Are we talking about build costs of lifetime costs?

How meaningful will the answer be? It has been better to spend on insulation and to omit the heating system but culturally we dont do it.

It will always be more expensive in the short term to build well but it pays back big dividends if you have no or lower running costs.

Passivhaus could cost anywhere between nothing and 25% more depending who you ask.

True about the heating system - i couldn't imagine my house without the rads keeping me warm in the morning!

On PassivHaus, i have read about what the potential additional costings would be, but i have not found any evidence relating to how people have been able to come about with these figures. Of the understanding i have, there will probably not be too much info out there relating to the Gold standard.

The idea of the dissertation topic (at the end of the day) will be to produce some 'model' relating to the additional costings. Whether this turns out to be a simple formula that says 'Silver level = 'Original Build Cost + x%' etc... i don't know.

My theory behind the topic relates back to the code for sustainable homes, and how the differing levels of the AECB energy performance standards can be the equivilant of the CSH Star/Level ratings.

The definition is rather elusive, try http://www.aecb.net/forum/index.php?topic=602.0

Another point relating to build costs is one of house density per plot. As insulation levels are increased, so is the footprint of the building. For example, masonry walls up to 300mm thick require strip foundations of 600mm Likewise walls of 400mm thick require founds of 700mm and so on. Think also of the extra digging spoil, concrete etc. In an extreme case, this may mean say 9 houses being built on a site instead of 10. Cost in this scenario is related to less profit margin on the site. See AJ 09.02.06 for an article which touches on the increased costs relating to higher levels of insulation

I remember that journey myself. The main advice I would give regarding any Dissertation is to keep the subject narrow and the investigation deep. Best of luck with it.

Good point Tom

Yes James, I'm convinced this self-interest calculation, once it sinks in to middle England, will be by far away the biggest driver of low-energy renovation and newbuild (worldwide likewise - meaning cooling not heating in hot countries) - will render Bldg Regs, Kyoto etc almost irrelevant. Up to now, lo-energy measures have tried to justify themselves in payback from reduced fuel/running costs - but now capital value's coming in as well - the prospect of value rising increasingly ahead of the market on the one hand, versus value stagnating, dropping or even unsaleability at any price on the other hand - another negative equity crisis on the way! When it comes to buy/sell time (or to rental decision time) buyers will be calculating that this ordinary house will cost me £250,000 more to heat, over the next 10yrs, than that one, and will pitch their buy (or rent) offer accordingly.

Good for you Chris, stick to your guns

drjonnyc,

Silver: The Stamford Brook project is the close to the AECB Silver. Reports are that is cost 9% more to construct, though this cost does include for other aspects of the construction sustainable (airtightness cost <1% additional capital cost). www.lmu.ac.uk/as/cebe/projects/stamford/pdfs/del4const.pdf The principle cause of the additional cost seems to be the MVHR system, the associated ductwork and builders work. Once airtightness standards are updated to <5m3/m2 then MV is pretty much a requirement for indoor health (condensation and mould growth control) as a consequence the additional capital cost will reduce accordingly.

PassivHaus: The CEPHEUS report highlights that PH costs between 0-15% additional capital cost. Sadly there is no detailed cost break down. See www.passivehouse.com/07_eng/news/CEPHEUS_final_long.pdf Since the CEPHEUS report was published the cost of PH technologies has continued to fall rendering the additional cost at even less of a premium. The German/Austrian cost is generally reported to be <5% additional capital cost (PH Conference Proceedings 2007).

NOTE: At a national level central heating is a relatively "new" technology and market penetration has, all in all, been relatively slow since becoming available and affordable for the populous. Furthermore the fact that many of us are familiar with the technology does not mean that it is "appropriate" under all conditions. Ultimately central heating is merely a means of distributing heat.
The PH concept permits the required heat to be distributed by full fresh air and (the energy saving) MVHR system. This is achieved by directing the capital cost of the central heating system (rads, pipes, labour and a large proportion of the heating plant) into the envelope thus significant energy savings can be made at almost no additional capital cost compared to Silver standard. So how is the building heated? The heat losses from the PH are now low enough to permit an all-fresh-air-heating system supplying up to 8lts/person/sec at up to 50C; therefore satisfying a heat load of 10W/m2. It is on this basis I believe that there should be little or no additional capital capital cost increase between PH and Silver standard (though there may be additional costs for the QA, design work and some site management issues.)

Gold: The additional cost of renewables has to be factored in. You will note that the Gold standard required higher electrical energy efficiency. This is due to the fact that the cost per kWh saved is generally cheaper than the cost per kWh bought. When purchasing renewables you are effectively paying your energy bills up front and due to the cost premium of renewables it is better to invest in energy efficiency.

Other issues to consider are
1) The site constraints: A noisy site will receive planning conditions that will necessitate MV. Under this condition the additional capital costs are minimised.
2) Surface area to volume ratio: A block of apartment units will have a better ratio thus reducing heat losses per unit. The consequence is that the additional cost per m2 of each unit is less than say a detached house. Under these conditions terraced houses are also considered to be good economic option.

Hope this helps.
Mark

Yup. Are you at the same contractors?

Mark

Phone me.

Mark