Green Building Forum - In the long run high tech building solutions have no future Mon, 17 Aug 2026 02:32:12 +0100 https://www.greenbuildingforum.co.uk/newforum/ Lussumo Vanilla 1.0.3 In the long run high tech building solutions have no future https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1201&Focus=13947#Comment_13947 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1201&Focus=13947#Comment_13947 Tue, 05 Feb 2008 16:57:10 +0000 Chris Wardle In the long run high tech building solutions have no future https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1201&Focus=13948#Comment_13948 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1201&Focus=13948#Comment_13948 Tue, 05 Feb 2008 17:13:55 +0000 tony
The wind catcher things are in my opinion very wasteful of energy, too much hot air goes up them in more than one way.]]> In the long run high tech building solutions have no future https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1201&Focus=13953#Comment_13953 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1201&Focus=13953#Comment_13953 Tue, 05 Feb 2008 18:32:26 +0000 PaulT
A cave is a natural home, everthing else is man made and hence there are compromises to make.

For those who say we have mild climate - try telling the huge number of elderly people who are losing their thermoregulatory ability or spend some time outside without your high tec fleeces'.

I do not care about those of us who can afford to build deep green homes (I work with straw bale builders for example and would happily live in one). I am more concerned with the vunerable, inner city poor who should have as a basic right decent homes that are easy to keep warm and have decent air quality.

HRV is not just about energy efficiency - it delivers reliable and consistent air quality with the added benefit of pollen filtration (etc) for those who need it (the near 50% of the population with allergies, including 1 in 7 children with allergic childhood asthma, many with grass pollen allergies). HRV systems have been proven to aleviate the sysmptoms of asthma sufferers (UNI Strathclyde, CEDAR centre)

Without mechanical intervention (complete or in support of a passive stack) then this relaibility is not easily achivable. Highly designed individual homes may be finely tuned, but the majority will not.

A good example is the fact (BRE 2006) that homes with trickle ventilation (ie wind and passive stack driven) with an average air leakage of n50=13 failed to achieve the required ventilation rates in 68% of homes tested (by accurate tracer gas analysis).

Of all ventilation options only HRV is fully designed for specific air flow rates to individual rooms (please correct if you know otherwise). Because it suffers little heat loss the ventilation rate is not constrained by this factor - meaning that HRV systems are designed for air quality.

Parisitic energy usage (fans) are an issue but even in the UK climate (say 1500 degree days) most systems will return a COP fo over 3 (Gas heating). Future generations of fans (later this year) are going to be so efficent this will not be an issue.

Supply air windows are an interesting concept, but there are still outstanding questions - such as what happens in summer and how do you match the optimum air flow rate (assuming you can control it) with the required ventilation rate?

If your supply air window is next to a road you will get pollution and nios directly. HRV systems should take air from a high level.

HRV system life - I recently inspected and repairs an 18 year old system that had only had filter replacements as its annual maintenence. Dusts were clear and clean and the home owner reported they had the only home in the estate without condesnation problems (apart from many people running de-humidifiers).

Air quality sensors - some HRV's have these built in (humidity and also CO2 etc, if required). This allows them to respond to occupancy. Part F does allow for demand control ventilation systems, based on air quality sensors. I do not know of any home designed this way but I do plan on doing it for my own home (Very low trickle rate with continuous air quality sensors).

-------------------------------
In defence of british builders - if we pay them enough and train them enough they will do the job - do not confuse them with developers; It is the exploitative nature of building in the UK that has ingrained bad attitutes in many builders.

The only way we will improve the situation it to regulate both the installation (improved building regulations and many more inspectors) and insist on maintenence regimes to be incorporated into the Home Information Packs...]]> In the long run high tech building solutions have no future https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1201&Focus=13958#Comment_13958 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1201&Focus=13958#Comment_13958 Tue, 05 Feb 2008 18:50:33 +0000 Mark Siddall
Domlux www.domus.fi (window u-value 1.1, CP u-value 0.9)
Tiivi www.tiivi.fi (CP u-value 0.6)

Seasonally adjusted effective u-values that account for net-solar gain are about 0.6W/m2K on a window with a CP of about 1.6W/m2K. By using positive pressure in the early/late summer exhaust air windows can reduce cooling loads.
All the above taken from Low Energy Buildings and District Energy Systems, by L.D.D. Harvey.

If using fans to assist air movement then this parasitic energy use should be considered.
Whether this gain from supply air windows with MEV is greater than triple glazing and MVHR would require closer examination, personally I have my doubts but have not reached any real conclusion.

Mark]]> In the long run high tech building solutions have no future https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1201&Focus=13979#Comment_13979 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1201&Focus=13979#Comment_13979 Tue, 05 Feb 2008 21:52:57 +0000 biffvernon http://www.biffvernon.freeserve.co.uk/air_flow_windows.htm]]> In the long run high tech building solutions have no future https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1201&Focus=13980#Comment_13980 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1201&Focus=13980#Comment_13980 Tue, 05 Feb 2008 22:09:18 +0000 Paul in Montreal Posted By: biffvernonIf using fans to assist air movement then this parasitic energy use should be considered.

True, but this is just another component of incidental thermal gains as all the energy "wasted" in the fans ends up as heat in the building - which may be a negative if you need cooling admittedly.

Paul in Montreal.]]> In the long run high tech building solutions have no future https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1201&Focus=13996#Comment_13996 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1201&Focus=13996#Comment_13996 Wed, 06 Feb 2008 07:11:00 +0000 Mark Brinkley
No what worries me is that if MV is rolled out on an industrial scale, it won't be looked after, it will break down, no one will repair it, it will be turned of in summer and never put back on in winter. In the worst cases, the units will be sabotaged or nicked and sold on. The airtight house model depends on there being a fully functioning MV system in place. What happens when it breaks down?]]> In the long run high tech building solutions have no future https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1201&Focus=14002#Comment_14002 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1201&Focus=14002#Comment_14002 Wed, 06 Feb 2008 09:21:07 +0000 Peter Clark
I am impressed by the whole process they have gone through - theoretical studies, practical research, including objective data and canvassing users opinions, all published. It remains to be seen what it means in practice, as Tuna has said it is very difficult to know what to do as a private house holder trying to be green.

I am at a loss to know what to say to the constant mantra of 'what happens in the summer' except ... open the window!

As far as matching flow rates with required, I think we have to accept that sometimes it will not be optimal, is that a problem? I think it depends on what happens in practice, if it is sub-optimal most of the time, probably that is no good, if once a month for a few hours, probably that is OK. I feel that the attempt to have perfectly optimal living conditions, re ventilation, or anything else, is the cause of our environmental problems. To solve our problems we need to make compromises, that may mean having a draughty house, or too much humidity, occasionally.

If I had such a system installed, I would like to have one (small?) fan somewhere in case it proved necessary, but the aim would be not to use it, the noise is the problem for me. How about it PaulT, that would require some input from a ventilation engineer.

Peter]]> In the long run high tech building solutions have no future https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1201&Focus=14011#Comment_14011 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1201&Focus=14011#Comment_14011 Wed, 06 Feb 2008 10:53:29 +0000 Paul in Montreal Posted By: Mark BrinkleyNo what worries me is that if MV is rolled out on an industrial scale, it won't be looked after, it will break down, no one will repair it, it will be turned of in summer and never put back on in winter. In the worst cases, the units will be sabotaged or nicked and sold on.

Tackling your last point first about the units being "nicked or sold on". Are you serious? What would the market me for such units if, in your pessimistic view, people aren't using them? There are no valuable parts contained within (no copper for example). If you think that's a problem in the UK, then the UK has some fundamental issues beyond fossil fuel poverty.

As for the turning off in the summer and never being turned on, this is easily solved by linking the MHRV to the heating system. Ours is controlled by a humidistat but is essentially "on" year round. We don't even touch the controls, though have set the humidistat such that we increased winter humidity levels since dryness is a problem in a cold climate. In the summer it doesn't matter if it runs or not since, gasp, the windows are sometimes open on those days when it's cool enough to open them - of which there are a lot in the UK.

As for the repair, it's no different than servicing a heating appliance. Some people won't do it and there's nothing you can do about that - after all, people still die of CO poisoning. As I've mentioned already, maintenance is trivially simple.

Finally, for flow rates, they're not critical. Balanced is best, of course, but as long as there isn't serious depressurization then there's really no problem. I'll leave it as an exercise for the reader to figure out why depressurization is more important than over pressurization.

Paul in Montreal.]]> In the long run high tech building solutions have no future https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1201&Focus=14012#Comment_14012 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1201&Focus=14012#Comment_14012 Wed, 06 Feb 2008 11:55:17 +0000 Mark Brinkley
If they become mandatory in all new homes, then there will be a healthy resale market for the units, in order to get a new building finalled. Rather like what used to happen with the automatic door closers needed to get the fire rating and removed once the building inspector had issued the completion notice.

As for the repair issue, it's rather different to heating appliances which leave you freezing if they pack up. If your MVHR system doesn't work you might well not notice. Which could lead to a long term IAQ problems. Having got airtightness down to (for the UK) unimaginable levels, what happens next when the ventilation system goes on the blink?]]> In the long run high tech building solutions have no future https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1201&Focus=14013#Comment_14013 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1201&Focus=14013#Comment_14013 Wed, 06 Feb 2008 12:23:26 +0000 Paul in Montreal Posted By: Mark BrinkleyIf they become mandatory in all new homes, then there will be a healthy resale market for the units, in order to get a new building finalled. Rather like what used to happen with the automatic door closers needed to get the fire rating and removed once the building inspector had issued the completion notice.

Mark,

if you gave this a moment's thought you'd realize how ridiculous your assertion is. Have you ever seen a HRV? Any idea how it's installed? It is installed either in the basement (over here where we have basements) or, more likely in the UK, in the attic. It is not something small and visible like a door closer that can easily be removed. The cost of an HRV is pretty small too - equivalent, say, to a window. I fail to see how there could be a resale market since you're also implying that people in the UK wouldn't want them anyway. It is not something that is trivial to retrofit so I really can't understand what this mythical resale market is.

Your whole tone suggests that people in the UK are too stupid to operate and maintain such devices. I'm sure similar statements were made about central heating systems 40 years go. People in Canada are no brighter than people in the UK but I've never heard anyone here suggest not installing a HRV because it might be difficult to maintain or operate. They are very simple devices with little to go wrong. Even if one failed and wasn't noticed for several weeks, there is little chance of damage. Regularly scheduled maintenance at the start of the heating season is all that's required. This is true of all gas boilers anyway - it would be trivial to do both at the same time.

Are you suggesting it's better in the UK not to even try to "build tight, ventilate right"? Remember when smoke detectors were first installed? There were many public awareness campaigns of the need to change the batteries annually. Education is the key (both for the architects and builders in the first place and the end users). Your tone just sounds like defeatism. People like you are key to the education process - I think you should step up to the plate rather than down.

Paul in Montreal.]]> In the long run high tech building solutions have no future https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1201&Focus=14021#Comment_14021 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1201&Focus=14021#Comment_14021 Wed, 06 Feb 2008 13:42:52 +0000 Mark Brinkley
Smoke detectors are a good example. They are simple and easily maintained, but you'd be surprised just how many aren't.]]> In the long run high tech building solutions have no future https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1201&Focus=14022#Comment_14022 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1201&Focus=14022#Comment_14022 Wed, 06 Feb 2008 13:52:18 +0000 Chris Wardle In the long run high tech building solutions have no future https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1201&Focus=14023#Comment_14023 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1201&Focus=14023#Comment_14023 Wed, 06 Feb 2008 14:14:31 +0000 Peter Clark Posted By: Chris WardleCan temporary sub-optimal levels of ventilation be mitigated through the use of naturally hygroscopic materials like un-fired earth and untreated timber? Internal air quality can also be improved by plants.

Hi Chris,
This is the sort of way I am thinking, in my rather amateurish way. It seems from the results Dwell-Vent published, that in parts of the UK, in some situations, this system can work very satisfactorily most of the time. Less initial cost, no electricity costs for running it, almost no maintenance - no fan noise!
I think this is a very attractive and promising result, and it behoves us to find ways of tweaking the system to optimise the periods of less than perfect operation, mostly due to weather conditions.

This is why I am also attracted to hygroscopic, breathing walls.]]> In the long run high tech building solutions have no future https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1201&Focus=14025#Comment_14025 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1201&Focus=14025#Comment_14025 Wed, 06 Feb 2008 14:53:39 +0000 tony
Natural materials can buffer moisture in the internal air and some breathing walls can remove it and send it outside but in moderation ( not when there are problems)

Plants are nice inside buildings but so is fresh air

I cannot understand our resistance to MHRV it is like breathing fresh out door air all the time but at indoor temperatures]]> In the long run high tech building solutions have no future https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1201&Focus=14027#Comment_14027 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1201&Focus=14027#Comment_14027 Wed, 06 Feb 2008 15:27:39 +0000 PaulT
Using a whole house ventilation system (with passive stack assistance if possible) would provide a consistent air flow through the windows. In addition the flow rate could be adjusted to respond to climatic conditions (such as the difference between daytime and nigthtime solar gain and air temperature. The fans could also be set up to reverse tha air flow, as required... a lot of detailed modeling and in-situ testing is going to be needed (particularly regarding analysing how distinct rooms operate. As alway minimum ventilation rates are required fro occupation.

There are concerns over HRV noise. Most quality systems are pretty much inaudable on trickle settings and a whole lot quiter than standard extract fans. In addition trickle vents are not used, greatly reducing exterior noise. If noise is present it would most likely be duct noise from poor quality flexible ductin or undersized ducts resulting in high air speeds.

The largest market for HRV's, by far, will be from housing associations as they struggle to meet CSH level 3 (SAP -25%). This is because of the typical 40% contribution to heat loss by ventilation. Housing associations will, as Landlords have duty of care to maintain systems (annual inspection and filter replacement, at the same time as servicing the gas boiler and carbon monoxide sensor,smoke detectors, etc; CORGI plumbers are now being trained in HRV systems!).

Those who buy homes with HRV systems will have a Home Information Pack that should state annual maintenence (or more) is required.If they chose not to then the HIP inspector/valuer should report on the fact and indicate a problem with the home and subsequent valuation.

The people and systems are being put in place to manage our homes... just need to build decent ones!]]> In the long run high tech building solutions have no future https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1201&Focus=14028#Comment_14028 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1201&Focus=14028#Comment_14028 Wed, 06 Feb 2008 15:36:28 +0000 tony In the long run high tech building solutions have no future https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1201&Focus=14030#Comment_14030 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1201&Focus=14030#Comment_14030 Wed, 06 Feb 2008 16:23:26 +0000 Peter Clark Posted By: PaulTa lot of detailed modeling and in-situ testing is going to be needed

I understood that this has already been done and that Dwell-Vent have a database of the necessary numbers, that permits systems to be designed correctly, but I don't know the details. I think that's what they are trying to convince BRE about.

Can anyone help with the block quotes?]]> In the long run high tech building solutions have no future https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1201&Focus=14031#Comment_14031 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1201&Focus=14031#Comment_14031 Wed, 06 Feb 2008 16:29:14 +0000 Paul in Montreal
Paul.
p.s. you can go back and edit your posts and then select that button and it will fix everything up]]> In the long run high tech building solutions have no future https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1201&Focus=14032#Comment_14032 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1201&Focus=14032#Comment_14032 Wed, 06 Feb 2008 16:31:32 +0000 Peter Clark Posted By: Paul in MontrealFor block quotes, you should select the "html" button in the "format comments as ..." section below.

Paul.
p.s. you can go back and edit your posts and then select that button and it will fix everything up

many thanks]]> In the long run high tech building solutions have no future https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1201&Focus=14036#Comment_14036 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1201&Focus=14036#Comment_14036 Wed, 06 Feb 2008 17:13:17 +0000 Bowman In the long run high tech building solutions have no future https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1201&Focus=14043#Comment_14043 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1201&Focus=14043#Comment_14043 Wed, 06 Feb 2008 18:13:42 +0000 Mark Siddall From a PH perspective is that it is essential for space heating thus you can't fail to turn it on if you want the home to be heated. From my perspective this is both simple and effective. MVHR in houses with central heating is where you have to many systems that can be subject to greater risk of failure, perhaps this is where Paul in Montreal's humidistat approach comes into play (not my prefered optin but usbale non the less.)

Mark]]> In the long run high tech building solutions have no future https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1201&Focus=14046#Comment_14046 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1201&Focus=14046#Comment_14046 Wed, 06 Feb 2008 19:25:29 +0000 Mark Brinkley
I assume you are referring to the systems where they add an electric post-heater onto the incoming ducting, in effect a warm air heating system. That was what I witnessed in Hanover during the BRE's PassivHaus study tour this time last year. I guess in that situation you would have a useful failsafe to ensure that the MVHR unit was serviced. But is PH so prescriptive that you have to heat in such a way? Is this indeed the future?]]> In the long run high tech building solutions have no future https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1201&Focus=14047#Comment_14047 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1201&Focus=14047#Comment_14047 Wed, 06 Feb 2008 20:21:20 +0000 Paul in Montreal heating system is not passive is it? It's just a low energy house. An airtight house needs active ventilation no matter if it's heated or not. I under stand, though, that small capacity ASHPs are often used in conjunction with MHRV in these so-called "passive" houses since this is much more efficient than straight electric resistance heating. Since the heat load is low, the MHRV has sufficient airflow to distribute the small amount of heat required. But, just to be clear, a MHRV is not, in general, a heating system - it is a ventilation air distribution system which is always required , irregardless of any other heating system fitted (or not).

The reason we have a humidistat is so that the MHRV can be "turned down" somewhat in winter to prevent excessive dryness as we have the opposite problem compared to the UK. The MHRV also has manual override switches in all the bathrooms to turn it onto full speed for 20 minutes whilst having a shower etc.

Paul in Montreal.]]> In the long run high tech building solutions have no future https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1201&Focus=14067#Comment_14067 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1201&Focus=14067#Comment_14067 Thu, 07 Feb 2008 00:17:24 +0000 Mark Siddall PH is not so prescriptive per-se but for the most economic solution this is the ideal. Elec resistance heating was used in one PH when I went on the BRE PH tour (no. 2). The rest albeit larger schemes used wood pellets and district heating. Gas, with hydronic feed to post-heater distribution, and compact heating units (incorporating heat pumps and MVHR) are the best low carbon option that I'm aware of. Is it the future; it is one possible future.

Mark]]> In the long run high tech building solutions have no future https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1201&Focus=14069#Comment_14069 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1201&Focus=14069#Comment_14069 Thu, 07 Feb 2008 07:14:02 +0000 biffvernon Posted By: Peter Clark
Posted By: PaulTa lot of detailed modeling and in-situ testing is going to be needed


I understood that this has already been done and that Dwell-Vent have a database of the necessary numbers, that permits systems to be designed correctly, but I don't know the details. I think that's what they are trying to convince BRE about.

Can anyone helpI'm just waiting for someone willing to pay me to make one :)]]> In the long run high tech building solutions have no future https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1201&Focus=14074#Comment_14074 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1201&Focus=14074#Comment_14074 Thu, 07 Feb 2008 10:31:59 +0000 PaulT
Biff - sorry I have spec'd French Oak windows with shuters (as complete units) - These will perform better than triple glazing. the shutters will be mechanic, yet another system(!), but will allow me to use the central controller to adjust solar gain and heat losses automaticaly (OK, not practical for most, but I am developing a luxury version of an ECO home as a demonstration of what can be done).

I think the most important point to make is that PassivHaus does not mean Passive House!

The German is a proven engineering solution. They have built a proven conceptual model that works, although it is not problem free and may need adjusting for the UK climate. the ventilation rate is a good example, in Germany they use a lower ventilation rate as the Climate is much drier in winter; This is also the case in Canada where the the rate is 0.4 ach (?). (UK 0.5)

When considering ventilation though, a word of warning - we have just about the smallest homes in the 'Western developed world' (new builds around 70m2, 1920 UK 100m2 +, progress?). This means that the air resevoir is smaller and, combined with a humid climate there is greater risk of air quality problems.

Heating - the electric air heater is more amatter of convenience and cost; If you already have a distribution system why bother? Well, you lose the ability to heat zones to different temperatures, so if the bathroom is 'cold' (consider thermal comfort when getting out of the shower) the whole house gets heated to a higher temperature. This is a good example of diminishing returns - in super insulated home the thermostat gets turned up.

My approach will still be to fit an underfloor perimeter heating loop and wire up bathrooms, etc; cheap(er) to do now than regret it later.]]> In the long run high tech building solutions have no future https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1201&Focus=14077#Comment_14077 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1201&Focus=14077#Comment_14077 Thu, 07 Feb 2008 11:18:19 +0000 Chris Wardle
Whilst I don't want to sit shivering at 5degreesC in the winter, I like different parts of the house being at different temperatures and for the internal temperature to track the outside temperature to a certain extent. How can you appreciate warmth unless you experience cold? I want a wood stove in my living room because it lifts my spirits on cold winter evenings as well as keeping me warm.

Are individual personal preferences and aspirations legitimate reasons for adopting solutions that might be considered sub-optimal from an energy efficiency point of view?]]> In the long run high tech building solutions have no future https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1201&Focus=14079#Comment_14079 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1201&Focus=14079#Comment_14079 Thu, 07 Feb 2008 12:51:01 +0000 Peter Clark Posted By: Chris WardleAre individual personal preferences and aspirations legitimate reasons for adopting solutions that might be considered sub-optimal from an energy efficiency point of view?

Certainly if they are NOT sub optimal from an energy efficiency point of view!

But even if they are?]]> In the long run high tech building solutions have no future https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1201&Focus=14080#Comment_14080 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=1201&Focus=14080#Comment_14080 Thu, 07 Feb 2008 12:59:43 +0000 Paul in Montreal Posted By: PaulTBowman - good point about sea air; We use electrostatic pre-filters which should help. Also the plastic cores should not corrode and are washable, salt being disolvable. We are installing a system in Filey and will ask if we can monitor the situation.

Electrostatic filters are metal and so would be subject to corrosion. My understanding is that such filters are deprecated for several reasons: they only work when clean (which doesn't last long), they greatly increase static pressure in the duct system and they can generate ozone. 100mm thick pleated filters of MERV10 are a much better bet - they only need to be changed annually, they have have a much lower static pressure impact, they don't generate ozone and require less user intervention than electrostatic systems. You're right about the plastic core not being corrodible though.

Posted By: PaulTThis is also the case in Canada where the the rate is 0.4 ach (?). (UK 0.5)


The actual rate is determined by the number of occupants and is measure in litres per second. Following our post-renovation blower door test, we came in at 0.35ACH, but the calculation for the recommended ventilation rate based on the occupancy load was closer to 0.27ACH (both at normal pressure).

Posted By: PaulTWhen considering ventilation though, a word of warning - we have just about the smallest homes in the 'Western developed world' (new builds around 70m2, 1920 UK 100m2 +, progress?). This means that the air resevoir is smaller and, combined with a humid climate there is greater risk of air quality problems.


This is a very good point which is why proper design of the ventilation system is important (and part of the reason fully passive systems are almost never adequate).

Paul in Montreal.]]>