Since then we have spent a lot of money on improving the property. The cavity walls we have were much disputed and one guy did put a camera into the wall and found a cavity but said they wouldn’t be happy to fill the cavity with insulating material because the cavity looked like it was bridging in places.

Anyway, we replaced all the windows recently (more about that in another post soon) and I can tell you that we definitely do have a cavity, albeit narrow, having seen it for myself when the old window frames were taken out. It looks like cavity insulation will not be possible however, based on their previous comments.

We have now insulated the roof space, which was a very tricky job. The roof timbers come down into the top of the external walls at floor level of the 1st floor, so the entire first floor is "in the eaves". The remaining 50% or so of the surface area of the ceiling space on the 1st floor was flat ceiling that could be easily insulated in the loft. Last winter these rooms were seriously cold - when it was sub 5C outside you could feel cold air pouring down on your face at night from the eaves, which lets face it was like living in a shed - the part of the room covered by the eaves consisted of circa 8mm plasterboard, an air gap of around 100mm about 1mm of felt, and about 10mm of concrete roof tile - with air circulating in there.

We didn’t want to pull the ceilings down to insulate, and taking the roof off was a major project. We only had 100mm or so void between the roof timbers, but luckily almost all of them had storage cupboards at the edges of the rooms. So what we did was get some brave masochists to climb into these tiny cupboards and push 50mm thick Celotex foil-backed phenolic insulation boards up towards the apex of the roof until they hit the perlins (timbers that run perpendicular to the roof timbers.

This was no mean feat, requiring measuring and cutting a great many slices of Celotex boarding and forcing them up one after another as they had to be a snug fit and the small cupboards did not allow full length pieces to be cut, so each pair of rafters needed three or more chunks of celotex cut to fit. We also had to cut a new opening into one of the stud walls in one room, to create a new cupboard on that side of the room so this process could be carried out on both sides of the room. Not such a bad thing given that we have gained a storage cupboard.

Finally in the loft void, which we had already discounted as storage space (if you’re going to put it in the loft… you probably don’t need it so freecycle it!), we laid 50mm Thermafleece batts between the rafters up to the exposed edges of the celotex boards that came up to the perlins, then dumped about 20cm Warmcel paper insulation on there, and then covered that all over with another layer of 50mm Thermafleece batts. This wool-paper mush-wool sandwich was used to contain the Warmcel paper insulation which could blow around and cause a lot of mess when the wind blows a lot outside.

All in all it took two guys about 2 weeks to do this work - they also put celotex in the vertical stud walls of the cupboards - for a total of 4 under-eaves cupboards - and nailed plasterboard over everything to tidy it up and reduce drafts. So including materials and VAT (ARGH! Why is there VAT on domestic insulation materials?) it was pretty expensive.

However, it has made a huge difference to the 1st floor. We’ve had some pretty hard frosts already and the house is nothing like as cold as it was last year. It’s not warm all the time, but it definitely isn’t freezing - now the main source of cold is air leakage into the 1st floor floor space, coming up through the gaps in the floorboards, an altogether different problem…

I had a daft idea a while ago, but who knows one day it may not be so daft.

Basically, all the time our workplaces and public spaces are seeing the production of energy that is "wasted":

1. Overhead lighting is ubiquitous and falls on surfaces that do not do anything useful with it
2. People are walking around (exerting pressure on the floor) and this is doing nothing
3. There is a lot of noise generally, especially in large retail spaces
4. People heat the spaces they are in with their exhalation

For (1) and (2) I wonder if you’d ever be able to make a rugged "smart" floor tile that generates power from light that falls on it (similar to PV but able to be walked on) and from the pressure of peoples’ footsteps on it.

For (3) and (4) perhaps this new method of converting heat and sound into electricity will be possible.

A common thread between them all is the use of piezoelectric devices or similar methods of producing current from pressure.

It’s probably a silly idea and the efficiency would be so low as to be useless, but I don’t know… there’s a lot of heat generated by people, a lot of excess heat in some places (i.e. air conditioning could be obsoleted - a massive win), and across the world there are billions of people walking over man-made surfaces in buildings.

People are already studying the acoustic effects of the force of footsteps on floors I presume for gait-recognition as a kind of security/biometrics thing. Oh, it seems someone else has already had a variation of this idea but with ideas for magnets in shoes as well as some other pressure-related generation - magnets soundscompletely unlikely, you’d need to get both the building and the pedestrians to play ball. Getting just one half on board would be tricky enough.

The other crazy or rather more depressing energy generation of the future I can imagine is effectively the enslavement/exploitation of people in developing nations to generate power for us. It’s not too hard to imagine a company setting up somewhere offering slave-labour pay rates to people to turn cranks or walk treadmills 12 hours per day, to feed the developing countries’ over-inflated energy demands.

I’m sure people would say that something like this would be more equitable than investing in huge amounts of solar PV cells in equatorial countries, as it would boost the economies of the countries by providing income for people who are previously unable to find work. Ugh.

Update: Duh, why haven’t we hooked up all those treadmills in gyms to at least help power the lights and equipment in the gyms? Fat power!

However making it a greener house will be challenging. At the time of arrival there was no insulation other than 5cm or so of rock wool between the first 4 rafters of the loft floor. When it is cold outside (say below 10C) the top floor definitely has that cold and damp feel to it, despite there being no damp - but likely ventilation issues. We also have more than our fair share of drafts.

We have however discovered that we definitely do have cavity walls, despite the odd concrete blocks used to build the place. This is great news and we have people coming to quote for insulating the cavities.

The biggest insulation challenge we have is related to the eaves of the roof. The 1st floor rooms have the eaves coming down through them, to about 1m or so off the floor. This presents us with a very difficult to insulate void, and the depth of the rafters is only 4 inches. I’m seeking spray / infill solutions to at least make some difference.

Of course we have the windows to replace too - they’re the original 1930s Crittal metal-framed windows. The frames themselves are ice cold and the condensation is terrible, even with the poor quality secondary double glazing that is here.

Having had a friend do an energy efficiency survey we know what needs to be done, we’re just trying to find a sensible way to do it all.

A couple of things do really annoy me about the UK. The first is that the government gives grants specifically to landlords to voluntarily improve insulation. i.e. we tax payers are subsidising those who exacerbate the UK housing stock shortage by holding onto multiple properties.
Landlords should be compelled by law to insulate their properties to the highest standard possible or be forced to put the house on the market for sale (or equivalent penalty such as 50% tax on rent received). The subsidy given to them might be acceptable if they were required by law to do the work, but they are not and it is giddying to think of all the hundreds of thousands of rental properties in the UK with poor insulation.

Secondly, plumbers and heat engineeers must be required by law to fit adequate pipe lagging. I am yet to see a house that is not new-build, that has any lagging on sub-floor or loft piping. The heat losses from this must be huge, and I’m sure it accounts for problems where radiators never get up to temperature on the ground floor where the under floor void is very drafty, as in our previous house.

The lagging is so cheap and easy to fit and yet is a nightmare to fit once the floors have all been put back down. There’s no excuse - the plumbers could even earn more to do it if it were required by law!