified buffer with plate heat exchanger to underfloor

beyondpassive,

Do you have any web links explaining how these work?
What sort of price are they?
Is the associated plumbing similar to a triple coiled tank?

Regards
K