Advertisement
If you have a new account but are having problems posting or verifying your account, please email us on hello@boards.ie for help. Thanks :)
Hello all! Please ensure that you are posting a new thread or question in the appropriate forum. The Feedback forum is overwhelmed with questions that are having to be moved elsewhere. If you need help to verify your account contact hello@boards.ie

Building methods for passiv standard?

Options
13»

Comments

  • Options
    #62
    Choolips
    Registered Users Posts: 6 ✭Choolips


    Hi Beyondpassive and kboc,

    Could you send me on you window supplier recommendations too? Thanks v much!


  • Options
    #63
    keru
    Registered Users Posts: 27 ✭keru


    Hi Beyondpassive and kpoc ,
    Could you also PM me your window recommendations?
    Am I correct in understanding that the difference between a good window with a thermally broken frame and a Certified passive window is only in the order of 5 to 10 Kw energy consumption saving over the year?


  • Options
    #64
    sas
    Registered Users Posts: 1,282 ✭✭✭sas


    Eoghan Barra wrote: »
    Thanks for that, sas. I presume you're talking about MJ?

    Yes, I am.


  • Options
    #65
    sas
    Registered Users Posts: 1,282 ✭✭✭sas


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

    Stove of some sort. Possibly a room heating (i.e. no back boiler) stove. The boiler stoves that are suitable for low energy houses are big money e.g. 5k for the one I'm looking at.

    Solar for hot water when possible. Electric shower somewhere in the house to cover times when there is no viable solar but the weather is too mild to have oil\lpg running.

    I like monopitch roofs. I'd do it as part of an overall design. I went for a box to keep the construction complexity down and also with the hope it would be cheaper. I don't think our home would ever be described as have "kerb appeal".


  • Options
    #66
    beyondpassive
    Registered Users Posts: 558 ✭✭✭beyondpassive


    keru wrote: »
    Am I correct in understanding that the difference between a good window with a thermally broken frame and a Certified passive window is only in the order of 5 to 10 Kw energy consumption saving over the year?

    kW is the SI unit for load or power, usage or demand is in Kwh's. Passivhaus used kWh/sq.m to measure demand. So 15kWh/m2 x 250 = 3,750kWh for space heating alone. If a lesser quality window and door frame is used this might go out to 17kWh/m2 which is 4,250kWh. Simplified 500kWh costing 10cent per kWh with LPG incl standing charges and VAT is €50 euro extra running charges.
    portwest wrote: »
    Hi sas,
    What heating/dhw system would you recommend to back up with oil/lpg? and why a monopitch roof?

    Can I butt in! attached below is the schematic of the heating system with Thermal Store, we generally use for Ultra low energy homes. Its a lot of kit, but its made of simple components and the lower 40 degree halp of the tank diverts spare solar heat into the structure. Can be up to a 1,000kWh free solar heat into the space heating. Even in summer we can have put our overheat into the wetroom underfloor circuit for comfort and humidity control. The logic of this system is, you've done the hard yaka of lowering your heat demand to the minimum within your budget constraints. You've got a big solar array, and buffer tank to comply with Part L, lots of 36degree water, perfect for low grade heat, your MHRV wants a constrant 19 degrees year round, and you couldn't be arzed importing seasoned timber and cleaning stoves. Simples.
    passivhaus heating.jpg


  • Advertisement
  • Options
    #67
    BryanF
    Moderators, Home & Garden Moderators Posts: 10,140 Mod ✭✭✭✭BryanF


    JPJ wrote: »
    Also 12 Velux windows in the roof - most likely triple glazed - but fast running out of cash
    id be as worried about the heat loss from these 12!! rooflights as much as the thermal bridges from the steel posts


  • Options
    #68
    BryanF
    Moderators, Home & Garden Moderators Posts: 10,140 Mod ✭✭✭✭BryanF


    JPJ wrote: »
    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.
    if the steel posts are not already fitted why not place the steel posts 'room side' of the windows, inside the thermal envelope. where the windows are butted to the steel (steel in-line with the wins) and insulation space maybe a problem for the cover flashing, consider using aerogel


  • Options
    #69
    sas
    Registered Users Posts: 1,282 ✭✭✭sas


    beyondpassive wrote: »
    Can I butt in! attached below is the schematic of the heating system with Thermal Store, we generally use for Ultra low energy homes. Its a lot of kit, but its made of simple components and the lower 40 degree halp of the tank diverts spare solar heat into the structure. Can be up to a 1,000kWh free solar heat into the space heating. Even in summer we can have put our overheat into the wetroom underfloor circuit for comfort and humidity control. The logic of this system is, you've done the hard yaka of lowering your heat demand to the minimum within your budget constraints. You've got a big solar array, and buffer tank to comply with Part L, lots of 36degree water, perfect for low grade heat, your MHRV wants a constrant 19 degrees year round, and you couldn't be arzed importing seasoned timber and cleaning stoves. Simples.
    passivhaus heating.jpg

    I'm playing with the idea of not buying a back boilered stove and instead going with a room heating one. Spending the savings on an lpg boiler.

    It would likely cost less than the boiler stove I'm looking at but would offer alot more control i.e. you can't set a solid fuel stove to come on an hour before you get home.

    I'd really like to see what the solar will actually contribute before I do this. We're likely to get the chance too because we're moving in in April and I don't think we'll be able to afford the stove until August!


  • Options
    #70
    Do-more
    Registered Users Posts: 4,748 ✭✭✭Do-more


    sas wrote: »
    Electric shower somewhere in the house to cover times when there is no viable solar but the weather is too mild to have oil\lpg running.

    What about hot water demand other than showers? Will you be washing pot & pans with lukewarm water?

    BTW Have you gone for hot fill appliances?

    invest4deepvalue.com



  • Options
    #71
    sas
    Registered Users Posts: 1,282 ✭✭✭sas


    Do-more wrote: »
    What about hot water demand other than showers? Will you be washing pot & pans with lukewarm water?

    BTW Have you gone for hot fill appliances?

    Showers would be by far our largest immediate hot water need. If I have a large number of dishes to wash then the dish washer will be used. I would only purchase one that heats it's own water with an option for a hot feed if possible. I'm open to correction here but I've not seen warm fill as an option commonly available in the last few years.

    If I need a little hot water to wash a few items I'll boil a kettle, this wouldn't work for showering for obvious reasons.


  • Advertisement
  • Options
    #72
    fclauson
    Registered Users Posts: 1,691 ✭✭✭fclauson


    sas wrote: »
    I'm playing with the idea of not buying a back boilered stove and instead going with a room heating one. Spending the savings on an lpg boiler.

    It would likely cost less than the boiler stove I'm looking at but would offer alot more control i.e. you can't set a solid fuel stove to come on an hour before you get home.

    I'd really like to see what the solar will actually contribute before I do this. We're likely to get the chance too because we're moving in in April and I don't think we'll be able to afford the stove until August!

    SAS as I have said before - this is a good plan - LPG works on the button - every time - does not complain - does not need to have timber sawn up for it - does not mean going out in the snow to get more logs etc etc etc


  • Options
    #73
    Do-more
    Registered Users Posts: 4,748 ✭✭✭Do-more


    sas wrote: »
    I'm open to correction here but I've not seen warm fill as an option commonly available in the last few years.
    I can't say for sure myself but I did have a conversation with an architect about them last year, but when he mentioned that they were 2-3 times the cost of basic appliances and stressed the need to consider the cost as part of an holistic approach, I kind of tuned out! :pac:

    invest4deepvalue.com



  • Options
    #74
    sas
    Registered Users Posts: 1,282 ✭✭✭sas


    fclauson wrote: »
    SAS as I have said before - this is a good plan - LPG works on the button - every time - does not complain - does not need to have timber sawn up for it - does not mean going out in the snow to get more logs etc etc etc

    And I'm leaning even further away from my original plans now. I don't like the idea of being tied into a contract with one of the LPG suppliers unless it's very short. I await a response from 1 of them on this question, the person I spoke to didn't know!

    Then I decided to look at internal oil boilers with balanced flue. I can buy a 15 - 21kw unit for €1300 (list price). I won't be tied to any contract. It would easily have the power to heat my 1000 litre tank. I'm hearing that smells are alot less of an issue with the modern balanced flue models.

    In time I might add a dry stove or even the original stove or similar depending on how successful the oil set up is.


  • Options
    #75
    just do it
    Registered Users Posts: 5,422 ✭✭✭just do it


    What I'm taking from this thread (and what I've read on another thread regarding new building regs) is the deciding factor on going passiv or not is the window and door spec.

    There is a positive cost benefit on all other elements i.e. design, low u-value foundations, walls and roof, airtightness to less than 0.6 ACH & MHRV, detailing out thermal bridging. The cost of windows and doors however just isn't justifiable on financial grounds. Of course this might change with one or two new Irish entrants with passiv spec windows and doors!

    (1 being provincial and the other being smart;-) )


  • Options
    #76
    BarneyMc
    Registered Users Posts: 1,504 ✭✭✭BarneyMc


    BryanF wrote: »
    1. 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!)

    This is an interesting idea. Has anyone used this in their design or come across it?


  • Options
    #77
    BarneyMc
    Registered Users Posts: 1,504 ✭✭✭BarneyMc


    Not bumping this thread by any means but a lot of interesting points have been raised concerning the 'sweet spot' for 'near passive' houses. I posted a thread some time ago and would like to know if the general design/form of the house is ok. It is to face west and this is more or less constrained due to the site layout. The south side has lots of glazing which is good. My only concern is that the rear projection does not fit in well with the compact design principle. Plans, etc. are here. Thanks.


  • Options
    #78
    BryanF
    Moderators, Home & Garden Moderators Posts: 10,140 Mod ✭✭✭✭BryanF


    BarneyMc wrote: »
    Not bumping this thread by any means but a lot of interesting points have been raised concerning the 'sweet spot' for 'near passive' houses. I posted a thread some time ago and would like to know if the general design/form of the house is ok. It is to face west and this is more or less constrained due to the site layout. The south side has lots of glazing which is good. My only concern is that the rear projection does not fit in well with the compact design principle. Plans, etc. are here. Thanks.
    answered on other thread


  • Options
    #79
    Eoghan Barra
    Closed Accounts Posts: 286 ✭✭Eoghan Barra


    Eoghan Barra wrote: »
    I'm using 200mm of rockwool fullfill, which costs about €7/m2, as opposed to about €100/m2 for external insulation, for example.

    Sorry folks, made a mistake. That should be €14/m2, not €7/m2.


  • Options
    #80
    Certified
    Registered Users Posts: 146 ✭✭Certified


    Hello Ireland!

    <snip>

    Happy building :)
    Certified

    Moderator: Please don't preach at posters here and read the forum charter before posting again.


  • Options
    #81
    just do it
    Registered Users Posts: 5,422 ✭✭✭just do it


    Certified wrote: »
    Hello Ireland!

    <snip>

    Happy building :)
    Certified

    Welcome to boards!

    What's your line of business? Passive house design? ;)


  • Advertisement
  • Options
    #82
    Certified
    Registered Users Posts: 146 ✭✭Certified


    Hi just do it,

    Thanks, yes I am involved in the design and build of Passive buildings. I've been lucky enough to have been involved with many different projects through the years, Passive, nearly passive and no where near Passive. looking back now, Im the first to put my hand up to admit that I have made mistakes in the past but in fairness the knowledge and products that exist today just were not around 5 years ago or maybe even 2 years ago.

    It really isnt that difficult or expensive to build to the Passive standard today.

    Anyway I felt I should say my little bit as I do have some experience under my belt in building in Ireland.

    Regards,

    Certified


Advertisement