Doing an extensive renovation to an old house to try and achieve air tightness and insulation levels towards the passiv house standard, what monitoring do you think should be done. I presume my house is at the bottom end of the scale. It is often windy inside!

Should I get some kind of energy assessment now and on completion to see the difference or is it just a waste of money? I will be removing chimneys etc and so I suppose they are not included in air change tests otherwise you would need a very big fan. If they are not then surely that simple measure will not be recorded as a gain!

I know there are passivhaus purists and that I will not likely reach the true standard but it is certainly something to aim towards. Are there particular things which are worth monitoring e.g thermal camera, air tightness etc. I presume air tightness testing at completion would both be an incentive for builders to do good work and also a useful way of fault-finding.

What are your thoughts? Would it be of interest if I documented progress?
Thanks
Paddy

Temperature monitoring you can do yourself with a few iButtons around the place, electrical stuff with a cheap monitor (I have one and it is very informative and can log to a PC). Weather conditions data should be easy enough to find for your area (not that I know where you are). Gas and water usage can be taken from the meters (you do have a water meter don't you). Pressure testing would have to be done by professionals. Air tightness is a bit problematic without MVHR (intend to fit it if I can't sell the place soon)
A large housing association down my way wanted to show that all the heat pumps they had fitted had reduced their carbon foot print, unfortunately they did not monitor until after they were fitted. No conclusions could be drawn.
Have been working on insulation and airtightness on my house I can say that it certainly seems to make a difference, shall know when this winters bills are in. I have also been working on 'behavioural change' with my lodger. Hard work but it seems to be working (no more 40 minute showers for her, leaving windows open all day and night and saying "it's cold").

So yes, documenting everything is very useful. My best second and third best projects (can't use the term 'investment' really) were draught proofing the doors (£16) and insulation loft/cold water tank/hot water cylinder (£20, £70 if you include the breathable bags I made for it). Fourth was new glazing to replace the blown ones, managed to fit in 4-16-4 units into my existing timber frames (also made them open and close properly, whole lot, including scaffolding, paint, sealants £600).
House now uses between 28-30 kWh/day (washing days are the highest), yesterday was 22 kWh (decorating day).

Best investment was a washing line and some pegs (£2 and still being used 6 years on).