Passive (or near) House Plans - Comments Please

BryanF

BarneyMc wrote: »

Hi Do-more. No, my architect said he will do the PHPP after the plans have gone through the planning process. Should he be doing it before it goes through the planning process do you think?

ask yourself how do you tweak or change things after you've got planning? what the PHPP is advocating is a slightly more front loaded design process, than we are accustomed to in Ireland. what this allows for, is a more thought-out house design before it is fixed by the LA planning permission.

Do-more

BarneyMc wrote: »

Hi Do-more. No, my architect said he will do the PHPP after the plans have gone through the planning process. Should he be doing it before it goes through the planning process do you think?

As Bryan has said you really need to do the PHPP before the planning application is made otherwise you lose a lot of the opportunity to improve your house's performance.

Take for example this question you have regarding the orientation of the house, waiting until planning is complete is too late to decide on that, but running a PHPP now will give you clear answers as to what effect such changes will cause.

Your Architect is probably concerned that if planning is rejected outright then the money spent on the PHPP will have been wasted but if he waits until after planning has been granted he is wasting a big part of the chance of improving your house's performance.

Speaking of my own experience we arrived at a design that I was happy to go to planning with and then ran the PHPP and adopted a number of changes as a result so I now know that if I get planning (fingers crossed, I should know the result in two weeks time) I will not be able to go direct to tender without any changes or worry about whether I will have to seek retention etc.

BarneyMc

Do-more wrote: »

Your Architect is probably concerned that if planning is rejected outright then the money spent on the PHPP will have been wasted but if he waits until after planning has been granted he is wasting a big part of the chance of improving your house's performance.

Yes I think you've hit the nail on the head here. Thanks BryanF and Do-more for this advice, I'll use it!

BryanF

taken from http://www.boards.ie/vbulletin/showthread.php?p=76772646#post76772646 where Barney referred to this thread and asked:

BarneyMc wrote: »

My only concern is that the rear projection does not fit in well with the compact design principle. Plans, etc. are here. Thanks.

its been two months since we discussed this,

1. have you had a pre-planning to fix the design and get an understanding from the planners that it does not need to change? (I appreciate they rarely give applicants with that confidence)
2. also have you run the phpp as this is what you need to do to answer your question.

I'm currently designing a non-standard non-south facing house and intend it balance the phpp (& house spec etc) to suit my design (site, layout,client requirements, orientation etc) as opposed to designing the house to suit phpp.. if you get my meaning.. hope this helps

Eoghan Barra

sas wrote: »

In the interests of fully informed decisions, certified PH entrance doors cost in and around €5000.

Sas, how does that compare to non-certified PH entrance doors in price terms?

BarneyMc

BryanF wrote: »

taken from http://www.boards.ie/vbulletin/showthread.php?p=76772646#post76772646 where Barney referred to this thread and asked:
its been two months since we discussed this,

1. have you had a pre-planning to fix the design and get an understanding from the planners that it does not need to change? (I appreciate they rarely give applicants with that confidence

Yes met with the planners and they're perfectly ok with the layout as is.

BryanF wrote: »

also have you run the phpp as this is what you need to do to answer your question.

No, perhaps I should now that the planners are ok with it. I'll ask my architect to do this. Cheers!

BarneyMc

I've also recently considered removing the office on the ground floor (think I'll just set up a work area in the room at the back of the ground floor), brining the utility to the front of the house and incorporating the WC and back hall into the main body of the house (where the old utility used to be).

This would mean not having to build an "annex" for the WC and back hall which I'd imagine would be a bit messy to build (wide cavity construction)???

sas

Eoghan Barra wrote: »

Sas, how does that compare to non-certified PH entrance doors in price terms?

Doors for a PH (certified or not) are outrageously expensive for some unknown reason. You'd still be in the 3500 region from my pricing last year.

The only difference between the doors and an equivalent sized window is the threshold, yet for some reason they charge so much more for them.

BarneyMc

sas wrote: »

Doors for a PH (certified or not) are outrageously expensive for some unknown reason. You'd still be in the 3500 region from my pricing last year.

The only difference between the doors and an equivalent sized window is the threshold, yet for some reason they charge so much more for them.

Perhaps a porch (outside the building envelope) with 2 non PH doors would be a more cost effective alternative? Then again there's the porch building costs including the extra door.

sas

BarneyMc wrote: »

Perhaps a porch (outside the building envelope) with 2 non PH doors would be a more cost effective alternative? Then again there's the porch building costs including the extra door.

Don't know enough to comment. In my case I have a porch but the inner door is passive spec anyway.

Eoghan Barra

sas wrote: »

Doors for a PH (certified or not) are outrageously expensive for some unknown reason. You'd still be in the 3500 region from my pricing last year.

The only difference between the doors and an equivalent sized window is the threshold, yet for some reason they charge so much more for them.

Thanks for that, sas. Swindlers the lot of them. May have to consider sub-passive spec. doors so.

BarneyMc

BryanF wrote: »

taken from http://www.boards.ie/vbulletin/showthread.php?p=76772646#post76772646 where Barney referred to this thread and asked:
its been two months since we discussed this,

1. have you had a pre-planning to fix the design and get an understanding from the planners that it does not need to change? (I appreciate they rarely give applicants with that confidence)
2. also have you run the phpp as this is what you need to do to answer your question.

I'm currently designing a non-standard non-south facing house and intend it balance the phpp (& house spec etc) to suit my design (site, layout,client requirements, orientation etc) as opposed to designing the house to suit phpp.. if you get my meaning.. hope this helps

Based on my plans just how much much should a PHPP cost? I'm beginning to see my expenses soar without even an application to the planners! Will the PHPP pay for itself or would a DEAP do? I'll be building wide cavity and am thinking maybe the cost of the PHPP I've been quoted would be better spent on the actual build itself. Confused.com

BryanF

BarneyMc wrote: »

Based on my plans just how much much should a PHPP cost? I'm beginning to see my expenses soar without even an application to the planners! Will the PHPP pay for itself or would a DEAP do? I'll be building wide cavity and am thinking maybe the cost of the PHPP I've been quoted would be better spent on the actual build itself. Confused.com

measure twice, cut once
if nothing else help you decide the best glazing to use, which should save you the cost of the process. see recent thread by FClauson

sinnerboy

BarneyMc wrote: »

Based on my plans just how much much should a PHPP cost? I'm beginning to see my expenses soar without even an application to the planners! Will the PHPP pay for itself or would a DEAP do? I'll be building wide cavity and am thinking maybe the cost of the PHPP I've been quoted would be better spent on the actual build itself. Confused.com

It takes me the best part of a working week to prepare A PHPP. Maybe some others have picked up more work at this and are therefore more proficient. So I reckon a fee of between Eu750-1000 would be about right.

BarneyMc wrote: »

Getting my site plans drawn up now. My architect is proposing to tilt the house just 10 degrees north of due west. This means that the glazed south side will be tilted 10 degrees to the west.

There is no major reason for this other than the fact that it will face directly into the corner of the field. From an energy performance position will this make much difference rather than keeping the south side facing direct south (plan images attached at start of thread)?

If you feel you need a measured answer to these kind of questions - you need a PHPP analysis. Once done - it is relatively simple to ask many many "what if" questions like this.

BarneyMc

sinnerboy wrote: »

It takes me the best part of a working week to prepare A PHPP. Maybe some others have picked up more work at this and are therefore more proficient. So I reckon a fee of between Eu750-1000 would be about right.

Eu750-1000 seems like a good week's pay in these times! I should have been an architect!

sinnerboy wrote: »

If you feel you need a measured answer to these kind of questions - you need a PHPP analysis. Once done - it is relatively simple to ask many many "what if" questions like this.

Yes good point. I guess these are the things I wanted to hear and not just have a pretty spreadsheet to stare at. Convinced, I'll go ahead with a PHPP.

Just one last question, should I/the architect be identifying these "what if's" now so when the PHPP is completed they can be answered by the PHPP? Rather than "now that we've got the PHPP" what shall we do with it?

Thanks for all the help with this guys!

sas

BarneyMc wrote: »

Eu750-1000 seems like a good week's pay in these times! I should have been an architect!

Less tax, less PI insurance and less on going training costs. We've all acknowledged that building a house has become a much more complicated affair. I'm sure the licenses for some of the software required are steep.

And for those that don't know me, no, I'm not an Architect.

beyondpassive

The PHPP analysis work should involve more than simply populating the spreadsheet to build a thermal performance model, it should inform a report. A poster here supply's this as part of the service. This report will be included in any tender and will highlight where the building is losing heat or gaining solar overheating, it should also act as guidance to any builder as to what level of workmanship is required for airtightness and continuity of insulation. the importance of incorporating the MHRV in the fabric design. Usually reports would also include visual thermal bridge analysis for eaves and footings and a performance specification for the window suppliers. many reports run to over twenty pages. The report can also size the heating system based on worst case weather data and give options in that area. For many projects it makes sense to design fro the inside out, design the heating system and then spec the fabric to optimise the performance of the heating system, be it gas/solar/thermal store/underfloor or Heat pump/thermal store/PV array.

Its easy to make changes to the building model and that's its genius, it can inform decisions, especially with regard to window selection. So agree with sinnerboy, its more than a weeks work and is the best money you can spend, even at twice the price, but then I would say that.

BarneyMc

sas wrote: »

Less tax, less PI insurance and less on going training costs. We've all acknowledged that building a house has become a much more complicated affair. I'm sure the licenses for some of the software required are steep.

And for those that don't know me, no, I'm not an Architect.

Fair points.

BarneyMc

beyondpassive wrote: »

The PHPP analysis work should involve more than simply populating the spreadsheet to build a thermal performance model, it should inform a report. A poster here supply's this as part of the service. This report will be included in any tender and will highlight where the building is losing heat or gaining solar overheating, it should also act as guidance to any builder as to what level of workmanship is required for airtightness and continuity of insulation. the importance of incorporating the MHRV in the fabric design. Usually reports would also include visual thermal bridge analysis for eaves and footings and a performance specification for the window suppliers. many reports run to over twenty pages. The report can also size the heating system based on worst case weather data and give options in that area. For many projects it makes sense to design fro the inside out, design the heating system and then spec the fabric to optimise the performance of the heating system, be it gas/solar/thermal store/underfloor or Heat pump/thermal store/PV array.

Its easy to make changes to the building model and that's its genius, it can inform decisions, especially with regard to window selection. So agree with sinnerboy, its more than a weeks work and is the best money you can spend, even at twice the price, but then I would say that.

Thanks for this, I'll request a similar report from my architect. Sounds like good value to me now!

sinnerboy

In fairness I should have stated PHPP + report as BP outlined in some detail there.

BarneyMc

I'm in a situation where I'm about to finalise plans but not sure where to place the wood burning stove. I'd like to place it somewhere in the kitchen/dining area that's central in the house (will have to be placed on an external wall also due to internal layout).

Does that mean I'll have to build a chimney where I want the stove OR have the flue climb up the wall on the outside? For the latter does the flue have to extend up to the ridge of the building and if so then how can it be supported? Perhaps a proper chimney is a better option but how will this affect air tightness?

The attached picture shows both options in one go!

BryanF

I don't understand the relevance of the picture, its seems to suggest that the existing chimney is redundant and a new flue is installed out side of it.. I may be wrong here of course:o

as regards air-tightness - if you look around the forum there are several threads regarding 'sealed stoves' / external air supply stoves. this approach is applied to remove issues of air-tightness and issues of draw from the MVHR etc. I've seen them in operation and they work grand

sas

BarneyMc wrote: »

I'm in a situation where I'm about to finalise plans but not sure where to place the wood burning stove. I'd like to place it somewhere in the kitchen/dining area that's central in the house (will have to be placed on an external wall also due to internal layout).

Does that mean I'll have to build a chimney where I want the stove OR have the flue climb up the wall on the outside? For the latter does the flue have to extend up to the ridge of the building and if so then how can it be supported? Perhaps a proper chimney is a better option but how will this affect air tightness?

The attached picture shows both options in one go!

The biggest reason to use a regular chimney versus a metal one is product life, the metal flue will definitely need replacing several times over the life time of a masonry chimney.

If we are talking about a cavity build, I would build a masonry chimney in the same manner as that in the picture. Basically, the chimney is part of the external leaf and fully visible from the outside i.e. the chimney stack is outside the insulated shell.

Then the stove would be connected to it via a flue which travels horizontally from the back of the stove, through the inner leaf, through the insulated cavity and finally connects into the chimney in the outer leaf.

The PHI recommends that chimneys\flues are outside the insulated shell of the house in the manner I've just described.

Hope I described it clearly.

SAS

BarneyMc

Thanks guys. Yes SAS you've hit the nail on the head... that's exactly what I wanted to know. A chimney I need then rather than a flue.

The only other thing I need to know then is how high it needs to go. It will be in a place just like in the image so will it have to continue up to the full height of the ridge of the house?

BryanF

BarneyMc wrote: »

Thanks guys. Yes SAS you've hit the nail on the head... that's exactly what I wanted to know. A chimney I need then rather than a flue.

The only other thing I need to know then is how high it needs to go. It will be in a place just like in the image so will it have to continue up to the full height of the ridge of the house?

see dia 1 in attached doc
http://www.environ.ie/en/Publications/DevelopmentandHousing/BuildingStandards/FileDownLoad,1650,en.pdf

sas

BarneyMc wrote: »

Thanks guys. Yes SAS you've hit the nail on the head... that's exactly what I wanted to know. A chimney I need then rather than a flue.

The only other thing I need to know then is how high it needs to go. It will be in a place just like in the image so will it have to continue up to the full height of the ridge of the house?

Something I forgot to mention earlier.

I believe that once you get underway you would do well to consider one of the chimney systems. The most common one here has a specific block with the socket to receive the horizontal pipe into it. The system also has access doors on the outside of the chimney to allow access for sweeping.

If I was doing this again I'd seriously consider one of these.

BarneyMc

Saw this today in one of the papers. Thought it looked good as a buffer area and might suit my plans (south elevation). Has anyone built one of these 'buffer areas' or think they might be useful? I believe they are constructed outside the building envelope?

Should say that there are sliding doors on the main building wall so it can be shut off in cold weather and at night, etc.

BryanF

BarneyMc wrote: »

Saw this today in one of the papers. Thought it looked good as a buffer area and might suit my plans (south elevation). Has anyone built one of these 'buffer areas' or think they might be useful? I believe they are constructed outside the building envelope?

Should say that there are sliding doors on the main building wall so it can be shut off in cold weather and at night, etc.

I very found of this approach , i've seen this used outside of the thermal envolpe as you suggest - their usefulness imo depend alot on whether they will be a usable space.
the winter-garden/sun-room requirement has changed as the cost of glazing and our ability to have more constant internal temps with MVHR/ good air-tightness as standard (there are still some crazy people out there who build traditional conservatories and then place radiators in them!!). The design you suggest does require some consideration in the passive house modelling, but this may come down to how its described in the calculation. Depending on the situation, careful consideration is necessary to give thermal separation, thermal mass, shading and risk of overheating (or cooling).

just do it

BarneyMc wrote: »

Saw this today in one of the papers. Thought it looked good as a buffer area and might suit my plans (south elevation). Has anyone built one of these 'buffer areas' or think they might be useful? I believe they are constructed outside the building envelope?

Should say that there are sliding doors on the main building wall so it can be shut off in cold weather and at night, etc.

All depends on budget! I'd say if you like it submit the plans with it, model your house up in PHPP with and without it. Build it, or alternatively without it and in such a way that you can add it on in the future should funds allow. Anyway food for thought;)

BarneyMc

Finalising plans this weekend and having second thoughts about some of the south facing floor to ceiling windows. I know they give a great view to the outside but are there any installation issues regarding airtightness (where they meet the floor)? If so then would they be better sitting a block or 2 off the ground?